Basic leucine zipper (bZIP) domain of Nuclear factor interleukin-3-regulated protein (NFIL3): a DNA-binding and dimerization domain; NFIL3, also called E4 promoter-binding protein 4 (E4BP4), is a Basic leucine zipper (bZIP) transcription factor that was independently identified as a transactivator of the IL3 promoter in T-cells and as a transcriptional repressor that binds to a DNA sequence site in the adenovirus E4 promoter. Its expression levels are regulated by cytokines and it plays crucial functions in the immune system. It is required for the development of natural killer cells and CD8+ conventional dendritic cells. In B-cells, NFIL3 mediates immunoglobulin heavy chain class switching that is required for IgE production, thereby influencing allergic and pathogenic immune responses. It is also involved in the polarization of T helper responses. 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 17534989  53 KDEHYWERRRRNNDASRRSREKRRQNDLAMEEKIMLLSAENERLKSQL 100
Cdd:cd14694   1 KDDKYWEKRRKNNEAAKRSREKRRLNDLVLENRILELTEENAVLRAEL 48

Basic leucine zipper (bZIP) domain of Nuclear factor interleukin-3-regulated protein (NFIL3): a DNA-binding and dimerization domain; NFIL3, also called E4 promoter-binding protein 4 (E4BP4), is a Basic leucine zipper (bZIP) transcription factor that was independently identified as a transactivator of the IL3 promoter in T-cells and as a transcriptional repressor that binds to a DNA sequence site in the adenovirus E4 promoter. Its expression levels are regulated by cytokines and it plays crucial functions in the immune system. It is required for the development of natural killer cells and CD8+ conventional dendritic cells. In B-cells, NFIL3 mediates immunoglobulin heavy chain class switching that is required for IgE production, thereby influencing allergic and pathogenic immune responses. It is also involved in the polarization of T helper responses. 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 17534989  53 KDEHYWERRRRNNDASRRSREKRRQNDLAMEEKIMLLSAENERLKSQL 100
Cdd:cd14694   1 KDDKYWEKRRKNNEAAKRSREKRRLNDLVLENRILELTEENAVLRAEL 48

basic region leucin zipper;

                           10        20        30        40        50        60
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 17534989    327 NKSPQYVDRRRRNNEAAKRCRANRRAVFEYRSRRVQLLEGENEDLRTQIETLKAEIAHFKSVLAQ 391
Cdd:smart00338   1 EEDEKRRRRRERNREAARRSRERKKAEIEELERKVEQLEAENERLKKEIERLRRELEKLKSELEE 65

Basic region leucine zipper;

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|.
gi 17534989   331 QYVDRRRRNNEAAKRCRANRRAVFEYRSRRVQLLEGENEDLRTQIETLKAE 381
Cdd:pfam07716   1 EYRDRRRKNNEAAKRSREKKKQKEEELEERVKELERENAQLRQKVEQLEKE 51

Basic leucine zipper (bZIP) domain of Nuclear factor interleukin-3-regulated protein (NFIL3): a DNA-binding and dimerization domain; NFIL3, also called E4 promoter-binding protein 4 (E4BP4), is a Basic leucine zipper (bZIP) transcription factor that was independently identified as a transactivator of the IL3 promoter in T-cells and as a transcriptional repressor that binds to a DNA sequence site in the adenovirus E4 promoter. Its expression levels are regulated by cytokines and it plays crucial functions in the immune system. It is required for the development of natural killer cells and CD8+ conventional dendritic cells. In B-cells, NFIL3 mediates immunoglobulin heavy chain class switching that is required for IgE production, thereby influencing allergic and pathogenic immune responses. It is also involved in the polarization of T helper responses. 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 17534989  53 KDEHYWERRRRNNDASRRSREKRRQNDLAMEEKIMLLSAENERLKSQL 100
Cdd:cd14694   1 KDDKYWEKRRKNNEAAKRSREKRRLNDLVLENRILELTEENAVLRAEL 48

