scholarly journals Tissue Expression and Variation of the DGAT2 Gene and Its Effect on Carcass and Meat Quality Traits in Yak

Animals ◽  
2019 ◽  
Vol 9 (2) ◽  
pp. 61 ◽  
Author(s):  
Jiang Hu ◽  
Bingang Shi ◽  
Jianpeng Xie ◽  
Huitong Zhou ◽  
Jiqing Wang ◽  
...  

Diacylglycerol acyltransferase-2 (DGAT2) plays a key role in the synthesis of animal triglycerides (TGs). This study investigated the relative expression of the DGAT2 gene in tissues, variation in the gene, and its association with carcass and meat quality traits in yaks (Bos grunniens). DGAT2 was found to be expressed in twelve tissues investigated, but the highest expression was detected in subcutaneous fat, and moderate levels were observed in the liver, heart, longissimus dorsi muscle, and abomasum. Three variants (A1 to C1) were found in intron 5 and another three variants (A2 to C2) were found in intron 6, with two single-nucleotide polymorphisms (SNPs) being identified in each region in 694 Gannan yaks. Variants B1 and C2 were associated with a decrease in Warner–Bratzler shear force (WBSF) (p = 0.0020 and p = 0.0441, respectively), and variant C1 was associated with an increase in WBSF (p = 0.0434) and a decrease in drip loss rate (p = 0.0271), whereas variant B2 was associated with a decrease in cooking loss rate (p = 0.0142). Haplotypes A1-A2 and B1-A2 were found to be, respectively, associated with an increase and a decrease in WBSF (p = 0.0191 and p = 0.0010, respectively). These results indicate that DGAT2 could be a useful gene marker for improving meat tenderness in yaks.

2018 ◽  
Vol 61 (4) ◽  
pp. 433-439
Author(s):  
Xiaomei Sun ◽  
Xiuxiang Wu ◽  
Yongliang Fan ◽  
Yongjiang Mao ◽  
Dejun Ji ◽  
...  

Abstract. Considerable evidence has demonstrated that the μ-calpain (CAPN1) gene and its inhibitor calpastatin (CAST) gene are major factors affecting meat quality. Marker-assisted selection (MAS) has been widely used to improve beef quality traits. Therefore, the objective of the present study was to investigate the single nucleotide polymorphisms (SNPs) of bovine CAPN1 and CAST genes using 367 animals representing the four main Chinese cattle breeds and to explore the effects of these SNPs on meat quality traits. Two SNPs within CAPN1 and one SNP in CAST were successfully identified in cattle. Genetic diversity analyses suggested that most SNPs in the four breeds exhibited a moderate genetic diversity. Moreover, associations between individual markers and meat quality traits were analyzed in Chinese Simmental cattle. The CAPN1 4558 A > G locus was found to be significantly associated with shear force value (SFV) and marbling score (BMS), and CAPN1 4684 C > T exerted a significant effect on SFV, while the CAST genotype was not significantly associated with any of the measured traits. SFV, commonly used to measure meat tenderness, represents an important quality trait as it contributes to the flavor of cooked meat. This work confirms the effect of CAPN1 on beef tenderness and lays an important foundation for future cattle breeding.


2019 ◽  
Author(s):  
Joel David Leal Gutierrez ◽  
Mauricio A. Elzo ◽  
Raluca G. Mateescu

Abstract Background: Transcription has a substantial genetic control and genetic dissection of gene expression could help us understand the genetic architecture of complex phenotypes such as meat quality in cattle. The objectives of the present research were: 1) to perform eQTL and sQTL mapping analyses for meat quality traits in longissimus dorsi muscle; 2) to uncover genes whose expression is influenced by local or distant genetic variation; 3) to identify expression and splicing hot spots; and 4) to uncover genomic regions affecting the expression of multiple genes. Results: Eighty steers were selected for phenotyping, genotyping and RNA-seq evaluation. A panel of traits related to meat quality was recorded in longissimus dorsi muscle. Information on 112,042 SNPs and expression data on 8,588 autosomal genes and 87,770 exons from 8,467 genes were included in an expression and splicing quantitative trait loci (QTL) mapping (eQTL and sQTL, respectively). A gene, exon and isoform differential expression analysis previously carried out in this population identified 1,352 genes, referred to as DEG, as explaining part of the variability associated with meat quality traits. The eQTL and sQTL mapping was performed using a linear regression model in the R package Matrix eQTL. Genotype and year of birth were included as fixed effects, and population structure was accounted for by including as a covariate the first PC from a PCA analysis on genotypic data. The identified QTLs were classified as cis or trans using 1 Mb as the maximum distance between the associated SNP and the gene being analyzed. A total of 8,377 eQTLs were identified, including 75.6% trans, 10.4% cis, 12.5% DEG trans and 1.5% DEG cis; while 11,929 sQTLs were uncovered: 66.1% trans, 16.9% DEG trans, 14% cis and 3% DEG cis. Twenty-seven expression master regulators and 13 splicing master regulators were identified and were classified as membrane-associated or cytoskeletal proteins, transcription factors or DNA methylases. These genes could control the expression of other genes through cell signaling or by a direct transcriptional activation/repression mechanism. Conclusion: In the present analysis, we show that eQTL and sQTL mapping makes possible positional identification of gene and isoform expression regulators.


