Diacylglycerol O-acyltransferase 1 Gene Research Articles

Association of DGAT1 with goat milk and meat production traits

Genetic factors can influence the composition of milk fat and its genetic variation. The purpose of our work was to familiarize and study the structure, role, and influence of the DGAT1 (or diacylglycerol-O-acyltransferase 1) gene on goat milk production, its structure, and relationship with milk fat for further research in improving the goat selection system. The selection of goats, aimed at increasing the frequency of alleles with a positive effect on this trait, was initiated by geneticists. In general, identifying and evaluating genetic markers for milk performance traits are the initial and crucial steps for establishing a marker-assisted selection system (MAS). Thus, increasing productivity through genetic selection is a common goal for many animal breeding programs worldwide. The amount of milk, milk fat, and proteins are essential features of dairy farming. In cheese production, milk fatty acids perform a crucial technical function, as they are the main building blocks of milk fat, giving the cheese its unique taste and textural properties. Milk fatty acids are necessary for producing many dairy products, while intramuscular fat is associated with meat quality. Triacylglycerols (TAG) are the main components of intramuscular fat and milk fat. Therefore, understanding polymorphisms and genes related to fat synthesis is essential for animal husbandry. The identification of quantitative trait loci (QTL) and genes associated with milk production traits has been supported by various studies over the past decade. It was established that QTL genes on chromosomes 14, 15, and 9 are related to the properties of milk and meat production in goats. The presence of the diacylglycerol-O-acyltransferase 1 (DGAT1) gene in goat chromosomes 14, 15, and 9 has been reported. Having a key role in fat metabolism and TAG synthesis, DGAT1 genes have attracted considerable attention, especially in animal milk production. Several polymorphisms have been documented in DGAT1 in different animal species, including many cattle and small cattle, for their association with milk production traits. The critical role of the DGAT1 gene in milk fat metabolism makes it an exciting candidate for genetic variation in milk characteristics in dairy goats.

DGAT1 gene polymorphism and their association with fat deposition and carcass quality in Pasundan cattle of Indonesia

Abstract. Dudi D, Hilmia N, Khaerunnisa I, Mushawwir A. 2023. DGAT1 gene polymorphism and their association with fat deposition and carcass quality in Pasundan cattle of Indonesia. Biodiversitas 24: 4202-4208. The bovineAcyl-CoA: Diacylglycerol O-acyltransferase 1 (DGAT1) gene is crucial to milk and meat quality in cattle. The K232A DGAT1 mutation was broadly used as a milk and meat quality genetic marker. Pasundan cattle are Indonesian local cattle from West Java. These local cattle have adapted to the tropical environment, environmental factors are not obstructing their development. The DGAT1 gene polymorphism information and their contribution to fat deposition and carcass quality in Pasundan cattle is very limited. The objective of this study was to examine the genetic polymorphism of the K232A DGAT1 gene and its association with fat deposition and carcass quality in Pasundan cattle population. The gene polymorphisms were identified using PCR, and direct sequencing to discover a single nucleotide polymorphism (SNP). All sequencing results (ABI trace files) were analyzed in FinchTV, BioEdit, and Molecular Evolutionary Genetic Analysis (MEGA) 6.0. Genotyping was performed on 80 Pasundan cattle. In comparison, Ongole-Grade (n=5), Bali (n=2), Simmental (n=2), Limousin (n=2), Madura (n=2), and Pesisir (n=2) were also used in this study. Their association with fat deposition and carcass quality was evaluated on seven heads of AK genotype and 23 heads of KK genotype. According to the sequencing result, two SNPs were found at g.201G>A and g.202C>A, respectively. The K232A DGAT1 locus was polymorphic in Pasundan cattle population with the K and A allele frequencies of 0.956 and 0.044, respectively. In addition, DGAT1 gene polymorphisms are not associated with back fat thickness, longissimus dorsi area, rump area, and intramuscular fat.

Effects of propylene glycol used at different doses in Akkaraman lambs rations on metabolism-related parameters and liver gene and protein expression during different feeding periods.

