Transcription activator that regulates freezing tolerance by affecting expression of CBF genes. Expressed in imbibed seeds, hypocotyls, cotyledons, roots, seedlings, siliques and flowers. Fades out in old roots and leaves. Induced by salicylic acid (SA), jasmonic acid (JA), salt (NaCl), ethylene and auxin (IAA) (PubMed:16463103). Down-regulated by cold treatment (PubMed:24415840). Increased tolerance to freezing stress and higher accumulation of CBF genes and downstream genes under cold treatment.