Tissue expression and predicted protein structures of the bovine ANGPTL3 and association of novel SNPs with growth and meat quality traits.

ABSTRACT

Angiopoietin-like protein 3 (ANGPTL3) is a secreted protein that regulates lipid, glucose and energy metabolism. This study was conducted to better understand the effect of ANGPTL3 on important economic traits in cattle. First, transcript profiles for ANGPTL3 were measured in nine different Jiaxian cattle tissues. Second, polymorphisms were identified in the complete coding region and promoter region of the bovine ANGPTL3 gene in 707 cattle samples. Finally, an association study was carried out utilizing these single nucleotide polymorphisms (SNPs) to determine the effect of these SNPs on the growth and meat quality traits. Quantitative real-time PCR analysis showed that ANGPTL3 was mainly expressed in the liver. The promoter of the bovine ANGPTL3 contained several putative transcription factor binding sites (SF1, HNF-1, LXRα, NFκß, HNF-3 and C/EBP). In total, four SNPs of the bovine ANGPTL3 gene were identified by direct sequencing. SNP1 (rs469906272 g.-38T>C) was identified in the promoter, SNP2 (rs451104723g.104A>T) and SNP3 (rs482516226 g.509A>G) were identified in exon 1, and SNP4 (rs477165942 g.8661T>C) was identified in exon 6. Changes in predicted protein structures due to non-synonymous SNPs were analyzed. Haplotype frequencies and linkage disequilibrium were also investigated. Analysis of four SNPs in cattle from different native Chinese breeds (Nanyang (NY) and Jiaxian (JX)) and commercial breeds (Angus (AG), Hereford (HF), Limousin (LM), Luxi (LX), Simmental (ST) and Jinnan (JN)) revealed a significant association with growth traits (including BW and hipbone width) and meat quality traits (including Warner-Bratzler shear force and ribeye area). Therefore, implementation of these four mutations in selection indices in the beef industry may be beneficial in selecting individuals with superior growth and meat quality traits.