一个与小麦雄性不育育性转换相关的MADS-box转录因子基因

作物学报ACTA AGRONOMICA SINICA 2008， 34（4）： 598-604

http：///zwxb/ISSN 0496-3490； CODEN TSHPA9E-mail： xbzw@

基金项目：教育部重点科研项目（105166）； 陕西省留学回国人员科研经费； 教育部春晖计划启动项目（Z2005-2-7104）

作者简介：璘周琳（1982-）， 女， 硕士研究生， 主要从事作物分子遗传育种研究。E-mail： linlinzhou1219@

*通讯作者（Corresponding author）: 胡银岗。E-mail： huyingang@； huyingang@

Received（收稿日期）: 2007-09-29； Accepted（接受日期): 2007-10-30. DOI： 10.3724/SP.J.1006.2008.00598

一个与小麦雄性不育育性转换相关的MADS-box 转录因子基因

璘周琳1 宋国琦1 李红燕1 胡银岗1，2，3，* 何蓓如1

（1西北农林科技大学农学院， 陕西杨凌 712100； 2国家小麦改良中心杨凌分中心， 陕西杨凌712100； 3陕西省农业分子生物学重点实验

室， 陕西杨凌 712100）

摘 要：为了揭示YS 型小麦温敏雄性不育育性转换的基础， 构建了该类型不育系A3017的不育和可育幼穗正、反杂交的两个SSH-cDNA 文库。经文库比较， 在不育文库中筛选出一个与MADS-box 基因同源的EST 序列（GenBank 登录号： 36925702）。以该EST 序列的同源性比对和拼接结果为依据， 设计引物对该基因在可育和不育幼穗中的表达进行了RT-PCR 分析， 结果表明， 该基因在不育幼穗中表达量较高， 可育幼穗中表达量很低。对不育幼穗中扩增出的cDNA 片段进行克隆测序， 获得了666 bp 的cDNA 序列。序列分析表明， 该片段编码160个氨基酸， 具有MADS-box 转录因子的典型结构域K-box， 被定名为TaMS-MADSbox ， 与一个小麦MADS box 转录因子基因WAG 的氨基酸序列的相似性为94%。进一步以3种不同类型的小麦雄性不育系和保持系的幼穗cDNA 为材料， 利用半定量RT-PCR 对该基因的表达模式分析发现也存在类似差异， 该基因在不育系幼穗中表达量较高， 而保持系幼穗中表达量较低。以上分析表明， 该MADS-box 转录因子基因的表达与小麦雄性不育系的育性转化相关， 表达量高时表现雄性不育， 表达量低时表现雄性可育。

关键词：普通小麦； 温敏雄性不育； 育性转换； MADS-box 转录因子； 表达分析

A MADS-Box Transcription Factor Related to Fertility Conversion in Male Sterile Wheat Lines

ZHOU Lin-Lin 1， SONG Guo-Qi 1， LI Hong-Yan 1， HU Yin-Gang 1，2，3，*， and HE Bei-Ru 1

（1 College of Agronomy， Northwest A&F University， Yangling 712100， Shaanxi； 2 Yangling Branch of China National Wheat Improvement Centre， Yangling 712100， Shaanxi； 3 Key Laboratory of Molecular Biology for Agriculture of Shaanxi Province， Yangling 712100， Shaanxi， China） Abstract ： Male sterility is one of the major characteristics to be used in heterosis utilization of crops， in which thermo-sensitive or photo-sensitive male sterility is very important for two-line hybridization due to the conversion of their male fertility under special weather conditions. YS type thermo-sensitive male sterile wheat （Triticum astivum L .） lines are applicable for heterosis use in the major wheat production areas of northern China.To investigate the molecular basis of male fertility conversion of YS type thermo-sensitive male sterile wheat lines， we constructed the sterile and fertile suppression subtractive hybridization （SSH） cDNA libraries respectively， using the cDNA of the male sterile or fertile young spikes from the same individual of one YS type thermo-sensitive male sterile wheat line A3017 under controlled male sterile or fertile conditions. Comparing the EST sequences between the two cDNA libraries， an EST （GenBank accession number： 36925702） highly similar to MADS box transcription fac-tor gene was selected from the sterile SSH-cDNA library and used as the probe to search the dbEST. A pair of primers was de-signed based on the aligned sequence of highly homological EST sequences， and used to detect the expression difference of this gene between male sterile and fertile spikes via Reverse Transcriptase PCR （RT-PCR）. The results showed that the expression of this gene in male sterile spikes was much higher than that in fertile spikes. Then the RT-PCR fragment amplified from the male sterile spikes was cloned and sequenced， a cDNA sequence with 666 bp and encoding 160 amino acids was obtained. The cDNA fragment contained the typical K-box domain of MADS-box， and designated as TaMS-MADSbox . The deduced amino acids were 94% similar to WAG （BAC22939）， an MADS box transcription factor of wheat. The expression profiles of this MADS-box tran-scription factor gene in the male-sterile lines and their maintainers of three types of male sterile wheat lines were further analyzed