向日葵HaFATB基因的生物信息学和表达分析

Bioinformatics and Expression Analysis of HaFATB Gene in Sunflower

向日葵油中不饱和脂肪酸主要为油酸和亚油酸,当不饱和脂肪酸总量一定,油酸含量越高,营养价值和品质越好,且不易氧化腐败。FATB编码脂肪酸-酰基载体蛋白硫酯酶B,将脂肪酸链从酰基载体蛋白中释放出自由的脂肪酸。本研究对向日葵HaFATB编码蛋白进行了生物信息学的分析,预测HaFATB编码蛋白为碱性蛋白且为亲水性蛋白,蛋白二级结构为无规则卷曲,预测亚细胞定位于叶绿体。系统进化分析发现,HaFATB基因与同属菊科的青蒿(Artemisia annua L.)FATB进化关系最近,序列相似性高达88%。HaFATB组织特异性表达分析结果表明,HaFATB在茎、管状花和根中表达最低,其次是叶和舌状花,在部分发育时期的种子中表达较高,HaFATB在高、低油酸向日葵种子不同发育阶段表达变化趋势明显不同,但均在种子发育前期表达较低,总的来说低油酸种子中表达量要高于高油酸种子,因此认为Ha FATB的表达量很可能影响着向日葵种子的油酸含量。

The main unsaturated fat ty acids in sunflower oil are oleic acid and linoleic acid.When the total amount of unsaturated fatty acids is certain,the higher the oleic acid content,the better the nutritional value and quality,and is not easy to oxidize and corrupt.FATB encodes fatty acyl-ACP thioesterase B,which releases free fatty acids from acyl carrier protein.In this study,the bioinformatics analysis of HaFATB encoded protein in sunflower was carried out.It was predicted that the protein encoded by HaFATB was basic protein and hydrophilic protein.The secondary structure of the protein encoded by HaFATB was irregular coil,and the subcellular localization was predicted in the chloroplast.Phylogenetic analysis showed that HaFATB was closely related to Artemisia annua L.FATB,and the sequence similarity was as high as 88%.The results of tissue-specific expression analysis of HaFATB showed that the expression of HaFATB was the lowest in stems,tubular flowers and roots,followed by leaves and ligulate flowers,and the expression of HaFATB was higher in some developmental stages of seeds.The expression trend of HaFATB in different developmental stages of high and low oleic acid sunflower seeds was obviously different,but the expression of HaFATB were both low in the early stage of seed development.In general,the expression of low oleic acid seeds was higher than that of high oleic acid seeds.Therefore,it is suggested that the expression level of HaFATB may affect the oleic acid content of sunflower seeds.