Arabidopsis ABI5 subfamily members have distinct DNA-binding and transcriptional activities.
A small family of novel basic leucine zipper proteins that includes abscisic acid (ABA)-INSENSITIVE 5 (ABI5) binds to the promoter region of the lea class gene Dc3. The factors, referred to as AtDPBFs (Arabidopsis Dc3 promoter-binding factors), were isolated from an immature seed cDNA library. AtDPBFs bind to the embryo specification and ABA-responsive elements in the Dc3 promoter and are unique in that they can interact with cis-elements that do not contain the ACGT core sequence required for the binding of most other plant basic leucine zipper proteins. Analysis of full-length cDNAs showed that at least five different Dc3 promoter-binding factors are present in Arabidopsis seeds; one of these, AtDPBF-1, is identical to ABI5. As expected, AtDPBF-1/ABI5 mRNA is inducible by exogenous ABA in seedlings. Despite the near identity in their basic domains, AtDPBFs are distinct in their DNA-binding, dimerization, and transcriptional activity.
Kim
Soo Young
SY
Department of Biology, Texas A&M University, College Station, TX 77843-3258, USA.
Ma
Jianzhong
J
Perret
Philippe
P
Li
Zhongsen
Z
Thomas
Terry L
TL
D000040:Abscisic Acid / Q000494:pharmacology; D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000235:genetics* / Q000378:metabolism; D029681:Arabidopsis Proteins / Q000235:genetics* / Q000378:metabolism; D050976:Basic-Leucine Zipper Transcription Factors; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D018506:Gene Expression Regulation, Plant / Q000235:genetics; D016350:Leucine Zippers / Q000235:genetics; D008969:Molecular Sequence Data; D005810:Multigene Family / Q000235:genetics*; D010802:Phylogeny; D020033:Protein Isoforms / Q000235:genetics / Q000378:metabolism; D012639:Seeds / Q000235:genetics / Q000378:metabolism; D017386:Sequence Homology, Amino Acid; D014157:Transcription Factors / Q000235:genetics* / Q000378:metabolism*; D015533:Transcriptional Activation; D020798:Two-Hybrid System Techniques; D015003:Yeasts / Q000235:genetics
C409743:ABI5 protein, Arabidopsis; D029681:Arabidopsis Proteins; D050976:Basic-Leucine Zipper Transcription Factors; D004268:DNA-Binding Proteins; C107885:DPBF-2 protein, Arabidopsis; D020033:Protein Isoforms; D014157:Transcription Factors; D000040:Abscisic Acid