dimerization/docking (D/D) domains found in the cAMP-dependent protein kinase regulatory subunit (PRKAR) and the DPY30/SDC1-like family; This hierarchy includes the dimerization/docking (D/D) domains of type I and type II cAMP-dependent protein kinase (PKA) regulatory (R) subunits, DPY30 from animals and its homologs, SDC1 from yeasts, and similar domains. PKA is a serine/threonine kinase (STK), catalyzing the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. The inactive PKA holoenzyme is a heterotetramer composed of two phosphorylated and active catalytic subunits with a dimer of 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. There are two classes of R subunits, RI and RII; each exists as two isoforms (alpha and beta) from distinct genes. These functionally non-redundant R isoforms allow for specificity in PKA signaling. The R subunit contains an N-terminal D/D domain, a linker with an inhibitory sequence (IS), and two c-AMP binding domains. The D/D domain dimerizes to form a four-helix bundle that serves as a docking site for A-kinase-anchoring proteins (AKAPs), which facilitates the localization of PKA to specific sites in the cell. DPY30, also called dumpy-30, was initially discovered in Caenorhabditis elegans as a key player in X chromosome dosage compensation. Human DPY30 plays a dual function in moderately regulating the methyltransferase activity of SET1/COMPASS (COMplex of Proteins ASsociated with Set1) enzymes and contributing to the recruitment of the complex to chromatin. Yeast SDC1 (suppressor of CDC25 protein 1) is the smallest subunit of COMPASS (COMplex of Proteins ASsociated with Set1) and interacts exclusively with Bre2 at the distal end of the catalytic module. It positively regulates the COMPASS catalytic module by stabilizing the non-canonical Bre2 SPRY domain. DPY30/SDC1 contains a C-terminal helical bundle domain that directly interacts with Ash2L (in human)/Bre2 (in yeast) COMPASS through the DPY30-binding motif (DBM). The DPY30/SDC1 helical bundle domain, also called D/D domain, is formed of two alpha-helices that may be analogous to the D/D domain found in regulatory subunit of PKA.

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gi 386771227  71 RIFLEQEVVPILMEGMLGLAREMPRDPIGYLQKFWLddKHK 111
Cdd:cd22965    2 RQYLDKTVVPVLLEGLKELAKERPEDPLEFLAEYLL--KNS 40

dimerization/docking (D/D) domain found in the DPY30/SDC1 family; This family includes DPY30 from animals and its homologs, including SDC1 from yeast. DPY30, also called dumpy-30, was initially discovered in Caenorhabditis elegans as a key player in X chromosome dosage compensation. Human DPY30 plays a dual function in moderately allosterically regulating the methyltransferase activity of SET1/COMPASS (COMplex of Proteins ASsociated with Set1) enzymes and contributing to the recruitment of the complex to chromatin. DPY30 is the core component of several methyltransferase-containing complexes including MLL1/MLL, MLL2/3 (also named ASCOM complex) and MLL4/WBP7. As part of the MLL1/MLL complex, DPY30 is involved in the methylation of histone H3 at 'Lys-4', particularly trimethylation. Histone H3 'Lys-4' methylation represents a specific tag for epigenetic transcriptional activation. In a teratocarcinoma cell, DPY30 plays a crucial role in retinoic acid-induced differentiation along the neural lineage, regulating gene induction and H3 'Lys-4' methylation at key developmental loci. It may also play an indirect or direct role in endosomal transport. Yeast SDC1, also called complex proteins associated with SET1 (COMPASS) protein SDC1, Set1C component SDC1, or suppressor of CDC25 protein 1, is the smallest subunit of COMPASS and interacts exclusively with Bre2 at the distal end of the catalytic module. It positively regulates the COMPASS catalytic module by stabilizing the non-canonical Bre2 SPRY domain. The COMPASS (Set1C) complex specifically mono-, di- and trimethylates histone H3 to form H3K4me1/2/3, which subsequently activates gene expression by regulating transcription elongation and plays a role in telomere length maintenance. This model corresponds to the C-terminal helical bundle domain of DPY30/SDC1, which is called dimerization/docking (D/D) domain. It forms a homodimer, which directly interacts with the Ash2L (Bre2 in yeast) subunit of COMPASS through its DPY30-binding motif (DBM).

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gi 386771227  71 RIFLEQEVVPILMEGMLGLAREMPRDPIGYLQKFWLddKHK 111
Cdd:cd22965    2 RQYLDKTVVPVLLEGLKELAKERPEDPLEFLAEYLL--KNS 40

