Effect of depletion of the Gne gene in Sol8 murine muscle cells

GNE myopathy is an adult onset neuromuscular disorder characterized by slowly progressive distal and proximal muscle weakness, caused by missense recessive mutations in the GNE gene. Although the encoded bifunctional enzyme is well known as the limiting factor in the biosynthesis of sialic acid, no clear mechanisms have been recognized to account for the muscle atrophic pathology, and novel functions for GNE have been hypothesized. No reliable animal model is available for the disease and cellular models from GNE myopathy patients' muscle cells (expressing the mutated protein) are less informative than expected. In order to broaden our knowledge on GNE functions in muscle, we have generated a Gne knock out murine muscle cell lineage to identify the events resulting from the total lack of the protein. A thorough multi-omics analysis of both systems including transcriptomics, proteomics, phosphoproteomics and ubiquitination, unraveled novel pathways for Gne, in particular its involvement in cell cycle control and in the DNA damage/repair pathway.The elucidation of fundamental mechanisms of Gne in normal muscle may contribute to the identification of the disrupted functions in GNE myopathy, thus, to the definition of novel biomarkers and possible therapeutic targets for this disease. Comparative gene expression profiling analysis of RNA-seq data for Sol8 Gne KO and WT cells

GNE肌病（GNE myopathy）是一种成人起病的神经肌肉疾病，以缓慢进展的远端及近端肌无力为特征，由GNE基因的隐性错义突变引发。尽管其编码的双功能酶作为唾液酸生物合成的限速因子已被广泛认知，但目前仍未明确可解释肌肉萎缩病理的清晰机制，学界已针对GNE提出全新功能假说。目前尚无该病的可靠动物模型，而源自GNE肌病患者肌肉细胞（表达突变蛋白）的细胞模型的研究价值未达预期。为拓宽我们对GNE在肌肉中功能的认知，我们构建了Gne敲除小鼠肌肉细胞系，以鉴定该蛋白完全缺失所诱发的生物学事件。对两种实验系统开展的全面多组学（multi-omics）分析，涵盖转录组学（transcriptomics）、蛋白质组学（proteomics）、磷酸化蛋白质组学（phosphoproteomics）及泛素化修饰组学（ubiquitination），揭示了Gne的全新调控通路，特别是其在细胞周期调控以及DNA损伤/修复通路中的参与作用。阐明Gne在正常肌肉中的核心作用机制，或有助于识别GNE肌病中功能紊乱的靶点，进而为该疾病确定新型生物标志物及潜在治疗靶点。本研究针对Sol8 Gne敲除（KO）与野生型（WT）细胞的RNA测序（RNA-seq）数据开展了比较基因表达谱分析