摘要
【目的】研究TaGSTF6基因多态性与抗旱性的关系。植物谷胱甘肽-S-转移酶(GSTs)是一类重要的受逆境胁迫诱导表达的酶类,能减少干旱等逆境胁迫导致的体内活性的氧积累,在植物的抗旱反应中发挥重要作用。【方法】以86份抗旱性不同的普通小麦品种和7份粗山羊草为材料,检测TaGSTF6基因的核苷酸序列长度及碱基组成多态性,并预测氨基酸序列多态性。【结果】Northern分析结果表明,小麦幼苗中TaGSTF6基因受水分胁迫诱导表达。序列多态性分析发现在长达113.6 kb的核苷酸序列中有47个单核苷酸变异位点,其中23个SNP,24个InDel,二者的频率分别为1SNP/4 940bp和1InDel/4 734bp,粗山羊草中SNP和InDel出现的频率明显高于普通小麦;仅在11份材料中预测到氨基酸序列多态性。根据核苷酸序列变异可能导致的氨基酸变异把基因编码区的变异分为两类:核苷酸转换或颠换导致的单个氨基酸变异;碱基缺失导致的移码突变或翻译提前终止,其中大多数变异属于移码突变。【结论】尽管小麦基因组庞大,重复序列多,但在功能基因TaGSTF6中SNP的分布频率非常低;虽然TaGSTF6受水分胁迫诱导表达,但其结构多态性分析未能揭示其多态性与小麦抗旱性之间的直接关系。
[Objective] Glutathione S-transferases （GSTs） are abundant proteins in plants and play very important roles in reducing the toxicity of reactive oxygen species （ROS） induced by biotic and abiotic stress, They also enhance plants＇ drought tolerance, [Method ] Eighty-six common wheat accessions and seven Aegilops. tauschii, the donor species of common wheat D genome, were used to probe TaGSTF6 gene polymorphisms and the relationship between the polymorphisms and drought tolerance, [Result] Forty-seven nucleotide mutations were detected, including 23 SNP （single nucleotide polymorphism） and 24 InDel （insertion-deletion）, from 113,6 kb nucleotide acid sequence, The frequencies of SNP and InDel were 1/4 940 bp and 1/4 734 bp, respectively, The frequencies of SNP and lnDel in Ae. tauschii are much higher than that in commbn wheat, Based on the TaGSTF6 sequence polymorphisms, putative amino acid polymorphisms were only found in 11 common wheat accessions, Northern blotting indicated that TaGSTF6 was regulated by water-stress in wheat seedlings; however, the significant correlation between the drought tolerance and the polymorphisms of TaGSTF6 at both levels nucleotide acid and amino acid were not identified, This further suggested the complexity of drought tolerance in wheat. [ Conclusion ] The results suggest though the genome of wheat is gigantic and abundant in repeat sequences, the frequency of SNP is very low in functional gene TaGSTF6. Although the expression of TaGSTF6 is induced by water stress, no direct relationship between polymorphism and drought tolerance was identified.
出处
《中国农业科学》
CAS
CSCD
北大核心
2007年第2期225-233,共9页
Scientia Agricultura Sinica
基金
国家973重点基础项目(2004CB117205)
