Basic leucine zipper (bZIP) domain of Cyclic AMP-responsive element-binding protein 3 (CREB3) and similar proteins: a DNA-binding and dimerization domain; This subfamily is composed of CREB3 (also called LZIP or Luman), and the CREB3-like proteins CREB3L1 (or OASIS), CREB3L2, CREB3L3 (or CREBH), and CREB3L4 (or AIbZIP). They are type II membrane-associated members of the Basic leucine zipper (bZIP) family of transcription factors, with their N-termini facing the cytoplasm and their C-termini penetrating through the ER membrane. They contain an N-terminal transcriptional activation domain followed bZIP and transmembrane domains, and a C-terminal tail. They play important roles in ER stress and the unfolded protein response (UPR), as well as in many other biological processes such as cell secretion, bone and cartilage formation, and carcinogenesis. bZIP factors act in networks of homo and heterodimers in the regulation of a diverse set of cellular processes. The bZIP structural motif contains a basic region and a leucine zipper, composed of alpha helices with leucine residues 7 amino acids apart, which stabilize dimerization with a parallel leucine zipper domain. Dimerization of leucine zippers creates a pair of the adjacent basic regions that bind DNA and undergo conformational change. Dimerization occurs in a specific and predictable manner resulting in hundreds of dimers having unique effects on transcription.

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|.
gi 808355254 283 LKIVRRKIKNKLSAQESRRKRKEYIDALEGRLHCFSEENKSLKKQVHQLEASNRDLQQKLH 343
Cdd:cd14689    1 LKKVRRKIRNKISAQESRRRKKEYIDGLESRVAACTAENQELKKKVEELEKQNRSLLSQLR 61

Basic leucine zipper (bZIP) domain of Cyclic AMP-responsive element-binding protein 3 (CREB3) and similar proteins: a DNA-binding and dimerization domain; This subfamily is composed of CREB3 (also called LZIP or Luman), and the CREB3-like proteins CREB3L1 (or OASIS), CREB3L2, CREB3L3 (or CREBH), and CREB3L4 (or AIbZIP). They are type II membrane-associated members of the Basic leucine zipper (bZIP) family of transcription factors, with their N-termini facing the cytoplasm and their C-termini penetrating through the ER membrane. They contain an N-terminal transcriptional activation domain followed bZIP and transmembrane domains, and a C-terminal tail. They play important roles in ER stress and the unfolded protein response (UPR), as well as in many other biological processes such as cell secretion, bone and cartilage formation, and carcinogenesis. bZIP factors act in networks of homo and heterodimers in the regulation of a diverse set of cellular processes. The bZIP structural motif contains a basic region and a leucine zipper, composed of alpha helices with leucine residues 7 amino acids apart, which stabilize dimerization with a parallel leucine zipper domain. Dimerization of leucine zippers creates a pair of the adjacent basic regions that bind DNA and undergo conformational change. Dimerization occurs in a specific and predictable manner resulting in hundreds of dimers having unique effects on transcription.

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|.
gi 808355254 283 LKIVRRKIKNKLSAQESRRKRKEYIDALEGRLHCFSEENKSLKKQVHQLEASNRDLQQKLH 343
Cdd:cd14689    1 LKKVRRKIRNKISAQESRRRKKEYIDGLESRVAACTAENQELKKKVEELEKQNRSLLSQLR 61

bZIP transcription factor; The Pfam entry includes the basic region and the leucine zipper region.

