醛氧化酶(aldehyde oxidases,AO,EC1.2.3.1)是属于钼-黄素酶(molybdo-flavoenzymes,MFEs)家族的一类蛋白酶。为了探讨该酶在家蚕Bombyxmori中的功能,本研究对家蚕醛氧化酶基因(BmAOXs)家族进行了鉴定和分析。以其他物种AO基因序列检索家蚕全基因组数据库,获得了8个BmAOX候选基因,均具有醛氧化酶保守的功能域。进化分析表明,BmAOX与其他昆虫AO聚为一簇。RT-PCR分析结果显示:BmAOX1,BmAOX2,BmAOX3,BmAOX5具有很强的组织特异性 而BmAOX4,BmAOX6,BmAOX7,BmAOX8则在蛹和成虫的多个组织中均有表达,提示它们在家蚕生理代谢活动中起重要作用。利用Native-PAGE和活性染色方法,对BmAOX编码的蛋白进行检测,结果表明:家蚕蛹中有5种有活性的醛氧化酶,而成虫中有6种,各组织中均有有活性的BmAOX,只是种类和活性水平有所不同。本研究结果为深入探讨BmAOX家族的功能奠定了基础。
Aldehyde oxidases (AO,EC 1.2.3.1) are a group of protease belonging to the large family of molybdo-flavoenyzme (MFE). In order to research the function of these proteases,aldehyde oxidase genes of the silkworm,Bombyx mori (BmAOXs) were identified and analyzed in this study. Eight candidate genes of BmAOXs sharing the conservative domain with aldehyde oxidases from other species were identified based on the silkworm genomic database. Phylogenetic analysis indicated that BmAOXs were clustered into a cluster with AO proteins of other insects. The results of RT-PCR analysis showed that BmAOX1,BmAOX2,BmAOX3 and BmAOX5 were highly tissue-specific BmAOX4,BmAOX6,BmAOX7 and BmAOX8,however,showed a broad expression profile in different tissues of both pupa and adult,suggesting that they may play important roles in the silkworm metabolism. By Native-PAGE and active staining,five and six active aldehyde oxidases were detected in tissues of pupa and adult of the silkworm,respectively,but they were in different types and activity levels. These results could provide insights into the further functional research on BmAOX gene family.