Protein Kinases, catalytic domain; The protein kinase superfamily is mainly composed of the catalytic domains of serine/threonine-specific and tyrosine-specific protein kinases. It also includes RIO kinases, which are atypical serine protein kinases, aminoglycoside phosphotransferases, and choline kinases. These proteins catalyze the transfer of the gamma-phosphoryl group from ATP to hydroxyl groups in specific substrates such as serine, threonine, or tyrosine residues of proteins.

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 1218251812  22 NDFMFGKLIGEGSFSVVYLAKDVHTSKEWAVKVCEKRQIIRERKQEYVKREREALNRLSgLPGFLNLF 89
Cdd:cd05581     1 NDFKFGKPLGEGSYSTVVLAKEKETGKEYAIKVLDKRHIIKEKKVKYVTIEKEVLSRLA-HPGIVKLY 67

3-Phosphoinositide dependent protein kinase 1 (PDK1) pleckstrin homology (PH) domain; PDK1 plays an important role in insulin and growth factor signalling cascades. It phosphorylates and activates many AGC (cAMP-dependent, cGMP-dependent, protein kinase C (PKC)) family of protein kinases members, including protein kinase B (PKB, also known as Akt), p70 ribosomal S6-kinase (S6K), serum and glucocorticoid responsive kinase (SGK), p90 ribosomal S6 kinase (RSK), and PKC. PDK1 contains an N-terminal serine/threonine kinase domain followed by a PH domain. Following binding of the PH domain to PtdIns(3,4,5)P3 and PtdIns(3,4)P2, PDK1 activates these enzymes by phosphorylating a Ser/Thr residue in their activation loop. PH domains have diverse functions, but in general are involved in targeting proteins to the appropriate cellular location or in the interaction with a binding partner. They share little sequence conservation, but all have a common fold, which is electrostatically polarized. Less than 10% of PH domains bind phosphoinositide phosphates (PIPs) with high affinity and specificity. PH domains are distinguished from other PIP-binding domains by their specific high-affinity binding to PIPs with two vicinal phosphate groups: PtdIns(3,4)P2, PtdIns(4,5)P2 or PtdIns(3,4,5)P3 which results in targeting some PH domain proteins to the plasma membrane. A few display strong specificity in lipid binding. Any specificity is usually determined by loop regions or insertions in the N-terminus of the domain, which are not conserved across all PH domains. PH domains are found in cellular signaling proteins such as serine/threonine kinase, tyrosine kinases, regulators of G-proteins, endocytotic GTPases, adaptors, as well as cytoskeletal associated molecules and in lipid associated enzymes.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1218251812 105 EEQKSDMWHSFAEGELILKKGFVNKRKGaLYVpRKRMLLLTTGPKLIYIDPVQMVKKGEIPWNEKLRAEAKNFKMFFVHT 184
Cdd:cd01262     1 QQQSENWWHFLVNGELILKMGLVDKRKG-LFA-KKRQLILTDGPRLYYVDPVKMVLKGEIPWSPELRPEVKNFKTFFIHT 78

                          90       100       110
                  ....*....|....*....|....*....|
gi 1218251812 185 PHRTYYLEDSQGYALKWCQAIQEMHdKVYK 214
Cdd:cd01262    79 PNRTYYLEDPEGNAKKWCKAIEEVL-KLYK 107

Protein kinase domain;

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|....*..
gi 1218251812  24 FMFGKLIGEGSFSVVYLAKDVHTSKEWAVKVCEKRQiIRERKQEYVKREREALNRLS 80
Cdd:pfam00069   1 YEVLRKLGSGSFGTVYKAKHRDTGKIVAIKKIKKEK-IKKKKDKNILREIKILKKLN 56

Serine/threonine protein kinase [Signal transduction mechanisms];

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|...
gi 1218251812  28 KLIGEGSFSVVYLAKDVHTSKEWAVKVCEKRQIIRERKQEYVKREREALNRLS 80
Cdd:COG0515    13 RLLGRGGMGVVYLARDLRLGRPVALKVLRPELAADPEARERFRREARALARLN 65

3-Phosphoinositide dependent protein kinase 1 (PDK1) pleckstrin homology (PH) domain; PDK1 plays an important role in insulin and growth factor signalling cascades. It phosphorylates and activates many AGC (cAMP-dependent, cGMP-dependent, protein kinase C (PKC)) family of protein kinases members, including protein kinase B (PKB, also known as Akt), p70 ribosomal S6-kinase (S6K), serum and glucocorticoid responsive kinase (SGK), p90 ribosomal S6 kinase (RSK), and PKC. PDK1 contains an N-terminal serine/threonine kinase domain followed by a PH domain. Following binding of the PH domain to PtdIns(3,4,5)P3 and PtdIns(3,4)P2, PDK1 activates these enzymes by phosphorylating a Ser/Thr residue in their activation loop. PH domains have diverse functions, but in general are involved in targeting proteins to the appropriate cellular location or in the interaction with a binding partner. They share little sequence conservation, but all have a common fold, which is electrostatically polarized. Less than 10% of PH domains bind phosphoinositide phosphates (PIPs) with high affinity and specificity. PH domains are distinguished from other PIP-binding domains by their specific high-affinity binding to PIPs with two vicinal phosphate groups: PtdIns(3,4)P2, PtdIns(4,5)P2 or PtdIns(3,4,5)P3 which results in targeting some PH domain proteins to the plasma membrane. A few display strong specificity in lipid binding. Any specificity is usually determined by loop regions or insertions in the N-terminus of the domain, which are not conserved across all PH domains. PH domains are found in cellular signaling proteins such as serine/threonine kinase, tyrosine kinases, regulators of G-proteins, endocytotic GTPases, adaptors, as well as cytoskeletal associated molecules and in lipid associated enzymes.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1218251812 105 EEQKSDMWHSFAEGELILKKGFVNKRKGaLYVpRKRMLLLTTGPKLIYIDPVQMVKKGEIPWNEKLRAEAKNFKMFFVHT 184
Cdd:cd01262     1 QQQSENWWHFLVNGELILKMGLVDKRKG-LFA-KKRQLILTDGPRLYYVDPVKMVLKGEIPWSPELRPEVKNFKTFFIHT 78