Basic leucine zipper (bZIP) domain of Hepatic leukemia factor (HLF) and similar proteins: a DNA-binding and dimerization domain; HLF, also called vitellogenin gene-binding protein (VBP) in birds, is a circadian clock-controlled Basic leucine zipper (bZIP) transcription factor which is a direct transcriptional target of CLOCK/BMAL1. It is implicated, together with bZIPs DBP and TEF, in the regulation of genes involved in the metabolism of endobiotic and xenobiotic agents. Triple knockout mice display signs of early aging and suffer premature death, likely due to impaired defense against xenobiotic stress. A leukemogenic translocation results in the chimeric fusion protein E2A-HLF that results in a rare form of pro-B-cell acute lymphoblastic leukemia (ALL). 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 17534989  53 KDEHYWERRRRNNDASRRSREKRRQNDLAMEEKIMLLSAENERLKSQL 100
Cdd:cd14695   1 KDDKYWERRRKNNLAAKRSRDARRLKENQIAIRAAFLEKENAALRAEI 48

Basic region leucine zipper;

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....
gi 17534989    57 YWERRRRNNDASRRSREKRRQNDLAMEEKIMLLSAENERLKSQL 100
Cdd:pfam07716   2 YRDRRRKNNEAAKRSREKKKQKEEELEERVKELERENAQLRQKV 45

Basic leucine zipper (bZIP) domain of CCAAT/enhancer-binding protein (CEBP) and similar proteins: a DNA-binding and dimerization domain; CEBPs (or C/EBPs) are Basic leucine zipper (bZIP) transcription factors that regulate the cell cycle, differentiation, growth, survival, energy metabolism, innate and adaptive immunity, and inflammation, among others. They are also associated with cancer and viral disease. There are six CEBP proteins in mammalian cells including CEBPA (alpha), CEBPB (beta), CEBPG (gamma), CEBPD (delta), and CEBPE (epsilon), which all contain highly conserved bZIP domains at their C-termini and variations at their N-terminal regions. Each possesses unique properties to regulate cell type-specific growth and differentiation. The sixth isoform, CEBPZ (zeta), lacks an intact DNA-binding domain and is excluded from this subfamily. 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 17534989  54 DEHYWERRRRNNDASRRSREKRRQNDLAMEEKIMLLSAENERLKSQL 100
Cdd:cd14693   2 SEEYRQKRERNNIAVRKSREKAKQRQLETQQKVQELRKENERLQKRV 48

Basic leucine zipper (bZIP) domain of Bombyx mori chorion b-ZIP transcription factor and similar bZIP domains; Bombyx mori chorion b-ZIP transcription factor, is encoded by the Cbz gene. 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 17534989  57 YWERRRRNNDASRRSREKRRQNDLAMEEKIMLLSAENERLKSQL 100
Cdd:cd14813   1 YREKRDKNNEASRRSRLNRKQKEQEMQKEAEELERENEALKVKV 44

Basic leucine zipper (bZIP) domain of CCAAT/enhancer-binding protein (CEBP) and similar proteins: a DNA-binding and dimerization domain; CEBPs (or C/EBPs) are Basic leucine zipper (bZIP) transcription factors that regulate the cell cycle, differentiation, growth, survival, energy metabolism, innate and adaptive immunity, and inflammation, among others. They are also associated with cancer and viral disease. There are six CEBP proteins in mammalian cells including CEBPA (alpha), CEBPB (beta), CEBPG (gamma), CEBPD (delta), and CEBPE (epsilon), which all contain highly conserved bZIP domains at their C-termini and variations at their N-terminal regions. Each possesses unique properties to regulate cell type-specific growth and differentiation. The sixth isoform, CEBPZ (zeta), lacks an intact DNA-binding domain and is excluded from this subfamily. 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 17534989 329 SPQYVDRRRRNNEAAKRCRANRRAVFEYRSRRVQLLEGENEDLRTQIETLKAEIAHFKS 387
Cdd:cd14693   2 SEEYRQKRERNNIAVRKSREKAKQRQLETQQKVQELRKENERLQKRVELLTKELSVLKS 60

Basic leucine zipper (bZIP) domain of Bombyx mori chorion b-ZIP transcription factor and similar bZIP domains; Bombyx mori chorion b-ZIP transcription factor, is encoded by the Cbz gene. 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 17534989 332 YVDRRRRNNEAAKRCRANRRAVFEYRSRRVQLLEGENEDLRTQIETLKAEIA 383
Cdd:cd14813   1 YREKRDKNNEASRRSRLNRKQKEQEMQKEAEELERENEALKVKVEELEKELK 52

