- Estimates of genomic heritability and genome-wide association study for fatty acids profile in Santa Inês sheep. - Twenty-seven genomic regions of 10 adjacent SNPs associated with fatty acids composition were identified on chromosomes and 18, each explaining ≥ 0.30% of the additive genetic variance. - In par- ticular, consumers are becoming gradually concerned relative to the amount of fatty acids in red meat [2].. - Meat produced by ruminants is generally related to higher levels of saturated fatty acids (SFA), which are widely associated with the development of heart disease, stroke, diabetes, and obesity [3–5].. - On the other hand, moderate levels of consumption of monounsaturated fatty acids (MUFA) are related to a de- crease in serum cholesterol, consequently reducing the. - Although found in a smaller proportion, red meat is also com- posed of polyunsaturated fatty acids (PUFA), which are strictly essential because they are not synthesized by humans and thus must be consumed daily to maintain proper body function [9]. - These fatty acids influence several metabolic functions such as cell signaling, en- zymatic regulation, eicosanoid synthesis, regulation of neuronal migration, neuromodulatory activity, and neurotransmitter activity [10, 11].. - Fatty acids are complex traits, with several factors af- fecting their composition, such as sex, diet, age, and genetics [12]. - An important first step for the genetic evaluation of fatty acids content in meat is to investigate the genetic architecture of these complex traits and to identify variants associated with genes or regulatory elements through a genome-wide association study (GWAS) [18].. - Thus, the objec- tives of this study were to estimate genomic heritabilities and, for the first time, identify regions and candidate genes associated with fatty acid profiles in the Longissi- mus dorsi muscle of sheep using bivariate models.. - and myristic (C corresponding to about 95% of the SFA present in the Longissimus dorsi muscle. - C18:1 is one of the main fatty acids in the Mediterranean diet, where several studies report a. - which corresponded to approximately 61% of PUFA and made up about 77% of ω6 fatty acids.. - The concentrations of ω 3t fatty acids for this study were low, less than 1% of the total fatty acids. - Alpha-linolenic acid (C18:3 ω3) had the highest concentration, making up 37% of the ω 3t fatty acids. - however, only 0.37% of the total fatty acids. - Conjugated linoleic acid (CLA c9t11) corresponded to about 7% of the PUFA, and only 0.43% of the total fatty acids. - Estimates of genomic heritability for fatty acids traits from the current study were between 0.25 and 0.46 (Table 2). - Moderate genomic heritability estimates for C and C acids were obtained in the present study. - Although the genomic heritabilities of fatty acids are of different magnitude compared to the literature, it was possible to observe some consistency in the results, where higher estimates of genomic heritabilities were al- ways obtained for C14:0, C16:0, C18:0, C16:1 and C18:1.. - Saturated fatty acids. - Table 3 Genomic regions and candidate genes associated with the saturated fatty acid (SFA) profile of the Longissimus dorsi muscle of Santa Inês sheep. - One of the Gene Ontology (GO) terms related to this gene is cellular apoptosis (GO:0006915), playing an important role in the induc- tion of apoptosis by saturated fatty acids in several cells . - In the first region two PCG were identified, TPH2 (tryptophan hydroxylase 2) and TRHDE (thyrotropin releasing hormone degrad- ing enzyme). - In the region on chromosome 16 at 55 Mb, the CDH12 (cadherin 12) gene was found, which was associ- ated with the C14:0 and C18:0 content in milk of Holstein cows and with the Wnt signaling pathway [61].. - DGAT2 (diacylglycerol o-acyltransferase 2), which is an important gene associated with the catalysis of the final stage of triacylglycerol biosynthesis [66] was identi- fied in the region of chromosome 15 at 52.85 Mb. - 1 Manhattan plot for the proportion of genetic variance explained by windows of 10 adjacent SNPs for saturated fatty acids in the Longissimus dorsi muscle of Santa Inês sheep. - In the regions of chromosome 3 at 109 Mb and chromosome 14 at 11 Mb, no candidate genes were identified.. - Monounsaturated fatty acids. - The COPB2 gene plays an