|Yuxin Jia,Shuhua Yang et al.The cbfs triple mutants reveal the essential functions of CBFs in cold acclimation and allow the deﬁnition of CBF regulons in Arabidopsis.New Phytologist.DOI:10.1111/nph.14088|
The cbfs triple mutants reveal the essential functions of CBFs in cold acclimation and allow the deﬁnition of CBF regulons in Arabidopsis
Yuxin Jia, Yanglin Ding, Yiting Shi, Xiaoyan Zhang, Zhizhong Gong and Shuhua Yang
In Arabidopsis, the C-repeat binding factors (CBFs) have been extensively studied as key transcription factors in the cold stress response. However, their exact functions in the cold response remains unclear due to the lack of a null cbf triple mutant. In this study, we used CRISPR/Cas9 technology to mutate CBF1 or CBF1/CBF2 in a cbf3 T-DNA insertion mutant to generate cbf1,3 double and cbf1 cbf2 cbf3 (cbfs) triple mutants. Theresponseofthecbfstriplemutantstochillingstressisimpaired.Furthermore,nosigniﬁcant difference in freezing tolerance was observed between the wild-type and the cbf1,3 and cbfs mutants without cold acclimation. However, the cbfs mutants were extremely sensitive to freezing stress after cold acclimation, and freezing sensitivity ranking was cbfs >cbf1,3>cbf3. RNA-Seq analysis showed that 134 genes were CBF regulated, of which 112 were regulated positively and 22 negatively by CBFs. Our study reveals the essential functions of CBFs in chilling stress response and cold acclimation, as well as deﬁnes a set of genes as CBF regulon. It also provides materials for the genetic dissection of components in CBF-dependent cold signaling.