College of Life Sciences and Medicine, Zhejiang Sci-Tech University, Hangzhou, 310018, China.
Zhejiang Economic & Trade Polytechnic, Hangzhou, 310018, China.
Appl Biochem Biotechnol. 2022 Apr;194(4):1621-1635. doi: 10.1007/s12010-021-03757-9. Epub 2021 Nov 26.
Acetylation is a highly conservative and reversible post-translational modification. Acetylation modification can regulate gene expression by altering protein function and is widely identified in an increasing number of species. Previously, the acetylated proteome of silkworm was identified by combining acetylated polypeptide enrichment with nano-HPLC/MS/MS; the identification revealed that the SP proteins (SPs) were high acetylated. In this study, the acetylation of SP1, one of the SPs, was further confirmed using immunoprecipitation (IP) and Western blotting. Then, we found the acetylation could upregulate SP1 protein expression by enhancing the protein stability. Further research found that the acetylation of SP1 protein can competitively inhibit its ubiquitination and thus improve the stability and cell accumulation of SP1 protein by inhibiting the ubiquitin-mediated proteasome degradation pathway. This result provides a basis for acetylation to regulate the nutrient storage and utilization of silkworm.
乙酰化是一种高度保守和可逆的翻译后修饰。乙酰化修饰可以通过改变蛋白质功能来调节基因表达，并且在越来越多的物种中得到广泛识别。以前，通过结合乙酰化多肽富集和纳升 HPLC/MS/MS 鉴定了家蚕的乙酰化蛋白质组；鉴定结果表明 SP 蛋白（SPs）高度乙酰化。在这项研究中，通过免疫沉淀（IP）和 Western blot 进一步证实了 SPs 之一 SP1 的乙酰化。然后，我们发现乙酰化可以通过增强蛋白质稳定性来上调 SP1 蛋白表达。进一步的研究发现，SP1 蛋白的乙酰化可以通过竞争性抑制其泛素化，从而通过抑制泛素介导的蛋白酶体降解途径来提高 SP1 蛋白的稳定性和细胞积累。该结果为乙酰化调节家蚕的营养物质储存和利用提供了依据。
