State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing 400716, China; Wenzhou Institute, University of Chinese Academy of Sciences, Wenzhou, Zhejiang 325001, China.
State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing 400716, China; Key Laboratory for Sericulture Functional Genomics and Biotechnology of Agricultural Ministry, Southwest University, Chongqing 400716, China.
Int J Biol Macromol. 2023 Jul 1;242(Pt 4):124931. doi: 10.1016/j.ijbiomac.2023.124931. Epub 2023 May 30.
Endomitosis is involved in developmental processes associated with an increase in metabolic cell activity, which is characterized by repeated rounds of DNA replication without cytokinesis. Endomitosis cells are widespread in protozoa, plants, animals and humans. Endomitosis cell cycle is currently viewed as a variation of the canonical cell cycle and transformed from mitotic cell cycle. However, the meaningful question about how endomitosis transformed from mitosis is still unclear. Herein, we identified a novel transcription factor in silk glands, ZFP67, which is gradually reduced in silk glands during the transition of mitosis to endomitosis. In addition, over-expressed ZFP67 in silk glands led to the transition delayed. And, knock-out of ZFP67 led to abnormal chromatin division and unsuccessful cell division. These data reveled that ZFP67 played an important role in transition of mitosis to endomitosis. Furthermore, ZFP67 can regulate the transcription of cyclin B, a key cyclin related to cell division and G2/M phase, which is demonstrated by chromatin immunoprecipitation and dual luciferase reporter system in this article. In conclusion, it can be speculated that the decreasing expression of ZFP67 in silk glands during the transition stage of mitosis-to-endomitosis resulted in the lack of cyclin B, which further led to unsuccessful cytokinesis and then promoted the transition from mitosis to endomitosis of silk gland cells.
有丝分裂内发生于与代谢细胞活性增加相关的发育过程中，其特征在于没有胞质分裂的重复 DNA 复制。有丝分裂内发生细胞广泛存在于原生动物、植物、动物和人类中。有丝分裂内发生细胞周期目前被视为经典细胞周期的一种变体，并由有丝分裂周期转化而来。然而，有丝分裂如何转化为有丝分裂内发生的这个有意义的问题仍然不清楚。在此，我们在丝腺中鉴定到一个新的转录因子 ZFP67，其在丝腺中从有丝分裂向有丝分裂内发生的转变过程中逐渐减少。此外，在丝腺中过表达 ZFP67 导致转变延迟。并且，敲除 ZFP67 导致异常染色质分裂和细胞分裂失败。这些数据表明 ZFP67 在有丝分裂向有丝分裂内发生的转变中发挥了重要作用。此外，ZFP67 可以调节细胞周期蛋白 B 的转录，细胞周期蛋白 B 是与细胞分裂和 G2/M 期相关的关键周期蛋白，这在本文的染色质免疫沉淀和双荧光素酶报告系统中得到了证明。总之，可以推测 ZFP67 在丝腺有丝分裂向有丝分裂内发生转变阶段的表达减少导致细胞周期蛋白 B 的缺乏，这进一步导致胞质分裂失败，从而促进丝腺细胞从有丝分裂向有丝分裂内发生的转变。
