Lnc PLAAT3 -AS Regulates PLAAT3 -Mediated Adipocyte Differentiation and Lipogenesis in Pigs through miR-503-5p.

Animal fat deposition has a significant impact on meat flavor and texture. However, the molecular mechanisms of fat deposition are not well understood. Lnc PLAAT3 -AS is a naturally occurring transcript that is abundant in porcine adipose tissue. Here, we focus on the regulatory role of lnc PLAAT3 -AS in promoting preadipocyte proliferation and adipocyte differentiation. By overexpressing or repressing lnc PLAAT3 expression, we found that lnc PLAAT3 -AS promoted the transcription of its host gene PLAAT3 , a regulator of adipocyte differentiation. In addition, we predicted the region of lnc PLAAT3 -AS that binds to miR-503-5p and showed by dual luciferase assay that lnc PLAAT3 -AS acts as a sponge to absorb miR-503-5p. Interestingly, miR-503-5p also targets and represses PLAAT3 expression and helps regulate porcine preadipocyte proliferation and differentiation. Taken together, these results show that lnc PLAAT3 -AS upregulates PLAAT3 expression by absorbing miR-503-5p, suggesting a potential regulatory mechanism based on competing endogenous RNAs. Finally, we explored lnc PLAAT3 -AS and PLAAT3 expression in adipose tissue and found that both molecules were expressed at significantly higher levels in fatty pig breeds compared to lean pig breeds. In summary, we identified the mechanism by which lnc PLAAT3 -AS regulates porcine preadipocyte proliferation and differentiation, contributing to our understanding of the molecular mechanisms of lipid deposition in pigs.