Structure and Polymorphism Analysis of Transforming Growth Factor Beta Receptor 1 (TGFBR1) in Pigs

Abstract

Many quantitative trait loci (QTL) for growth and reproductive traits have been detected on the porcine chromosome region 1qter (SSC1qter), making it one of the most important genomic regions for pig breeding. SSC1q corresponds to human chromosome 9, on which lies transforming growth factor beta receptor 1 (TGFBR1). We cloned the porcine TGFBR1 cDNA and gene (as a candidate for QTL) and analyzed the gene structure and polymorphism. Porcine TGFBR1 consists of 9 exons and 8 introns. Intron 2 is alternatively spliced at the acceptor site, resulting in two kinds of mRNA, with putative open reading frames of 1500 and 1512 bp in length. The shorter one encodes 499 amino acid residues. The amino acid sequence has 96.2 and 97.2% sequence similarity to those of human and bovine TGFBR1, respectively. The sequence similarity between porcine and murine TGFBR1 is 95.6%. We detected three single-nucleotide substitutions in exons 1, 2, and 7. Those in exons 1 and 7 are nonsynonymous substitutions resulting in Pro8Ser and Ile413Val substitutions, respectively.

Isolation and molecular characterization of the porcine transforming growth factor beta type I receptor (TGFBR1) gene

“…A single splice variant involving the removal of the first 12 nucleotides of exon 3 has also been reported (Shimanuki et al, 2005). We have confirmed the (Thanaraj et al, 2004).…”

“…Most polymorphisms were detected in Berkshire and Meishan pigs as 79 out of these 85 nucleotide variations possess different alleles between them. Nonsynonymous SNPs at positions 84 and 57,615 lead to amino acid substitutions (Pro 8 -Ser 8 and Val 417 -Ile 417 ) which were also identified recently in pig (Shimanuki et al, 2005). The nucleotide variations were mostly found in the intronic regions.…”

“…The porcine TGFBR1 cDNA contains a complete ORF of 1512 bp encoding a predicted protein of 503 amino acids (Shimanuki et al, 2005). A single splice variant involving the removal of the first 12 nucleotides of exon 3 has also been reported (Shimanuki et al, 2005).…”

“…Recently, porcine TGFBR1 was mapped between microsatellite markers SW803 and SW705 on SSC1 using linkage and RH mapping (Kopecny et al, 2004), and the cDNA sequence was reported (Shimanuki et al, 2005). As TGFBR1 is located within a quantitative trait loci (QTL)-rich region on SSC1 for a variety of economically important traits (Hu et al, 2005), and its role in various developmental aspects in humans (Loeys et al, 2005); this suggests its potential role as a candidate gene for growth and development traits.…”

Molecular Characterization of TGF-β Type I Receptor Gene (Tgfbr1) in Chlamys farreri, and the Association of Allelic Variants with Growth Traits

“…As the major type I receptor for TGF-β ligands, such as TGF-β1, TGF-β2, TGF-β3, and GDF8 (myostatin) in mammals [11], [12], the TGF-β type I receptor (Tgfbr1) has been of great interest to researchers, and associations between Tgfbr1 allelic variations and gene expression or diseases have been explored in humans, revealing several causative loci [13]–[16]. Porcine Tgfbr1 has been studied extensively, as it falls within a quantitative trait locus (QTL)-rich region to which many growth and reproductive traits have been mapped [17]–[19], and single nucleotide polymorphisms (SNPs) significantly associated with porcine growth rates, including average daily gains during several growing stages, and reproductive traits, including gestation length and number of corpora lutea, were found in porcine Tgfbr1 , making this gene more valuable in livestock breeding [20].…”