Basic leucine zipper (bZIP) domain of Nuclear factor interleukin-3-regulated protein (NFIL3): a DNA-binding and dimerization domain; NFIL3, also called E4 promoter-binding protein 4 (E4BP4), is a Basic leucine zipper (bZIP) transcription factor that was independently identified as a transactivator of the IL3 promoter in T-cells and as a transcriptional repressor that binds to a DNA sequence site in the adenovirus E4 promoter. Its expression levels are regulated by cytokines and it plays crucial functions in the immune system. It is required for the development of natural killer cells and CD8+ conventional dendritic cells. In B-cells, NFIL3 mediates immunoglobulin heavy chain class switching that is required for IgE production, thereby influencing allergic and pathogenic immune responses. It is also involved in the polarization of T helper responses. 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 17534989 328 KSPQYVDRRRRNNEAAKRCRANRRAVFEYRSRRVQLLEGENEDLRTQIETLK 379
Cdd:cd14694   1 KDDKYWEKRRKNNEAAKRSREKRRLNDLVLENRILELTEENAVLRAELAALK 52

Basic leucine zipper (bZIP) domain of the oncogene Fos (Fos)-like transcription factors: a DNA-binding and dimerization domain; This subfamily is composed of Fos proteins (c-Fos, FosB, Fos-related antigen 1 (Fra-1), and Fra-2), Activating Transcription Factor-3 (ATF-3), and similar proteins. Fos proteins are members of the activator protein-1 (AP-1) complex, which is mainly composed of bZIP dimers of the Jun and Fos families, and to a lesser extent, ATF and musculoaponeurotic fibrosarcoma (Maf) families. The broad combinatorial possibilities for various dimers determine binding specificity, affinity, and the spectrum of regulated genes. The AP-1 complex is implicated in many cell functions including proliferation, apoptosis, survival, migration, tumorigenesis, and morphogenesis, among others. ATF3 is induced by various stress signals such as cytokines, genotoxic agents, or physiological stresses. It is implicated in cancer and host defense against pathogens. It negatively regulates the transcription of pro-inflammatory cytokines and is critical in preventing acute inflammatory syndromes. ATF3 dimerizes with Jun and other ATF proteins; the heterodimers function either as activators or repressors depending on the promoter context. 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 17534989 335 RRRRNNEAAKRCRANRRAVFEYRSRRVQLLEGENEDLRTQIETLKAEIAHFKSVL 389
Cdd:cd14699   5 RRERNKVAAAKCRQRRRELMEELQAEVEQLEDENEKLQSEIANLRSEKEQLEELL 59

Basic leucine zipper (bZIP) domain of Fungal Zip1-like transcription factors: a DNA-binding and dimerization domain; This subfamily is composed of fungal bZIP transcription factors including Schizosaccharomyces pombe Zip1, Saccharomyces cerevisiae Methionine-requiring protein 28 (Met28p), and Neurospora crassa cys-3, among others. Zip1 is required for the production of key proteins involved in sulfur metabolism and also plays a role in cadmium response. Met28p acts as a cofactor of Met4p, a transcriptional activator of the sulfur metabolic network; it stabilizes DNA:Met4 complexes. 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 17534989 334 DRRRRNNEAAKRCRANRRAVFEYRSRRVQLLEGENEDLRTQIETLKAEIAHFK 386
Cdd:cd14705   3 EKRRRNTAASARFRAKKKQREQELEEKLKELEERIKELERRLDELESENKFLK 55

