A conserved proline residue in the leucine zipper region of AtbZIP34 and AtbZIP61 in Arabidopsis thaliana interferes with the formation of homodimer.
Two putative Arabidopsis E group bZIP transcript factors, AtbZIP34 and AtbZIP61, are nuclear-localized and their transcriptional activation domain is in their N-terminal region. By searching GenBank, we found other eight plant homologues of AtbZIP34 and AtbZIP61. All of them have a proline residue in the third heptad of zipper region. Yeast two-hybrid assay and EMSA showed that AtbZIP34 and AtbZIP61 could not form homodimer while their mutant forms, AtbZIP34m and AtbZIP61m, which the proline residue was replaced by an alanine residue in the zipper region, could form homodimer and bind G-box element. These results suggest that the conserved proline residue interferes with the homodimer formation. However, both AtbZIP34 and AtbZIP61 could form heterodimers with members of I group and S group transcription factors in which some members involved in vascular development. So we speculate that AtbZIP34 and AtbZIP61 may participate in plant development via interacting with other group bZIP transcription factors.
Shen
Huaishun
H
College of Life Sciences, Beijing Normal University, Beijing 100875, PR China.
Cao
Kaiming
K
Wang
Xiping
X
D000595:Amino Acid Sequence; D029681:Arabidopsis Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D050976:Basic-Leucine Zipper Transcription Factors / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D001665:Binding Sites / Q000235:genetics; D002467:Cell Nucleus / Q000378:metabolism; D017124:Conserved Sequence; D003593:Cytoplasm / Q000378:metabolism; D019281:Dimerization; D024202:Electrophoretic Mobility Shift Assay; D049452:Green Fluorescent Proteins / Q000235:genetics / Q000378:metabolism; D016350:Leucine Zippers / Q000235:genetics; D008856:Microscopy, Fluorescence; D008969:Molecular Sequence Data; D019697:Onions / Q000166:cytology / Q000378:metabolism; D011392:Proline / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D011485:Protein Binding; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D015533:Transcriptional Activation; D020798:Two-Hybrid System Techniques; D015003:Yeasts / Q000235:genetics
D029681:Arabidopsis Proteins; D050976:Basic-Leucine Zipper Transcription Factors; D011993:Recombinant Fusion Proteins; D049452:Green Fluorescent Proteins; D011392:Proline