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                  ....*....|....*....|....*....|....*....|....*....|....*....|
gi 808355254  284 KIVRRKIKNKLSAQESRRKRKEYIDALEGRLHCFSEENKSLKKQVHQLEASNRDLQQKLH 343
Cdd:pfam00170   1 KREKRKQSNREAARRSRQRKQAYIEELERRVKALEGENKTLRSELEELKKEVEKLKSKNK 60

Basic leucine zipper (bZIP) domain of Cyclic AMP-responsive element-binding protein 3 (CREB3) and similar proteins: a DNA-binding and dimerization domain; This subfamily is composed of CREB3 (also called LZIP or Luman), and the CREB3-like proteins CREB3L1 (or OASIS), CREB3L2, CREB3L3 (or CREBH), and CREB3L4 (or AIbZIP). They are type II membrane-associated members of the Basic leucine zipper (bZIP) family of transcription factors, with their N-termini facing the cytoplasm and their C-termini penetrating through the ER membrane. They contain an N-terminal transcriptional activation domain followed bZIP and transmembrane domains, and a C-terminal tail. They play important roles in ER stress and the unfolded protein response (UPR), as well as in many other biological processes such as cell secretion, bone and cartilage formation, and carcinogenesis. bZIP factors act in networks of homo and heterodimers in the regulation of a diverse set of cellular processes. The bZIP structural motif contains a basic region and a leucine zipper, composed of alpha helices with leucine residues 7 amino acids apart, which stabilize dimerization with a parallel leucine zipper domain. Dimerization of leucine zippers creates a pair of the adjacent basic regions that bind DNA and undergo conformational change. Dimerization occurs in a specific and predictable manner resulting in hundreds of dimers having unique effects on transcription.

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|.
gi 808355254 283 LKIVRRKIKNKLSAQESRRKRKEYIDALEGRLHCFSEENKSLKKQVHQLEASNRDLQQKLH 343
Cdd:cd14689    1 LKKVRRKIRNKISAQESRRRKKEYIDGLESRVAACTAENQELKKKVEELEKQNRSLLSQLR 61

Basic leucine zipper (bZIP) domain of X-box binding protein 1 (XBP1) and similar proteins: a DNA-binding and dimerization domain; XBP1, a member of the Basic leucine zipper (bZIP) family, is the key transcription factor that orchestrates the unfolded protein response (UPR). It is the most conserved component of the UPR and is critical for cell fate determination in response to ER stress. The inositol-requiring enzyme 1 (IRE1)-XBP1 pathway is one of the three major sensors at the ER membrane that initiates the UPR upon activation. IRE1, a type I transmembrane protein kinase and endoribonuclease, oligomerizes upon ER stress leading to its increased activity. It splices the XBP1 mRNA, producing a variant that translocates to the nucleus and activates its target genes, which are involved in protein folding, degradation, and trafficking. bZIP factors act in networks of homo and heterodimers in the regulation of a diverse set of cellular processes. The bZIP structural motif contains a basic region and a leucine zipper, composed of alpha helices with leucine residues 7 amino acids apart, which stabilize dimerization with a parallel leucine zipper domain. Dimerization of leucine zippers creates a pair of the adjacent basic regions that bind DNA and undergo conformational change. Dimerization occurs in a specific and predictable manner resulting in hundreds of dimers having unique effects on transcription.

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                 ....*....|....*....|....*....|....*....|....*....|....*..
gi 808355254 282 SLKIVRRKIKNKLSAQESRRKRKEYIDALEGRLHCFSEENKSLKKQVHQLEASNRDL 338
Cdd:cd14691    1 EEKDLRRKLKNRVAAQTARDRKKARMDELEERVRELEEENQKLRAENESLRARNEDL 57

Basic leucine zipper (bZIP) domain of bZIP transcription factors: a DNA-binding and dimerization domain; Basic leucine zipper (bZIP) factors comprise one of the most important classes of enhancer-type transcription factors. They act in networks of homo and heterodimers in the regulation of a diverse set of cellular processes including cell survival, learning and memory, lipid metabolism, and cancer progression, among others. They also play important roles in responses to stimuli or stress signals such as cytokines, genotoxic agents, or physiological stresses. The bZIP structural motif contains a basic region and a leucine zipper, composed of alpha helices with leucine residues 7 amino acids apart, which stabilize dimerization with a parallel leucine zipper domain. Dimerization of leucine zippers creates a pair of the adjacent basic regions that bind DNA and undergo conformational change. Dimerization occurs in a specific and predictable manner resulting in hundreds of dimers having unique effects on transcription.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|....*..
gi 808355254 287 RRKIKNKLSAQESRRKRKEYIDALEgrlhcfsEENKSLKKQVHQLEASNRDLQQKLH 343
Cdd:cd14686    3 RRRERNREAARRSRERKKERIEELE-------EEVEELEEENEELKAELEELRAEVE 52