Basic leucine zipper (bZIP) domain of CCAAT/enhancer-binding protein gamma (CEBPG): a DNA-binding and dimerization domain; CEBPG is an important regulator of cellular senescence; mouse embryonic fibroblasts deficient of CEBPG proliferated poorly, entered senescence prematurely, and expressed elevated levels of proinflammatory genes. It is also the primary transcription factor that regulates antioxidant and DNA repair transcripts in normal bronchial epithelial cells. In a subset of AML patients with CEBPA hypermethylation, CEBPG is significantly overexpressed. CEBPG is the shortest CEBP protein and it lacks a transactivation domain. It acts as a regulator and buffering reservoir against the transcriptional activities of other CEBP proteins. CEBPs (or C/EBPs) are Basic leucine zipper (bZIP) transcription factors that regulate many cellular processes. There are six CEBP proteins in mammalian cells including CEBPA (alpha), CEBPB (beta), CEBPG (gamma), CEBPD (delta), and CEBPE (epsilon), which all contain highly conserved bZIP domains at their C-termini and variations at their N-terminal regions. 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 17534989  55 EHYWERRRRNNDASRRSREKRRQNDLAMEEKIMLLSAENERL 96
Cdd:cd14713   4 DEYRKRRERNNLAVKKSREKSKQKAQETLQRVNQLKEENERL 45

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        50
                ....*....|....*....|....*....|....*....|....*....|.
gi 17534989 335 RRRRNNEAAKRCRANRRAVFEYRSRRVQLLEGENEDLRTQIETLKAEIAHF 385
Cdd:cd14690   5 RLEKNREAARECRRKKKEYVKCLENRVAVLENENKELREELKILKELLCQE 55

Basic leucine zipper (bZIP) domain of Fungal Zip1-like transcription factors: a DNA-binding and dimerization domain; This subfamily is composed of fungal bZIP transcription factors including Schizosaccharomyces pombe Zip1, Saccharomyces cerevisiae Methionine-requiring protein 28 (Met28p), and Neurospora crassa cys-3, among others. Zip1 is required for the production of key proteins involved in sulfur metabolism and also plays a role in cadmium response. Met28p acts as a cofactor of Met4p, a transcriptional activator of the sulfur metabolic network; it stabilizes DNA:Met4 complexes. 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 17534989  59 ERRRRNNDASRRSREKRRQNDLAMEEKIMLLSAENERLKSQL 100
Cdd:cd14705   3 EKRRRNTAASARFRAKKKQREQELEEKLKELEERIKELERRL 44

Basic leucine zipper (bZIP) domain of CCAAT/enhancer-binding protein alpha (CEBPA): a DNA-binding and dimerization domain; CEPBA is a critical regulator of myeloid development; it directs granulocyte and monocyte differentiation. It is highly expressed in early myeloid progenitors and is found mutated in over half of patients with acute myeloid leukemia (AML). It is also a key regulator in energy homeostasis; mice deficient of CEBPA show abnormalities in glycogen/lipid synthesis and storage. CEPBA is the longest CEBP protein containing two transactivation domains at the N-terminus followed by a regulatory domain, a bZIP domain, and C-terminal tail. CEBPs (or C/EBPs) are Basic leucine zipper (bZIP) transcription factors that regulate many cellular processes. There are six CEBP proteins in mammalian cells including CEBPA (alpha), CEBPB (beta), CEBPG (gamma), CEBPD (delta), and CEBPE (epsilon), which all contain highly conserved bZIP domains at their C-termini and variations at their N-terminal regions. 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 17534989  57 YWERRRRNNDASRRSREKRRQNDLAMEEKIMLLSAENERLKSQL 100
Cdd:cd14711   6 YRVRRERNNIAVRKSRDKAKQRNVETQQKVLELTSDNDRLRKRV 49

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.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|...
gi 17534989 335 RRRRNNEAAKRCRANRRAVFEYRSRRVQLLEGENEDLRTQIET 377
Cdd:cd14809   4 RRERNREHARKTRLRKKAYLESLKEQVAALQAENQRLRQQIRQ 46

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
                ....*....|....*....|....*....|....*....|....
gi 17534989 338 RNNEAAKRCRANRRAVFEYRSRRVQLLEGENEDLRTQIETLKAE 381
Cdd:cd14709   8 RNRQSARESRDRKKLRYQYLEQLVADREREILLLREELEMYKQW 51

