黄瓜AQP基因家族的鉴定与生物信息学分析

Identification and bioinformatics analysis of AQP gene family in Cucumis sativus

【目的】深入研究黄瓜Cucumis sativus水通道蛋白(aquaporin,AQP)基因家族(CsAQP)的相关功能。【方法】通过全基因组分析技术鉴定其家族成员,对其蛋白质理化性质、系统进化关系、选择压力、基因结构、保守基序、顺式作用元件、蛋白质互作进行分析。【结果】黄瓜基因组共有33个AQP基因,含有2~5个数量不等的外显子,在染色体上不均匀分布;根据物种进化关系将黄瓜AQP基因家族划分为5个亚家族;基因组重复序列分析表明:5号和6号染色体上各有2~3对基因串联重复;计算这些基因的同义替换(synonymous,K_(s))和非同义替换(nonSynonymous,K_(a))的比率,结果显示均小于1,表明其进化受纯化选择作用;顺式作用调控元件分析发现,大部分基因启动子区所含元件与激素调节、光响应、胁迫密切相关。【结论】通过黄瓜全基因组扫描,获得黄瓜基因组的33个AQP家族成员,分属于5个亚族,映射于7条染色体上。上游启动子区含逆境相关作用元件,且部分基因参与串联复制,历经纯化选择。

[Objective]This study aims to explore the functions of aquaporin(AQP)gene family(CsAQP)in Cucumis sativus.[Method]The family members were identified by whole genome analysis,and their protein physical and chemical properties,phylogenetic relationships,selection pressure,gene structure,conserved motifs,cis-acting elements and protein interactions were analyzed.[Result]There were 33 AQP genes in C.sativus genome,which contained 2−5 exons and were unevenly distributed on chromosomes.According to the evolutionary relationship,the AQP gene family was divided into 5 subfamilies.Genome repeat analysis showed that there were 2−3 pairs of gene tandem repeats on chromosome 5 and 6 respectively.The ratios of synonymous substitution(K_(s))and nonsynonymous substitution(K_(a))of these genes were calculated.The results showed that they were less than 1,indicating that their evolution was affected by purification selection.The analysis of cis-acting regulatory elements showed that most of the elements in the gene promoter region were closely related to hormone regulation,light response,and stress resistance.[Conclusion]Through the whole genome scanning,33 AQP family members are obtained from C.sativus genome,which belong to 5 subfamilies and map on 7 chromosomes.The upstream promoter region contains stress-related elements,and some genes participate in tandem replication and undergo purification selection.