ead to a reduce in PPAR expression, thereby lessen fatty acid catabolism. The resulting raise within the fatty acid content material may induce PPAR expression and thereby result in enhanced expression of genes associated with fatty acid uptake (lipoprotein lipase and CD36) and increased fat deposition (Fig. 7) [68]. The mRNA enrichment evaluation between yaks and cattle revealed that GO terms associated with `protein targeting to peroxisome’ and `long-chain fatty acid metabolic process’ were also enriched. This obtaining led us to speculate that the mechanism of fat deposition by way of POR regulates PPAR, which permits yaks to resist the cold condition on the plateau. The core mRNAs in Venn diagrams portion B (represented the variations among yaks at unique altitude gradients) have been significant enriched in the maintenance of typical cellular biological functions. Solar radiation is definitely an important and inevitable component from the plateau atmosphere. Ultraviolet (UV) radiation damages numerous cellular elements, like DNA. UV-damaged DNA is repaired by light K-Ras Storage & Stability repair and dark repair (NER) [70, 71]. NER consists of two subpathways: worldwide genomic repair (GGR) recognizes UVFig. 7 POR influences the regulatory mechanism of fat metabolism by regulating PPARGe et al. BMC Genomics(2021) 22:Web page 11 ofdamage in DNA throughout the genome, and transcription-coupled repair (TCR) initiates the repair of transcribed strands. In mammals, UVSSA has been implicated in TCR. Loss-of-function alleles in UVSSA exhibit greater UV sensitivity [72]. The core gene UVSSA may play a vital part inside the lung tissue of yaks to assist the animals overcome UV radiation. The outcomes in the prior enrichment evaluation of circRNAs revealed the huge influence of UV radiation on yaks. The resistance of yaks to UV radiation is an significant a part of their adaptation around the MEK1 web Tibetan Plateau. Other core genes within the network obtained from the comparison of yaks at unique altitudes, like SAFB-like transcriptional modulator (SLTM) and PARP4, have been also associated with sustained life activities of cells. SLTM has well-described functions in transcriptional repression and RNA splicing, is ubiquitously expressed and plays significant roles in numerous cellular processes, like cell development, DNA repair, strain response, and apoptosis. PARP4 plays an active role in cellular recovery from DNA harm, improves genetic stability and reduces recombination. In contrast, PARP4 also tends to make cells insensitive to apoptotic stimuli [73]. Furthermore, the core mRNAs in component B involve CLCN7. The CLCN7 gene encodes the 803amino-acid protein chloride channel protein 7 (ClC7), which offers the chloride conductance required for effective proton pumping within the osteoclast ruffled membrane [74] and is involved in acidification with the resorption lacuna. Mutations within the CLCN7 gene lead to autosomal dominant osteoporosis.Supplementary InformationThe online version includes supplementary material readily available at doi. org/10.1186/s12864-021-08044-9. Added file 1. Fig. S1. Distribution of sampling location. T1 represented the yaks from Maqu County inside the Gannan Tibetan Autonomous Prefecture of Gansu Province at an altitude of 3400 m, T2 represented the yaks from Bange County, Linzhou County and Dangxiong County within the Tibetan Autonomous Area at an altitude of 4200 m, T3 represented the yaks from Anduo County in the Tibetan Autonomous Region at an altitude of 5000 m, and CON represented the Zaosheng cattle from Ningxian County in