The Function of the Lysophospholipase 1 (LYPLA1) Gene in Fetal Sheep Myoblast Proliferation and Myogenic Differentiation.

Evidence from genome-wide association studies (GWAS) links genetic variants near the LYPLA1 locus to variations in sheep muscle development. To further investigate whether LYPLA1 expression plays a role in fetal sheep myoblast development, we performed gain-of-function/loss-of-function analyses targeting LYPLA1 using siRNA and recombinant vectors. CCK-8 assays, EdU staining, and flow cytometry were used to investigate the effects of both LYPLA1 knockdown and overexpression on the proliferation of fetal sheep myoblasts. Furthermore, this study investigated the effect of LYPLA1 on myogenic differentiation by means of indirect immunofluorescence staining with MyHC and quantitative analysis of myogenic regulatory factor (MRF) expression. The results showed that downregulation of LYPLA1 significantly reduced cell viability and proliferation rate, arrested myoblasts in the G2 phase, and inhibited proliferation. These effects were reversed when LYPLA1 was overexpressed. Furthermore, LYPLA1 knockdown significantly impaired myotube formation during terminal differentiation (days 5-7). This defect was correlated with a marked reduction in the expression of myogenic regulatory factors (MRFs). This effect was reversed when LYPLA1 was highly expressed. In summary, this study demonstrates that LYPLA1 promotes the proliferation and differentiation of fetal sheep myoblasts, establishing its potential as a target for the molecular breeding of sheep.