Project description:Domestic chicken has been intensively studied because of its role as an efficient source of lean meat. However, commercial broilers resulting from genetic selection for rapid growth demonstrate detrimental traits, such as excess deposition of abdominal adipose tissue, metabolic disorders, and reduced reproduction. Therefore fast-growing broilers represent “obese” chickens compared to slow-growing egg layers (e.g, Leghorn) or wild strain of meat-type chickens (e.g., Fayoumi). Fayoumi chickens, originating from Egypt, represent a harder stain of chickens, which are more resistant to diseases. Leghorn chickens are the original breed of commercial U.S layers. Both lines were maintained highly inbred by Iowa State University poultry geneticists with an inbreeding coefficient higher than 0.95. Both Fayoumi and Leghorn demonstrated lean phenotype compared to broilers, and these three lines of chickens are genetically distant from each other. In this study, we used affymetrix microarray to profile global gene expression of three distinct genetic lines of chickens to identify functional pathways associated with leanness of domestic chickens.
Project description:Purpose: The goals of this study are to investigate the differentially expressed genes between High IMF chickens (WC) and Low IMF chickens (WRR) breast muscles by Illumina deep sequencing, to reveal the mechanism underlying chicken IMF deposition. Methods: Both WC chickens and WRR chickens were raised up to 120 d of age (D120) or 180 d of age (D180), two female birds of similar weight from each breed per age were subjected to RNA-sequencing by Illumina Hiseq 2000. So eight muscle samples in total were subjected to RNA-seq analysis, four WC chicken samples including WC.D120.B-1, WC.D120.B-3, WC.D180.B-2 and WC.D180.B-3, and four WRR chicken samples including WRR.D120.B-4, WRR.D120.B-6, WRR.D180.B-2 and WRR.D180.B-5. Results: The clean reads of each sample were over 20 million, the expressed genes ranged from 16202 to 17838, and a little higher in WRR samples than in WC samples. Differentially expresse analysis showed that there were 525, 161, 23, 87 DEGs detected in the comparisons of WRR.D120.B-VS-WC.D120.B, WRR.D180.B-VS-WC.D180.B, WC.D120.B-VS-WC.D180.B and WRR.D120.B-VS-WRR.D180.B, respectively. Many genes related to lipid catabolism were down-regulated in WC chickens. Conclusions: Our present study suggest that lower lipid catabolism exists in WC chickens but not in WRR chickens, and lower expression of SLC27A1 is through down-regulating fatty acid oxidation mediated by CPT1A to facilitate IMF deposition. Moreover, these findings indicate that reduced lipid catabolism, rather than increased lipid anabolism, contributes to chicken IMF deposition.
Project description:Transcriptional profiling of abdominal adipose tissue in juvenile broiler chickens divergently selected for abdominal fatness or leanness
Project description:Leanness is associated with increased lifespan and is linked to favorable metabolic conditions promoting life extension. We show here that deficiency of the lipid synthesis enzyme acyl CoA:diacylglycerol acyltransferase 1 (DGAT1), which reduces body fat in mice, promotes longevity. Female DGAT1-deficient mice were protected from age-related increases in body fat, non-adipose tissue triglycerides, and markers of inflammation in white adipose tissue. These metabolic changes were accompanied by an increased mean and maximal lifespan of ~25% and ~10%, respectively. The gene expression profile of DGAT1-deficient mice was not highly correlated with calorie restriction of sex and age matched wild-type littermates. Our findings indicate that loss of DGAT1-mediated lipid synthesis results in leanness, protects against age-related metabolic consequences, and thus extends longevity.
Project description:RNA sequencing analysis of abdominal adipose tissue in 7 week old juvenile broiler chickens divergently selected for abdominal fatness or leanness
Project description:Leanness is associated with increased lifespan and is linked to favorable metabolic conditions promoting life extension. We show here that deficiency of the lipid synthesis enzyme acyl CoA:diacylglycerol acyltransferase 1 (DGAT1), which reduces body fat in mice, promotes longevity. Female DGAT1-deficient mice were protected from age-related increases in body fat, non-adipose tissue triglycerides, and markers of inflammation in white adipose tissue. These metabolic changes were accompanied by an increased mean and maximal lifespan of ~25% and ~10%, respectively. The gene expression profile of DGAT1-deficient mice was not highly correlated with calorie restriction of sex and age matched wild-type littermates. Our findings indicate that loss of DGAT1-mediated lipid synthesis results in leanness, protects against age-related metabolic consequences, and thus extends longevity. Liver gene expression profiles between short-term calorie restricted wild-type (WTCR) and Dgat1 deficient (KO) middle-aged (15-16 mo) female mice were compared to determine if calorie restriction and Dgat1 deficiency rely on common regulatory pathways for the promotion of longevity. Both CR and KO were compared to middle-aged wild-type female littermates fed a standard chow diet ad libitum (WTAL).