Novel human G-protein-coupled receptors

https://doi.org/10.1016/S0006-291X(03)00709-5Get rights and content

Abstract

G-protein-coupled receptors (GPCRs) are important mediators of signal transduction and targets for pharmacological therapeutics. Novel receptor–ligand systems have been discovered through the identification and analysis of orphan GPCRs (oGPCRs). Here we describe the discovery of seven novel human genes encoding oGPCRs. Each novel oGPCR gene was discovered using customized searches of the GenBank genomic databases with previously known GPCR-encoding sequences. The expressed genes can now be used in assays to determine endogenous and pharmacological ligands. GPR133, GPR134, GPR135, GPR136, and GPR137 share identities with a prostate-specific odorant-like GPCR-encoding gene (PSGR). GPR138 and GPR139 share identities with an odorant-like gene derived from human erythroid cells. Transcripts encoding GPR133, GPR134, GPR135, GPR136, and GPR137 were detected in various CNS tissues. The expression of odorant-like genes in non-olfactory tissues requires further clarification, which may be achieved through the search for endogenous cognate ligands for these and other oGPCRs.

Section snippets

Materials and methods

Database searching. We queried the non-redundant (nr) and high-throughput genomic sequences (HTGS) databases maintained by the National Center for Biotechnology Information (NCBI) with the amino acid sequences of various GPCRs using the TBLAST algorithm [8]. Returned genomic sequences having statistically significant scores were further examined. The conceptualized protein sequences encoded by these genomic sequences were used to query the nr database to determine whether these sequences

Cloning of GPCR-encoding genes

A customized search of the HTGS database retrieved five candidate GPCR-encoding sequences clustered within a bacterial artificial chromosome (BAC) clone localized to human chromosome 11 (GenBank Accession No. AC090719). Primers were designed and used to PCR amplify the five DNA sequences. The PCR amplified products were cloned into pcDNA3 and sequenced. These clones were named GPR133, GPR134, GPR135, GPR136, and GPR137, and they encoded proteins of 350, 324, 317, 318, and 325 amino acids in

Discussion

In this report, we have described the discovery of seven novel human oGPCRs. The receptor genes are divided into two groups. GPR133, GPR134, GPR135, GPR136, and GPR137 are closely related to each other, and their presence within the same human contig suggests a tight clustering of these genes. As a group, these receptor genes most closely resembled an orphan receptor (PSGR) which shows prostate-specific localization [11], [12], [13], as well as some expression in the olfactory zone and the

Acknowledgements

This work was supported by a grant from the Canadian Institutes of Health Research.

References (32)

Cited by (0)

View full text