                          90       100       110
                  ....*....|....*....|....*....|
gi 1218251812 185 PHRTYYLEDSQGYALKWCQAIQEMHdKVYK 214
Cdd:cd01262    79 PNRTYYLEDPEGNAKKWCKAIEEVL-KLYK 107

Catalytic domain of the Serine/Threonine Kinases, Sucrose nonfermenting 1-related protein kinase subfamily 3; STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. The SnRKs form three different subfamilies designated SnRK1-3. SnRK3 is represented in this cd. The SnRK3 group contains members also known as CBL-interacting protein kinase, salt overly sensitive 2, SOS3-interacting proteins and protein kinase S. These kinases interact with calcium-binding proteins such as SOS3, SCaBPs, and CBL proteins, and are involved in responses to salt stress and in sugar and ABA signaling. The SnRKs belong to a larger superfamily that includes the catalytic domains of other STKs, protein tyrosine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 1218251812  23 DFMFGKLIGEGSFSVVYLAKDVHTSKEWAVKVCEKRQIIRERKQEYVKREREALNRLSGlPGFLNLF 89
Cdd:cd14663     1 RYELGRTLGEGTFAKVKFARNTKTGESVAIKIIDKEQVAREGMVEQIKREIAIMKLLRH-PNIVELH 66

Catalytic subunit of the Serine/Threonine Kinases, cAMP-dependent protein kinases; STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. This subfamily is composed of the cAMP-dependent protein kinases, PKA and PRKX, and similar proteins. The inactive PKA holoenzyme is a heterotetramer composed of two phosphorylated and active catalytic subunits with a dimer of regulatory (R) subunits. Activation is achieved through the binding of the important second messenger cAMP to the R subunits, which leads to the dissociation of PKA into the R dimer and two active subunits. PKA is present ubiquitously in cells and interacts with many different downstream targets. It plays a role in the regulation of diverse processes such as growth, development, memory, metabolism, gene expression, immunity, and lipolysis. PRKX is also reulated by the R subunit and is is present in many tissues including fetal and adult brain, kidney, and lung. It is implicated in granulocyte/macrophage lineage differentiation, renal cell epithelial migration, and tubular morphogenesis in the developing kidney. The PKA-like subfamily is part of a larger superfamily that includes the catalytic domains of other STKs, protein tyrosine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|....*....
gi 1218251812  22 NDFMFGKLIGEGSFSVVYLAKDVHTSKEWAVKVCEKRQIIRERKQEYVKREREALNRLS 80
Cdd:cd05580     1 DDFEFLKTLGTGSFGRVRLVKHKDSGKYYALKILKKAKIIKLKQVEHVLNEKRILSEVR 59

Catalytic domain of the Serine/Threonine protein kinase, Casein Kinase 1; STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. CK1 phosphorylates a variety of substrates including enzymes, transcription and splice factors, cytoskeletal proteins, viral oncogenes, receptors, and membrane-associated proteins. There are mutliple isoforms of CK1 and in mammals, seven isoforms (alpha, beta, gamma1-3, delta, and epsilon) have been characterized. These isoforms differ mainly in the length and structure of their C-terminal non-catalytic region. Some isoforms have several splice variants such as the long (L) and short (S) variants of CK1alpha. CK1 proteins are involved in the regulation of many cellular processes including membrane transport processes, circadian rhythm, cell division, apoptosis, and the development of cancer and neurodegenerative diseases. The CK1 subfamily is part of a larger superfamily that includes the catalytic domains of other protein STKs, protein tyrosine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 1218251812  24 FMFGKLIGEGSFSVVYLAKDVHTSKEWAVKVcEKrqiiRERKQEYVKREREALNRLSGLPGFLNLF 89
Cdd:cd14016     2 YKLVKKIGSGSFGEVYLGIDLKTGEEVAIKI-EK----KDSKHPQLEYEAKVYKLLQGGPGIPRLY 62

Catalytic domain of AMP-activated protein kinase-like Serine/Threonine Kinases; STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. The AMPK-like subfamily is composed of AMPK, MARK, BRSK, NUAK, MELK, SNRK, TSSK, and SIK, among others. LKB1 serves as a master upstream kinase that activates AMPK and most AMPK-like kinases. AMPK, also called SNF1 (sucrose non-fermenting1) in yeasts and SnRK1 (SNF1-related kinase1) in plants, is a heterotrimeric enzyme composed of a catalytic alpha subunit and two regulatory subunits, beta and gamma. It is a stress-activated kinase that serves as master regulator of glucose and lipid metabolism by monitoring carbon and energy supplies, via sensing the cell's AMP:ATP ratio. MARKs phosphorylate tau and related microtubule-associated proteins (MAPs), and regulates microtubule-based intracellular transport. They are involved in embryogenesis, epithelial cell polarization, cell signaling, and neuronal differentiation. BRSKs play important roles in establishing neuronal polarity. TSSK proteins are almost exclusively expressed postmeiotically in the testis and play important roles in spermatogenesis and/or spermiogenesis. The AMPK-like subfamily is part of a larger superfamily that includes the catalytic domains of other STKs, protein tyrosine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|....*..
gi 1218251812  23 DFMFGKLIGEGSFSVVYLAKDVHTSKEWAVKVCEKRQIIrERKQEYVKREREALNRL 79
Cdd:cd14003     1 NYELGKTLGEGSFGKVKLARHKLTGEKVAIKIIDKSKLK-EEIEEKIKREIEIMKLL 56

