Ruan Jinghua, Wu Meiyu, Ye Xiaogang, Zhao Shuo, Liang Jianshe, Ye Lupeng, You Zhengying, Zhong Boxiong
College of Animal Sciences, Zhejiang University, Hangzhou, China.
College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, China.
Front Genet. 2021 Jan 21;11:592128. doi: 10.3389/fgene.2020.592128. eCollection 2020.
Naked pupa sericin and Naked pupa are two mutant strains of with extremely low or no fibroin production compared to the Qiufeng and Baiyu strains, both of which exhibit very high silk fibroin production. However, the molecular mechanisms by which long non-coding RNAs regulate fibroin synthesis need further study. In this study, we performed high-throughput RNA-seq to investigate lncRNA and mRNA expression profiles in the posterior silk gland of Qiufeng, Baiyu, Nd-s, and Nd silkworms at the third day of the 5th instar. Our efforts yielded 26,767 novel lncRNAs and 6,009 novel mRNAs, the expression levels of silk protein genes and silk gland transcription factors were decreased in Qiufeng vs. Nd-s and Qiufeng vs. Nd, while those of many genes related to autophagy, apoptosis, RNA degradation, ubiquitin-mediated proteolysis and heat shock proteins were increased. Moreover, the expression of a large number of genes responsible for protein synthesis and secretion was significantly decreased in Nd. GO and KEGG analysis results showed that nucleotide excision repair, mRNA surveillance pathways, amino acid degradation, protein digestion and absorption, ER-associated degradation and proteasome pathways were significantly enriched for the Qiufeng vs. Nd-s and Qiufeng vs. Nd comparisons. In conclusion, our findings contribute to the lncRNA and mRNA database of , and the identified differentially expressed mRNAs and lncRNAs help to reveal the molecular mechanisms of low silk production in Nd-s and Nd, providing new insights for improvement of silk yield and elucidation of silk mechanical properties.
裸蛹丝胶和裸蛹是两个突变品系，与秋丰和白玉品系相比，它们的丝素蛋白产量极低或无丝素蛋白产生，而后两者的丝素蛋白产量很高。然而，长链非编码RNA调节丝素蛋白合成的分子机制仍需进一步研究。在本研究中，我们进行了高通量RNA测序，以研究5龄第3天秋丰、白玉、Nd-s和Nd家蚕后部丝腺中的lncRNA和mRNA表达谱。我们共获得了26767个新的lncRNA和6009个新的mRNA，秋丰与Nd-s以及秋丰与Nd相比，丝蛋白基因和丝腺转录因子的表达水平降低，而许多与自噬、凋亡、RNA降解、泛素介导的蛋白水解和热休克蛋白相关的基因表达增加。此外，Nd中大量负责蛋白质合成和分泌的基因表达显著降低。GO和KEGG分析结果表明，在秋丰与Nd-s以及秋丰与Nd的比较中，核苷酸切除修复、mRNA监测途径、氨基酸降解、蛋白质消化和吸收、内质网相关降解和蛋白酶体途径显著富集。总之，我们的研究结果丰富了家蚕的lncRNA和mRNA数据库，所鉴定的差异表达mRNA和lncRNA有助于揭示Nd-s和Nd产丝量低的分子机制，为提高蚕丝产量和阐明蚕丝力学性能提供了新的见解。