Basic leucine zipper (bZIP) domain of Cyclic AMP-responsive element-binding protein 1 (CREB1) and similar proteins: a DNA-binding and dimerization domain; CREB1 is a Basic leucine zipper (bZIP) transcription factor that plays a role in propagating signals initiated by receptor activation through the induction of cAMP-responsive genes. Because it responds to many signal transduction pathways, CREB1 is implicated to function in many processes including learning, memory, circadian rhythm, immune response, and reproduction, among others. bZIP factors act in networks of homo and heterodimers in the regulation of a diverse set of cellular processes. The bZIP structural motif contains a basic region and a leucine zipper, composed of alpha helices with leucine residues 7 amino acids apart, which stabilize dimerization with a parallel leucine zipper domain. Dimerization of leucine zippers creates a pair of the adjacent basic regions that bind DNA and undergo conformational change. Dimerization occurs in a specific and predictable manner resulting in hundreds of dimers having unique effects on transcription.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|..
gi 808355254 287 RRKIKNKLSAQESRRKRKEYIDALEGRLHCFSEENKSLKKQV 328
Cdd:cd14690    4 LRLEKNREAARECRRKKKEYVKCLENRVAVLENENKELREEL 45

Basic leucine zipper (bZIP) domain of bZIP transcription factors: a DNA-binding and dimerization domain; uncharacterized subfamily; Basic leucine zipper (bZIP) factors comprise one of the most important classes of enhancer-type transcription factors. They act in networks of homo and heterodimers in the regulation of a diverse set of cellular processes including cell survival, learning and memory, lipid metabolism, and cancer progression, among others. They also play important roles in responses to stimuli or stress signals such as cytokines, genotoxic agents, or physiological stresses. The bZIP structural motif contains a basic region and a leucine zipper, composed of alpha helices with leucine residues 7 amino acids apart, which stabilize dimerization with a parallel leucine zipper domain. Dimerization of leucine zippers creates a pair of the adjacent basic regions that bind DNA and undergo conformational change. Dimerization occurs in a specific and predictable manner resulting in hundreds of dimers having unique effects on transcription.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|....*....
gi 808355254 287 RRKIKNKLSAQESRRKRKEYIDALEGRLHCFSEENKSLKKQVHQLEASN 335
Cdd:cd14810    3 KRQLRNKISARNFRARRKEYITQLEEQVADRDAEIEQLRAELRALRNEN 51

Basic leucine zipper (bZIP) domain of Activating Transcription Factor-2 (ATF-2) and similar proteins: a DNA-binding and dimerization domain; ATF-2 is a sequence-specific DNA-binding protein that belongs to the Basic leucine zipper (bZIP) family of transcription factors. In response to stress, it activates a variety of genes including cyclin A, cyclin D, and c-Jun. ATF-2 also plays a role in the DNA damage response that is independent of its transcriptional activity. bZIP factors act in networks of homo and heterodimers in the regulation of a diverse set of cellular processes. The bZIP structural motif contains a basic region and a leucine zipper, composed of alpha helices with leucine residues 7 amino acids apart, which stabilize dimerization with a parallel leucine zipper domain. Dimerization of leucine zippers creates a pair of the adjacent basic regions that bind DNA and undergo conformational change. Dimerization occurs in a specific and predictable manner resulting in hundreds of dimers having unique effects on transcription.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|....*...
gi 808355254 287 RRKI--KNKLSAQESRRKRKEYIDALEGRLHCFSEENKSLKKQVHQLEASNRDLQQKL 342
Cdd:cd14687    2 RKRFleRNRIAASKCRQRKKQWVQQLEEKVRKLESENKALKAEVDKLREEVLDLKNLL 59

