作物学报2018，Vol.44Issue(3)：343-356,14.DOI:10.3724/SP.J.1006.2018.00343
玉米油菜素甾醇生物合成关键酶基因ZmCYP90B1的克隆及其对逆境胁迫的响应
Cloning of the Key Gene ZmCYP90B1 in Brassinosteroids Biosynthesis from Zea mays and Its Response to Adversity Stresses
摘要
Abstract
Brassinosteroids (BRs) as an important phytohormone,play essential roles in plant growth,development and responses to adversity stresses.The key enzyme encoded by CYP90B1 is involved in the BRs biosynthesis.However,the characteristic of CYP90B1 gene response to stress has not been reported in maize.In this study,we cloned ZmCYP90B1 gene from Zea mays,GenBank accession number KY242373,via RT-PCR in combination of RACE technique.The full-length sequence of this gene is 2058 bp and the the complete open reading frame is 1518 bp,encoding 506 amino acid peptides.The predicted protein has the molecular weight of 57.66 kD and isoelectric point of 9.54,containing one transmembrane domain and one conserved domain of p450.Multiple sequences alignment analysis indicated the predicted protein shared high similarities with CYP90B1 from other plant species.The phylogenetic tree revealed a notable difference in the evolution of CYP90B1 between dicotyledons and monocotyledons.The qRT-PCR result showed that the expression of ZmCYP90B1 was induced by drought,high salt,low temperature,ABA,Spodoptera exigua attack,and methyl jasmonate (MeJA),suggesting that ZmCYP90B1 was involved in various abiotic stresses,insect resistance and response to MeJA.Overexpressing ZmCYP90B1 in tobacco seedlings could enhance drought resistance with less water loss rate and higher SPAD value in the transgenic lines.In addition,the activities of SOD,CAT,and POD and the content of proline increased significantly in all transgenic tobacco lines than in the wild type;both MDA and ABA contents were obviously lower in the transgenic lines than in the wild type.Through expression analysis of the down-stream stress-responsive genes,we demonstrated that drought tolerance enhancement by overexpressing ZmCYP90B1 might be involved in ABA-independent pathway and related to transcriptional regulation of antioxidant-related genes.关键词
油菜素甾醇/ZmCYP90B1基因/实时荧光定量PCR/逆境胁迫Key words
brassionsteroids/ZmCYP90B1 gene/real-time quantitative PCR/adversity stresses引用本文复制引用
段方猛,罗秋兰,鲁雪莉,齐娜伟,刘宪舜,宋雯雯..玉米油菜素甾醇生物合成关键酶基因ZmCYP90B1的克隆及其对逆境胁迫的响应[J].作物学报,2018,44(3):343-356,14.基金项目
本研究由青岛市应用基础研究计划项目(16-5-1-54-jch),山东省自然科学基金项目(ZR2013CQ028),深圳市科技计划项目(JCYJ20150324141711583)和青岛农业大学博士基金项目(663/1111316)资助.This study was supported by Qingdao Applied Basic Research Project (16-5-1-54-jch),Shandong Province Natural Science Foundation (ZR2013CQ028),Shenzhen Grant Plan for Science& Technology (JCYJ20150324141711583),and the Doctor Program of Higher Education (663/1111316). （16-5-1-54-jch）
