【目的】鉴定中华按蚊Anopheles sinensis CYP6Y亚家族基因,分析它们的结构和特征,推测其可能的功能。【方法】以冈比亚按蚊An.gambiae CYP6Y1作为询问序列,通过双向Blast方法检索中华按蚊转录组中CYP6Y亚家族基因,并通过生物信息学方法分析基因结构、特征及可能的功能。【结果】从中华按蚊转录组测序数据中鉴定出2条CYP6Y亚家族基因,分别命名为AsCYP6Y1(GenBank登录号:KF709397)和AsCYP6Y2(GenBank登录号:KF709398)。序列分析显示,AsCYP6Y1和AsCYP6Y2全长分别为1 713 bp和1 815 bp,分别编码502和526个氨基酸。基因结构分析显示,该亚家族基因仅含有1个相位1型内含子并与其他P450基因形成保守的共线性分布。蛋白结构分析显示,这2个基因编码的蛋白含P450特有的5个特征序列和6个底物结合位点,且均不存在信号肽,其亚细胞定位为细胞质。3D结构分析显示,AsCYP6Y1有18条α螺旋和13股反向平行的β折叠,AsCYP6Y2有19条α螺旋和11股反向平行的β折叠。通过同样的方法,在达林按蚊An.darlingi中也鉴定出2个CYP6Y亚家族基因。系统进化分析显示,AsCYP6Y1和AsCYP6Y2分别与其他3种按蚊的CYP6Y1和CYP6Y2聚成一支,Bootstrap值均大于90%。替换率分析显示,中华按蚊AsCYP6Y1和AsCYP6Y2与其他3种按蚊同源基因的Ka/Ks均小于1。相对进化速率分析显示,中华按蚊CYP6Y和CYP6M亚家族的相对进化速率均显著快于CYP6P亚家族,而CYP6Y和CYP6M亚家族之间没有显著差异。【结论】在中华按蚊和达林按蚊中存在2个CYP6Y亚家族基因,之前在冈比亚按蚊和不吉按蚊An.funestus中也发现2个CYP6Y亚家族基因,表明CYP6Y亚家族基因可能在按蚊属广泛存在,且可能为按蚊属昆虫所特有。
【Aim】 To identify genes of the CYP6Y subfamily in Anopheles sinensis, analyze their structure and characteristics, and deduce their possible functions. 【Method】 The CYP6Ys cDNA transcripts were retrieved and identified by two ways of Blasts using An. gambiae CYP6Y1 as query sequence against the transcriptome data of An. sinensis. The structure, characteristics and possible functions of the CYP6Y genes identified were analyzed using bioinformatics methods. 【Results】 Two genes of the CYP6Y subfamily were identified from An. sinensis transcriptome sequencing data, and named as AsCYP6Y1 (GenBank accession number: KF709397) and AsCYP6Y2 (GenBank accession number: KF709398) , respectively. Sequence analysis showed that AsCYP6Y1 and AsCYP6Y2 are 1 713 bp and 1 815 bp in length, encoding 502 and 526 amino acids, respectively. Gene structure analysis showed that the genes of this subfamily only contain one phase “1” intron and form a conserved synteny with other P450 genes. Protein structure prediction showed that the encoded proteins of these two genes contain five P450 characteristic sequences and six specific substrate binding sites, but have no signal peptide sequence, and are localized in cytoplasm. The 3D structural prediction showed that AsCYP6Y1 has 18 α-helix and 13 anti-parallel β-strands, while AsCYP6Y2 has 19 αhelix and 11 antiparallel βstrands. Two CYP6Y genes were also identified in An. darlingi using the same method. Phylogenetic analysis showed that AsCYP6Y1 and AsCYP6Y2 are grouped with CYP6Y1 and CYP6Y2 of other Anopheles species, respectively, with the bootstrap values greater than 90%. The Ka/Ks ratio analysis showed that the Ka/Ks ratio of AsCYP6Y1 and AsCYP6Y2 compared with CYP6Y1 and CYP6Y2 of other Anopheles species were all less than 1. The relative evolutionary rate test showed that the rates of subfamilies CYP6Y and CYP6M were significantly higher than those of the subfamily CYP6P in An. sinensis, while no significant difference between subfamilies CYP