Acetylation is an important, highly conserved, and reversible post‐translational modification of proteins. Previously, we showed by nano‐HPLC/MS/MS that many nutrient storage proteins in the silkworm are acetylated. Among these proteins, most of the known 30K proteins were shown to be acetylated, including 23 acetylated 30K proteins containing 49 acetylated sites (Kac), indicating the importance of the acetylation of 30K proteins in silkworm. In this study, Bm30K‐3, a 30K protein containing three Kac sites, was further assessed in functional studies of its acetylation. Increasing the level of Bm30K‐3 acetylation by adding the deacetylase inhibitor trichostatin A (TSA) increased the levels of this protein and further inhibited cellular apoptosis induced by H₂O₂. In contrast, decreasing the level of acetylation by adding the acetylase inhibitor C646 could reduce the level of Bm30K‐3 and increase H₂O₂‐induced apoptosis. Subsequently, BmN cells were treated with CHX and MG132, and increasing the acetylation level using TSA was shown to inhibit protein degradation and improve the stability of Bm30K‐3. Furthermore, the acetylation of Bm30K‐3 could compete with its ability to be ubiquitinated, suggesting that acetylation could inhibit the ubiquitin‐mediated proteasome degradation pathway, improving the stability and accumulation of proteins in cells. These results further indicate that acetylation might regulate nutrition storage and utilization in Bombyx mori, which requires further study.

中文翻译：

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Bm30K-3的稳定性和抗凋亡活性可以通过家蚕Bombyx mori中的赖氨酸乙酰化来提高。

乙酰化是重要的，高度保守的且可逆的蛋白质翻译后修饰。以前，我们通过纳米HPLC / MS / MS证明了家蚕中的许多营养储藏蛋白都被乙酰化。在这些蛋白质中，大多数已知的30K蛋白显示为乙酰化的，包括23个乙酰化的30K蛋白，其中包含49个乙酰化位点（Kac），这表明30K蛋白在蚕中被乙酰化的重要性。在这项研究中，Bm30K-3（一种包含三个Kac位点的30K蛋白）在其乙酰化功能研究中得到了进一步评估。通过添加脱乙酰基酶抑制剂曲古抑菌素A（TSA）来提高Bm30K-3乙酰化水平，可增加该蛋白的水平，并进一步抑制H ₂ O ₂诱导的细胞凋亡。相反，通过添加乙酰酶抑制剂C646降低乙酰化水平可以降低Bm30K-3的水平并增加H ₂ O ₂诱导的细胞凋亡。随后，用CHX和MG132处理BmN细胞，并显示使用TSA增加乙酰化水平可抑制蛋白质降解并提高Bm30K-3的稳定性。此外，Bm30K-3的乙酰化作用可能与其泛素化能力竞争，这表明乙酰化作用可以抑制泛素介导的蛋白酶体降解途径，从而改善细胞中蛋白质的稳定性和积累。这些结果进一步表明乙酰化可能调节家蚕中的营养存储和利用，这需要进一步研究。