小麦光温敏雄性不育系BS237ω-黑麦碱基因克隆及序列分析

Cloning and Sequence Analysis ofω-Secalin Gene in Wheat Photothermal-Sensitive Male Sterile Line BS237

为研究小麦光温敏雄性不育系BS237中ω-黑麦碱基因编码区特征,利用同源克隆的方法克隆ω-黑麦碱基因的编码区序列,共得到8条具有完整开放阅读框的基因序列(OK999982~OK999985,OK999987~OK999990),基因编码区长度为1002~1074 bp,可编码333~357个氨基酸残基,全部编码RQL型ω-黑麦碱蛋白。NCBI BLAST分析表明克隆序列与已知序列的相似度在91%~100%之间,推断其为ω-黑麦碱基因家族。进化分析表明8个克隆的基因与普通小麦(Triticum aestivum L.)和黑麦(Secale cereale L.)的ω-黑麦碱基因序列具有较高的同源性,说明ω-黑麦碱基因具有一定的基因组特异性。乳糜泻(CD)免疫肽识别分析表明,8个基因中均分布有5种T细胞免疫肽——Gli-ωt(PQQPFPQQ)、DQ2.5-glia-γ5(QQPFPQQPQ)、QQPY、SPQQ和PQQP,且肽段Gli-ωt(PQQPFPQQ)和PQQP存在多个拷贝。本研究结果可为1BL/1RS类型杂交小麦加工品质的分子改良及乳糜泻疾病的预防提供参考。

In order to study the characteristics ofω-secalin gene coding region in wheat photothermal-sensitive male sterile line BS237,the sequence ofω-secalin gene coding region was cloned by homologous clo-ning method.The results showed that eight different gene sequences(OK999982~OK999985,OK999987~OK999990)were cloned,which had complete open reading frames,and the length variation of gene coding region ranged from 1002 bp to 1074 bp,encoding 333~357 amino acid residues and all encoding RQLω-secalin protein.NCBI BLAST analysis showed that the similarity between the cloned sequence and known se-quence ranged from 91%to 100%,suggesting that the cloned sequences beω-secalin gene family.Cluster a-nalysis showed that the eight cloned genes had high homology withω-secalin gene sequences of Triticum aesti-vum L.and Secale cereale L.,suggesting thatω-secalin genes have certain genomic specificity.The celiac disease(CD)toxicity analysis showed that five immunopeptide were distributed in all the eight genes,including Gli-ωt(PQQPFPQQ),DQ2.5-glia-γ5(QQPFPQQPQ),QQPY,SPQQ and PQQP.Multiple copies of Gli-ωt(PQQPFPQQ)and PQQP existed in all the eight genes.The results of this study could provide references for molecular improvement of processing quality in 1BL/1RS type hybrid wheat and prevention of celiac disease.