Basic region leucine zipper;

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                  ....*....|....*....|....*....|....*....|....*....|
gi 167880409  259 EKTEKHERWKAAAKRYRTRLKQNQDMIAQRNAALEEENARLKAEVVRLRN 308
Cdd:pfam07716   1 EYRDRRRKNNEAAKRSREKKKQKEEELEERVKELERENAQLRQKVEQLEK 50

Cell division protein FtsB [Cell cycle control, cell division, chromosome partitioning];

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                 ....*....|....*....|....*....|....*..
gi 167880409 274 YRTRLKQNQDMIAQR--NAALEEENARLKAEVVRLRN 308
Cdd:COG2919   28 LLAYRELRQEIAELEaeNAKLKARNAELEAEVADLKD 64

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.

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                 ....*....|....*....|....*....|....*....|....*....|....*.
gi 167880409 260 KTEKH-ERWK---AAAKRYRTRLKQNQDMIAQRNAALEEENARLKAEVVRLRNLLQ 311
Cdd:cd14695    1 KDDKYwERRRknnLAAKRSRDARRLKENQIAIRAAFLEKENAALRAEIAKLKKELE 56

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 167880409 265 ERWKAAAKRYRTRLKQNQDMIAQRNAALEEENARLKAEVVRLRNLLQ 311
Cdd:cd14687    7 ERNRIAASKCRQRKKQWVQQLEEKVRKLESENKALKAEVDKLREEVL 53

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.

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                 ....*....|....*....|....*....|....*....|....*....|.
gi 167880409 257 DKEKTEKHERWKAAAKRYRTRLKQNQDMIAQRNAALEEENARLKAEVVRLR 307
Cdd:cd14694    2 DDKYWEKRRKNNEAAKRSREKRRLNDLVLENRILELTEENAVLRAELAALK 52

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 167880409 259 EKTE-KHERWKAAAKRYRTRLKQNQDMIAQRNAALEEENARLKAEVVRLRN 308
Cdd:cd14692    1 EKKErKREQNKNAATRYRQKKREEKEELLSEEEELEDRNRELKDEVEELQR 51

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
                 ....*....|....*....|....*....|....*...
gi 167880409 270 AAKRYRTRLKQNQDMIAQRNAALEEENARLKAEVVRLR 307
Cdd:cd14691   14 AAQTARDRKKARMDELEERVRELEEENQKLRAENESLR 51