谷子蔗糖磷酸合成酶及互作蛋白的生物信息和基因表达分析  

Bioinformatics and Gene Expression Analysis on Sucrose Phosphate Synthase and Its Interacting Proteins in Millet

作　　者：范会 刘红云[1] 程金金[1] 刘征[1] 

机构地区：[1]河北大学生命科学学院,河北071002

出　　处：《基因组学与应用生物学》2017年第12期5223-5231,共9页Genomics and Applied Biology

基　　金：河北省自然科学基金(No.C2015201176);教育部留学回国人员科研启动基金(No.2011-1139)资助

摘　　要：蔗糖在植物的生长过程中发挥至关重要的作用,蔗糖磷酸合成酶(SPS)是蔗糖合成的关键限速酶。生物信息分析显示,在谷子中,SPS-Si000130m与海藻糖6-磷酸合成酶基因TPS-Si016303m、尿苷二磷酸葡萄糖脱氢酶基因UGD-Si035452m存在显著的相互作用。高通量测序对谷子3种基因的表达谱研究进一步表明,在谷子根、茎、叶、穗中SPS-Si000130m基因与TPS-Si016303m基因的表达模式呈正相关,与UGD-Si0354-52m基因的表达模式呈负相关。但无论是正相关还是负相关,TPS-Si016303m和UGD-Si035452m沿谷子叶片梯度的表达模式均与SPS-Si000130m基因存在差异。SPS-Si000130m的表达集中在叶片光合作用的功能部位,而TPS-Si016303m的转录物在叶片梯度各部位均可检测到,可见即使这两个基因呈现正相关,它们之间仍存在自身独特的表达、调控特点;负相关基因(即UGD-Si035452m和SPS-Si000130m)沿叶片梯度相反的表达模式则反映出植物通过基因表达的区域化,避免这两个酶彼此竞争相同底物,防止无效循环的进行。进一步通过生物信息学软件预测三种蛋白的功能结构域和3D结构则显示,SPS-Si000130m和TPS-Si016303m之间存在相同功能结构域—糖基转移酶功能结构域;而SPS-Si000130m和UGD-Si035452m之间没有相同功能结构域。总之,深入研究3种蛋白功能和结构的特点及它们之间的相互作用,将加深对谷子糖类代谢调控网络的认识,并有助于我们改善谷子品质的研究。Sucrose plays the critical role in the process of plant growth. Sucrose phosphate synthase（SPS） is a key rate-limiting enzyme in sucrose biosynthesis. Bioinformatics analysis showed that there were significant interactions between SPS-Si000130 m and trehalose-6-phosphase（TPS）-Si016303 m as well as between SPS-Si00-0130 m and UDP-glucose-6-dehydrogenase（UGD）-Si035452 m in millet. Studies on high-throughput sequencing on expression profiling of these three genes in millet further indicated that TPS-Si016303 m showed similar expression patterns as SPS-Si000130 m in root, stem, leaf and tassel, whereas UGD-Si035452 m exhibited opposite patterns compared with SPS-Si000130 m. TPS-Si016303 m and UGD-Si035452 m showed different expression patterns from SPS-Si000130 m along leaf developmental gradient. It was found that the expression of SPS-Si000130 m was concentrated on leaf functional regions for photosynthesis, whereas the transcripts of TPS-Si0-16303 m could be detected in all regions along leaf gradient, indicating that even if the genes show positive correlation, they had their own unique expression and regulatory characteristics. The negative correlation of the genes（i.e. SPS-Si000130 m and UGD-Si035452 m）, which showed opposite expression patterns along leaf gradient reflected that plants prevented the two enzymes from competing the same substrate through compartmentalization of the gene expression, thus avoided futile cycle. Further bioinformatics predictions of motifs and 3 D structures of three proteins revealed that both SPS-Si000130 m and TPS-Si016303 m contained the same functional domain-glycosyltransferase domain, whereas no similar functional domain was found between SPS-Si000130 m and UGD-Si035452 m. In short, detailed studies on the functions and structural characteristics of three genes and on their interactions would improve our understanding on the regulatory networks of carbohydrate metabolism, and further facilitate our research for millet quality improvement.

关 键 词：谷子 蔗糖磷酸合成酶 海藻糖6-磷酸合成酶 尿苷二磷酸葡萄糖脱氢酶 蛋白互作 基因表达 

分 类 号：Q943.2[生物学—植物学] S515[农业科学—作物学]