The role of TaCHP in salt stress responsive pathways.

In our previous study, we found wheat TaCHP confers salt tolerance through regulating salt responsive signaling pathways. TaCHP possesses three divergent C1 domains that can specifically bind to phospholipid signaling molecule diacylglycerol (DAG) in animal cells, and most of proteins with this domain have kinase activity. Here, we found that TaCHP localizes both at cytoplasmatic membrane and in nuclei; it has no kinase activity but transcriptional activation activity, and the latter owes to C-terminal two C1 domains. TaCHP transcription was reduced by H2O2 application, but its ectopic expression in Arabidopsis improved both ROS production and scavenging capacity, and enhanced tolerance to H2O2 application. We suggest that TaCHP serve as both a transcription factor and a putative DAG binding protein to confer salt tolerance in part through improving ROS scavenging capacity; which is a component of the cross-talk machinery in the phospholipids-ROS-salt responsive signaling pathways.