Catalytic domain of the Serine/Threonine kinase, Aurora kinase; STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. Aurora kinases are key regulators of mitosis and are essential for the accurate and equal division of genomic material from parent to daughter cells. Yeast contains only one Aurora kinase while most higher eukaryotes have two. Vertebrates contain at least 2 Aurora kinases (A and B); mammals contains a third Aurora kinase gene (C). Aurora-A regulates cell cycle events from the late S-phase through the M-phase including centrosome maturation, mitotic entry, centrosome separation, spindle assembly, chromosome alignment, cytokinesis, and mitotic exit. Aurora-A activation depends on its autophosphorylation and binding to the microtubule-associated protein TPX2. Aurora-B is most active at the transition during metaphase to the end of mitosis. It is critical for accurate chromosomal segregation, cytokinesis, protein localization to the centrosome and kinetochore, correct microtubule-kinetochore attachments, and regulation of the mitotic checkpoint. Aurora-C is mainly expressed in meiotically dividing cells; it was originally discovered in mice as a testis-specific STK called Aie1. Both Aurora-B and -C are chromosomal passenger proteins that can form complexes with INCENP and survivin, and they may have redundant cellular functions. The Aurora subfamily is part of a larger superfamily that includes the catalytic domains of other protein STKs, protein tyrosine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|
gi 1218251812  23 DFMFGKLIGEGSFSVVYLAKDVHTSKEWAVKVCEKRQIIRERKQEYVKRE 72
Cdd:cd14007     1 DFEIGKPLGKGKFGNVYLAREKKSGFIVALKVISKSQLQKSGLEHQLRRE 50

Catalytic domain of Protein Kinases; PKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine or tyrosine residues on protein substrates. PKs make up a large family of serine/threonine kinases (STKs), protein tyrosine kinases (PTKs), and dual-specificity PKs that phosphorylate both serine/threonine and tyrosine residues of target proteins. Majority of protein phosphorylation occurs on serine residues while only 1% occurs on tyrosine residues. Protein phosphorylation is a mechanism by which a wide variety of cellular proteins, such as enzymes and membrane channels, are reversibly regulated in response to certain stimuli. PKs often function as components of signal transduction pathways in which one kinase activates a second kinase, which in turn, may act on other kinases; this sequential action transmits a signal from the cell surface to target proteins, which results in cellular responses. The PK family is one of the largest known protein families with more than 100 homologous yeast enzymes and more than 500 human proteins. A fraction of PK family members are pseudokinases that lack crucial residues for catalytic activity. The mutiplicity of kinases allows for specific regulation according to substrate, tissue distribution, and cellular localization. PKs regulate many cellular processes including proliferation, division, differentiation, motility, survival, metabolism, cell-cycle progression, cytoskeletal rearrangement, immunity, and neuronal functions. Many kinases are implicated in the development of various human diseases including different types of cancer. The PK family is part of a larger superfamily that includes the catalytic domains of RIO kinases, aminoglycoside phosphotransferase, choline kinase, phosphoinositide 3-kinase (PI3K), and actin-fragmin kinase.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|.
gi 1218251812  30 IGEGSFSVVYLAKDVHTSKEWAVKVCEKRQIIRERkqEYVKREREALNRLS 80
Cdd:cd00180     1 LGKGSFGKVYKARDKETGKKVAVKVIPKEKLKKLL--EELLREIEILKKLN 49

Catalytic domain of bacterial Serine/Threonine kinases, PknB and similar proteins; STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. This subfamily includes many bacterial eukaryotic-type STKs including Staphylococcus aureus PknB (also called PrkC or Stk1), Bacillus subtilis PrkC, and Mycobacterium tuberculosis Pkn proteins (PknB, PknD, PknE, PknF, PknL, and PknH), among others. S. aureus PknB is the only eukaryotic-type STK present in this species, although many microorganisms encode for several such proteins. It is important for the survival and pathogenesis of S. aureus as it is involved in the regulation of purine and pyrimidine biosynthesis, cell wall metabolism, autolysis, virulence, and antibiotic resistance. M. tuberculosis PknB is essential for growth and it acts on diverse substrates including proteins involved in peptidoglycan synthesis, cell division, transcription, stress responses, and metabolic regulation. B. subtilis PrkC is located at the inner membrane of endospores and functions to trigger spore germination. Bacterial STKs in this subfamily show varied domain architectures. The well-characterized members such as S. aureus and M. tuberculosis PknB, and B. subtilis PrkC, contain an N-terminal cytosolic kinase domain, a transmembrane (TM) segment, and mutliple C-terminal extracellular PASTA domains. The PknB subfamily is part of a larger superfamily that includes the catalytic domains of other protein STKs, protein tyrosine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|...
gi 1218251812  28 KLIGEGSFSVVYLAKDVHTSKEWAVKVCEKRQIIRERKQEYVKREREALNRLS 80
Cdd:cd14014     6 RLLGRGGMGEVYRARDTLLGRPVAIKVLRPELAEDEEFRERFLREARALARLS 58

Serine/threonine protein kinase [Signal transduction mechanisms];

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|...
gi 1218251812  28 KLIGEGSFSVVYLAKDVHTSKEWAVKVCEKRQIIRERKQEYVKREREALNRLS 80
Cdd:COG0515    13 RLLGRGGMGVVYLARDLRLGRPVALKVLRPELAADPEARERFRREARALARLN 65

Catalytic domain of CMGC family Serine/Threonine Kinases; STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. The CMGC family consists of Cyclin-Dependent protein Kinases (CDKs), Mitogen-activated protein kinases (MAPKs) such as Extracellular signal-regulated kinase (ERKs), c-Jun N-terminal kinases (JNKs), and p38, and other kinases. CDKs belong to a large subfamily of STKs that are regulated by their cognate cyclins. Together, they are involved in the control of cell-cycle progression, transcription, and neuronal function. MAPKs serve as important mediators of cellular responses to extracellular signals. They control critical cellular functions including differentiation, proliferation, migration, and apoptosis. They are also implicated in the pathogenesis of many diseases including multiple types of cancer, stroke, diabetes, and chronic inflammation. Other members of the CMGC family include casein kinase 2 (CK2), Dual-specificity tYrosine-phosphorylated and -Regulated Kinase (DYRK), Glycogen Synthase Kinase 3 (GSK3), among many others. The CMGC family is part of a larger superfamily that includes the catalytic domains of other STKs, protein tyrosine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|....*....
gi 1218251812  28 KLIGEGSFSVVYLAKDVHTSKEWAVKvcekrqIIRERK--QEYVKREREALNRLSGLPG 84
Cdd:cd05118     5 RKIGEGAFGTVWLARDKVTGEKVAIK------KIKNDFrhPKAALREIKLLKHLNDVEG 57