dimerization/docking (D/D) domain found in the DPY30/SDC1 family; This family includes DPY30 from animals and its homologs, including SDC1 from yeast. DPY30, also called dumpy-30, was initially discovered in Caenorhabditis elegans as a key player in X chromosome dosage compensation. Human DPY30 plays a dual function in moderately allosterically regulating the methyltransferase activity of SET1/COMPASS (COMplex of Proteins ASsociated with Set1) enzymes and contributing to the recruitment of the complex to chromatin. DPY30 is the core component of several methyltransferase-containing complexes including MLL1/MLL, MLL2/3 (also named ASCOM complex) and MLL4/WBP7. As part of the MLL1/MLL complex, DPY30 is involved in the methylation of histone H3 at 'Lys-4', particularly trimethylation. Histone H3 'Lys-4' methylation represents a specific tag for epigenetic transcriptional activation. In a teratocarcinoma cell, DPY30 plays a crucial role in retinoic acid-induced differentiation along the neural lineage, regulating gene induction and H3 'Lys-4' methylation at key developmental loci. It may also play an indirect or direct role in endosomal transport. Yeast SDC1, also called complex proteins associated with SET1 (COMPASS) protein SDC1, Set1C component SDC1, or suppressor of CDC25 protein 1, is the smallest subunit of COMPASS and interacts exclusively with Bre2 at the distal end of the catalytic module. It positively regulates the COMPASS catalytic module by stabilizing the non-canonical Bre2 SPRY domain. The COMPASS (Set1C) complex specifically mono-, di- and trimethylates histone H3 to form H3K4me1/2/3, which subsequently activates gene expression by regulating transcription elongation and plays a role in telomere length maintenance. This model corresponds to the C-terminal helical bundle domain of DPY30/SDC1, which is called dimerization/docking (D/D) domain. It forms a homodimer, which directly interacts with the Ash2L (Bre2 in yeast) subunit of COMPASS through its DPY30-binding motif (DBM).

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                 ....*....|....*....|....*....|....*....|.
gi 386771227  71 RIFLEQEVVPILMEGMLGLAREMPRDPIGYLQKFWLddKHK 111
Cdd:cd22965    2 RQYLDKTVVPVLLEGLKELAKERPEDPLEFLAEYLL--KNS 40

dimerization/docking (D/D) domain found in adenylate kinase 7 and similar proteins; Adenylate kinase (AK7, EC2.7.4.3/EC 2.7.4.6), also called ATP-AMP transphosphorylase 7, is a nucleoside monophosphate (NMP) kinase that catalyzes the reversible transfer of the terminal phosphate group between nucleoside triphosphates and monophosphates. It has highest activity toward AMP, and weaker activity toward dAMP, CMP and dCMP. It also displays broad nucleoside diphosphate kinase activity. AK7 is involved in maintaining ciliary structure and function. This model corresponds to the C-terminal domain of AK7, which shows high sequence similarity to the dimerization/docking (D/D) domain of protein DPY-30/SDC1.

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gi 386771227  71 RIFLEQEVVPILMEGMLGLAREMPRDPIGYLQKF 104
Cdd:cd22967    3 RNYLMKYVMPTLTEGLVEVCKVRPEDPVDFLAEY 36

dimerization/docking (D/D) domain found in the DPY30/SDC1-like family; The DPY30/SDC1-like family includes DPY30 from animals and its homolog SDC1 from yeast, DPY30 domain-containing protein (DYDC), adenylate kinase 7 (AK7), IQ domain-containing protein K (IQCK), nucleoside diphosphate kinase homolog 5 (NDKH5), EF-hand calcium-binding domain-containing protein 5 (EFCAB5), and Chlamydomonas reinhardtii flagellar radial spoke proteins, RSP2 and RSP23. DPY30, also called dumpy-30, was initially discovered in Caenorhabditis elegans as a key player in X chromosome dosage compensation. Human DPY30 plays a dual function in moderately allosterically regulating the methyltransferase activity of SET1/COMPASS (COMplex of Proteins ASsociated with Set1) enzymes and contributing to the recruitment of the complex to chromatin. Yeast SDC1, also called complex proteins associated with SET1 protein SDC1, Set1C component SDC1, or suppressor of CDC25 protein 1, is the smallest subunit of COMPASS (COMplex of Proteins ASsociated with Set1) and interacts exclusively with Bre2 at the distal end of the catalytic module. It positively regulates the COMPASS catalytic module by stabilizing the non-canonical Bre2 SPRY domain. DYDC1 plays a crucial role during acrosome biogenesis. AK7 (EC2.7.4.3/EC 2.7.4.6), also called ATP-AMP transphosphorylase 7, is a nucleoside monophosphate (NMP) kinase that catalyzes the reversible transfer of the terminal phosphate group between nucleoside triphosphates and monophosphates. It is involved in maintaining ciliary structure and function. IQ motif-containing proteins may play an active role in cell polarization and migration, and even in ciliary function. The function of IQCK remains unclear. NDKH5, also called NME5, NDP kinase homolog 5, inhibitor of p53-induced apoptosis-beta (IPIA-beta), testis-specific nm23 homolog, or nm23-H5, is specifically expressed in testis germinal cells. It may not have NDK kinase activity. It confers protection from cell death by Bax and alters the cellular levels of several antioxidant enzymes including Gpx5. It may play a role in spermiogenesis by increasing the ability of late-stage spermatids to eliminate reactive oxygen species. RSP2 is a calmodulin binding spoke stalk protein required for motility in Chlamydomonas reinhardtii. It binds calmodulin in a calcium-dependent manner. RSP23, also called p61, is a functional Ca2+/calmodulin-regulated nucleoside diphosphate kinase (NDK) from the flagella of Chlamydomonas that is present in the radial spoke stalk. It binds calmodulin in a calcium-dependent manner. Members of this family contain a DPY30/SDC1 helical bundle domain that is formed by two alpha-helices. The DPY30/SDC1 helical bundle domain is also called D/D domain and might be analogous to the D/D domain found in the regulatory subunit of cAMP-dependent protein kinase (PKA).

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gi 386771227  74 LEQEVVPILMEGMLGLAREMPRDPIGYLQKF 104
Cdd:cd22958    5 LSETVLPTLIPALAELLKARPEDPLEWLAEY 35