Positive selection effects on the biochemical properties of mammal pyroglutamylated RFamide peptide receptor (QRFPR)

Abstract

Orphan receptor GPR103, a pyroglutamylated RFamide peptide receptor (QRFPR), is a class A G protein-coupled receptor (GPCR) and it is coupled to a Gi alpha subunit (Gi/0) and/or to a Gq protein. Synteny analysis revealed the existence of paralogous genes of QRFPR in mouse, zebrafish and coelacanth. These paralogous genes emerged along with speciesspecific gene or genome duplications that occurred during vertebrate evolution. 26RFa/QRFP is the high-affinity endogenous ligand for QRFPR and in fish it has been suggested as an orexigenic action of 26RFa/QRFP. The structure, tissuespecific expression and biochemical activity of the 26RFa/QRFP-QRFPR system are conserved across the Chordata phylum, from fish to mammals. In order to study the molecular evolution of mammal QRFPR, we searched for the presence of natural selection on the qrfpr genes using a bioinformatic approach. Overall, the results clearly indicate that mammal QRFPRs are under positive selection, but the majority of positively selected amino acids did not alter the biochemical properties of these proteins.

Copper/Zinc Superoxide Dismutase from the Crocodile Icefish Chionodraco hamatus: Antioxidant Defense at Constant Sub-Zero Temperature

“…However, it is also true that positive selection is one of the primary sources of evolutionary innovation and drives species adaptation in new environments [57]. In fact, many protein families, including those involved in immunity, reproduction, and cell signaling, were subjected to significant positive selection during their evolution [58][59][60].…”

Molecular Characterization, Protein–Protein Interaction Network, and Evolution of Four Glutathione Peroxidases from Tetrahymena thermophila

“…However, it is well known that positive selection is one of the primary sources of evolutionary innovation driving adaptation of species in new environments [ 35 ]. In fact, many protein families, including those involved in important cell functions, have undergone significant positive selection during their evolution [ 36 , 37 ]. Given that some isoforms, such as Tt-gpx11 and Tt-gpx12, represent members of the GPx family in which molecular evolution changed the ancestral structural features, it is possible to hypothesize that positive selection acted only on some portion of the protein, as suggested for some proteins of the human interactome [ 38 ].…”

Molecular Characterization, Protein-protein Interaction Network, and Evolution of four Glutathione Peroxidases from <em>Tetrahymena Thermophila</em>

“…However, it is well known that positive selection is one of the primary sources of evolutionary innovation driving adaptation of species in new environments [44]. In fact, many protein families, including those involved in important cell functions, have undergone significant positive selection during their evolution [45,46]. What does not emerge from protein-protein interaction network analysis is the correlation between GPxs and peroxiredoxins.…”