Plant Mol Biol Rep (2011)29:525-532 D0110.1007/s11105-010-0256-3 Components of the Arabidopsis CBF Cold-Response Pathway Are Conserved in Non-heading Chinese Cabbage Fangling Jiang·Feng Wang·Zhen Wu.Ying Li· Gongjun Shi.Jingding Hu.Xilin Hou Published online:16 November 2010 C Springer-Verlag 2010 Abstract Many plants increase in freezing tolerance upon are similar to those of Arabidopsis.We conclude that exposure to low non-freezing temperatures,a phenomenon components of the CBF cold-response pathway are highly known as cold acclimation.Cold acclimation in Arabidopsis conserved in non-heading Chinese cabbage. involves rapid cold-induced expression of the inducer of C-repeat/dehydration-responsive element-binding factor Keywords Non-heading Chinese cabbage (CBF)expression (ICE)transcriptional activators followed Cold-responsive genes.ICE.CBF.COR by expression of the CBF;subsequently,CBF-targeted genes that increase freezing tolerance.Here,we present Abbreviations evidence for a CBF cold-response pathway in non-heading ICE Inducer of CBF expression Chinese cabbage (Brassica campestris ssp.chinensis L. CBF CRT-binding factors Makino).We show that non-heading Chinese cabbage COR Cold-regulated genes encodes ICEl-like gene BrICEI that bracket an open reading frame of 1,491 bp encoding a protein with a potential bHLH domain,which accumulates rapidly in response to low temperature followed closely by expres- Introduction sion of the BrCBF gene,an ortholog of the Arabidopsis CBF3-like gene,and then BrCOR/4 gene,an ortholog of Cold stress adversely affects plant growth and development the Arabidopsis CBF-targeted COR15b gene.An align- and thus limits crop productivity.Diverse plant species ment of the later two genes from Arabidopsis,Brassica tolerate cold stress to a varying degree,which depends on napus revealed the presence of conserved CANNTG core reprogramming gene expression to modify their physiology, element and AP2 domain in BrCBF and a CCG core metabolism,and growth.Cold signal in plants is transmit- element in BrCOR/4.In addition,BrCBF and BrCOR/4 ted to activate C-repeat/drought-responsive element-binding showed increased expression induced by low temperature factor (CBF)-dependent and CBF-independent transcrip- as well as salt and drought,but not by ABA stress which tional pathway,of which CBF-dependent pathway activates CBF regulon.CBF transcription factor genes are induced by the constitutively expressed inducer of CBF expression (ICE)1 by binding to the CBF promoter.ICE1-CBF cold- E.Jiang·E.Wang·Z.Wu.Y.Li·G.Shi·J.Hu·XHou(☒ response pathway is conserved in diverse plant species State Key Laboratory of Crop Genetics and Germplasm Enhancement, (Fowler et al.1996;Goulas et al.2003;Lee et al.2005; Nanjing 210095,China Chinnusamy et al.2007;Meng et al.2008;Wang et al. e-mail:hxl@njau.edu.cn 2009;Chinnusamy et al.2010).In this pathway,ICE's core sequence bHLH can recognize DNA with the consensus E.Jiang'E.Wang'Z.WuY.Li·G.Shi·J.Hu·XHou Key Laboratory of Southern Vegetable Crop Genetic sequence CANNTG (Chinnusamy et al.2003;Meshi and Improvement,Ministry of Agriculture, Iwabuchi 1995)involving in the CBF or DNA replication- Nanjing 210095,China related element-binding(DREB)proteins,while CBF or ②SpringerComponents of the Arabidopsis CBF Cold-Response Pathway Are Conserved in Non-heading Chinese Cabbage Fangling Jiang & Feng Wang & Zhen Wu & Ying Li & Gongjun Shi & Jingding Hu & Xilin Hou Published online: 16 November 2010 # Springer-Verlag 2010 Abstract Many plants increase in freezing tolerance upon exposure to low non-freezing temperatures, a phenomenon known as cold acclimation. Cold acclimation in Arabidopsis involves rapid cold-induced expression of the inducer of C-repeat/dehydration-responsive element-binding factor (CBF) expression (ICE) transcriptional activators followed by expression of the CBF; subsequently, CBF-targeted genes that increase freezing tolerance. Here, we present evidence for a CBF cold-response pathway in non-heading Chinese cabbage (Brassica campestris ssp. chinensis L. Makino). We show that non-heading Chinese cabbage encodes ICE1-like gene BrICE1 that bracket an open reading frame of 1,491 bp encoding a protein with a potential bHLH domain, which accumulates rapidly in response to low temperature followed closely by expres￾sion of the BrCBF gene, an ortholog of the Arabidopsis CBF3-like gene, and then BrCOR14 gene, an ortholog of the Arabidopsis CBF-targeted COR15b gene. An align￾ment of the later two genes from Arabidopsis, Brassica napus revealed the presence of conserved CANNTG core element and AP2 domain in BrCBF and a CCG core element in BrCOR14. In addition, BrCBF and BrCOR14 showed increased expression induced by low temperature as well as salt and drought, but not by ABA stress which are similar to those of Arabidopsis. We conclude that components of the CBF cold-response pathway are highly conserved in non-heading Chinese cabbage. Keywords Non-heading Chinese cabbage . Cold-responsive genes. ICE . CBF. COR Abbreviations ICE Inducer of CBF expression CBF CRT-binding factors COR Cold-regulated genes Introduction Cold stress adversely affects plant growth and development and thus limits crop productivity. Diverse plant species tolerate cold stress to a varying degree, which depends on reprogramming gene expression to modify their physiology, metabolism, and growth. Cold signal in plants is transmit￾ted to activate C-repeat/drought-responsive element-binding factor (CBF)-dependent and CBF-independent transcrip￾tional pathway, of which CBF-dependent pathway activates CBF regulon. CBF transcription factor genes are induced by the constitutively expressed inducer of CBF expression (ICE)1 by binding to the CBF promoter. ICE1-CBF cold￾response pathway is conserved in diverse plant species (Fowler et al. 1996; Goulas et al. 2003; Lee et al. 2005; Chinnusamy et al. 2007; Meng et al. 2008; Wang et al. 2009; Chinnusamy et al. 2010). In this pathway, ICE’s core sequence bHLH can recognize DNA with the consensus sequence CANNTG (Chinnusamy et al. 2003; Meshi and Iwabuchi 1995) involving in the CBF or DNA replication￾related element-binding (DREB) proteins, while CBF or F. Jiang : F. Wang : Z. Wu : Y. Li : G. Shi : J. Hu : X. Hou (*) State Key Laboratory of Crop Genetics and Germplasm Enhancement, Nanjing 210095, China e-mail: hxl@njau.edu.cn F. Jiang : F. Wang : Z. Wu : Y. Li : G. Shi : J. Hu : X. Hou Key Laboratory of Southern Vegetable Crop Genetic Improvement, Ministry of Agriculture, Nanjing 210095, China Plant Mol Biol Rep (2011) 29:525–532 DOI 10.1007/s11105-010-0256-3