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 1972262718 325 RRNTILERNKAAAVRYRKRKKEEHDDMMGRVQAMEAEKNQLLV-----RNEILY 373
Cdd:cd14687     1 KRKRFLERNRIAASKCRQRKKQWVQQLEEKVRKLESENKALKAevdklREEVLD 54

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 1972262718 325 RRNTILERNKAAAVRYRKRKKEEHDDMMGRVQAMEAEKNQLLV-----RNEILY 373
Cdd:cd14687     1 KRKRFLERNRIAASKCRQRKKQWVQQLEEKVRKLESENKALKAevdklREEVLD 54

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.

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gi 1972262718 322 PDERRntilERNKAAAVRYRKRKKEEHDDMMGRVQAMEAEKNQLLVRNEIL 372
Cdd:cd14705     1 LEEKR----RRNTAASARFRAKKKQREQELEEKLKELEERIKELERRLDEL 47

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.

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gi 1972262718 331 ERNKAAAVRYRKRKKEEHDDMMGRVQAMEAEKNQLL-----VRNEILY 373
Cdd:cd14692     8 EQNKNAATRYRQKKREEKEELLSEEEELEDRNRELKdeveeLQREINY 55

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 1972262718 323 DERRNtilERNKAAAVRYRKRKKEEHDDMMGRVQAMEAEKNQLLVRNEIL 372
Cdd:cd14691     4 DLRRK---LKNRVAAQTARDRKKARMDELEERVRELEEENQKLRAENESL 50

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.

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gi 1972262718 325 RRNTIlernkaAAVRYRKRKKEEHDDMMGRVQAMEAEKNQLLVRNEIL 372
Cdd:cd12193     8 ARNTL------AARRSRARKLEEMEELEKRVEELEAENEELKTRAEVL 49

Basic leucine zipper (bZIP) domain of the oncogene Fos (Fos): a DNA-binding and dimerization domain; Fos proteins are members 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 four Fos proteins: c-Fos, FosB, Fos-related antigen 1 (Fra-1), and Fra-2. In addition, FosB also exists as smaller splice variants FosB2 and deltaFosB2. They all contain an N-terminal region and a bZIP domain. c-Fos and FosB also contain a C-terminal transactivation domain which is absent in Fra-1/2 and the smaller FosB variants. Fos proteins can only heterodimerize with Jun and other AP-1 proteins, but cannot homodimerize. Fos:Jun heterodimers are more stable and can bind DNA with more affinity that Jun:Jun homodimers. Fos proteins can enhance the trans-activating and transforming properties of Jun proteins. 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 1972262718 325 RRntilERNKAAAVRYRKRKKEEHDDMMGRVQAMEAEKNQLlvRNEI 371
Cdd:cd14721     5 RR----ERNKLAAAKCRQRRVDLTNTLQAETEQLEDEKSSL--QNEI 45

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 1972262718 323 DERRntilERNKAAAVRYRKRKKEEHDDMMGRVQAMEAEKNQL 365
Cdd:cd14809     2 ERRR----ERNREHARKTRLRKKAYLESLKEQVAALQAENQRL 40