This study aimed to investigate the metabolic effects of propylene glycol (PG) over 60, 90, and 120 days in lambs. Seventy-two weaned male lambs were allocated into three groups: control (Con), PG1.5 (1.5 mL/kg live weight0.75 ), and PG3 (3mL/kg live weight0.75 ). Blood samples were collected at the beginning and slaughter days. Biochemical parameters (glucose, triglycerides, ALT, AST, LDH, BUN, and insulin) and gene and protein levels of peroxisome proliferator activated receptor gamma (PPARγ), diacylglycerol o-acyltransferase 1 (DGAT1), carbohydrate responsive element binding protein (ChREBP), and sterol regulatory element binding transcription factor 1c (SREBP-1c) in the liver were determined. Glucose in PG1.5 was increased on Day 60, while significant differences were observed in biochemical parameters except for insulin on the 60, 90, and 120 days. Biochemical parameters such as ALT, AST, LDH, and BUN increased over time, while triglycerides decreased. DGAT1 gene and protein levels were lower, while SREBP-1c and PPARγ were higher in PG groups on Day 60. While SREBP-1c was lower in PG1.5, ChREBP was higher in PG3 on Day 90. PPARγ, DGAT1, and ChREBP were upregulated in PG3 on Day 120. Positive correlations were found between proteins. The long-term use of PG in lambs did not have detrimental effects on metabolism. The study provides valuable insights into the molecular mechanisms underlying the metabolic effects of PG in lambs, shedding light on its potential applications in lamb production.

An oncogenic JMJD6-DGAT1 axis tunes the epigenetic regulation of lipid droplet formation in clear cell renal cell carcinoma

Characterized by intracellular lipid droplet accumulation, clear cell renal cell carcinoma (ccRCC) is resistant to cytotoxic chemotherapy and is a lethal disease. Through an unbiased siRNA screen of 2-oxoglutarate (2-OG)-dependent enzymes, which play a critical role in tumorigenesis, we identified Jumonji domain-containing 6 (JMJD6) as an essential gene for ccRCC tumor development. The downregulation of JMJD6 abolished ccRCC colony formation invitro and inhibited orthotopic tumor growth invivo. Integrated ChIP-seq and RNA-seq analyses uncovered diacylglycerol O-acyltransferase 1 (DGAT1) as a critical JMJD6 effector. Mechanistically, JMJD6 interacted with RBM39 and co-occupied DGAT1 gene promoter with H3K4me3 to induce DGAT1 expression. JMJD6 silencing reduced DGAT1, leading to decreased lipid droplet formation and tumorigenesis. The pharmacological inhibition (or depletion) of DGAT1 inhibited lipid droplet formation invitro and ccRCC tumorigenesis invivo. Thus, the JMJD6-DGAT1 axis represents a potential new therapeutic target for ccRCC.

Exploring single nucleotide polymorphisms in GH, IGF-I, MC4R and DGAT1 genes as predictors for growth performance in dromedary camel using multiple linear regression analysis

Understanding the genetic factors influencing the growth traits of animal is very important for an accurate selection and genetic improvement of these quantitative traits. Therefore, the aim of this study was to identify polymorphisms in growth hormone (GH), insulin-like growth factor-I (IGF-I), melanocortin-4 receptor (MC4R) and diacylglycerol O-acyltransferase 1 (DGAT1) genes and their association with body weight and daily gain in dromedary camels. Blood samples were collected from seventy camels using vacutainer tube containing EDTA as an anticoagulant for DNA extraction. PCR-DNA sequencing approach was performed to investigate polymorphisms in fragments for 5’ UTR of GH (286-bp) and part of coding sequence (CDS) of IGF-I (462-bp), MC4R (512-bp), and DGAT1 (390-bp) genes. Results revealed that there were single nucleotide polymorphisms (SNPs) in the investigated genes between the enrolled camels except for IGF-I gene that elicited a monomorphic pattern. The identified SNPs allocated camels into different groups according to which animal harbored the explored SNPs. Using multiple linear regression analysis (MLR), identified SNPs had a significant effect on body weight and weight gain at different age stages. Determination coefficients (R2) value indicated that variability in the phenotypic measurements of growth performance might be correlated with the identified SNPs in growth related genes. The area under the ROC curves was higher in the case of DGAT (0.793-1.0), followed by GH (0.736-0.866) and then MCR (0.410-0.545). DGAT anticipates body weight and weight gain traits better than GH and MCR. As a pilot study, single nucleotide polymorphisms in the investigated genes could be used as proxy predictors and genetic markers that permit a marker assisted selection for growth traits in dromedary camels.

