Transcription repressor that binds to 5'-TATCCA-3' elements in gene promoters. Contributes to the sugar-repressed transcription of promoters containing SRS or 5'-TATCCA-3' elements. Transcription repressor involved in a cold stress response pathway that confers cold tolerance. Suppresses the DREB1-dependent signaling pathway under prolonged cold stress. DREB1 responds quickly and transiently while MYBS3 responds slowly to cold stress. They may act sequentially and complementarily for adaptation to short- and long-term cold stress (PubMed:20130099). Expressed in all tissues, with the highest level in senescent leaves. Repressed by sucrose and gibberellic acid (GA) (PubMed:12172034). Induced by cold stress in roots and shoots. Induced by salt stress in shoots. Down-regulated by abscisic aci (ABA) in shoots (PubMed:20130099). Plants over-expressing MYBS3 show increased tolerance to cold stress.