Nucleotide polymorphisms and the 5′‐UTR transcriptional analysis of the bovine growth hormone secretagogue receptor 1a (GHSR1a) gene

Abstract

Growth hormone secretagogue receptor 1a (GHSR1a) mediates the different actions of its endogenous ligand, ghrelin. Ghrelin-GHSR is involved in many important functions that include growth hormone secretion and food intake. We evaluated the haplotype variety and characterized the microsatellite ((TG)(n) , 5'-UTR) and nucleotide polymorphisms of the bovine GHSR1a gene. The nucleotide sequencing of this gene (∼6 kb) revealed 47 single nucleotide polymorphisms (SNPs), four indels and the microsatellite ((GTTT)(n) , Intron 1). The 19 haplotypes were constructed from all nucleotide viability patterns and were divided into three major groups. Four SNPs (L24V, nt456(G>A), D191N and nt667(C>T)) and DelR242 in Exon 1 and a haplotype block of approximately 2.2 kb (nt667(C>T) ∼ nt2884 (A>G)) were found in Bos taurus breeds. Breed differences in allele frequencies of the two microsatellites, nt-7(C>A), L24V, and DelR242 loci were found (P < 0.005). A DelR242 was found in the Japanese Shorthorn (frequency: ∼ 0.44), Japanese Brown, five European cattle breeds, the Philippine native cattle, but none detected in the Japanese Black or the Mishima island cattle. Additionally, 5'-rapid amplification of cDNA ends and RT-PCR analyses revealed that there were two different kinds of transcripts: spliced, without a microsatellite within 5'-UTR (GHSR1a); and non-spliced, with the microsatellite (GHSR1b).

Plasma ghrelin is positively associated with body fat, liver fat and milk fat content but not with feed intake of dairy cows after parturition

“…Several single nucleotide polymorphisms (SNPs) and two different alternative transcript variants (GHSR1a and GHSR1b) have been described for the bovine GHSR gene (Colinet et al 2009, Komatsu et al 2010. Primers for PCR amplification and re-sequencing of the GHSR gene were designed based on the reference mRNA sequence (NM_001143736.1) and genomic sequences (AM931584.1 and NW_003103817.1).…”

“…Whereas the receptor for desacyl ghrelin is not yet known, acyl ghrelin binds to GHSR1a (Komatsu et al 2010(Komatsu et al , 2012. SNPs in the GHSR gene were found to be associated with growth and carcass traits in cattle (Zhang et al 2009, Komatsu et al 2011) and with growth, eating behaviour and obesity in humans (Baessler et al 2005, Gueorguiev et al 2009).…”

Bovine-Specific Nucleotide Polymorphisms and mRNA Expression of the Growth Hormone Secretagogue Receptor 1a (GHSR1a) Gene and its Genetic Association with Growth and Carcass Traits

“…This allele was never found in Japanese Black cattle (Figure 1). The 3R allele is widely distributed in many cattle breeds and may be an older allele than the 4R allele [8]. The DelR242 locus and/or the 3R allele may have some significant effects on growth and feeding behavior in Japanese Shorthorn cattle.…”

“…However, there was no published report on nucleotide polymorphisms from the 5'-flanking region to the 3'-UTR nor on the transcriptional analysis of the 5'-UTR of the GHSR1a gene in cattle. Therefore, we revealed for the first time, novel nucleotide polymorphisms from the 5'-flanking region to the 3'UTR (~6 kb) and two different kinds of transcripts (spliced, without a microsatellite within 5'UTR (GHSR1a); and nonspliced, with the microsatellite (GHSR1b)) of the bovine GHSR1a gene ( Figure 1) [8]. The nucleotide sequencing of this gene (~6 kb) revealed 47 single nucleotide polymorphisms (SNPs), 4 indels and the two microsatellites ((TG)n) in 5'UTR and (GTTT ) n in Intron 1).…”

“…To find a species specific motif within the promoter region of the GHSR1a gene in cattle, we compared potential transcriptional regulatory sequences in approximately 2.6 kb of the 5'-flanking region the GHSR1a gene among cattle, humans and mice [8]. Six bovine specific motifs were identified as follows: (1) Apolipoprotein E_B1, (2) A-activator binding site (AABS), (3) S1 nuclease-hypersensitive site, (4) Nuclear protein factors and erythroid specific 1_CS1, (5) Nuclear protein factors I, and (6) Nuclear factor_E1.…”