Milk fat as a source of bioactive compounds

Milk fat as a source of bioactive compounds

DGAT1 polymorphism in Egyptian Zaraibi goat breed and their association with milk yield and composition

BackgroundThe triacylglycerols in milk fat determine the physical and functional properties of dairy products rich in milk fat. Therefore, understanding the variability of genes related to fat synthesis is important for food production. We investigated the effect of diacylglycerol O-acyltransferase 1 (DGAT1) gene polymorphism on milk production parameters of the Zaraibi goat. Milk components were estimated by infrared spectroscopy. Moreover, Restriction Fragment Length Polymorphisms (RFLP) were used to detect genetic variants in DGAT1 genes. The amplified products were sequenced and aligned to the caprine reference sequence of this gene.ResultsTwo alleles (T and C) were identified in Zaraibi goats. The T allele resulted in one silent mutation while the C allele specified two-point mutations: one was located within a non-coding region (T703C) and the other (T713C) causing a Ile → Thr substitution in the deduced amino acid sequence. Moreover, the DGAT1 polymorphism significantly (p < 0.05) affected total solid content of milk, wherein harboring CC genotype had significantly higher amount of total solid than those with TC genotype. Milk contents and yields did not differ significantly between goats with CC and TC genotype.ConclusionThese results advance our understanding of the genetic architecture of Zaraibi milk composition and will help to improve the management and breeding program of the Egyptian dairy goat.Graphical

Exploring novel single nucleotide polymorphisms and haplotypes of the diacylglycerol O-acyltransferase 1 (DGAT1) gene and their effects on protein structure in Iranian buffalo.

Diacylglycerol O-acyltransferase 1 (DGAT1) plays a key role in the synthesis of triglycerides. Recent studies have shown that a transition mutation resulting in substitutions of guanine by adenine in the DGAT1 gene in cattle has considerable effects on milk yield and composition. Currently, there is no systematic research reporting on the utilization of this gene segment in Iranian buffalo (Bubalus bubalis). In this study, the genetic differentiation of three indigenous Iranian buffalo populations was investigated in the region spanning exon 3 to exon 17 of the DGAT1 gene. A total of 200 buffaloes were genotyped, all the samples were sequenced directly in both directions with forward and reverse sequencing primers. Sequence analysis showed novel SNPs compared to the reference GenBank sequence (DQ886485) at nucleotide positions g.6097A>G, g.7036C>T, g.7338G>A, g.7710C>T, g.8087C>T, g.8259G>A, g.8275G>A, g.8367C>T, and g.8426C>T. No polymorphisms were found within exon 8. Therefore, the K232A position was thought to be a conserved and fixed region for high milk fat content (K allele) in Bos indicus and all buffalo breeds. Comparison with Indian buffalo revealed three exonic SNPs, one of which was nonsynonymous. A unique 22bp insertion was observed in intron 10 of DGAT1. Linkage disequilibrium analysis allowed the identification of nine haplotypes among the sampled animals. To our knowledge, this is the first report of sequencing analysis of the DGAT1 gene in Iranian buffalo. Our results suggest that genetic diversity exists and could be useful in examining the association between the DGAT1 gene and milk production traits in buffalo.

Genetic polymorphisms of the OLR1 and DGAT1 genes associated with milk components in Holstein Friesian dairy cattle under an intensive management in Central Java