Basic leucine zipper (bZIP) domain of bZIP transcription factors: a DNA-binding and dimerization domain; uncharacterized subfamily; Basic leucine zipper (bZIP) factors comprise one of the most important classes of enhancer-type transcription factors. They act in networks of homo and heterodimers in the regulation of a diverse set of cellular processes including cell survival, learning and memory, lipid metabolism, and cancer progression, among others. They also play important roles in responses to stimuli or stress signals such as cytokines, genotoxic agents, or physiological stresses. The bZIP structural motif contains a basic region and a leucine zipper, composed of alpha helices with leucine residues 7 amino acids apart, which stabilize dimerization with a parallel leucine zipper domain. Dimerization of leucine zippers creates a pair of the adjacent basic regions that bind DNA and undergo conformational change. Dimerization occurs in a specific and predictable manner resulting in hundreds of dimers having unique effects on transcription.

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|.
gi 808355254 287 RRKIKNKLSAQESRRKRKEYIDALEGRlhcfseenkslkkqVHQLEASNRDLQQKLHQYES 347
Cdd:cd14812    3 ARLIRNRAAAQLSRQRKKEEVEELEAR--------------VKELEAENRRLRQLLAQPEA 49

Basic region leucine zipper;

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*..
gi 808355254  287 RRKIKNKLSAQESRRKRKEYIDALEGRLHCFSEENKSLKKQVHQLEA 333
Cdd:pfam07716   4 DRRRKNNEAAKRSREKKKQKEEELEERVKELERENAQLRQKVEQLEK 50

Basic leucine zipper (bZIP) domain of Activating Transcription Factor-4 (ATF-4) and similar proteins: a DNA-binding and dimerization domain; ATF-4 was also isolated and characterized as the cAMP-response element binding protein 2 (CREB2). It is a Basic leucine zipper (bZIP) transcription factor that has been reported to act as both an activator or repressor. It is a critical component in both the unfolded protein response (UPR) and amino acid response (AAR) pathways. Under certain stress conditions, ATF-4 transcription is increased; accumulation of ATF-4 induces the expression of genes involved in amino acid metabolism and transport, mitochondrial function, redox chemistry, and others that ensure protein synthesis and recovery from stress. bZIP factors act in networks of homo and heterodimers in the regulation of a diverse set of cellular processes. The bZIP structural motif contains a basic region and a leucine zipper, composed of alpha helices with leucine residues 7 amino acids apart, which stabilize dimerization with a parallel leucine zipper domain. Dimerization of leucine zippers creates a pair of the adjacent basic regions that bind DNA and undergo conformational change. Dimerization occurs in a specific and predictable manner resulting in hundreds of dimers having unique effects on transcription.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|....*.
gi 808355254 287 RRKIKNKLSAQESRRKRKEYIDALEGRLHCFSEENKSLKKQVHQLE 332
Cdd:cd14692    5 RKREQNKNAATRYRQKKREEKEELLSEEEELEDRNRELKDEVEELQ 50

Basic leucine zipper (bZIP) domain of Plant G-box binding factor 1 (GBF1)-like transcription factors: a DNA-binding and dimerization domain; This subfamily is composed of plant bZIP transciption factors including Arabidopsis thaliana G-box binding factor 1 (GBF1), Zea mays Opaque-2 and Ocs element-binding factor 1 (OCSBF-1), Triticum aestivum Histone-specific transcription factor HBP1 (or HBP-1a), Petroselinum crispum Light-inducible protein CPRF3 and CPRF6, and Nicotiana tabacum BZI-3, among many others. bZIP G-box binding factors (GBFs) contain an N-terminal proline-rich domain in addition to the bZIP domain. GBFs are involved in developmental and physiological processes in response to stimuli such as light or hormones. Opaque-2 plays a role in affecting lysine content and carbohydrate metabolism, acting indirectly on starch/amino acid ratio. bZIP factors act in networks of homo and heterodimers in the regulation of a diverse set of cellular processes. The bZIP structural motif contains a basic region and a leucine zipper, composed of alpha helices with leucine residues 7 amino acids apart, which stabilize dimerization with a parallel leucine zipper domain. Dimerization of leucine zippers creates a pair of the adjacent basic regions that bind DNA and undergo conformational change. Dimerization occurs in a specific and predictable manner resulting in hundreds of dimers having unique effects on transcription.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|....*.
gi 808355254 287 RRKIKNKLSAQESRRKRKEYIDALEGRLHCFSEENKSLKKQVHQLE 332
Cdd:cd14702    3 RRKQSNRESARRSRMRKQAHLEELEAQVEQLRAENSTLRAELNALS 48

