Abstract The expression of some structural and regulatory muscle protein genes as well as the activity of the main intracellular proteases (calpains, proteasomes) in caged rainbow trout in the periods favorable for growth and under hyperthermia were estimated. Intense growth of fish was accompanied by high transcriptional activity of the myosin heavy chain ( MyHC ) gene with the constraining influence of myostatin, high protein turnover rate, and stable levels of myogenic factors, MyoG and MyoD1b . Trout growth retardation in response to summer increase in water temperature was associated with a decrease in gene expression of the main protein of myofibrils, myosin. In hyperthermia, proteolytic activity of calpains and proteasomes, which determine the level of protein degradation in muscle and thereby regulate the intensity of protein accumulation and overall growth, also decreased. Thus, changes in the intensity of myofibrillar protein synthesis, myogenesis, and protein degradation in rainbow trout during periods favorable for growth and under hyperthermia occur in a coordinated manner indicating a relationship of these processes.

中文翻译：

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热疗对养殖虹鳟鱼骨骼肌蛋白酶和生长调节剂的影响

摘要 估计了在有利于生长和高温条件下的网箱虹鳟鱼中一些结构和调节肌肉蛋白基因的表达以及主要细胞内蛋白酶（钙蛋白酶、蛋白酶体）的活性。鱼的强烈生长伴随着肌球蛋白重链 (MyHC) 基因的高转录活性，受肌生长抑制素的限制性影响，蛋白质周转率高，生肌因子 MyoG 和 MyoD1b 水平稳定。夏季水温升高导致鳟鱼生长迟缓与肌原纤维主要蛋白质肌球蛋白基因表达的降低有关。在热疗中，钙蛋白酶和蛋白酶体的蛋白水解活性，这决定了肌肉中蛋白质降解的水平，从而调节蛋白质积累和整体生长的强度，也降低了。因此，虹鳟鱼的肌原纤维蛋白合成、肌生成和蛋白质降解强度在有利于生长和高温下发生的变化以协调的方式发生，表明这些过程之间存在关系。