Stead Connor A, Hesketh Stuart J, Bennett Samuel, Sutherland Hazel, Jarvis Jonathan C, Lisboa Paulo J, Burniston Jatin G
Research Institute for Sport & Exercise Sciences, Liverpool John Moores University, Liverpool L3 3AF, UK.
Department of Applied Mathematics, Liverpool John Moores University, Liverpool L3 3AF, UK.
Proteomes. 2020 May 11;8(2):10. doi: 10.3390/proteomes8020010.
Differences in the protein composition of fast- and slow-twitch muscle may be maintained by different rates of protein turnover. We investigated protein turnover rates in slow-twitch soleus and fast-twitch plantaris of male Wistar rats (body weight 412 ± 69 g). Animals were assigned to four groups ( = 3, in each), including a control group (0 d) and three groups that received deuterium oxide (DO) for either 10 days, 20 days or 30 days. DO administration was initiated by an intraperitoneal injection of 20 μL of 99% DO-saline per g body weight, and maintained by provision of 4% (/) DO in the drinking water available ad libitum. Soluble proteins from harvested muscles were analysed by liquid chromatography-tandem mass spectrometry and identified against the SwissProt database. The enrichment of DO and rate constant () of protein synthesis was calculated from the abundance of peptide mass isotopomers. The fractional synthesis rate (FSR) of 44 proteins in soleus and 34 proteins in plantaris spanned from 0.58%/day (CO1A1: Collagen alpha-1 chain) to 5.40%/day NDRG2 (N-myc downstream-regulated gene 2 protein). Eight out of 18 proteins identified in both muscles had a different FSR in soleus than in plantaris ( < 0.05).
快肌和慢肌蛋白质组成的差异可能由不同的蛋白质更新率维持。我们研究了雄性Wistar大鼠（体重412±69 g）慢肌比目鱼肌和快肌跖肌中的蛋白质更新率。将动物分为四组（每组 = 3），包括一个对照组（0天）和三个接受氧化氘（DO）处理10天、20天或30天的组。通过腹腔注射每克体重20 μL 99%的DO生理盐水开始给予DO，并通过随意提供含4%（/）DO的饮用水来维持。对收获肌肉中的可溶性蛋白质进行液相色谱 - 串联质谱分析，并根据SwissProt数据库进行鉴定。根据肽质量同位素异构体的丰度计算DO的富集和蛋白质合成的速率常数（）。比目鱼肌中44种蛋白质和跖肌中34种蛋白质的分数合成率（FSR）范围从0.58%/天（CO1A1：胶原蛋白α-1链）到5.40%/天（NDRG2：N - myc下游调节基因2蛋白）。在两块肌肉中鉴定出的18种蛋白质中有8种在比目鱼肌中的FSR与在跖肌中的不同（<0.05）。
