BZIP transcription factor

Glover, J.N.M., Harrison, S.C. Crystal structure of the het-erodimeric bZIP transcription factor c-Fos-c-Jun bound to DNA. Nature 373 257-261, 1995. 

Our laboratory started to work on circadian rhythms by serendipity, while studying the liver-specific transcription of the serum albumin gene. We isolated a cDN A copy for a transcription factor that we dubbed DBP (for albumin promoter D-element Binding Protein). DBP, a basic leucine zipper (bZip) transcription factor, is the founding member of the PAR (proline-acidic amino acid rich)-domain bZip transcription factors, a small subfamily of bZip proteins consisting of DBP, TEF and HLF. It turned out that DBP protein and mRNA accumulation undergo circadian cycles with amplitudes in excess of one hundred-fold (Wuarin Schibler 1990). 

Jakoby, M. et al., bZIP transcription factors in Arahidopsis. Trends Plant Set, 1, 106, 2002. 

Wellmer, F., Schafer, E., and Harter, K., The DNA binding properties of the parsley bZIP transcription factor CPRF4a are regulated by light. J. Biol Chem., 276, 6274, 2001. 

Husberg C, Murphy P, Martin E, Kolsto AB. 2001. Two domains of the human bZIP transcription factor TCF11 are nec-... 

Chan JY, Kwong M, Lu R, Chang J, Wang B, et al. 1998. Targeted disruption of the ubiquitous CNC-bZIP transcription factor, Nrfl, results in anemia and embryonic lethality in mice. KMBOJ. 17 1779-87... 

Alarco, A.M. and Raymond, M. (1999) The bZip transcription factor Caplp is involved in multidrug resistance and oxidative stress response in Candida albicans. Journal of Bacteriology, 181, 700-708. 

Ehlert, A., Weltmeier, F., Wang, X., et al. (2006). Two-hybrid protein-protein interaction analysis in Arabidopsis protoplasts establishment of a heterodimeiization map of group C and group S bZIP transcription factors. Plant J., 46, 890-900. 

Several examples of proteins involved in signal transduction pathways are reported to be encoded by auxin-induced mRNAs. These include the 3-subunit of a heterotrimeric G-protein (arcA) [105,106], cyclin-dependent protein kinases (cdc2s) [107-111], and calmodulin (PCM-1 and arCAM) [112,113]. Putative transcription factors are also represented in the list of auxin-induced mRNAs. Auxin-responsive cDNA clones for a G-box binding bZIP transcription factor (SGBF-1) [114] and a homeobox transcription factor (Athb-8) have been reported [115]. Another auxin-responsive mRNA, dbp, was proposed to be a lysine-rich nuclear protein similar to HI histone, and the recombinant protein was shown to bind nonspecilically to DNA [116]. The amino acid sequence of dbp is, however, highly similar (i.e., 67% identity and 80% similarity) to a potato plasma membrane-associated protein called remorin [117]. The remorin protein binds to both simple and complex galacturonides as well as DNA, but is not a nuclear protein in potato... 

The homology of the ABRE to other elements makes it difficult to elucidate which protein(s) bind(s) to the ABRE in vivo. However, many proteins that bind to the ABRE in vitro have been cloned [22]. All of these proteins belong to the family of bZIP transcription factors so it is likely that an ABRE binding factor (ABF) will consist of bZlP proteins. In favour of this, the in vivo footprints on the functional ABREs of the rabl7 and rabl8 genes from maize are typical of plant bZIP proteins [12,14]. Unfortunately, the footprint is not sufficient to determine which bZIP protein(s) bind(s) to the element because different bZIP proteins give the same footprint [51]. 

In view of the participation of protein kinases and phosphatases in ABA signalling it is likely that constitutively bound transcription factors on ABA inducible genes could be regulated by phosphorylation or dephosphorylation. Activation of transcription by the mammalian bZIP transcription factor CREB is induced by phosphorylation of a serine... 

Figure 4.30 Proposed mechanisms for bZIP transcription factor function. Stable association of the bZIP dimer with DNA can occur via a monomer or dimer pathway. Binding of both monomer and dimer is diffusion limited. Analysis of the kinetics of both pathways suggests that the monomer pathway may have an overall kinetic advantage.

Berger, C., et al.. Diffusion-controlled DNA recognition by an unfolded, monomeric bZIP transcription factor. FEBS letters, 1998, 425, 14-18. 

Ogino H, Yasuda K (1998) Induction of lens differentiation by activation of a bZIP transcription factor, L-Maf. Science 280 115-118. 

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