Catalytic domain of the Serine/Threonine Kinase, cGMP-dependent protein kinase (cGK or PKG); STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. Mammals have two cGK isoforms from different genes, cGKI and cGKII. cGKI exists as two splice variants, cGKI-alpha and cGKI-beta. cGK consists of an N-terminal regulatory domain containing a dimerization and an autoinhibitory pseudosubstrate region, two cGMP-binding domains, and a C-terminal catalytic domain. Binding of cGMP to both binding sites releases the inhibition of the catalytic center by the pseudosubstrate region, allowing autophosphorylation and activation of the kinase. cGKI is a soluble protein expressed in all smooth muscles, platelets, cerebellum, and kidney. It is also expressed at lower concentrations in other tissues. cGKII is a membrane-bound protein that is most abundantly expressed in the intestine. It is also present in the brain nuclei, adrenal cortex, kidney, lung, and prostate. cGKI is involved in the regulation of smooth muscle tone, smooth cell proliferation, and platelet activation. cGKII plays a role in the regulation of secretion, such as renin secretion by the kidney and aldosterone secretion by the adrenal. It also regulates bone growth and the circadian rhythm. The cGK subfamily is part of a larger superfamily that includes the catalytic domains of other STKs, protein tyrosine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*..
gi 1218251812  30 IGEGSFSVVYLAKDVHTSKEWAVKVCEKRQIIRERKQEYVKREREAL 76
Cdd:cd05572     1 LGVGGFGRVELVQLKSKGRTFALKCVKKRHIVQTRQQEHIFSEKEIL 47

Catalytic domain of the Protein Serine/Threonine Kinase, Serum- and Glucocorticoid-induced Kinase 3; STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. SGK3 (also called cytokine-independent survival kinase or CISK) is expressed in most tissues and is most abundant in the embryo and adult heart and spleen. It was originally discovered in a screen for antiapoptotic genes. It phosphorylates and inhibits the proapoptotic proteins, Bad and FKHRL1. SGK3 also regulates many transporters, ion channels, and receptors. It plays a critical role in hair follicle morphogenesis and hair cycling. The SGK3 subfamily is part of a larger superfamily that includes the catalytic domains of other STKs, protein tyrosine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*....
gi 1218251812  28 KLIGEGSFSVVYLAKDVHTSKEWAVKVCEKRQIIRERKQEYVKREREAL 76
Cdd:cd05604     2 KVIGKGSFGKVLLAKRKRDGKYYAVKVLQKKVILNRKEQKHIMAERNVL 50

Catalytic domain of the Serine/Threonine Kinase, Serum- and Glucocorticoid-induced Kinase 2; STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. SGK2 shows a more restricted distribution than SGK1 and is most abundantly expressed in epithelial tissues including kidney, liver, pancreas, and the choroid plexus of the brain. In vitro cellular assays show that SGK2 can stimulate the activity of ion channels, the glutamate transporter EEAT4, and the glutamate receptors, GluR6 and GLUR1. The SGK2 subfamily is part of a larger superfamily that includes the catalytic domains of other STKs, protein tyrosine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*....
gi 1218251812  28 KLIGEGSFSVVYLAKDVHTSKEWAVKVCEKRQIIRERKQEYVKREREAL 76
Cdd:cd05603     1 KVIGKGSFGKVLLAKRKCDGKFYAVKVLQKKTILKKKEQNHIMAERNVL 49

Catalytic domain of Mitogen-Activated Protein (MAP)/Extracellular signal-Regulated Kinase (ERK) Kinase Kinase 3-like Serine/Threonine Kinases; STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. This subfamily is composed of MEKK3, MEKK2, and related proteins; all contain an N-terminal PB1 domain, which mediates oligomerization, and a C-terminal catalytic domain. MEKK2 and MEKK3 are MAPK kinase kinases (MAPKKKs or MKKK) that activate MEK5 (also called MKK5), which activates ERK5. The ERK5 cascade plays roles in promoting cell proliferation, differentiation, neuronal survival, and neuroprotection. MEKK3 plays an essential role in embryonic angiogenesis and early heart development. MEKK2 and MEKK3 can also activate the MAPKs, c-Jun N-terminal kinase (JNK) and p38, through their respective MAPKKs. The MEKK3-like subfamily is part of a larger superfamily that includes the catalytic domains of other STKs, protein tyrosine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*...
gi 1218251812  27 GKLIGEGSFSVVYLAKDVHTSKEWAVKVCEKRQIIRERKQEYVKRERE 74
Cdd:cd06625     5 GKLLGQGAFGQVYLCYDADTGRELAVKQVEIDPINTEASKEVKALECE 52

protein kinase A catalytic subunit; Provisional

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|....*...
gi 1218251812  23 DFMFGKLIGEGSFSVVYLAKDVHTSKEWAVKVCEKRQIIRERKQEYVKREREALNRLS 80
Cdd:PTZ00263   19 DFEMGETLGTGSFGRVRIAKHKGTGEYYAIKCLKKREILKMKQVQHVAQEKSILMELS 76

Catalytic domain of the Serine/Threonine Kinase, Doublecortin-like kinase (also called Doublecortin-like and CAM kinase-like); STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. DCKL (or DCAMKL) proteins belong to the doublecortin (DCX) family of proteins which are involved in neuronal migration, neurogenesis, and eye receptor development, among others. Family members typically contain tandem doublecortin (DCX) domains at the N-terminus; DCX domains can bind microtubules and serve as protein-interaction platforms. In addition, DCKL proteins contain a C-terminal kinase domain with similarity to CAMKs. They are involved in the regulation of cAMP signaling. Vertebrates contain three DCKL proteins (DCKL1-3); DCKL1 and 2 also contain a serine, threonine, and proline rich domain (SP), while DCKL3 contains only a single DCX domain instead of tandem domains. The DCKL subfamily is part of a larger superfamily that includes the catalytic domains of other STKs, protein tyrosine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|....*..
gi 1218251812  24 FMFGKLIGEGSFSVVYLAKDVHTSKEWAVKVCEKRQIIreRKQEYVKREREALNRLS 80
Cdd:cd14095     2 YDIGRVIGDGNFAVVKECRDKATDKEYALKIIDKAKCK--GKEHMIENEVAILRRVK 56