2018 ◽  
Vol 27 (4) ◽  
Author(s):  
Terhi Iso-Touru ◽  
Maiju Pesonen ◽  
Daniel Fischer ◽  
Arto Huuskonen ◽  
Anu Sironen

High meat quality and specifically meat tenderness are desired traits by the consumers, however the environmental impact of meat production is becoming a relevant factor in the industry. Therefore, breeding of dual purpose cattle breeds may answer the high demand of meat production in the future. In this study we identified statistical differences between genotypes of CAST and CAPN1 gene variants with meat quality traits in a dairy breed (Nordic Red Cattle) and compared the results with beef breed (Aberdeen Angus). Our results show that the favorable alleles have not been selected in the studied dairy breed and thus could be used as a tool for improvement of meat quality. The genes were associated with specific meat quality traits (i.e. sensory juiciness, marbling score and meat color) also in the dairy breed. This supports the utility of known meat quality associated genetic variants to improve meat quality in dairy breeds.


2018 ◽  
Vol 58 (7) ◽  
pp. 1358 ◽  
Author(s):  
Javier Ithurralde ◽  
Gianni Bianchi ◽  
Oscar Feed ◽  
Fernando Nan ◽  
Fernando Ballesteros ◽  
...  

The aims of the present study were to describe intermuscular differences in meat-quality traits in 15 young-sheep muscles, and to study the associations between meat quality and fibre typing across all (pooled) muscles as well as in previously selected homogeneous contractile–metabolic groups of muscles (slow-oxidative, intermediate and fast-glycolytic muscles). Meat-quality traits (pH, colour, expressed juice, cooking losses, tenderness and sarcomere length) and fibre typing were evaluated after 24 h of slaughter in 15 muscles from five cross-bred young sheep. Across all the studied muscles, intermuscular differences in some meat-quality traits (pH24, a* and expressed juice) seemed to be mainly explained by muscle oxidative activity, while intermuscular variation in other meat-quality traits (L*, b* and Warner–Bratzler shear force) were mainly explained by differences in fibre sizes. Within fast-glycolytic muscles, larger fast-glycolytic fibres and reduced oxidative activity were generally associated with lower ultimate pH, higher L* values, lower a* values and longer sarcomeres. Within intermediate muscles, larger fast-glycolytic fibres and reduced oxidative activity were generally associated with lower ultimate pH, higher L* values, shorter sarcomeres and reduced meat tenderness. Within slow-oxidative muscles, larger fast-glycolytic fibres and reduced oxidative activity were generally associated with lower amounts of expressed juice, lower a* values and reduced meat tenderness. The present study has contributed to a better understanding of the influence of muscle fibre types on intermuscular meat-quality variation, suggesting that although muscle fibre diversity may explain, at least in part, intermuscular differences in meat quality, these associations can also slightly vary among muscle contractile–metabolic groups.


2013 ◽  
Vol 45 (21) ◽  
pp. 1012-1020 ◽  
Author(s):  
P. C. Tizioto ◽  
J. E. Decker ◽  
J. F. Taylor ◽  
R. D. Schnabel ◽  
M. A. Mudadu ◽  
...  

Meat quality traits are economically important because they affect consumers' acceptance, which, in turn, influences the demand for beef. However, selection to improve meat quality is limited by the small numbers of animals on which meat tenderness can be evaluated due to the cost of performing shear force analysis and the resultant damage to the carcass. Genome wide-association studies for Warner-Bratzler shear force measured at different times of meat aging, backfat thickness, ribeye muscle area, scanning parameters [lightness, redness (a*), and yellowness] to ascertain color characteristics of meat and fat, water-holding capacity, cooking loss (CL), and muscle pH were conducted using genotype data from the Illumina BovineHD BeadChip array to identify quantitative trait loci (QTL) in all phenotyped Nelore cattle. Phenotype count for these animals ranged from 430 to 536 across traits. Meat quality traits in Nelore are controlled by numerous QTL of small effect, except for a small number of large-effect QTL identified for a*fat, CL, and pH. Genomic regions harboring these QTL and the pathways in which the genes from these regions act appear to differ from those identified in taurine cattle for meat quality traits. These results will guide future QTL mapping studies and the development of models for the prediction of genetic merit to implement genomic selection for meat quality in Nelore cattle.


2014 ◽  
Vol 54 (4) ◽  
pp. 414 ◽  
Author(s):  
Y. H. B. Kim ◽  
M. Kerr ◽  
G. Geesink ◽  
R. D. Warner

This study evaluated effects of high pre-rigor temperature and duration and suspension of lamb sides on quality traits and protein denaturation in two muscles [semimembranosus (SM) and longissimus thoracis et lumborum (LTL)]. Twenty-four lamb carcasses, within each of 3 slaughter days, were used to assign eight carcasses to one of four pre-rigor temperature treatments: chilled at 2°C directly after slaughter, or held at 37°C in water for 1.5, 3.0 or 4.5 h before transfer to a 2°C chiller. At ~15 min post slaughter, one side of each carcass was suspended from the Achilles tendon, whereas the other side was suspended by the aitch bone and the leg tied down to the ribs. The sides subjected to aitch bone hanging had an increased sarcomere length in the SM, but decreased sarcomere length in the LTL. For the LTL, the time of exposure to high pre-rigor temperature had a significant effect on measures of protein denaturation and related meat quality traits such as purge and colour, although tenderness (shear force) after 2 days of aging was not affected. For the SM, the high temperature treatment also resulted in increase in measures of protein denaturation and thus negatively influenced meat quality traits such as purge, colour and shear force after aging. However, these effects on purge and shear force in the SM were significantly mitigated by the aitchbone hanging treatment. The results of the present experiment indicate that pre-rigor aitchbone hanging of muscles can counteract the negative effects of high pre-rigor temperature on both water loss and meat tenderness.


Sign in / Sign up

Export Citation Format

Share Document