The clustered genes C-repeat (CRT) binding factor (CBF)1/dehydration-responsive element binding protein (DREB)1B, CBF2/DREB1C, and CBF3/DREB1A play a central role in cold acclimation and facilitate plant resistance to freezing in Arabidopsis thaliana. Rice (Oryza sativa L.) is very sensitive to low temperatures; enhancing the cold stress tolerance of rice is a key challenge to increasing its yield. In this study, we demonstrate chilling acclimation, a phenomenon similar to Arabidopsis cold acclimation, in rice. To determine whether rice CBF/DREB1 genes participate in this cold-responsive pathway, all putative homologs of Arabidopsis DREB1 genes were filtered from the complete rice genome through a BLASTP search, followed by phylogenetic, colinearity and expression analysis. We thereby identified 10 rice genes as putative DREB1 homologs: nine of these were located in rice genomic regions with some colinearity to the Arabidopsis CBF1–CBF4 region. Expression profiling revealed that six of these genes (Os01g73770, Os02g45450, Os04g48350, Os06g03670, Os09g35010, and Os09g35030) were similarly expressed in response to chilling acclimation and cold stress and were co-expressed with genes involved in cold signalling, suggesting that these DREB1 homologs may be involved in the cold response in rice. The results presented here serve as a prelude towards understanding the function of rice homologs of DREB1 genes in cold-sensitive crops.
擬南芥中簇集基因CRT（C-repeat）結(jié)合因子（CBF）1/脫水應(yīng)答原件結(jié)合蛋白（DREB）1B，CBF2/DREB1C和CBF3/DREB1A在冷適應(yīng)以及促進(jìn)植物冷耐受性中發(fā)揮核心作用。水稻對(duì)低溫非常敏感，提高水稻對(duì)冷脅迫的耐受能力是增產(chǎn)的一個(gè)重要挑戰(zhàn)。本研究我們證明水稻具有與擬南芥類(lèi)似的冷適應(yīng)現(xiàn)象。為了分析水稻CBF/DREB1是否參與了冷應(yīng)答途徑，通過(guò)BLASTP對(duì)水稻基因組中擬南芥DREB1同源基因進(jìn)行篩選，并進(jìn)行系統(tǒng)發(fā)生、共線性以及表達(dá)分析。我們一共鑒定了10個(gè)水稻DREB1同源基因：其中9個(gè)在水稻基因組中的位置與擬南芥CBF1-CBF4位置具有共線性。表達(dá)譜揭示其中6個(gè)基因（Os01g73770, Os02g45450, Os04g48350, Os06g03670, Os09g35010, and Os09g35030）對(duì)冷適應(yīng)以及冷脅迫的應(yīng)答類(lèi)似，并且與參與冷信號(hào)的基因共表達(dá)，表明這些DREB1同源基因可能也參與了水稻的冷應(yīng)答。這些結(jié)果可以認(rèn)為是理解水稻DREB1同源基因在冷敏感作物中功能的一個(gè)前奏。