ABI5
Developmental stage
Expressed in embryo during the latest stages of seed maturation.
Function
Participates in ABA-regulated gene expression during seed development and subsequent vegetative stage by acting as the major mediator of ABA repression of growth. Binds to the embryo specification element and the ABA-responsive element (ABRE) of the Dc3 gene promoter and to the ABRE of the Em1 and Em6 genes promoters. Can also trans-activate its own promoter, suggesting that it is autoregulated. Plays a role in sugar-mediated senescence.
Post-translational modifications
Phosphorylated by SRK2D and SRK2I in vitro.
Ubiquitinated. AFP1, KEG and RPN10 mediate its proteasome-dependent degradation. Its stability or degradation plays a central role in abscisic acid response. Sumoylated at Lys-391 by SIZ1. Sumoylation protects ABI5 from proteasome degradation, attenuating ABA signaling and sensitivity to ABA.
Sequence Similarities
Belongs to the bZIP family. ABI5 subfamily.
Tissue Specificity
Predominantly expressed in seeds.
Cellular localization
- Nucleus
Alternative names
BZIP39, DPBF1, GIA1, NEM1, At2g36270, F2H17.12, ABI5, Protein ABSCISIC ACID-INSENSITIVE 5, Dc3 promoter-binding factor 1, Protein GROWTH-INSENSITIVITY TO ABA 1, bZIP transcription factor 39, AtDPBF1, AtbZIP39