The Sericultural and Apicultural Research Institute, Yunnan Academy of Agricultural Sciences, Mengzi, Yunnan, China.
The Key Sericultural Laboratory of Shaanxi, Ankang University, Ankang, Shaanxi, China.
PLoS One. 2021 Dec 30;16(12):e0261918. doi: 10.1371/journal.pone.0261918. eCollection 2021.
Yun7Ge is a giant egg mutant found in the silkworm variety Yun7. In comparison with the giant mutant Ge, the eggs of Yun7Ge are larger. The number of laid eggs and hatching rate of Yun7Ge are reduced, which is not conducive to reproduction. In this work, the target gene controlling giant egg trait is located on the Z chromosome and was determined through genetic analysis. Transcriptome results showed that phytanoyl-CoA dioxygenase domain-containing protein 1 (PHYHD1) on the Z chromosome was silenced, and the 25 chorion genes on chromosome 2 were remarkably downregulated. Sequence analysis showed that the 73.5 kb sequence including the PHYHD1 was replaced by a ~3.0 kb sequence. After knocking out the PHYHD1 by using CRISPR/Cas9, the chorion genes were significantly downregulated. Hence, the silencing of PHYHD1 leads to the downregulation of many chorion protein genes, thus directly causing giant eggs.
云 7 号巨型卵突变体是在蚕品种云 7 中发现的。与巨型突变体 Ge 相比，云 7 号巨型卵的卵更大。云 7 号巨型卵的产卵数和孵化率降低，不利于繁殖。在这项工作中，控制巨型卵特性的靶基因位于 Z 染色体上，并通过遗传分析确定。转录组结果表明，Z 染色体上的植烷酰辅酶 A 双加氧酶结构域蛋白 1（PHYHD1）被沉默，第 2 号染色体上的 25 个卵壳基因显著下调。序列分析表明，包括 PHYHD1 的 73.5 kb 序列被一个约 3.0 kb 的序列取代。利用 CRISPR/Cas9 敲除 PHYHD1 后，卵壳基因显著下调。因此，PHYHD1 的沉默导致许多卵壳蛋白基因下调，从而直接导致巨型卵的产生。