Catalytic domain of the Serine/Threonine kinases, Liver Kinase B1, Calmodulin Dependent Protein Kinase Kinase, and similar proteins; STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. Both LKB1 and CaMKKs can phosphorylate and activate AMP-activated protein kinase (AMPK). LKB1, also called STK11, serves as a master upstream kinase that activates AMPK and most AMPK-like kinases. LKB1 and AMPK are part of an energy-sensing pathway that links cell energy to metabolism and cell growth. They play critical roles in the establishment and maintenance of cell polarity, cell proliferation, cytoskeletal organization, as well as T-cell metabolism, including T-cell development, homeostasis, and effector function. CaMKKs are upstream kinases of the CaM kinase cascade that phosphorylate and activate CaMKI and CamKIV. They may also phosphorylate other substrates including PKB and AMPK. Vertebrates contain two CaMKKs, CaMKK1 (or alpha) and CaMKK2 (or beta). CaMKK1 is involved in the regulation of glucose uptake in skeletal muscles. CaMKK2 is involved in regulating energy balance, glucose metabolism, adiposity, hematopoiesis, inflammation, and cancer. The LKB1/CaMKK subfamily is part of a larger superfamily that includes the catalytic domains of other STKs, protein tyrosine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|....
gi 1218251812  30 IGEGSFSVVYLAKDVHTSKEWAVKVCEKRQIIRERKQE-----------YVKRE 72
Cdd:cd14008     1 LGRGSFGKVKLALDTETGQLYAIKIFNKSRLRKRREGKndrgkiknaldDVRRE 54

Catalytic domain of the yeast Serine/Threonine Kinases, Rad53 and Cds1; STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. Rad53 and Cds1 are the checkpoint kinase 2 (Chk2) homologs found in budding and fission yeast, respectively. They play a central role in the cell's response to DNA lesions to prevent genome rearrangements and maintain genome integrity. They are phosphorylated in response to DNA damage and incomplete replication, and are essential for checkpoint control. They help promote DNA repair by stalling the cell cycle prior to mitosis in the presence of DNA damage. The Rad53/Cds1 subfamily is part of a larger superfamily that includes the catalytic domains of other protein STKs, protein tyrosine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

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gi 1218251812  23 DFMFGKLIGEGSFSVVYLAKDVHTSKEWAVKVCEKRQIIRERKQ-EYVKREREALNRL 79
Cdd:cd14098     1 KYQIIDRLGSGTFAEVKKAVEVETGKMRAIKQIVKRKVAGNDKNlQLFQREINILKSL 58

Catalytic domain of the Serine/Threonine Kinase, Classical Protein Kinase C beta; STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. The PKC beta isoforms (I and II), generated by alternative splicing of a single gene, are preferentially activated by hyperglycemia-induced DAG (1,2-diacylglycerol) in retinal tissues. This is implicated in diabetic microangiopathy such as ischemia, neovascularization, and abnormal vasodilator function. PKC-beta also plays an important role in VEGF signaling. In addition, glucose regulates proliferation in retinal endothelial cells via PKC-betaI. PKC-beta is also being explored as a therapeutic target in cancer. It contributes to tumor formation and is involved in the tumor host mechanisms of inflammation and angiogenesis. PKCs are classified into three groups (classical, atypical, and novel) depending on their mode of activation and the structural characteristics of their regulatory domain. PKCs undergo three phosphorylations in order to take mature forms. In addition, cPKCs depend on calcium, DAG, and in most cases, phosphatidylserine (PS) for activation. The cPKC-beta subfamily is part of a larger superfamily that includes the catalytic domains of other protein STKs, protein tyrosine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

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gi 1218251812  23 DFMFGKLIGEGSFSVVYLAKDVHTSKEWAVKVCEKRQIIRERKQEYVKREREALnRLSGLPGFL 86
Cdd:cd05616     1 DFNFLMVLGKGSFGKVMLAERKGTDELYAVKILKKDVVIQDDDVECTMVEKRVL-ALSGKPPFL 63

Catalytic domain of Numb-Associated Kinase (NAK)-like Serine/Threonine kinases; STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. This subfamily is composed of Drosophila melanogaster NAK, human BMP-2-inducible protein kinase (BMP2K or BIKe) and similar vertebrate proteins, as well as the Saccharomyces cerevisiae proteins Prk1, Actin-regulating kinase 1 (Ark1), and Akl1. NAK was the first characterized member of this subfamily. It plays a role in asymmetric cell division through its association with Numb. It also regulates the localization of Dlg, a protein essential for septate junction formation. BMP2K contains a nuclear localization signal and a kinase domain that is capable of phosphorylating itself and myelin basic protein. The expression of the BMP2K gene is increase during BMP-2-induced osteoblast differentiation. It may function to control the rate of differentiation. Prk1, Ark1, and Akl1 comprise a subfamily of yeast proteins that are important regulators of the actin cytoskeleton and endocytosis. They share an N-terminal kinase domain but no significant homology in other regions of their sequences. The NAK-like subfamily is part of a larger superfamily that includes the catalytic domains of other protein STKs, protein tyrosine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

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gi 1218251812  28 KLIGEGSFSVVYLAKDVHTSKewavKVCEKRQIIRERKQ-EYVKREREALNRLSG 81
Cdd:cd14037     9 KYLAEGGFAHVYLVKTSNGGN----RAALKRVYVNDEHDlNVCKREIEIMKRLSG 59