essential role in the Golgi membrane (GO:0000139) and metabolic pathways related to the transport of cholesterol and sphingolipid of the Golgi complex and the endoplasmic reticulum to the plasma membrane in the region (GO:0006888).. - In the second region located on chromosome 5 at 69 Mb, no candidate genes were found. - Two regions of chromosome 3 at 107.8 and 109 Mb associated with C16:1 were found, however in the second, no candidate genes were identified. - Because C16:0 acid is a precursor of C16:1 (desaturation) and C18:0 (elongation) [68] and is related to the SFAt, it is expected that there are common genetic mechanisms for these fatty acids.. - In the region of chromosome 8 at 28 Mb two candi- date genes FOXO3 (forkhead box O3) and OSTM1 (osteopetrosis associated transmembrane protein 1) were associated with C16:1. - Unsaturated or saturated fatty acids play an essential role in cell apoptosis process, such as hepatocytes [70]. - Table 4 Genomic regions and candidate genes associated with the monounsaturated fatty acids (MUFA) profile of the Longissimus dorsi muscle of Santa Inês sheep. - Polyunsaturated fatty acids. - In the region of chromosome 8 at 35 Mb, no PCG were found.. - In the region of chromosome 5 at 35 Mb, the candidate gene identified was the TNFAIP8 (tumor necrosis factor, alpha-induced protein 8). - 2 Manhattan plot for the proportion of genetic variance explained by windows of 10 adjacent SNPs for monounsaturated fatty acids in the Longissimus dorsi muscle of Santa Inês sheep. - Table 5 Genomic regions and candidate genes associated with the polyunsaturated fatty (PUFA) acids profile of the Longissimus dorsi muscle of Santa Inês sheep. - In the region located on chromosome 8 at 10 Mb the ME1 (malic enzyme 1) and UBE3D (ubiquitin-protein ligase E3D) genes were identified. - In a general context, the function of the ubiquitin-proteasome path- way can be controlled physiologically, in part, by fatty acids within cellular membranes [79].. - PLCXD3 gene was related to phospholipases, a group of enzymes that hydrolyze the phospholipids in fatty acids and other lipophilic molecules (GO:0016042).. - In the region of chromosome 18 at 55 Mb, related to C18:3 ω3, the PCG were CCDC88C (coiled-coil domain containing 88C) and FBLN5 (fibulin-5). - For CLA c9t11, two genomic regions were found in the region on chromosome 3 at 212 Mb, the PCG. - 3 Manhattan plot for the proportion of genetic variance explained by windows of 10 adjacent SNPs for polyunsaturated fatty acids in the Longissimus dorsi muscle of Santa Inês sheep. - Long chain fatty acids are involved in the calcium channel activation processes, possibly acting at some nearby lipid binding sites on these channels or directly over the channel protein itself [83–85]. - In the region of chromosome 12 at 49 Mb, no PCG related to CLA c9t11 was observed.. - In the region of chromosome 15 at 58 Mb, none candidate gene was found. - This result is expected since C18:3 ω3 is one of the most abundant ω3 acids, and consequently, it is directly involved in the ω6/ω3 ratio.. - For the PUFA/SFA ratio, only one region on chromosome 3 at 107.8 Mb, common to several individual fatty acids and groups of the fatty acids (C16:0, C16:1, PUFAt, SFAt, C18:2 ω6, and ω6t). - This was expected given the PUFA/SFA ratio uses all these fatty acids for its calculation.. - In the present study, important genomic regions asso- ciated with fatty acids profile were identified, providing an improved biological understanding of fatty compos- ition in ovine. - This was expected since from the quantitative genetics point of view, meat fatty acids profile is a com- plex trait controlled by multiple genes and is influenced by several loci throughout the genome [86]. - Thus, this research is the first step toward understand- ing the genetic and metabolic mechanisms involved in the phenotypic determination of fatty acids in sheep meat. - Table 6 Genomic regions and candidate genes associated with the ω 6/ ω 3 and PUFA/SFA ratios of the Longissimus dorsi muscle of Santa Inês sheep. - The extraction, methylation and reading steps for the determination of fatty acid composition in the Longissi- mus dorsi (30 g) muscle were conducted at the Animal Nutrition and Growth Laboratory at ESALQ (Piracicaba, São Paulo, Brazil). - One μL of the. - 4 Manhattan plot for the proportion