Basic leucine zipper (bZIP) domain of BTB and CNC homolog (BACH) proteins: a DNA-binding and dimerization domain; BACH proteins are Cap'n'Collar (CNC) Basic leucine zipper (bZIP) transcription factors that are defined by a conserved 43-amino acid region (called the CNC domain) located N-terminal to the bZIP DNA-binding domain. In addition, they contain a BTB domain (Broad complex-Tramtrack-Bric-a-brac domain, also known as the POZ [poxvirus and zinc finger] domain) that is absent in other CNC proteins. Veterbrates contain two members, BACH1 and BACH2. BACH1 forms heterodimers with small Mafs such as MafK to function as a repressor of heme oxygenase-1 (HO-1) gene (Hmox-1) enhancers. It has also been implicated as the master regulator of breast cancer bone metastasis. The BACH1 bZIP transcription factor should not be confused with the protein originally named as BRCA1-Associated C-terminal Helicase1 (BACH1), which has been renamed BRIP1 (BRCA1 Interacting Protein C-terminal Helicase1) and also called FANCJ. BACH2 is a B-cell specific transcription factor that plays a critical role in oxidative stress-mediated apoptosis. It plays an important role in class switching and somatic hypermutation of immunoglobulin genes. bZIP factors act in networks of homo and heterodimers in the regulation of a diverse set of cellular processes. The bZIP structural motif contains a basic region and a leucine zipper, composed of alpha helices with leucine residues 7 amino acids apart, which stabilize dimerization with a parallel leucine zipper domain. Dimerization of leucine zippers creates a pair of the adjacent basic regions that bind DNA and undergo conformational change. Dimerization occurs in a specific and predictable manner resulting in hundreds of dimers having unique effects on transcription.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|....*..
gi 808355254 286 VRRKIKNKLSAQESRRKRKEYIDALEGRLHCFSEENKSLKKQVHQLEASNRDLQQKL 342
Cdd:cd14719   11 VRRRSKNRIAAQRCRKRKLDCIQNLECEIKKLVCEKEKLLGERNQLKASMGELRENF 67

Basic leucine zipper (bZIP) domain of Cyclic AMP-responsive element-binding protein-like 2 (CREBL2): a DNA-binding and dimerization domain; CREBL2 is a bZIP transcription factor that interacts with CREB and plays a critical role in adipogenesis and lipogenesis. Its overexpression upregulates the expression of PPARgamma and CEBPalpha to promote adipogenesis as well as accelerate lipogenesis by increasing GLUT1 and GLUT4. bZIP factors act in networks of homo and heterodimers in the regulation of a diverse set of cellular processes. The bZIP structural motif contains a basic region and a leucine zipper, composed of alpha helices with leucine residues 7 amino acids apart, which stabilize dimerization with a parallel leucine zipper domain. Dimerization of leucine zippers creates a pair of the adjacent basic regions that bind DNA and undergo conformational change. Dimerization occurs in a specific and predictable manner resulting in hundreds of dimers having unique effects on transcription.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|....*
gi 808355254 284 KIVRRKIKNKLSAQESRRKRKEYIDALEGRLHCFSEENKSLKKQVHQLEASNRDL 338
Cdd:cd14709    1 KKKAKLERNRQSARESRDRKKLRYQYLEQLVADREREILLLREELEMYKQWCEEL 55