Catalytic domain of the Serine/Threonine Kinase, p21-activated kinase; STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. PAKs are Rho family GTPase-regulated kinases that serve as important mediators in the function of Cdc42 (cell division cycle 42) and Rac. PAKs are implicated in the regulation of many cellular processes including growth factor receptor-mediated proliferation, cell polarity, cell motility, cell death and survival, and actin cytoskeleton organization. PAK deregulation is associated with tumor development. PAKs from higher eukaryotes are classified into two groups (I and II), according to their biochemical and structural features. Group I PAKs contain a PBD (p21-binding domain) overlapping with an AID (autoinhibitory domain), a C-terminal catalytic domain, SH3 binding sites and a non-classical SH3 binding site for PIX (PAK-interacting exchange factor). Group II PAKs contain a PBD and a catalytic domain, but lack other motifs found in group I PAKs. Since group II PAKs do not contain an obvious AID, they may be regulated differently from group I PAKs. Group I PAKs interact with the SH3 containing proteins Nck, Grb2 and PIX; no such binding has been demonstrated for group II PAKs. The PAK subfamily is part of a larger superfamily that includes the catalytic domains of other STKs, protein tyrosine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

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gi 1218251812  24 FMFGKLIGEGSFSVVYLAKDVHTSKEWAVKVCekrqIIRERKQEYVKRE 72
Cdd:cd06614     2 YKNLEKIGEGASGEVYKATDRATGKEVAIKKM----RLRKQNKELIINE 46

Catalytic domain of testis-specific serine/threonine kinases and similar proteins; STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. TSSK proteins are almost exclusively expressed postmeiotically in the testis and play important roles in spermatogenesis and/or spermiogenesis. There are five mammalian TSSK proteins which show differences in their localization and timing of expression. TSSK1 and TSSK2 are expressed specifically in meiotic and postmeiotic spermatogenic cells, respectively. TSSK3 has been reported to be expressed in the interstitial Leydig cells of adult testis. TSSK4, also called TSSK5, is expressed in testis from haploid round spermatids to mature spermatozoa. TSSK6, also called SSTK, is expressed at the head of elongated sperm. TSSK1/TSSK2 double knock-out and TSSK6 null mice are sterile without manifesting other defects, making these kinases viable targets for male contraception. The TSSK-like subfamily is part of a larger superfamily that includes the catalytic domains of other STKs, protein tyrosine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

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gi 1218251812  24 FMFGKLIGEGSFSVVYLAKDVHTSKE--WAVKVCEKRQIIRERKQEYVKREREALNRLS 80
Cdd:cd14080     2 YRLGKTIGEGSYSKVKLAEYTKSGLKekVACKIIDKKKAPKDFLEKFLPRELEILRKLR 60

Catalytic domain of STE family Protein Kinases; PKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine (ST) or tyrosine residues on protein substrates. This family is composed of STKs, and some dual-specificity PKs that phosphorylate both threonine and tyrosine residues of target proteins. Most members are kinases involved in mitogen-activated protein kinase (MAPK) signaling cascades, acting as MAPK kinases (MAPKKs), MAPKK kinases (MAPKKKs), or MAPKKK kinases (MAP4Ks). The MAPK signaling pathways are important mediators of cellular responses to extracellular signals. The pathways involve a triple kinase core cascade comprising of the MAPK, which is phosphorylated and activated by a MAPKK, which itself is phosphorylated and activated by a MAPKKK. Each MAPK cascade is activated either by a small GTP-binding protein or by an adaptor protein, which transmits the signal either directly to a MAPKKK to start the triple kinase core cascade or indirectly through a mediator kinase, a MAP4K. Other STE family members include p21-activated kinases (PAKs) and class III myosins, among others. PAKs are Rho family GTPase-regulated kinases that serve as important mediators in the function of Cdc42 (cell division cycle 42) and Rac. Class III myosins are motor proteins containing an N-terminal kinase catalytic domain and a C-terminal actin-binding domain, which can phosphorylate several cytoskeletal proteins, conventional myosin regulatory light chains, as well as autophosphorylate the C-terminal motor domain. They play an important role in maintaining the structural integrity of photoreceptor cell microvilli. The STE family is part of a larger superfamily that includes the catalytic domains of other STKs, protein tyrosine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

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gi 1218251812  23 DFMFGKLIGEGSFSVVYLAKDVHTSKEWAVKV------CEKRQIIRE 63
Cdd:cd05122     1 LFEILEKIGKGGFGVVYKARHKKTGQIVAIKKinleskEKKESILNE 47

The catalytic domain of the Serine/Threonine Kinase, Glycogen Synthase Kinase 3; STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. GSK3 is a mutifunctional kinase involved in many cellular processes including cell division, proliferation, differentiation, adhesion, and apoptosis. In plants, GSK3 plays a role in the response to osmotic stress. In Caenorhabditis elegans, it plays a role in regulating normal oocyte-to-embryo transition and response to oxidative stress. In Chlamydomonas reinhardtii, GSK3 regulates flagellar length and assembly. In mammals, there are two isoforms, GSK3alpha and GSK3beta, which show both distinct and redundant functions. The two isoforms differ mainly in their N-termini. They are both involved in axon formation and in Wnt signaling.They play distinct roles in cardiogenesis, with GSKalpha being essential in cardiomyocyte survival, and GSKbeta regulating heart positioning and left-right symmetry. GSK3beta was first identified as a regulator of glycogen synthesis, but has since been determined to play other roles. It regulates the degradation of beta-catenin and IkB. Beta-catenin is the main effector of Wnt, which is involved in normal haematopoiesis and stem cell function. IkB is a central inhibitor of NF-kB, which is critical in maintaining leukemic cell growth. GSK3beta is enriched in the brain and is involved in regulating neuronal signaling pathways. It is implicated in the pathogenesis of many diseases including Type II diabetes, obesity, mood disorders, Alzheimer's disease, osteoporosis, and some types of cancer, among others. The GSK3 subfamily is part of a larger superfamily that includes the catalytic domains of other STKs, protein tyrosine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