Oxidized Low Density Lipoprotein Receptor 1 (OLR1) gene serves to encode the binding vascular surface receptors and to degrade the oxidized low-density lipoprotein. In dairy cattle a nucleotide mutation at 3′UTR location of the OLR1 gene results in C allele of which related to higher milk fat content than A allele. Diacylglycerol O-acyltransferase 1 (DGAT1) gene has a K232A mutation of which K allele also associated with higher milk fat content against A allele. This study was aimed to study the association of variant genotypes of the OLR1 and DGAT1 genes on milk fat and other milk components in Holstein Friesian (HF) dairy cattle. The target of this research was to obtain genotypes of the OLR1 and DGAT1 gene affecting highly to milk fat content and other milk components in domestic HF cattle. Animals observed were Holstein Friesian (HF) lactating cows for 53 heads kept intensively at one government dairy station at BBPTU Baturraden, Central Java. Base mutations at 3′UTR location of the OLR1 gene and at K232A mutation of the DGAT1 gene were identified by PCR-RFLP (polymerase chain reaction - restriction fragment length polymorphism) techniques. Allele frequency of the base mutation of each gene was analyzed by PopGen 32 program. Milk components of fat, protein, solid non-fat (SNF) and lactose were generated from daily milk test for morning, afternoon and average of both. Study of the association of variant genotypes of the OLR1 and DGAT1 genes on individual milk component was analyzed by GLM considering the fixed effects of lactation period (1-3, 4-6), calving season (1-4 mo., and 5-8 mo.) and calving year (2011, 2012). Duncan Multiple Range Test was used to test significant differences of the averages among subclasses. The OLR1 gene resulted in A allele and C allele of whose the frequencies were respectively 0.457 and 0.543, while the DGAT1 gene resulted in A allele and K allele with the frequencies respectively 0.426 and 0.575. Variant genotypes of the OLR1 gene gave a significant different on milk fat production (P<0.05). Genetic polymorphism of the OLR1 gene had a significant effect on milk fat content in the noon, the highest was for CC genotype, followed by AC, and the lowest was AA, with the fat contents of CC and AC genotypes higher to AA one by 4.87% and 1.38% respectively. However variant genotypes of the OLR1 gene had no significant effect on other milk components (P>0.05). Similarly, variant genotypes of the DGAT1 gene consisting of genotype AK and genotype KK did not significantly affect on all of milk components. It was concluded that there was a fairly good control of the OLR1 gene to fat content in HF cows. The base mutation at the 3′UTR location of the OLR1 gene can be considered as an initial information in developing a genetic assisted selection (GAS) technique for milk fat content in domestic HF cows.

RNA-seq data reveals a coordinated regulation mechanism of multigenes involved in the high accumulation of palmitoleic acid and oil in sea buckthorn berry pulp

BackgroundSea buckthorn is a woody oil crop in which palmitoleic acid (C16:1n7, an omega-7 fatty acid (FA)) contributes approximately 40% of the total FA content in berry pulp (non-seed tissue). However, the molecular mechanisms contributing to the high accumulation of C16:1n7 in developing sea buckthorn berry pulp (SBP) remain poorly understood.ResultsWe identified 1737 unigenes associated with lipid metabolism through RNA-sequencing analysis of the four developmental stages of berry pulp in two sea buckthorn lines, ‘Za56’ and ‘TF2–36’; 139 differentially expressed genes were detected between the different berry pulp developmental stages in the two lines. Analyses of the FA composition showed that the C16:1n7 contents were significantly higher in line ‘Za56’ than in line ‘TF2–36’ in the mid-late developmental stages of SBP. Additionally, qRT-PCR analyses of 15 genes involved in FA and triacylglycerol (TAG) biosynthesis in both lines revealed that delta9-ACP-desaturase (ACP-Δ9D) competed with 3-ketoacyl-ACP-synthase II (KASII) for the substrate C16:0-ACP and that ACP-Δ9D and delta9-CoA-desaturase (CoA-Δ9D) gene expression positively correlated with C16:1n7 content; KASII and fatty acid elongation 1 (FAE1) gene expression positively correlated with C18:0 content in developing SBP. Specifically, the abundance of ACP-Δ9D and CoA-Δ9D transcripts in line ‘Za56’, which had a higher C16:1n7 content than line ‘TF2–36’, suggests that these two genes play an important role in C16:1n7 biosynthesis. Furthermore, the high expressions of the glycerol-3-phosphate dehydrogenase (GPD1) gene and the WRINKLED1 (WRI1) transcription factor contributed to increased biosynthesis of TAG precursor and FAs, respectively, in the early developmental stages of SBP, and the high expression of the diacylglycerol O-acyltransferase 1 (DGAT1) gene increased TAG assembly in the later developmental stages of SBP. Overall, we concluded that increased ACP-Δ9D and CoA-Δ9D levels coupled with decreased KASII and FAE1 activity is a critical event for high C16:1n7 accumulation and that the coordinated high expression of WRI1, GPD1, and DGAT1 genes resulted in high oil accumulation in SBP.ConclusionOur results provide a scientific basis for understanding the mechanism of high C16:1n7 accumulation in berry pulp (non-seed tissue) and are valuable to the genetic breeding programme for achieving a high quality and yield of SBP oil.

