Abstract

Starch is synthesized through coordinated interactions of a suite of biosynthetic enzymes, including ADP-glucose pyrophosphorylases (TaAGP), granule-bound starch synthases (TaGBSS), starch synthases (TaSS), starch branching enzymes (TaSBE), and starch degradation enzymes (TaDBE). The genes involved in starch biosynthesis have not been extensively studied in common wheat. In an effort to isolate the sequences of genes responsible for starch biosynthesis in common wheat, we identified 57 genes. These genes included two types of TaAGPL located on wheat homoeologous groups 1 and 5; two types of TaAGPS located on groups 5 and 7; TaGBSSI located on chromosomes 4A, 7A, and 7D; TaGBSSII located on group 2; two types of TaISA located on groups 5 and 7; TaPUL located on group 7; three types of TaSBE located on groups 2 and 7; TaSSI located on group 7; TaSSII-1 located on group 1; TaSSII-2 located on group 6; TaSSII-3 located on group 7; TaSSIII-1 located on group 2; TaSSIII-2 located on group 1; and TaSSIV located on group 1. Wheat group 7 had the largest number of these genes. Phylogenetic analysis indicated that common wheat was closely related to Brachypodium, but relatively distant from rice and Sorghum. In silico expression-analysis in different tissues revealed that most of the genes were highly expressed in reproductive tissues, but expression was relatively low in all other tissues. Twelve genes (TaGBSSII-2, TaISA-5, TaSBE-2.1 and TaISA-7) were up-regulated after drought stress for 6 h, and only six genes (TaPUL-7 and TaISA-7) were up-regulated after heat stress for 6 h. This information will be useful for genetic manipulation of starch-biosynthesis genes to develop improved cultivars with high yield and good quality.

中文翻译：

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普通小麦淀粉生物合成基因的全基因组鉴定和表达谱分析

摘要

淀粉是通过一系列生物合成酶（包括ADP-葡萄糖焦磷酸酶（TaAGP），颗粒结合淀粉合酶（TaGBSS），淀粉合酶（TaSS），淀粉分支酶（TaSBE）和淀粉降解酶（TaDBE）的协同相互作用而合成的。）。在普通小麦中，尚未广泛研究涉及淀粉生物合成的基因。为了分离普通小麦中负责淀粉生物合成的基因序列，我们鉴定了57个基因。这些基因包括位于小麦同源组1和5上的两种类型的TaAGPL。位于第5组和第7组的两种类型的TaAGPS；TaGBSSI位于染色体4A，7A和7D上; TaGBSSII位于第2组；位于第5组和第7组的两种TaISA类型；TaPUL位于第7组；位于第2组和第7组的三种TaSBE类型；TaSSI位于第7组；TaSSII-1位于第1组；TaSSII-2位于第6组；TaSSII-3位于第7组；TaSSIII-1位于第2组；TaSSIII-2位于第1组；而TaSSIV位于第1组。小麦第7组的这些基因数量最多。系统发育分析表明普通小麦与Brachypodium密切相关。，但与稻米和高粱的距离相对较远。在不同组织中进行的计算机表达分析表明，大多数基因在生殖组织中高度表达，但在所有其他组织中表达相对较低。干旱胁迫6h后有12个基因（TaGBSSII-2，TaISA-5，TaSBE-2.1和TaISA-7）上调，而只有6个基因（TaPUL-7和TaISA-7）在干旱胁迫下上调。持续6小时。该信息将有助于淀粉生物合成基因的遗传操作，以开发高产，优质的改良品种。