John Rince, Atri Yama, Chand Vaibhav, Jaiswal Neha, Raj Kritika, Nag Alo
Department of Biochemistry, University of Delhi South Campus, New Delhi, India.
FEBS Lett. 2017 Nov;591(21):3507-3522. doi: 10.1002/1873-3468.12864. Epub 2017 Oct 23.
Cytoglobin (Cygb) is a cellular haemoprotein belonging to the globin family with ambiguous biological functions. Downregulation of Cygb in many cancers is indicative of its tumour-suppressive role. This is the first report showing the cell cycle regulation of Cygb, which was found to peak at G1 and rapidly decline in S phase. Importantly, Skp2-mediated degradation of Cygb was identified as the key mechanism for controlling its oscillating levels during the cell cycle. Moreover, overexpression of Cygb stimulates hypophosphorylation of Rb causing delayed cell cycle progression. Overall, the study reveals a novel mechanism for the regulated expression of Cygb and also assigns a new role to Cygb in cell cycle control.
细胞珠蛋白（Cygb）是一种属于珠蛋白家族的细胞血红蛋白，其生物学功能尚不明确。在许多癌症中，Cygb的下调表明其具有肿瘤抑制作用。这是首份显示Cygb细胞周期调控的报告，发现其在G1期达到峰值，并在S期迅速下降。重要的是，Skp2介导的Cygb降解被确定为在细胞周期中控制其振荡水平的关键机制。此外，Cygb的过表达刺激Rb的低磷酸化，导致细胞周期进程延迟。总体而言，该研究揭示了Cygb调控表达的新机制，并赋予了Cygb在细胞周期控制中的新作用。
