家蚕五龄第1天与第4天后部丝腺蛋白质双向电泳图谱比较

Analysis of Two-Dimensional Gel Electrophoresis Patterns of Protein from Posterior Silkgland of Silkworm Bombyx mori on Day 1 and Day 4 in 5th Instar Stage

【目的】家蚕后部丝腺是合成分泌占蚕丝总量75%～80%丝素蛋白的器官,通过后部丝腺蛋白的研究,有利于阐明家蚕分泌丝素蛋白及蚕茧优质、高产的机理。【方法】采用蛋白质双向电泳和图像分析技术,研究了家蚕不同品种五龄第1天和第4天后部丝腺细胞的蛋白质组成变化。【结果】发现各个品种五龄第1天和第4天后部丝腺细胞的蛋白质组成存在差异,但蛋白质水平的差异,远远小于从EST分析得出的基因表达水平的差异;不同家蚕品种,从五龄第1天到第4天,后部丝腺细胞的蛋白质组成的变化规律各不相同。【结论】暗示了家蚕丝素分泌的过程可能受到多种蛋白的调控,不同的品种,在调控位点及调控蛋白上存在着一定的差异,从而导致了不同品种家蚕后部丝腺细胞在分泌丝素能力上的差异。

[Objective] The posterior silkgland of silkworm is a very important organ where fibroin is synthesized and secreted. Since fibroin constructs silk-filament by amount of 75%-80%, the mechanism of fibroin secretion, cocoon quality and high yield can be elucidated by the study on the posterior silkgland. [Method] Using two-dimensional gel electrophoresis （2-DE） and image analysis system, the changes of protein composition in posterior silkgland cell of day 1 （D1） and D4 in the 5th instar stage from various breeds of silkworm Bombyx mori were investigated. [ Result ] Differences were observed between days and breeds and far less than those at the gene level through EST analysis. The change patterns of protein composition from D1 to D4 were diverse in various breeds. [ Conclusion ] The results suggest that the secretion of fibroin is regulated by multi-protein. The site and protein for regulation vary with breeds, which leads to the difference of the capacity of fibroin secretion in the posterior silkgland cell between breeds.