Molecular characterization of a bHLH transcription factor involved in Arabidopsis abscisic acid-mediated response.
The suppression subtractive hybridization (SSH) method was used to isolate abscisic acid (ABA)-regulated genes in Arabidopsis. We report that the AtAIG1 gene is up-regulated by ABA and the AtAIG1 encodes a basic/helix-loop-helix (bHLH)-type transcription factor in Arabidopsis. The AtAIG1 was targeted into nucleus and bound to the E-box-DNA sequence, which is found in the promoter regions of many ABA-responsive genes. Functional analyses with the ataig1 knockout mutants revealed that the mutant plants show enhanced sensitivity to ABA. In addition, the ataig1 plants showed reduced expression of ABA-responsive genes, such as RD29A and RD22. Thus, these functional analyses suggest that the AtAIG1 protein plays an important role in ABA-mediated signal transduction pathway.
Kim
Jiyoung
J
Kiyong Biotechnology, Saha-Gu, Busan 604-083, South Korea.
Kim
Ho-Young
HY
D000040:Abscisic Acid / Q000494:pharmacology*; D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000187:drug effects* / Q000235:genetics / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D051792:Basic Helix-Loop-Helix Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D008969:Molecular Sequence Data; D011485:Protein Binding
D000040:Abscisic Acid; D029681:Arabidopsis Proteins; D051792:Basic Helix-Loop-Helix Proteins; C511959:AIG1 protein, Arabidopsis