Basic leucine zipper (bZIP) domain of Activating Transcription Factor-3 (ATF-3) and similar proteins: a DNA-binding and dimerization domain; ATF-3 is a Basic leucine zipper (bZIP) transcription factor that is induced by various stress signals such as cytokines, genetoxic agents, or physiological stresses. It is implicated in cancer and host defense against pathogens. It negatively regulates the transcription of pro-inflammatory cytokines and is critical in preventing acute inflammatory syndromes. Mice deficient with ATF3 display increased susceptibility to endotoxic shock induced death. ATF3 dimerizes with Jun and other ATF proteins; the heterodimers function either as activators or repressors depending on the promoter context. 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 17534989 335 RRRRNNEAAKRCRANRRAVFEYRSRRVQLLEGENEDLRTQIETLKAEIAHFKSVLA 390
Cdd:cd14722   5 RRERNKVAAAKCRNKKKERTDCLQKESEKLETQNAELKRQIEELKNEKQHLIDMLN 60

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.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*...
gi 17534989 335 RRRRNNEAAKRCRANRRAVFEYRSRRVQLLEGENEDLRTQIETLKAEI 382
Cdd:cd14691   7 RKLKNRVAAQTARDRKKARMDELEERVRELEEENQKLRAENESLRARN 54

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

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|...
gi 17534989    60 RRRRNNDASRRSREKRRQNDLAMEEKIMLLSAENERLKSQLGT 102
Cdd:pfam00170   5 RKQSNREAARRSRQRKQAYIEELERRVKALEGENKTLRSELEE 47

Basic leucine zipper (bZIP) domain of CCAAT/enhancer-binding protein epsilon (CEBPE): a DNA-binding and dimerization domain; CEBPE is a critical regulator of terminal granulocyte differentiation or granulopoiesis. It is expressed only in myeloid cells. Mice deficient with CEBPE are normal at birth and fertile, but they do not produce normal neutrophils or eosinophils, and show impaired inflammatory and bacteriocidal responses. Functional loss of CEBPE causes the rare congenital disorder, Neutrophil-specific granule deficiency (SGD), which is characterized by patients' neutrophils with atypical nuclear morphology, abnormal migration and bactericidal activity, and the lack of specific granules. Patients with SGD suffer from severe and frequent bacterial infections. CEBPs (or C/EBPs) are Basic leucine zipper (bZIP) transcription factors that regulate many cellular processes. There are six CEBP proteins in mammalian cells including CEBPA (alpha), CEBPB (beta), CEBPG (gamma), CEBPD (delta), and CEBPE (epsilon), which all contain highly conserved bZIP domains at their C-termini and variations at their N-terminal regions. 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 17534989 329 SPQYVDRRRRNNEAAKRCRAN-RRAVFEYRSRRVQLLeGENEDLRTQIETLKAEI 382
Cdd:cd14715   3 SLEYRLRRERNNIAVRKSRDKaKRRVLETQQRMLEYM-AENERLRSRVEQLTQEL 56

Basic leucine zipper (bZIP) domain of Jun proteins and similar proteins: a DNA-binding and dimerization domain; Jun is a member of the activator protein-1 (AP-1) complex, which is mainly composed of Basic leucine zipper (bZIP) dimers of the Jun and Fos families, and to a lesser extent, the activating transcription factor (ATF) and musculoaponeurotic fibrosarcoma (Maf) families. The broad combinatorial possibilities for various dimers determine binding specificity, affinity, and the spectrum of regulated genes. The AP-1 complex is implicated in many cell functions including proliferation, apoptosis, survival, migration, tumorigenesis, and morphogenesis, among others. There are three Jun proteins: c-Jun, JunB, and JunD. c-Jun is the most potent transcriptional activator of the AP-1 proteins. Both c-Jun and JunB are essential during development; deletion of either results in embryonic lethality in mice. c-Jun is essential in hepatogenesis and liver erythropoiesis, while JunB is required in vasculogenesis and angiogenesis in extraembryonic tissues. While JunD is dispensable in embryonic development, it is involved in transcription regulation of target genes that help cells to cope with environmental signals. 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 17534989 333 VDRRR-RNNEAAKRCRA---NRRAVFEyrsRRVQLLEGENEDLRTQIETLKAEIAHFKSVL 389
Cdd:cd14696   2 LERKRaRNRIAASKCRKrklERIARLE---DKVKELKNQNSELTSTASLLREQVCQLKQKV 59