The impact of diacylglycerol O-acyltransferase 1 gene polymorphism on carcass traits in cattle

The aim of this study was to identify the K232A polymorphism in gene encoding diacylglycerol O-acyltransferase 1 (DGAT1) and to evaluate its effect on carcass traits in population of Slovak Pinzgau steers. The genotyping data were obtained for totally 56 animals by using PCR-RFLP method. The A allele (0.93) was more frequent in analysed population than K allele (0.07). Even if the expected and observed heterozygosity indicated prevalence of homozygotes, the significant effect of inbreeding on population structure wasn’t found (FIS=-0.08). The decline in effective allele number (Na=1.15) as well as polymorphic information content (PIC=0.12) pointed out to significant decrease of locus effectiveness in population. The effect of DGAT1 gene polymorphism on carcass traits was tested by using the GLM procedure adopted in SAS 9.3. In association analysis the proportion of muscle, fat, bone, and drip loss within the beef three-rib section were evaluated. However, the statistical analysis showed only non-significant impact of DGAT1 gene polymorphism on selected production traits in analysed population.

Relationship of the bovine IGF1, TG, DGAT1 and MYF5 genes to meat colour, tenderness and cooking loss

Bovine insulin-like growth factor 1 (IGF1), thyroglobulin (TG), diacylglycerol-O-acyltransferase 1 (DGAT1) and myogenic factor 5 (MYF5) genes play an important role in the physiology of lipid and muscle metabolism and are therefore considered as candidate genes for meat production traits in farm animals. The objectives of this study were to investigate single nucleotide polymorphisms (SNPs) in IGF1, TG, DGAT1 and MYF5 genes and to evaluate whether these polymorphisms affected meat colour, tenderness and cooking loss in Holstein cattle. Initially, the SNPs were detected by polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP) method. Meat samples (N= 50) derived from M. longissimus thoracis et lumborum (LTL) were used in the current study. Significant differences in variations of meat colour parameters were observed at 24 hours post-mortem. IGF1 was associated with colour parameters of a* and chroma values. In addition, effects of TG were statistically significant on L* and a* values, while, effects of MYF5 were significant on a* value. There was no association of the tested SNPs with meat pH, tenderness and cooking loss. The results presented here may give the valuable information for improving meat colour in cattle.

Liraglutide Reduces Postprandial Hyperlipidemia by Increasing ApoB48 (Apolipoprotein B48) Catabolism and by Reducing ApoB48 Production in Patients With Type 2 Diabetes Mellitus

Objective- Treatment with liraglutide, a GLP-1 (glucagon-like peptide-1) agonist, has been shown to reduce postprandial lipidemia, an important feature of diabetic dyslipidemia. However, the underlying mechanisms for this effect remain unknown. This prompted us to study the effect of liraglutide on the metabolism of ApoB48 (apolipoprotein B48). Approach and Results- We performed an in vivo kinetic study with stable isotopes (D8-valine) in the fed state in 10 patients with type 2 diabetes mellitus before treatment and 6 months after the initiation of treatment with liraglutide (1.2 mg/d). We also evaluated, in mice, the effect of a 1-week liraglutide treatment on postload triglycerides and analysed in vitro on jejunum, the direct effect of liraglutide on the expression of genes involved in the biosynthesis of chylomicron. In diabetic patients, liraglutide treatment induced a dramatic reduction of ApoB48 pool (65±38 versus 162±87 mg; P=0.005) because of a significant decrease in ApoB48 production rate (3.02±1.33 versus 6.14±4.27 mg kg-1 d-1; P=0.009) and a significant increase in ApoB48 fractional catabolic rate (5.12±1.35 versus 3.69±0.75 pool d-1; P=0.005). One-week treatment with liraglutide significantly reduced postload plasma triglycerides in mice and liraglutide, in vitro, reduced the expression of ApoB48, DGAT1 (diacylglycerol O-acyltransferase 1), and MTP (microsomal transfer protein) genes. Conclusions- We show that treatment with liraglutide induces a significant reduction of the ApoB48 pool because of both a reduction of ApoB48 production and an increase in ApoB48 catabolism. In vitro, liraglutide reduces the expression of genes involved in chylomicron synthesis. These effects might benefit cardiovascular health. Clinical Trial Registration- URL: https://www.clinicaltrials.gov . Unique identifier: NCT02721888.

