低温胁迫对甘蔗叶绿体蛋白质及其相关基因表达的影响  

Effects of Chilling Stress on Protein and Related Gene Expression in Chloroplasts of Sugarcane

作　　者：黄巧玲[1] 黄杏[1] 孙富[1] 孙波[1] 杨丽涛[1] 李杨瑞[1,2] 

机构地区：[1]广西大学农学院/亚热带农业生物资源保护与利用国家重点实验室,南宁530005 [2]中国农业科学院甘蔗研究中心/农业部广西甘蔗生物技术与遗传改良重点实验室/广西作物遗传改良生物技术重点实验室/广西甘蔗遗传改良重点实验室,南宁530007

出　　处：《中国农业科学》2012年第24期4978-4987,共10页Scientia Agricultura Sinica

基　　金：国家科技支撑计划项目(2007BAD30B00;2008BADB8B00);国家国际合作项目(2008DFA30600;2009DFA30820);广西自然科学基金创新团队项目(2011GXNSFF018002);广西农科院团队项目(桂农科2011YT01)

摘　　要：【目的】从蛋白质水平和mRNA水平揭示低温胁迫对甘蔗叶绿体的影响,为探讨甘蔗抗寒机制提供参考依据。【方法】以桂糖28号(GT28,抗寒性强)和新台糖22号(ROC22,抗寒性弱)为材料,对其进行9 d、15 d和24 d不同天数的低温胁迫,以及叶绿体蛋白质电泳分析,再通过实时荧光定量PCR技术分析相关基因受低温胁迫后的表达情况。【结果】电泳分析结果表明,低温胁迫后两个甘蔗品种的蛋白质条带都随着胁迫时间的延长减弱,且ROC22的降解幅度大于桂糖28号,其中分子量为39.92 kD、32.95 kD以及22.87 kD处的蛋白条带下降较为明显。质谱分析结果发现,它们分别是ATP合酶γ亚基、放氧蛋白1和光系统II 23 kD蛋白,分别由atpC、psbO和psbP基因编码。克隆出它们的基因片段长度分别为937、996和721 bp。其中psbO基因片段是个完整的开放阅读框(ORF),GenBank登录号为JQ898540。实时荧光定量PCR分析结果表明,psbO基因和psbP基因受低温的诱导,在胁迫15 d时达到最大;而atpC基因受低温抑制。【结论】低温胁迫促进了叶绿体蛋白质的降解,且ROC22的降解幅度大于GT28。低温抑制atpC基因的表达,但却诱导了psbO基因和psbP基因的表达。【Objective】 The present study was conducted to investigate the effects of chilling stress on chloroplasts at protein and mRNA levels to provide references for further investigation on molecular mechanism of chilling stress in sugarcane.【Method】Sugarcane varieties GT28 （strong cold resistant sugarcane variety） and ROC22 （weak cold resistant sugarcane variety） were employed as the plant materials, and treated for 9 d, 15 d and 24 d of chilling stress, respectively, and then the chloroplast protein was extracted and used for electrophoresis analysis, and expressions of the genes were analyzed using real-time PCR.【Result】The results of electrophoresis analysis showed that, for both sugarcane varieties, the relative content of chloroplast protein decreased with the chilling time extension. The protein bands of 39.92, 32.95 and 22.87 kD were down-regulated obviously. Mass spectrometry revealed that they were ATP synthase subunit gamma, oxygen-evolving enhancer protein 1 and chloroplast 23 kD polypeptide of photosystem II, and they were encoded by atpC, psbO and psbP genes, respectively. Their fragment length was 937, 996, and 721 bp, respectively. The obtained fragment of psbO gene was its complete open reading frame, which has been registered in the GenBank with the accession number JQ898540. Real-time PCR analysis showed that chilling stress suppressed the expression of atpC gene, but induced the expressions of psbO and psbP genes, which reached the maximum at the time point of 15 d. 【Conclusion】 Generally, chilling stress promoted protein degradation, and the protein declined more in ROC22 than that in GT28. Chilling stress suppressed the expression of atpC gene, but induced the expressions of psbO and psbP genes in chloroplasts of sugarcane.

关 键 词：低温胁迫 甘蔗 叶绿体 蛋白质组 差异表达 

分 类 号：S566.1[农业科学—作物学]