Arabidopsis calcium-dependent protein kinase AtCPK32 interacts with ABF4, a transcriptional regulator of abscisic acid-responsive gene expression, and modulates its activity.

The phytohormone abscisic acid (ABA) regulates stress-responsive gene expression during vegetative growth. The ABA regulation of many genes is mediated by a subfamily of basic leucine zipper class transcription factors referred to as ABFs (i.e.

Arabidopsis basic leucine zipper proteins that mediate stress-responsive abscisic acid signaling.

The phytohormone abscisic acid (ABA) plays an essential role in adaptive stress responses. The hormone regulates, among others, the expression of numerous stress-responsive genes. From various promoter analyses, ABA-responsive elements (ABREs) have been determined and a number of ABRE binding factors have been isolated, although their in vivo roles are not known.