Genome-Wide Selection Signals of the Min Pig Indicate That Genes Related to Fat and Energy Metabolism Play a Crucial Role in Responding to Cold Stress

As a typical northeast indigenous pig breed of China, the Min Pig (MZ) with excellent cold adaptability by long-term natural selection. This provides a natural animal model for understanding the genetic basis of cold exposure adaptation in pigs. In this study, a genome-wide selective sweep analysis (GWSA) of 30 MZ and 42 public pig genomes without cold resistant adaptability was performed to identify candidate genes (CDGs) of cold stress tolerance, based on genome-wide SNP dataset. The results revealed that a total 226 interacting CDGs were obtained from 5% windows of FST (≥ 0.412596), θπ ratio (≥ 2.125852484) and XP-CLR (≥ 22.08201682). 68 of them were enriched in 183 KEGG pathways, with 24 KEGG pathways significantly enriched (corrected-P < 0.05), including the cGMP-PKG and PI3K-Akt signaling pathway, etc. Specifically, numerous CDGs (e.g., AKT3, PRKG1, CREB3L3, ACSF3, and NDUFS7) were enriched in pathways related to fat synthesis and energy metabolism, such as Fatty acid biosynthesis, Carbohydrate digestion and absorption, Adipocytokine signaling pathway, Regulation of lipolysis in adipocytes and Insulin resistance, etc. In summary, this study not only identified relative CDGs underlying the adaptive genetic basis of cold stress resistance in MZ, but also provided a scientific foundation for the molecular breeding of environmental adaptability in pig.