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gi 1218251812  28 KLIGEGSFSVVYLAKDVHTSKEWAVK-VC-EKR------QIIRERK 65
Cdd:cd14137    10 KVIGSGSFGVVYQAKLLETGEVVAIKkVLqDKRyknrelQIMRRLK 55

Catalytic domain of the Serine/Threonine Kinase, Cyclin-Dependent protein Kinase 7; STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. CDK7 plays essential roles in the cell cycle and in transcription. It associates with cyclin H and MAT1 and acts as a CDK-Activating Kinase (CAK) by phosphorylating and activating cell cycle CDKs (CDK1/2/4/6). In the brain, it activates CDK5. CDK7 is also a component of the general transcription factor TFIIH, which phosphorylates the C-terminal domain (CTD) of RNA polymerase II when it is bound with unphosphorylated DNA, as present in the pre-initiation complex. Following phosphorylation, the CTD dissociates from the DNA which allows transcription initiation. CDKs belong to a large family of STKs that are regulated by their cognate cyclins. Together, they are involved in the control of cell-cycle progression, transcription, and neuronal function. The CDK7 subfamily is part of a larger superfamily that includes the catalytic domains of other STKs, protein tyrosine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

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gi 1218251812  24 FMFGKLIGEGSFSVVYLAKDVHTSKEWAVK 53
Cdd:cd07841     2 YEKGKKLGEGTYAVVYKARDKETGRIVAIK 31

Catalytic domain of the Serine/Threonine kinase, Calcium/calmodulin-dependent protein kinase Type I gamma; STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. CaMKs are multifunctional calcium and calmodulin (CaM) stimulated STKs involved in cell cycle regulation. The CaMK family includes CaMKI, CaMKII, CaMKIV, and CaMK kinase (CaMKK). In vertebrates, there are four CaMKI proteins encoded by different genes (alpha, beta, gamma, and delta), each producing at least one variant. CaMKs contain an N-terminal catalytic domain and a C-terminal regulatory domain that harbors a CaM binding site. CaMKI proteins are monomeric and they play pivotal roles in the nervous system, including long-term potentiation, dendritic arborization, neurite outgrowth, and the formation of spines, synapses, and axons. In addition, they may be involved in osteoclast differentiation and bone resorption. The CaMKI-gamma subfamily is part of a larger superfamily that includes the catalytic domains of other protein kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

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gi 1218251812  24 FMFGKLIGEGSFSVVYLAKDVHTSKEWAVKVCEKRQIIRERKQE 67
Cdd:cd14166     5 FIFMEVLGSGAFSEVYLVKQRSTGKLYALKCIKKSPLSRDSSLE 48

Catalytic domain of the Serine/Threonine kinase, Calcium/calmodulin-dependent protein kinase Type I; STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. CaMKs are multifunctional calcium and calmodulin (CaM) stimulated STKs involved in cell cycle regulation. There are several types of CaMKs including CaMKI, CaMKII, and CaMKIV. In vertebrates, there are four CaMKI proteins encoded by different genes (alpha, beta, gamma, and delta), each producing at least one variant. CaMKs contain an N-terminal catalytic domain and a C-terminal regulatory domain that harbors a CaM binding site. CaMKI proteins are monomeric and they play pivotal roles in the nervous system, including long-term potentiation, dendritic arborization, neurite outgrowth, and the formation of spines, synapses, and axons. In addition, they may be involved in osteoclast differentiation and bone resorption. The CaMKI subfamily is part of a larger superfamily that includes the catalytic domains of other protein kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

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gi 1218251812  24 FMFGKLIGEGSFSVVYLAKDVHTSKEWAVKVCEKRQIirERKQEYVKREREALNRLS 80
Cdd:cd14083     5 YEFKEVLGTGAFSEVVLAEDKATGKLVAIKCIDKKAL--KGKEDSLENEIAVLRKIK 59

Catalytic domain of the Serine/Threonine Kinase, Protein Kinase B gamma (also called Akt3); STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. PKB-gamma is predominantly expressed in neuronal tissues. Mice deficient in PKB-gamma show a reduction in brain weight due to the decreases in cell size and cell number. PKB-gamma has also been shown to be upregulated in estrogen-deficient breast cancer cells, androgen-independent prostate cancer cells, and primary ovarian tumors. It acts as a key mediator in the genesis of ovarian cancer. PKB contains an N-terminal pleckstrin homology (PH) domain and a C-terminal catalytic domain. The PKB-gamma subfamily is part of a larger superfamily that includes the catalytic domains of other STKs, protein tyrosine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

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gi 1218251812  18 RRSANDFMFGKLIGEGSFSVVYLAKDVHTSKEWAVKVCEKRQIIRERKQEYVKREREAL 76
Cdd:cd05593    11 RKTMNDFDYLKLLGKGTFGKVILVREKASGKYYAMKILKKEVIIAKDEVAHTLTESRVL 69

Catalytic domain of Fungal Pat1-like Serine/Threonine kinases; STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. This subfamily is composed of Schizosaccharomyces pombe Pat1 (also called Ran1), Saccharomyces cerevisiae VHS1 and KSP1, and similar fungal STKs. Pat1 blocks Mei2, an RNA-binding protein which is indispensable in the initiation of meiosis. Pat1 is inactivated and Mei2 activated, which initiates meiosis, under nutrient-deprived conditions through a signaling cascade involving Ste11. Meiosis induced by Pat1 inactivation may show different characteristics than normal meiosis including aberrant positioning of centromeres. VHS1 was identified in a screen for suppressors of cell cycle arrest at the G1/S transition, while KSP1 may be involved in regulating PRP20, which is required for mRNA export and maintenance of nuclear structure. The Pat1-like subfamily is part of a larger superfamily that includes the catalytic domains of other protein STKs, protein tyrosine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

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gi 1218251812  30 IGEGSFSVVYLAKDVHTSKEWAVKVCEK----RQIIRERKQEYVKREREALNRLSGLPGFLNL 88
Cdd:cd13993     8 IGEGAYGVVYLAVDLRTGRKYAIKCLYKsgpnSKDGNDFQKLPQLREIDLHRRVSRHPNIITL 70

