Cancer Biology and Inflammatory Disorder Division, CSIR-Indian Institute of Chemical Biology, Kolkata, India.
Biochemistry and Molecular Biology, Southern Illinois University, USA.
FASEB J. 2023 Mar;37(3):e22815. doi: 10.1096/fj.202201533R.
Mutations in Cellular Communication Network Factor 6 (CCN6) are linked to the debilitating musculoskeletal disease Progressive Pseudo Rheumatoid Dysplasia (PPRD), which disrupts mobility. Yet, much remains unknown about CCN6 function at the molecular level. In this study, we revealed a new function of CCN6 in transcriptional regulation. We demonstrated that CCN6 localizes to chromatin and associates with RNA Polymerase II in human chondrocyte lines. Using zebrafish as a model organism we validated the nuclear presence of CCN6 and its association with RNA Polymerase II in different developmental stages from 10 hpf embryo to adult fish muscle. In concurrence with these findings, we confirmed the requirement of CCN6 in the transcription of several genes encoding mitochondrial electron transport complex proteins in the zebrafish, both in the embryonic stages and in the adult muscle. Reduction in the expression of these genes upon morpholino-mediated knockdown of CCN6 protein expression led to reduced mitochondrial mass, which correlated with defective myotome organization during zebrafish muscle development. Overall, this study suggests that the developmental musculoskeletal abnormalities linked with PPRD could be contributed at least partly by impaired expression of genes encoding mitochondrial electron transport complexes due to defects in CCN6 associated transcriptional regulation.
细胞通讯网络因子 6(CCN6)中的突变与使人衰弱的肌肉骨骼疾病进行性假性类风湿发育不良(PPRD)有关,该疾病会破坏运动能力。然而,关于 CCN6 在分子水平上的功能,仍有许多未知之处。在这项研究中,我们揭示了 CCN6 在转录调控中的一个新功能。我们证明 CCN6 定位于染色质,并与人软骨细胞系中的 RNA 聚合酶 II 相关联。我们使用斑马鱼作为模型生物,验证了 CCN6 在从 10 hpf 胚胎到成年鱼肌肉的不同发育阶段中的核存在及其与 RNA 聚合酶 II 的关联。与这些发现一致,我们证实了 CCN6 在几种编码线粒体电子传递复合物蛋白的基因的转录中是必需的,无论是在胚胎阶段还是在成年肌肉中。CCN6 蛋白表达的 morpholino 介导敲低导致这些基因的表达减少,导致线粒体质量减少,这与斑马鱼肌肉发育过程中肌节组织缺陷相关。总的来说,这项研究表明,与 PPRD 相关的发育性肌肉骨骼异常至少部分可能是由于 CCN6 相关的转录调节缺陷导致编码线粒体电子传递复合物的基因表达受损所致。