Basic leucine zipper (bZIP) domain of small musculoaponeurotic fibrosarcoma (Maf) proteins: a DNA-binding and dimerization domain; Maf proteins are Basic leucine zipper (bZIP) transcription factors that may participate in the activator protein-1 (AP-1) complex, which is implicated in many cell functions including proliferation, apoptosis, survival, migration, tumorigenesis, and morphogenesis, among others. Maf proteins fall into two groups: small and large. The small Mafs (MafF, MafK, and MafG) do not contain a transactivation domain but do harbor the anxillary DNA-binding domain and a C-terminal bZIP domain. They form dimers with cap'n'collar (CNC) proteins that harbor transactivation domains, and they act either as activators or repressors depending on their dimerization partner. CNC transcription factors include NFE2 (nuclear factor, erythroid-derived 2) and similar proteins NFE2L1 (NFE2-like 1), NFE2L2, and NFE2L3, as well as BACH1 and BACH2. Small Mafs play roles in stress response and detoxification pathways. They also regulate the expression of betaA-globin and other genes activated during erythropoiesis. They have been implicated in various diseases such as diabetes, neurological diseases, thrombocytopenia and cancer. Triple deletion of the three small Mafs is embryonically lethal. bZIP factors act in networks of homo and heterodimers in the regulation of a diverse set of cellular processes. The bZIP structural motif contains a basic region and a leucine zipper, composed of alpha helices with leucine residues 7 amino acids apart, which stabilize dimerization with a parallel leucine zipper domain. Dimerization of leucine zippers creates a pair of the adjacent basic regions that bind DNA and undergo conformational change. Dimerization occurs in a specific and predictable manner resulting in hundreds of dimers having unique effects on transcription.

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 808355254 277 KSEEESLKIVRRKIKNKLSAQESRRKRKEYIDALEGrlhcfseENKSLKKQVHQLEASNRDLQQKLHQYESK 348
Cdd:cd14717    1 KEEIIRLKQRRRTLKNRGYAASCRIKRVTQKEELEK-------QKAELQQEVEKLARENASMRLELDALRSK 65

Basic leucine zipper (bZIP) domain of Nuclear Factor, Erythroid-derived 2 (NFE2) and similar proteins: a DNA-binding and dimerization domain; This subfamily is composed of NFE2 and NFE2-like proteins including NFE2-like 1 or NFE2-related factor 1 (NFE2L1 or Nrf1), NFE2L2 (or Nrf2), and NFE2L3 (or Nrf3). These are Cap'n'Collar (CNC) Basic leucine zipper (bZIP) transcription factors that are defined by a conserved 43-amino acid region (called the CNC domain) located N-terminal to the bZIP DNA-binding domain. NFE2 functions in development; it is required for the proper development of platelets. The three Nrfs function in stress responses. Nrf2, the most extensively studied member of this subfamily, acts as a xenobiotic-activated receptor that regulates the adaptive response to oxidants and electrophiles. As the master regulator of the antioxidant defense pathway, it plays roles in the biology of inflammation, obesity, and cancer. Nrf1 is an essential protein that binds to the antioxidant response element (ARE) and is also involved in regulating oxidative stress. In addition, it also regulates genes involved in cell and tissue differentiation, inflammation, and hepatocyte homeostasis. bZIP factors act in networks of homo and heterodimers in the regulation of a diverse set of cellular processes. The bZIP structural motif contains a basic region and a leucine zipper, composed of alpha helices with leucine residues 7 amino acids apart, which stabilize dimerization with a parallel leucine zipper domain. Dimerization of leucine zippers creates a pair of the adjacent basic regions that bind DNA and undergo conformational change. Dimerization occurs in a specific and predictable manner resulting in hundreds of dimers having unique effects on transcription.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|....*....
gi 808355254 286 VRRKIKNKLSAQESRRKRKEYIDALEGRLHCFSEENKSLKKQVHQLEASNRDLQQKLHQ 344
Cdd:cd14720    8 IRRRGKNKVAAQNCRKRKLDNIVGLEDEVEQLQRQREKLLREKAENAKSLREMKQKLND 66

