lncING2-DT suppresses proliferation and promotes differentiation of porcine skeletal muscle satellite cells through an ING2-dependent mechanism

Heat stress (HS) severely impairs skeletal muscle development, yet the regulatory roles of long non-coding RNAs (lncRNAs) in this process remain largely unclear. In this study, RNA-seq was performed on porcine soleus (SOL), gastrocnemius (GAS), and tibialis anterior (TA) muscles under HS and control conditions, revealing multiple differentially expressed lncRNAs. Among them, ENSSSCG00000048143 (which we named lncING2-DT) was consistently down-regulated in all three muscle types of the HS treatment group compared with the control group, and was selected for further investigation. Functional analyses in porcine skeletal muscle satellite cells (PSCs) showed that lncING2-DT inhibited cell proliferation while promoting myogenic differentiation under normal conditions. Mechanistically, lncING2-DT positively regulated the expression and promoter activity of its neighboring gene ING2, and co-transfection experiments demonstrated that the inhibitory effect of lncING2-DT on PSC proliferation was partially dependent on ING2. RNA pull-down and mass spectrometry (MS) identified multiple lncING2-DT–interacting proteins, among which HNRNPU was identified as a candidate interacting protein that may participate in lncING2-DT-mediated regulation of ING2. Under HS conditions, lncING2-DT expression was markedly reduced, accompanied by impaired myogenic differentiation, enhanced proliferation, apoptosis, and inflammatory responses. Notably, overexpression of lncING2-DT alleviated HS-induced cellular dysfunction by promoting differentiation, enhancing heat shock responses, and suppressing excessive apoptosis and inflammation. Collectively, these findings identify lncING2-DT as a critical regulator of PSC homeostasis and stress adaptation, providing novel insights into the molecular mechanisms underlying HS-induced skeletal muscle dysfunction.