ICE1, a Transcription Factor Involved in Cold Signaling and Tolerance

Abstract

Cold stress is a major factor that limits the development, productivity, and geographical distribution of plants. To adapt to a low temperature, plants have developed mechanisms to tolerate cold stress. Cold signals in plants are transmitted to inducer of CBF expression1 (ICE1), a basic helix-loop-helix transcription factor, which activates the C-repeat-binding factor/dehydration-responsive element-binding protein regulon. ICE1 is posttranslationally regulated by ubiquitylation, mediated by the high expression of osmotically responsive gene1 (HOS1) ubiquitin E3 ligase, and sumoylation, mediated by the SIZ1 small ubiquitin-related modifier E3 ligase. ICE1 is functionally conserved in different plant species and its overexpression in tomato and cucumber increases chilling tolerance. The introduction of wheat ICE1 enhances cold tolerance in Arabidopsis. In this chapter, the recent progress in studying ICE1-dependent cold signaling in Arabidopsis and its functional conservation in crops will be summarized.