Abstract: Na+, Cl-, and K+ ion concentrations and sodium potassium ATPase activity were determined in the coelomic fluid of sea cucumber Apostichopusjaponicus with body mass of(16.38±1.27)g exposed to a salinity of 18 in 0, 6, 24 and 48 h.The results indicated that the sodium ion concentration increased significantly at 6 h after salinity stress(P<0.05), and then decreased with the stages of stress time.The lower concentrations of chloride and potassium ions were presented in the sea cucumber exposed to salinity stress than those of the control group(P<0.05), with the minimum at 6 h.The activity of sodium-potassium ATPase was lower than that of the control group at 6 h, with the minimum at 24 h.That miR-2011, miR-124 and miR-2010 formed a stable stem-loop structure based on the precursor sequences and mature sequences, which indicated that the three miRNAs were relatively conservative.Three differential expression in miRNAs(miR-2011, miR-2010 and miR-124)were presented and interacting target genes were obtained through miRNAs and target genes binding sites.Quantitative expression profiles showed that the miR-2011, miR-2010 and miR-124 were up-regulated in the sea cucumber exposed to salinity stress, compared to the maximal expression levels of miR-2011 and miR-2010 presented in 48 h under low-salt stress, 80 times and 24 times compared to control group(0 h), respectively.The target genes of miR-2011 were PPM1L and PBK, the miR-2010 to PPM1L, and the miR-124 to EGF3 and IMPA1.The findings indicate that the three miRNAs related to salinity genes are conservative and involved in regulation of salinity stress in sea cucumber.
2022, Vol. 37 
