Identification of Potential Roles of Bestrophin 3 in the Growth Performance of Ortiental River Prawn Macrobrachium nipponense by RNA Interference

Macrobrachium nipponense is an economically important freshwater prawn species in China, where larger individuals have higher commercial value than smaller ones. Previous studies indicated that bestrophin 3 (BEST3) may play a regulatory role in the growth performance of this species. Therefore, the present study investigated the potential functions of the BEST3 gene in the growth of M. nipponense by using quantitative real-time PCR (qPCR) and RNA interference (RNAi), and also searched for growth-related single-nucleotide polymorphisms (SNPs) within this gene. qPCR results revealed that Mn-BEST3 expression was widely detected across all tested tissues, suggesting that this gene may serve multiple functions in M. nipponense. Notably, its highest expression was observed in muscle tissue, which was significantly greater than that in all other tested tissues (p < 0.05), implicating a potential role for this gene in growth regulation. Further qPCR analysis confirmed that the synthesized dsBEST3 effectively reduced Mn-BEST3 expression. The body mass gain percentage in the dsBEST3-injected group was significantly lower than that in the dsGFP-injected control group, with differences becoming significant from Day 12 onward in both males and females (p < 0.05). These findings indicate that Mn-BEST3 plays a positive role in regulating growth in M. nipponense. Finally, three SNPs were identified in the coding region of this gene. The associations of these three SNPs with growth performance, including body weight and total length, were further validated using 50 male and 50 female prawns derived from a full-sib family at approximately 5 months post-hatching. Among them, one SNP (S31_23192836) was found to be associated with growth performance in both male prawns and female prawns. Overall, this study confirmed the positive regulatory role of BEST3 in the growth of M. nipponense and identified growth-related SNPs within this gene. These results improve our understanding of the molecular mechanisms underlying growth regulation and support the production of populations with superior growth traits through marker-assisted selection.