中华蜜蜂mab-21基因序列分析及表达特征

Sequence analysis and mRNA expression of mab-21 gene in the Chinese honeybee,Apis cerana cerana( Hymenoptera: Apidae)

【目的】探究中华蜜蜂Apis cerana cerana Male abnomal 21(mab-21)基因在不同发育阶段的表达特性及染螨条件下mab-21基因表达变化规律。【方法】本研究利用RT-PCR方法,克隆了中华蜜蜂mab-21的基因编码区;采用荧光定量PCR方法检测了中华蜜蜂mab-21在不同发育时期(新出房蜂、哺育蜂、守卫蜂及采集蜂)工蜂头部中mRNA的表达量以及接种大蜂螨Varroa destructor前后mab-21基因的表达变化。【结果】克隆获得中华蜜蜂mab-21c DNA,命名为Accmab21(Gen Bank登录号KR000001)。序列分析显示,该编码区开放阅读框长为1 098 bp,编码365个氨基酸,推测的编码蛋白的相对分子量和等电点分别为41.63 k D和8.53。系统发育分析表明中华蜜蜂mab-21与西方蜜蜂Apis mellifera mab-21、小蜜蜂Apis florea mab-21和熊蜂Bombus impatiens mab-21聚成一支。该基因在中华蜜蜂工蜂的不同发育时期均有表达,其中哺育蜂阶段显著高于新出房蜂、守卫蜂和采集蜂(P<0.05)。接种大蜂螨后,哺育蜂和守卫蜂中mab-21基因的表达下降显著(P<0.05);而在新出房蜂和采集蜂中表达量变化不显著。【结论】该基因可能与中华蜜蜂抗螨行为相关。

【Aim】The aim of this study is to clone the full-length c DNA of mab-21 gene in the head of the Chinese honeybee,Apis cerana cerana,and then to analyze its expression characteristics in different developmental stages of the workers and after infection of mites,in attempt to provide a theoretical support for revealing the resistance mechanism of A. cerana cerana to Varroa mites. 【Methods 】The c DNA sequence of mab-21 in A. cerana cerana was cloned by RT-PCR,and a quantitative analysis of its expression level in the head of workers at different developmental stages( newly emerged bee,nurse,guarder and forager) and after infection of Varroa destructor mites was conducted using real-time PCR.【Results】The c DNA sequence of mab-21 was cloned from A. cerana cerana,and named as Accmab21( Gen Bank accession no. KR000001). Its open reading frame( ORF) is 1 098 bp in length,encoding395 amino acids with the predicted molecular weight of 41. 63 k D and the theoretical isoelectric point of8. 53. Phylogenetic analysis indicated that mab-21 of A. cerana cerana,A. mellifera,A. florea and Bombus impatiens gather in the same clade. The mab-21 transcript was clearly detected in different developmental stages of the workers of A. cerana cerana,and was significantly higher in nurses than in other stages( P < 0. 05). After being inoculated with V. destructor,the expression of mab-21 in the nurses and guarders significantly decreased as compared to the control( P < 0. 05),but the expression level of mab-21 showed no obvious regularity in newly emerged bees and foragers. 【Conclusion】These results suggest that mab-21 may be involved in the resistance to mites in A. cerana cerana.