Catalytic domain of the Serine/Threonine protein kinase, cyclin G-Associated Kinase; STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. GAK, also called auxilin-2, contains an N-terminal kinase domain that phosphorylates the mu subunits of adaptor protein (AP) 1 and AP2. In addition, it contains an auxilin-1-like domain structure consisting of PTEN-like, clathrin-binding, and J domains. Like auxilin-1, GAK facilitates Hsc70-mediated dissociation of clathrin from clathrin-coated vesicles. GAK is expressed ubiquitously and is enriched in the Golgi, unlike auxilin-1 which is nerve-specific. GAK also plays regulatory roles outside of clathrin-mediated membrane traffic including the maintenance of centrosome integrity and chromosome congression, neural patterning, survival of neurons, and immune responses through interaction with the interleukin 12 receptor. It also interacts with the androgen receptor, acting as a transcriptional coactivator, and its expression is significantly increased with the progression of prostate cancer. The GAK subfamily is part of a larger superfamily that includes the catalytic domains of other protein STKs, protein tyrosine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

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gi 1218251812  28 KLIGEGSFSVVYLAKDVHTSKEWAVkvceKRQII-RERKQEYVKREREALNRLSGLPGFLN 87
Cdd:cd14036     6 RVIAEGGFAFVYEAQDVGTGKEYAL----KRLLSnEEEKNKAIIQEINFMKKLSGHPNIVQ 62

Catalytic domain of the Serine/Threonine Kinases, MAP/microtubule affinity-regulating kinases; STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. MARKs, also called Partitioning-defective 1 (Par1) proteins, function as regulators of diverse cellular processes in nematodes, Drosophila, yeast, and vertebrates. They are involved in embryogenesis, epithelial cell polarization, cell signaling, and neuronal differentiation. MARKs phosphorylate tau and related microtubule-associated proteins (MAPs), and regulates microtubule-based intracellular transport. Vertebrates contain four isoforms, namely MARK1 (or Par1c), MARK2 (or Par1b), MARK3 (Par1a), and MARK4 (or MARKL1). Known substrates of MARKs include the cell cycle-regulating phosphatase Cdc25, tyrosine phosphatase PTPH1, MAPK scaffolding protein KSR1, class IIa histone deacetylases, and plakophilin 2. The MARK subfamily is part of a larger superfamily that includes the catalytic domains of other STKs, protein tyrosine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

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gi 1218251812  24 FMFGKLIGEGSFSVVYLAKDVHTSKEWAVKVCEKRQI 60
Cdd:cd14072     2 YRLLKTIGKGNFAKVKLARHVLTGREVAIKIIDKTQL 38

Catalytic domain of the Serine/Threonine Kinase, MAPK/MAK/MRK Overlapping Kinase; STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. MOK, also called Renal tumor antigen 1 (RAGE-1), is widely expressed and is enriched in testis, kidney, lung, and brain. It is expressed in approximately 50% of renal cell carcinomas (RCC) and is a potential target for immunotherapy. MOK is stabilized by its association with the HSP90 molecular chaperone. It is induced by the transcription factor Cdx2 and may be involved in regulating intestinal epithelial development and differentiation. The MOK subfamily is part of a larger superfamily that includes the catalytic domains of other STKs, protein tyrosine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

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gi 1218251812  30 IGEGSFSVVYLAKDVHTSKEWAVKvCEKrQIIRERKQEYVKREREALNRLSGLPGFLNL 88
Cdd:cd07831     7 IGEGTFSEVLKAQSRKTGKYYAIK-CMK-KHFKSLEQVNNLREIQALRRLSPHPNILRL 63

Catalytic domain of Mammalian Ste20-like protein kinase 3-like Serine/Threonine Kinases; STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. This subfamily is composed of MST3, MST4, STK25, Schizosaccharomyces pombe Nak1 and Sid1, Saccharomyces cerevisiae sporulation-specific protein 1 (SPS1), and related proteins. Nak1 is required by fission yeast for polarizing the tips of actin cytoskeleton and is involved in cell growth, cell separation, cell morphology and cell-cycle progression. Sid1 is a component in the septation initiation network (SIN) signaling pathway, and plays a role in cytokinesis. SPS1 plays a role in regulating proteins required for spore wall formation. MST4 plays a role in mitogen-activated protein kinase (MAPK) signaling during cytoskeletal rearrangement, morphogenesis, and apoptosis. MST3 phosphorylates the STK NDR and may play a role in cell cycle progression and cell morphology. STK25 may play a role in the regulation of cell migration and polarization. The MST3-like subfamily is part of a larger superfamily that includes the catalytic domains of other STKs, protein tyrosine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

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gi 1218251812  28 KLIGEGSFSVVYLAKDVHTSKEWAVKV 54
Cdd:cd06609     7 ERIGKGSFGEVYKGIDKRTNQVVAIKV 33

Catalytic domain of Serine/Threonine Kinase 16; STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. STK16 is associated with many names including Myristylated and Palmitylated Serine/threonine Kinase 1 (MPSK1), Kinase related to cerevisiae and thaliana (Krct), and Protein Kinase expressed in day 12 fetal liver (PKL12). It is widely expressed in mammals with highest levels found in liver, testis, and kidney. It is localized in the Golgi but is translocated to the nucleus upon disorganization of the Golgi. STK16 is constitutively active and is capable of phosphorylating itself and other substrates. It may be involved in regulating stromal-epithelial interactions during mammary gland ductal morphogenesis. It may also function as a transcriptional co-activator of type-C natriuretic peptide and VEGF. The STK16 subfamily is part of a larger superfamily that includes the catalytic domains of other protein STKs, protein tyrosine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

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gi 1218251812  24 FMFGKLIGEGSFSVVYLAKDVHTSKEWAVK 53
Cdd:cd13986     2 YRIQRLLGEGGFSFVYLVEDLSTGRLYALK 31