Transcript analysis at DGAT1 reveals different mRNA profiles in river buffaloes with extreme phenotypes for milk fat

Buffalo DGAT1 (diacylglycerol O-acyltransferase 1) was mainly investigated for the characterization of the gene itself and for the identification of the K232A polymorphism, similar to what has been accomplished in cattle, although no information has been reported so far at the mRNA level. The importance of DGAT1 for lipid metabolism led us to investigate the transcript profiles of lactating buffaloes characterized as high (9.13 ± 0.23) and low (7.94 ± 0.29) for milk fat percentage, and to explore the genetic diversity at the RNA and DNA level. A total of 336 positive clones for the DGAT1 cDNA were analyzed by PCR and chosen for sequencing according to the differences in length. The clone assembling revealed a very complex mRNA pattern with a total of 21 transcripts differently represented in the 2 groups of animals. Apart from the correct transcript (17 exons long), the skipping of exon 12 is the most significant in terms of distribution of clones with 11.6% difference between the 2 groups, whereas a totally different mRNA profile was found in approximately 12% of clones. The sequencing of genomic DNA allowed the identification of 10 polymorphic sites at the intron level, which clarify, at least partially, the genetic events behind the production of complex mRNA. Genetic diversity was found also at the exon level. The single nucleotide polymorphism c.1053C>T represents the first example of polymorphism in a coding region for the DGAT1 in the Italian Mediterranean breed. To establish whether this polymorphism is present in other buffalo breeds, a quick method based on PCR-RFLP was set up for allelic discrimination in the Italian Mediterranean and the Romanian Murrah (200 animals in total). The alleles were equally represented in the overall population, whereas the analysis of the 2 breeds showed different frequencies, likely indicating diverse genetic structure of the 2 breeds. The T allele might be considered as the ancestral condition of the DGAT1 gene, being present in the great part of the sequenced species. These data add knowledge at the transcript and genetic levels for the buffalo DGAT1 and open the opportunity for further investigation of other genes involved in milk fat metabolism for the river buffalo, including the future possibility of selecting alleles with quantitative or qualitative favorable effects (or both).

베이지안 회귀를 이용한 국내 홀스타인 젖소의 유량형질 관련 DGAT1유전자 효과 검증

DGAT1(diacylglycerol O-acyltransferase1) gene is well known as a major gene of milk production in dairy cattle. This study was conducted to investigate how the DGAT1 gene effect on milk yield was appeared from the genome wide association (GWA) using high density whole genome SNP chip. The data set used in this study consisted of 353 Korean Holstein sires with 50k SNP genotypes and deregressed estimated breeding values of milk yield. After quality control 41,051 SNPs were selected and locations on chromosome were mapped using UMD 3.1. Bayesian regression of BayesB method (pi

Association of polymorphisms at DGAT1, leptin, SCD1, CAPN1 and CAST genes with color, marbling and water holding capacity in meat from beef cattle populations in Sweden

The objective of this study was to investigate the associations of single nucleotide polymorphisms (SNPs) at five candidate genes with meat pH, color, marbling and water holding capacity (WHC) in young bulls from five beef breeds (n=243) in Sweden. The UASMS2 polymorphism at the leptin gene and the SNPs at the Stearoyl-CoA desaturase 1 gene (SCD1.878) and μ-calpain gene (CAPN1:c.947) were associated with variation in meat color traits after 6days of exposure to air. The K232A polymorphism at the diacylglycerol O-acyltransferase 1 (DGAT1) gene and the CAPN1:c.947 SNP were associated with level of beef marbling. There was no association between the SNP at the calpastatin gene (CAST:c.155) and meat quality traits, nor was there any association of the tested SNPs with WHC traits and pH value.

Identification of novel single nucleotide polymorphisms in the DGAT1 gene of buffaloes by PCR-SSCP

Diacylglycerol O-acyltransferase 1 (DGAT1) is a microsomal enzyme that catalyzes the final step of triglyceride synthesis. The DGAT1 gene is a strong functional candidate for determining milk fat content in cattle. In this work, we used PCR-SSCP (polymerase chain reaction-single-strand conformation polymorphism) and DNA sequencing to examine polymorphism in the region spanning exon 7 to exon 9 of the DGAT1 gene in Murrah and Pandharpuri buffaloes. Three alleles (A, B and C) and four novel single-nucleotide polymorphisms were identified in the buffalo DGAT1 gene. The frequencies of the alleles differed between the two buffalo breeds, with allele C being present in Murrah but not in Pandharpuri buffalo. The allele variation detected in this work may influence DGAT1 expression and function. The results described here could be useful in examining the association between the DGAT1 gene and milk traits in buffalo.

