2.7. Protein and Protein Interaction Network

In order to better understand the functional and regulatory roles of NR1D1 and NR4A2 in male yak reproductive hormone biosynthesis, the protein-protein interaction (PPI) networks were constructed using the STING v 10.0 the candidate proteins involved in sterol hormone biosynthesis [12], such as androgen receptor (AR), StAR and cytochrome P450, family 17 subfamily A, polypeptide 1 (CYP17A1) (detailed in Table S2) using STRING v 10.0 database (online, https://www.string-db.org/ accessed on 30 October 2021) [23] and Cytoscape 2.8.1 software [24]. Further Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genome (KEGG) network analyses were performed using Clue-go and Ingenuity pathway analysis (IPA) (Ingenuity Systems, www.ingenuity.com, accessed on 21 July 2021).