Improvement in fertility is possible through gene assisted selection. Cattle fertility and genes underlying it should be thoroughly studied and exploited to find solution to declining cattle fertility. Reprimo (RPRM) gene is a pleiotropic gene involved in suppression of cancer, regulation of mitotic cell cycle, cell cycle arrest and regulation of survival. Comparison of protein tertiary structures is important in inferring functional characteristics of new proteins. This study used computational approach to identify some fertility functions of bovine RPRM gene using motif prediction and protein structure comparison. Amino acid sequences of bovine RPRM gene and some other cattle fertility genes were retrieved from GenBank. Motifs in the amino acid sequence of bovine RPRM gene were predicted using PROSITE software. The domain structure of bovine RPRM protein was predicted using simple modular architecture research tool (SMART). Protein tertiary structures (3D structures) of bovine RPRM gene and other cattle fertility genes were predicted with Phyre 2 software. To have structural and functional similarity, it has been found that protein structure after superimposition should have Root Mean Square Deviation (RMSD) value less than or equal to 2A. The protein 3D structures of other cattle fertility genes were superposed against the protein 3D structure of bovine RPRM gene using SuperPose web server and the proteins with RMSD value of 2A or less were predicted as proteins with similar functions and structures as bovine RPRM gene. The predicted motifs (N-glycosylation site, N-myristoylation site, and cAMP and cGMP-dependent protein kinase phosphorylation site) and protein structure comparison revealed that, bovine RPRM gene and bovine growth hormone gene have the same fertility function with alpha carbon and backbone root mean square deviations of 1.94 A and 1.81 A, respectively. It follows therefore that other fertility functions of bovine RPRM gene included sexual maturation, steroidogenesis, gametogenesis, gonadal differentiation and gonadotrophin secretion which are the functions of growth hormone gene. Keywords : Reprimo gene, fertility, growth hormone gene, motifs, root mean square deviation