The effect of sex and DGAT1 gene polymorphism on fat deposition traits in simmental beef cattle

This study investigated diacylglycerol O-acyltransferase 1 (DGAT1) gene K232A mutation in Simmental cattle and its effects on fat deposition traits. The sample (n=26) consisted of yearling bulls and beef heifers from an intensive rearing system in Croatia. Carcass fatness was assessed by total dissection method, whereas intramuscular fat (m. longissimus dorsi) content was determined using Soxhlet extraction with hydrolysis. Intramuscular fatty acid composition was determined by gas liquid chromatography using in situ transesterification. The muscle DNA was extracted and Polymerase Chain Reaction-Restriction Fragment Length Polymorphism (PCRRFLP) analysis of the 411 bp fragment of DGAT1 gene was applied. The DGAT1 K allele was less frequent in heifers than in bulls, with the overall allelic frequency of 17% K allele. Only KA and AA genotypes were obtained, without deviation from the Hardy-Weinberg equilibrium. Heifers showed a higher degree of carcass and muscle fattening with more unsaturated intramuscular fat than bulls; however, there was no interaction between sex and DGAT1 gene. Generally, no significant difference between DGAT1 AA and KA animals was observed for any of the examined traits, except the slightly higher carcass share of the fattest beef category and higher intramuscular C14:0 desaturation index in KA heterozygous.

Yak DGAT1 gene: Cloning, tissue expression profile, splicing and polymorphism analysis

The objective of the present study was to reveal the characteristics of diacylglycerol O-acyltransferase 1 (DGAT1) gene of high altitude yak (Bos grunniens). Two mRNA sequences of yak DGAT1, including a full length and a spliced isoform deleted with 66 nucleotides in exon VIII, were cloned from Jiulong yak liver by reverse transcription polymerase chain reaction (RT-PCR). The coding sequence (CDS) of yak full length DGAT1 gene is 1470bp, sharing 99.5% of nucleotide sequence homology and 100% of amino acid sequence homology with those of cattle, respectively. PCR analysis using DNA and RNA as templates demonstrated the alternative splicing of yak DGAT1 gene and estimated the proportion of the spliced isoform as approximately 30% of the total DGAT1 mRNA in yak liver and biceps femoris. Quantitative real-time RT-PCR analysis showed that both adult yak and cattle had significantly higher DGAT1 mRNA level in liver and adipose tissue than in skeletal muscles (P<0.05), while no difference was observed between the corresponding tissues of yak and cattle, suggesting that yak DGAT1 gene might not be responsible for the lower intramuscular fat content in yaks compared to cattle. Allelic variation at nucleotide positions 10433 and 10434 (K232A) of the DGAT1 gene of yak and cattle was detected by polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) method. Nearly all yaks (n=81) examined were homozygous for the K allele, while Chinese Holstein cows showed high frequency for the A allele. The K allele of yak DGAT1 gene might be correlated with its higher milk fat content characteristic.

Productive performance of the dairy cattle Girolando breed mediated by the fat-related genes DGAT1 and LEP and their polymorphisms

Candidate genes have been associated with milk production in bovines, such as the diacylglycerol O-acyltransferase 1 (DGAT1) and leptin (LEP); however, they have not been simultaneously investigated nor have been evaluated in the Brazilian Girolando breed (Gir × Holstein, backcrossed to Holstein). Our aim was to determine the influence of fat-related genes, DGAT1 and LEP, and their polymorphisms on performance traits of milk production in the Girolando breed. Results indicated that the K allele of the DGAT1 gene showed a significant association with total and average daily milk production with additive effect. The LEP gene showed that the A allele and its homozygote are highly prevalent and almost fixed in this population and may have been favorably selected during backcrossing for the origin of this breed. The important impact of the K allele of the DGAT1 gene on milk production corroborates the initiative of performing marker-assisted selections with this gene in breeding programs of the Girolando breed.