basic region leucin zipper;

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                   ....*....|....*....|....*....|....*....|....*....|..
gi 71902536     96 NKIAAAKCRNKKKEKTECLQKESEKLESVNAELKAQIEELKNEKQHLIYMLN 147
Cdd:smart00338  13 NREAARRSRERKKAEIEELERKVEQLEAENERLKKEIERLRRELEKLKSELE 64

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.

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                ....*....|....*....|....*....|....*....|....*....|.
gi 71902536  96 NKIAAAKCRNKKKEKTECLQKESEKLESVNAELKAQIEELKNEKQHLIYML 146
Cdd:cd14699   9 NKVAAAKCRQRRRELMEELQAEVEQLEDENEKLQSEIANLRSEKEQLEELL 59

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.

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                ....*....|....*....|....*....|....*....|....*..
gi 71902536  96 NKIAAAKCRNKKKEKTECLQKESEKLESVNAELKAQIEELKNEKQHL 142
Cdd:cd14687   9 NRIAASKCRQRKKQWVQQLEEKVRKLESENKALKAEVDKLREEVLDL 55

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 71902536  96 NKIAAAKCRNKKKEKTECLQKESEKLESVNAELKAQIEELKNEKQHL 142
Cdd:cd14692  10 NKNAATRYRQKKREEKEELLSEEEELEDRNRELKDEVEELQREINYL 56

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 71902536  96 NKIAAAKCRNKKKEKTECLQKESEKLESVNAELKAQIEELKNEKQHL 142
Cdd:cd14705   8 NTAASARFRAKKKQREQELEEKLKELEERIKELERRLDELESENKFL 54

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 71902536  96 NKIAAAKCRNKKKEKTECLQKESEKLESVNAELKAQIEELKNEKQHL 142
Cdd:cd14691  11 NRVAAQTARDRKKARMDELEERVRELEEENQKLRAENESLRARNEDL 57

Basic leucine zipper (bZIP) domain of BATF proteins: a DNA-binding and dimerization domain; Basic leucine zipper (bZIP) transcription factor ATF-like (BATF or SFA2), BATF2 (or SARI) and BATF3 form heterodimers with Jun proteins. They function as inhibitors of AP-1-driven transcription. Unlike most bZIP transcription factors that contain additional domains, BATF and BATF3 contain only the the bZIP DNA-binding and dimerization domain. BATF2 contains an additional C-terminal domain of unknown function. BATF:Jun hetrodimers preferentially bind to TPA response elements (TREs) with the consensus sequence TGA(C/G)TCA, and can also bind to a TGACGTCA cyclic AMP response element (CRE). In addition to negative regulation, BATF proteins also show positive transcriptional activities in the development of classical dendritic cells and T helper cell subsets, and in antibody production. 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 71902536  96 NKIAAAKCRNKKKEKTECLQKESEKLESVNAELKAQIEELKNEKQHL 142
Cdd:cd14701  11 NRDAAQRSRQKQTEKADKLHEESESLERANAALRKEIKDLTEELKYL 57

Basic leucine zipper (bZIP) domain of General control protein GCN4: a DNA-binding and dimerization domain; GCN4 was identified in Saccharomyces cerevisiae from mutations in a deficiency in activation with the general amino acid control pathway. GCN4 encodes a trans-activator of amino acid biosynthetic genes containing 2 acidic activation domains and a C-terminal bZIP domain. In amino acid-deprived cells, GCN4 is up-regulated leading to transcriptional activation of genes encoding amino acid biosynthetic enzymes. 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 71902536  96 NKIAAAKCRNKKKEKTECLQKESEKLESVNAELKAQIEELKNEKQ 140
Cdd:cd12193  10 NTLAARRSRARKLEEMEELEKRVEELEAENEELKTRAEVLEAEAR 54

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.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*..
gi 71902536  96 NKIAAAKCRNKKKEKTECLQKESEKLESVNAELKAQIEELKNEKQHL 142
Cdd:cd14696   9 NRIAASKCRKRKLERIARLEDKVKELKNQNSELTSTASLLREQVCQL 55

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 71902536  96 NKIAAAKCRNKKKEKTECLQKESEKLESVNAELKAQIEELKNEKQHL 142
Cdd:cd14695  12 NNLAAKRSRDARRLKENQIAIRAAFLEKENAALRAEIAKLKKELEDL 58

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 71902536  96 NKIAAAKCRNKKKEKTECLQKESEKLESVNAELKAQIEELKNE 138
Cdd:cd14810   8 NKISARNFRARRKEYITQLEEQVADRDAEIEQLRAELRALRNE 50

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
                ....*....|....*....|....*....|....*..
gi 71902536  96 NKIAAAKCRNKKKEKTECLQKESEKLESVNAELKAQI 132
Cdd:cd14812   8 NRAAAQLSRQRKKEEVEELEARVKELEAENRRLRQLL 44