Fatty acid transport protein 1 (FATP1), an integral membrane protein that facilitates long-chain fatty acid influx, is involved in the genetic network for oleic acid synthesis. The aim of this study was to examine the association of FATP1 polymorphisms with live animal meat quality traits in Chinese Qinchuan cattle. Quantitative real-time PCR analysis demonstrated that FATP1 has a broad tissue distribution in Qinchuan cattle and is highly expressed in longissimus dorsi muscle and back fat. Using direct DNA sequencing of the FATP1 gene in 458 Qinchuan cattle, four single nucleotide polymorphisms (SNPs; g.28265 G>C, g.28381 G>A, g.28470 T>C, and g.28672 G>A) were identified for genotyping within a 671-bp region, including exon 3, intron 3, exon 4, intron 4, and part of exon 5 of the FATP1 gene. Positive effects of genotypes CC (g.28470 T>C locus) and AA (g.28672 G>A locus) on meat quality traits were obtained by association analysis. These results indicate the associations of g.28470 T>C and g.28672 G>A with meat quality traits in Qinchuan cattle. Thus, the FATP1 gene may be used in marker-assisted selection of beef cattle in breeding programs.

Fatty acid binding protein 4 (FABP4) is a member of the FABP family of proteins that bind fatty acids and play important roles in fatty acid uptake and intracellular transport. In the present study, we cloned the 5'-regulatory region of bovine and identified its transcription initiation sites. Sequence comparative analysis demonstrated amino acids and promoter sequences of were highly conservative in mammals. Real-time PCR analysis revealed the products of bovine were very highly expressed in subcutaneous adipose tissue. Serial deletion constructs of the bovine 5'-regulatory region evaluated in a dual-luciferase reporter assay showed that 209 bp upstream from the transcription initiation site was its core promoter. An electrophoretic mobility shift assay combined with a site-directed mutation experiment indicated that peroxisome proliferator activated receptor gamma (PPARγ), CCAAT/enhancer-binding protein β (C/EBPβ), and sterol regulatory element-binding protein (SREBP) were important transcription factors for bovine . These results provide an important basis for further understanding the regulation of bovine .

Keratin-associated proteins 8.1 gene (KAP8.1) is a structural gene responsible for the cashmere. KAP8.1 protein contains high glycine and tyrosine, which concerns regulation and function of the matrix structure fiber. In this study, the polymorphism of KAP8.1 gene was detected by methods of aPCR-SSCP (asymmetric polymerase chain reaction single-strand conformation polymorphism) and DNA sequencing in 791 individuals from two breeds. The results showed that there were two mutations in this gene. The mutations were described as c.63 T>G and c.66 C>G, which would result in two synonymous mutations in KAP8.1 protein. The findings go against previous research, in which there was not polymorphism at KAP8.1 gene. The reasons might be that different cashmere breeds were detected in two studies. Further analysis of results leads us to believe that the polymorphism of KAP8.1 gene might be relevant to fiber diameter.

Visfatin is a protein that is preferentially produced in visceral adipose tissue. Both its tissue expression and secreted plasma levels increase in parallel with obesity. Therefore, the present study is focused on detecting insertion in bovine visfatin gene and analyzing its effect on growth traits in four Chinese cattle breeds (Nangyang, Qinchuan, Jiaxian, and Chinese Holstein) using PCR-SSCP, DNA sequencing and agarose electrophoresis methods. For the first time, a 35-bp insertion was described in the gene and two alleles were revealed: W and I. The x (2)-test analysis demonstrated that all breeds were in agreement with Hardy-Weinberg equilibrium (P > 0.05). The associations of the novel 35 bp-insertion of visfatin gene with growth traits of Nanyang cattle at 6, 12, 18, and 24 months old were analyzed: 6 month-old cows with genotype WW had greater birth weight than cows with genotype II and WI (P < 0.01 or P < 0.05). These results suggest that the presence of 35 bpinsertion in visfatin gene may influence the birth weight and bodyweight in 6 month-old cows.

The keratins and keratin-associated proteins (KAPs) are a large heterogeneous group of proteins that make up about 90% of the cashmere fiber. Keratin-associated proteins 9.2 gene (KAP9.2) is one of the ultra high sulfur KAPs, which might play an important role in the bundling of intermediate filaments. In this study, the deletion/insertion mutation of KAP9.2 gene in 997 cashmere goat samples was firstly detected, at the same time, parts of these samples were sequenced. The results showed that two alleles were detected at this KAP9.2P1 locus, named allele W and D. The frequencies of the KAP9.2-W allele in Inner Mongolia White cashmere (n=785) and Shaanbei White cashmere goat breeds (n=212) were 0.878 and 0.790, respectively. The χ2-test showed that the genotype distributions in these two cashmere goat breeds were not in agreement with Hardy–Weinberg equilibrium. According to the classification of polymorphism information content (PIC), Shaanbei White cashmere goat was more polymorphic at this locus. Moreover a 30bp-deletion mutation was described at KAP9.2P2 locus for the first time and no deletion/insertion was described at KAP9.2P1 locus. The results possibly revealed that the size polymorphism existed in the two Chinese cashmere goat and the 30bp-deletion mutation was possibly caused by variations in the number of the decapeptide repeat structures.