Zeng Wenhui, Wang Riyuan, Zhang Tianyang, Gong Chunying, Zuo Weidong, Liu Rongpeng, Ou Yao, Xu Hanfu
State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, China.
College of Biotechnology, Southwest University, Chongqing, China.
PLoS One. 2017 Aug 9;12(8):e0182690. doi: 10.1371/journal.pone.0182690. eCollection 2017.
The transcriptional coactivator Yorkie(Yki), is a critical downstream effector of the Hippo(Hpo) signaling pathway that controls organ size through the regulation of cell proliferation and apoptosis. During the past ten years the biological function of Yki has been studied extensively in Drosophila and a few other insects, however, little is known about it in the silkworm, Bombyx mori, a major research model of lepidopteran insect. Here, we describe the isolation, characterization and expression of the B. mori Yki ortholog, BmYki. The coding sequence of the BmYki was 1314 bp in length, encoding a protein of 437 amino acids containing two conserved WW domains. BmYki transcripts were ubiquitous but not abundant in all detected tissues and developmental stages. Comparatively, it was expressed at pretty high level in silk glands and at the stage of fifth-instar day-3 larvae. Overexpression of BmYki in cultured B. mori embryonic cells significantly promoted transcription of genes associated with cell proliferation and apoptosis, indicating that BmYki functions in the regulation of organ growth-related biological processes. Interestingly, transcription of silk protein-coding genes and transcription factors regulating the synthesis of silk proteins was downregulated remarkably, suggesting that BmYki was involved in the regulation of silk protein synthesis. This study provides new insights into the role of BmYki in Hpo pathway regulation in silkworm.
转录共激活因子Yorkie（Yki）是Hippo（Hpo）信号通路的关键下游效应因子，通过调节细胞增殖和凋亡来控制器官大小。在过去十年中，Yki的生物学功能已在果蝇和其他一些昆虫中得到广泛研究，然而，对于鳞翅目昆虫的主要研究模型家蚕来说，人们对其了解甚少。在此，我们描述了家蚕Yki直系同源基因BmYki的分离、特征及表达情况。BmYki的编码序列长度为1314 bp，编码一个含有437个氨基酸的蛋白质，该蛋白质包含两个保守的WW结构域。BmYki转录本在所有检测的组织和发育阶段均普遍存在但丰度不高。相比之下，它在丝腺中以及五龄第三天幼虫阶段表达水平相当高。在培养的家蚕胚胎细胞中过表达BmYki显著促进了与细胞增殖和凋亡相关基因的转录，表明BmYki在调节器官生长相关生物学过程中发挥作用。有趣的是，丝蛋白编码基因以及调节丝蛋白合成的转录因子的转录显著下调，这表明BmYki参与了丝蛋白合成的调节。本研究为BmYki在家蚕Hpo信号通路调控中的作用提供了新的见解。