Basic leucine zipper (bZIP) domain of large musculoaponeurotic fibrosarcoma (Maf) proteins: a DNA-binding and dimerization domain; Maf proteins are Basic leucine zipper (bZIP) transcription factors that may participate in the activator protein-1 (AP-1) complex, which is implicated in many cell functions including proliferation, apoptosis, survival, migration, tumorigenesis, and morphogenesis, among others. Maf proteins fall into two groups: small and large. The large Mafs (c-Maf, MafA, MafB, and neural retina leucine zipper or NRL) contain an N-terminal transactivation domain, a linker region of varying size, an anxillary DNA-binding domain, a C-terminal bZIP domain. They function as critical regulators of terminal differentiation in the blood and in many tissues such as bone, brain, kidney, pancreas, and retina. MafA and MafB also play crucial roles in islet beta cells; they regulate genes essential for glucose sensing and insulin secretion cooperatively and sequentially. Large Mafs are also implicated in oncogenesis; MafB and c-Maf chromosomal translocations result in multiple myelomas. bZIP factors act in networks of homo and heterodimers in the regulation of a diverse set of cellular processes. The bZIP structural motif contains a basic region and a leucine zipper, composed of alpha helices with leucine residues 7 amino acids apart, which stabilize dimerization with a parallel leucine zipper domain. Dimerization of leucine zippers creates a pair of the adjacent basic regions that bind DNA and undergo conformational change. Dimerization occurs in a specific and predictable manner resulting in hundreds of dimers having unique effects on transcription.

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                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 808355254 277 KSEEESLKIVRRKIKNKLSAQESRRKRKEYIDALEgrlhcfsEENKSLKKQVHQLEASNRDLQQKLHQYESK 348
Cdd:cd14718    1 KEEVIRLKQKRRTLKNRGYAQSCRSKRVQQRHVLE-------SEKCQLQQQVEQLKQEVSRLARERDAYKEK 65

Basic leucine zipper (bZIP) domain of blue light (BL) receptor aureochrome (AUREO) and similar bZIP domains; AUREO is a BL-activated transcription factor specific to phototrophic stramenopiles. It has a bZIP and a BL-sensing light-oxygen voltage (LOV) domain. It has been shown to mediate BL-induced branching and regulate the development of the sex organ in Vaucheria frigida. bZIP factors act in networks of homo and heterodimers in the regulation of a diverse set of cellular processes. The bZIP structural motif contains a basic region and a leucine zipper, composed of alpha helices with leucine residues 7 amino acids apart, which stabilize dimerization with a parallel leucine zipper domain. Dimerization of leucine zippers creates a pair of the adjacent basic regions that bind DNA and undergo conformational change. Dimerization occurs in a specific and predictable manner resulting in hundreds of dimers having unique effects on transcription. This subgroup also includes the Epstein-Barr virus (EBV) immediate-early transcription factor ZEBRA (BZLF1, Zta, Z, EB1). ZEBRA exhibits a variant of the bZIP fold, it has a unique dimer interface and a substantial hydrophobic pocket; it has a C-terminal moiety which stabilizes the coiled coil involved in dimer formation. ZEBRA functions to trigger the switch of EBV's biphasic infection cycle from latent to lytic infection. It activates the promoters of EBV lytic genes by binding ZEBRA response elements (ZREs) and inducing a cascade of expression of over 50 viral genes. It also down regulates latency-associated promoters, is an essential replication factor, induces host cell cycle arrest, and alters cellular immune responses and transcription factor activity.

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                 ....*....|....*....|....*....|....*....|....*....|....*.
gi 808355254 287 RRKIKNKLSAQESRRKRKEYIdalegrlhcfseenKSLKKQVHQLEASNRDLQQKL 342
Cdd:cd14809    3 RRRERNREHARKTRLRKKAYL--------------ESLKEQVAALQAENQRLRQQI 44