of genetic variance explained by windows of 10 adjacent SNPs for PUFA/SFA and ω 6/ ω 3 ratios in the Longissimus dorsi muscle of Santa Inês sheep. - esterified extract was injected in the chromatographer.. - The fatty acids were identified by comparison of the retention times of methyl esters in the samples with standards of fatty acids from butter reference BCR-CRM 164, Anhydrous Milk Fat-Producer (BCR Institute for Materials and Reference Measurements) and also with commercial standard for 37 fatty acids Supelco TM Component FAME Mix (cat 18,919, Supelco, Bellefonte, PA). - Fatty acids were quantified by normalizing the areas of methyl esters. - Fatty acids were expressed as a weight percentage (mg/mg), obtained using ChromQuest 4.1 software (Thermo Electron, Milan, Italy).. - After extraction, 47 different fatty acids were obtained from the Logissimus dorsi muscle of Santa Inês sheep. - Of these, the following fatty acids were selected: myristic (C14:0), palmitic (C16:0), stearic (C18:0), palmitoleic (C16:1), oleic (C18:1, cis-9), linoleic (C18: 2 ω6), conjugated linoleic acid (CLA c9t11) and alpha-linolenic (C18: 3 ω3).. - These individual fatty acids were selected considering their importance for human health and abundance in the samples evaluated. - For GWAS the effects of the SNPs. - Since the fatty acids traits evaluated in this study seem to be controlled mainly by many QTL of small effect, identifying large effect genes will be difficult, given each marker has a minor contribution to the total genetic variation. - Consequently, only genomic regions explain- ing the largest proportion of additive genetic variation, above 0.30%, were considered to determine the possible QTL regions associated with fatty acids profile traits.. - FA: Fatty acid. - MUFA: Monounsaturated fatty acid;. - MUFAt: Total monounsaturated fatty acid. - PUFA: Polyunsaturated fatty acid. - PUFAt: Total polyunsaturated fatty acid;. - SFA: Saturated fatty acid. - SFAt: Total saturated fatty acid. - ω 3t: Total of omega 3 fatty acids. - ω 6t: Total of omega 6 fatty acids. - Genome-wide association and prediction of direct genomic breeding values for composition of fatty acids in Angus beef cattle. - Monounsaturated fatty acids prevent the aversive effects of obesity on locomotion, brain activity, and sleep behavior. - Monounsaturated 14:1n- 9 and 16:1n-9 fatty acids but not 18:1n-9 induce apoptosis and necrosis in murine HL-1 cardiomyocytes. - The role of polyunsaturated fatty acids in restoring the aging neuronal membrane.. - Influence of marine n-3 polyunsaturated fatty acids on immune function and a systematic review of their effects on clinical outcomes in rheumatoid arthritis. - Polyunsaturated fatty acids and their metabolites in brain function and disease. - Influence of stearic acid on cholesterol metabolism relative to other long chain fatty acids. - Dietary monounsaturated fatty acids are protective against metabolic syndrome and cardiovascular disease risk factors. - Role of cis-monounsaturated fatty acids in the prevention of coronary heart disease. - saturated fatty acids ratios and peroxidisability index values of dietary. - Intake of fatty acids in general populations worldwide does not meet dietary. - Fatty acids and immune responses – a new perspective in searching for clues to mechanism. - Saturated, but not unsaturated, fatty acids induce apoptosis of human coronary artery endothelial cells via nuclear factor- B activation. - Saturated fatty acids induce endoplasmic reticulum stress and apoptosis independently of ceramide in liver cells. - Differential roles of unsaturated and saturated fatty acids on autophagy and apoptosis in hepatocytes. - Fatty acids regulate pigmentation via proteasomal degradation of tyrosinase: a new aspect of ubiquitin-proteasome function. - Regulatory potential of n-3 fatty acids in immunological and inflammatory processes. - Pleiotropic effects of polymorphism of the gene diacylglycerol-O-transferase 1 (DGAT1) in the mammary gland tissue of dairy cows. - Long-chain fatty acids activate calcium channels in ventricular myocytes. - Suppression of voltage- gated L-type Ca2+ currents by polyunsaturated fatty acids in adult and neonatal rat ventricular myocytes. - Prostaglandins Leukot Essent Fatty Acids
Xem thử không khả dụng, vui lòng xem tại trang nguồn hoặc xem
Tóm tắt