Papers by Author: Si Si Zhao

Abstract: The Bombyx mori serves as model organism among the Lepidoptera insects. In the post-genomic era, in order to study gene function, the profiling of mRNA transcription has become a popular research field. Real-time quantitative RT-PCR (qRT-PCR) has become established as the sensitive method for detecting the expression level of low abundance mRNA, and it usually chooses one or several reference genes to standardize the expression level of target gene. Since the changes in amplification of reference gene can reflect the changes of RNA production, quality or cDNA synthesis efficiency. So choosing an appropriate reference gene can reduce the differences between tested samples. Based on the comparison of Standardization of three frequently-used reference genes (GAPDH, Actin-3, 28srRNA), and decide which is the best way to study gene expression level in silkworm, Bombyx mori.

Abstract: The present study was undertaken to clarify the change of induction of CYP4M5 and CYP4M9 expression level by rutin. In this study, we used dual-spike-in qPCR to examine expression profiles of the silkworm Bombyx mori CYP4M5 and CYP4M9 genes in the larval midgut and fatbody after exposure to rutin. In organization-course study, rutin at middle concentration (5×10-2ng/µL) caused significant upregulation of CYP4M5 and CYP4M9 genes at early time point (2h) in fatbody, higher concentration (5×10-1ng/µL) did secondly, while lower concentration (5×10-3ng/µL) caused little change. In the midgut of silkworm, rutin in all concentrations didn't affect the expression of the two genes. These findings showed that induction of CYP4M5 and CYP4M9 expression level by rutin are concentration depended and tissue-specific.Collectively, CYP4M5 and CYP4M9 genes may have some relationships with metabolism of rutin in silkworm.

Abstract: In order to explore the roles of Bombyx mori glutathione S-transferase gene (BmGST) in detoxification and resistance to insecticides, we used real-time PCR method to detect the transcription levels of five BmGST genes in different tissues of the 5th instar larvae feeding on sodium fluoride treated mulberry leaves. The detection results were normalized by using 3 internal reference genes. The results indicated that the transcription levels of BmGSTs were different in various tissues. Transcription of BmGST genes could be induced by NaF, The normalized data with the above 3 internal reference genes indicated that, it is very important to choose adequate internal reference genes so as to ensure the reliability of the detection results.