Effect of Breed on Transcriptional and Protein Expression of Lipogenic Enzymes in Tail and Subcutaneous Adipose Tissue from Two Grazing Breeds of Lambs

Abstract

This experiment was carried out to determine the effect of breed on mRNA and protein expression levels of lipogenic enzymes acetyl-CoA carboxylase α (ACC), fatty acid synthase (FAS), stearoyl-CoA desaturase 1 (SCD1) plus sterol regulatory element binding transcription factor 1c (SREBP1c) in the subcutaneous fat (SCF) from the back of the animal, and tail fat (TF) of both Chilota and Suffolk Down lambs grazing Calafatal. Eight Chilota and six Suffolk Down 2-month-old male lambs were allocated to graze a “Calafatal”, a typical secondary succession of Chiloé Archipelago, Chile. After 62 d, lambs were slaughtered according to Chile’s meat industry standards. Fatty acid profile, RT-qPCR, and Western blot analyses from SCF and TF samples were performed. Although the mRNA expression levels of ACC, FAS, SCD1 and SREBP1c in SCF did not differ significantly between breeds (p > 0.05), a trend to higher mRNA expression of FAS and SREBP1c in TF from Chilota lambs was observed (p = 0.06). On the other hand, FAS levels in SCF were higher in Chilota than in Suffolk Down lambs (p < 0.02), although Suffolk Down showed higher fat contents and saturated fatty acid (SFA) proportions than Chilota lambs (p < 0.01). The FAS protein expression in TF was similar in both breeds (p > 0.05). Although the fat content was higher in Suffolk Down than in Chilota lambs (p < 0.01), the SFA proportions were similar in both breeds. Finally, it can be concluded that although mRNA expression of enzymes was similar in both breeds, there were differences in some protein levels in the SCF, partially related with the fatty acid profiles, thus affecting the selection of lamb breed either for human consumption or experimental purposes.

Quantitative proteomic analysis identified differentially expressed proteins with tail/rump fat deposition in Chinese thin- and fat-tailed lambs

“…ACSL1 is essential for the synthesis of the progress of adipogenic differentiation culminating in triacylglycerol synthesis and storage [ 44 ]. In our data, we noticed that ACSL1, ACACA, ACLY, and FASN were up-regulated in the three FTS breeds, which are in agreement with the previous transcriptome analysis on other sheep breeds [ 41 , 43 ]. Nevertheless, ATGL and HSL are the two main lipases and are responsible for 95% of the lipolysis in adipose tissue [ 45 ].…”

“…in agreement with the previous transcriptome analysis on other sheep breeds [41,43]. Nevertheless, ATGL and HSL are the two main lipases and are responsible for 95% of the lipolysis in adipose tissue [45].…”

“…PPAR signaling pathway plays key roles in regulating cellular differentiation and cell proliferation [ 11 ], which was identified as the frequently used pathway related to the fat deposition [ 26 , 53 ]. PPAR signaling pathway genes (including FABP4 , FABP5 , ACSL1 , ACSL6 , PLIN1 , PLIN4 , SCD , LPL , ACAA1 , and ADIPOQ ) were reported as up-regulated DEGs in TAT of other FTS in comparison with TTS breed previously [ 10 , 11 , 27 – 29 , 41 , 43 , 51 ]. All these genes also have been investigated by RT-qPCR in the present study, which were consistent with these previous studies.…”

“…The synthesis and degradation of fatty acids determining deposition or utilization of depot fat in adipose tissue [ 42 ]. There are several functional candidate genes associated with fat deposition and adipogenesis in FTS [ 3 ], including ACSL1, ACACA, ACLY, FASN, ATGL and HSL, which also were validated and considered as the key factors determining lipid metabolism in fatty tissues [ 26 , 41 , 43 ]. ACSL1 is essential for the synthesis of the progress of adipogenic differentiation culminating in triacylglycerol synthesis and storage [ 44 ].…”

Comparison and analysis on sheep meat quality and flavor under pasture-based fattening contrast to intensive pasture-based feeding system

“…From the results presented in the study, the most abundant fatty acid was oleic acid (C18:1) (31.63-36.91%), then palmitic acid (C16:0, 24.61-27.54%) and stearic acid (C18:0, 18.84-20.65%) in both groups of production systems. The total percentages of the three dominant fatty acids in the CON and PAS group were 78.01% and 82.17% respectively, which were in line with the data of previous researches [32][33][34].…”