家蚕血细胞特异表达新基因Bm04862的鉴定及表达

Identification and characterization of a novel hemocyte specific gene Bm04862 in silkworm, Bombyx mori

摘要:

通过家蚕组织芯片数据筛选得到家蚕血细胞特异表达基因Bm04862，并首次对该基因进行了克隆与鉴定。应用RACE技术获得该基因全长，并对其进行生物信息学分析。Bm4862基因开放阅读框819 bp，共编码273 个氨基酸残基，预测其为跨膜蛋白；通过qRT-PCR技术对其时空表达情况进行分析；结果显示Bm04862基因在家蚕血细胞中特异高表达，并在4龄眠期和预蛹2 d时达到表达高峰；构建Bm04862真核表达载体，转染Sf9细胞分析其蛋白的亚细胞定位情况，结果表明其定位于细胞核膜和部分细胞质中。此外，用大肠杆菌刺激蚕体24 h后，Bm04862基因表达水平显著上调，表明大肠杆菌可以诱导该基因的表达，由此推测该基因可能参与家蚕的免疫应答。这为深入研究该基因在家蚕免疫反应中的功能提供了参考。

Abstract:

Bm04862 is a novel hemocyte-specific gene, which has been identified and cloned through the microarray data in silkworm, Bombyx mori. Initially, we successfully obtained the full-length cDNA sequence of Bm04862 via the rapid amplification of cDNA ends (RACE). The sequence consists of an open reading frame (ORF) with 819 bp, which could encode 273 amino acid residues. The bioinformatics analysis predicted that Bm04862 was a transmembrane protein. Furthermore, qRT-PCR analysis revealed that the expression of Bm04862 was specifically detected in hemocyte and reached a peak at L4M and PP2 stage. Bm04862 was overexpressed in Sf9 insect cells, and the cellular localization indicated that Bm04862 was specifically located in cytoplasm and nuclei membrane. Interestingly, the expression of Bm04862 increased dramatically after challenged with Escherichia coli for 24 hours, which predicted its potential role in the innate immune system. Overall, this study could provide the fundamental knowledge for further research.