Expression of Genes Regulating Muscle Growth in Pink Salmon Oncorhynchus gorbuscha (Walb.) Smolts from Different Rivers of the White and Barents Sea Basins

The expression of genes encoding myogenic regulatory factors—Myf5, MyoG, MyoD1a, MyoD1b, heavy (MyHC) and light (mlc2) myosin chains, as well as myostatin (Mstn1a)—was studied in pink salmon Oncorhynchus gorbuscha (Walb.) smolts caught in rivers during the period of migration for fattening to the White and Barents seas. It was found that individuals from the Keret River had higher expression levels of the mlc2, MyHC, MyoD1a, MyoD1b, and MyoG genes compared to those in the Varzuga River. It was shown that the smolts from the rivers of the White Sea basin - the Indera, Keret, and Umba, had higher expression values of the MyoD1b and MyoG genes, and in the Varzuga River, expression of Myf5 was higher, in contrast to fish from the Voronya River of the Barents Sea basin. The highest level of expression of the Mstn1a gene was detected in pink salmon in the Voronya River. The obtained results indicate differences in the regulation of myogenesis in pink salmon smolts depending on the temperature and feeding conditions of the habitat in different rivers.