【目的】阐明荞麦Fagopyrum中3个种子蛋白基因序列的特征及其在种子发育过程中的作用,为探讨荞麦种子发育过程分子机制提供理论依据。【方法】利用本地Perl程序、BLASTP、MEGA6、PLANTCARE等,分析了荞麦3个种子蛋白基因(13S球蛋白基因、11S球蛋白基因和谷蛋白基因)序列及其编码蛋白质的进化关系,预测启动子区域的顺式作用元件。通过荧光定量PCR技术分析3个基因在甜荞F.esculentum、苦荞F.tataricum和金荞F.cymosum种子发育过程中的表达情况。【结果】13S球蛋白基因含有4个外显子和3个内含子,蛋白序列长515 aa,与苦荞中的一个13S球蛋白(Gene Bank登录号:ABI32184.1)仅有6个氨基酸不同,推测二者为同一个基因,在苦荞灌浆中期表达量最高;11S球蛋白基因含有8个外显子和7个内含子,蛋白序列长914 aa,与欧洲慈姑中的一个11S球蛋白(Gene Bank登录号:ABB77213.1)亲缘关系最近,在苦荞灌浆中期表达量最高;谷蛋白基因含有3个外显子和2个内含子,蛋白序列长355 aa,与甜菜中的一个B5型谷蛋白(Gene Bank登录号:XP010683769.1)亲缘关系最近,在甜荞灌浆中期表达量最高。3个基因的启动子区域均含有大量响应逆境和激素的顺式作用元件,以及在胚乳中表达所需的顺式作用元件。【结论】本研究获得了1个13S球蛋白基因序列、1个11S球蛋白基因序列和1个谷蛋白基因序列,这3个基因可能在胚乳中优势表达,并且参与到逆境胁迫和激素响应的过程中;灌浆中期是种子蛋白积累的关键时期,3个基因均在这一时期大量表达,这为后续进一步研究基因功能奠定了基础。
【Objective 】 To clarify the sequence features and functions of three seed protein genes of buckwheat,providing a theoretical foundation for studying the molecular mechanism during seed development.【Method】Using local Perl script,BLASTP,MEGA6 and PLANTCARE,the sequences and evolutionary relationships of three buckwheat seed protein genes,namely 13 S globulin gene,11 S globulin gene and glutelin gene,were analyzed.The cis-regulatory elements in the promoter region were predicted.Using the qRT-PCR technology,the expression patterns of three genes were analyzed during seed development of Fagopyrum esculentum,F.tataricum and F.cymosum.【Result】The 13 S globulin gene included four exons and three introns.The protein length was 515 aa.This 13 S globulin only had six different amino acid sites compared with another 13 S globulin in F.tataricum(ABI32184.1),thus they might be the same gene.The expression level was the highest in the middle filling stage of F.tataricum.The 11 S globulin gene included eight exons and seven introns.The protein length was 914 aa,and it was most closly related to a 11 S globulin in Sagittaria sagittifolia(CAA70334.1).The expression level was the highest in the middle filling stage of F.tataricum.The glutelin gene included three exons and two introns.The protein length was 355 aa,and it was most closly related to a B5-type glutelin in Beta vulgaris(XP010683769.1).The expression level was the highest in the middle filling stage of F.esculentum.The promoter regions of three genes contained various cis-acting elements which responded to stresses and phytohormones, as well as cis-acting elements required for endosperm expression.【Conclusion】The sequences of 13 S globulin,11 S globulin and glutelin genes are obtained.These genes might be preferentially expressed in endosperm, and involved in stress and hormone responsive processes.The middle filling stage is the key stage for seed protein accumulation,and three genes are massively expressed at this stage,which provides a so