Professor Clemson University Clemson, South Carolina
Abstract: The presence of subcutaneous adipose tissue in excess on a carcass can significantly contribute to financial losses for the producer and processor. Technology with the potential to limit this excess accumulation of adipose tissue could provide another avenue to improve animal efficiency. Stearoyl-CoA desaturase 1 (SCD1) has been identified as a potential genetic target, as it seems tohave a crucial role in fatty acid metabolism. MiR-199a-3p has been reported to alter the expression of SCD-1, in-vitro, in mouse adipocytes; a connection has yet to be formed in large mammal adipocytes. Texel-Suffolk (n=5) and Suffolk-Suffolk (n=4) cross lambs were finished to 203 days of age, and subcutaneous fat was harvested. Primary pre-adipocytes were isolated from both breeds. Pre-adipocytes were then propagated, differentiated, and treated over a 3-day period. Treatments consisted of controls, AgomiR-199a-3p (50nm), and AntagomiR-199a-3p (500nm). Cells were harvested daily over the 3 days to determine if day-to-day differences were present. MiR-199a-3p expression was upregulated in AgomiR treatments compared with controls beginning on d 1 to 3 (P < 0.05). MiR-199a-3p expression in the AgomiR treatment was upregulated more on day 1 in comparison with d 2 and 3 (P < 0.05). MiR-199a-3p expression was downregulated in AntagomiR treatments compared with controls beginning on d 1 to 3 (P < 0.05). MiR-199a-3p expression in the AntagomiR treatment was downregulated more on d 2 in comparison with d 1 and 3 (P < 0.05). MiR-199a-3p expression did not differ between the non-treatment control and Lipofectamine control over the treatment period (P > 0.05). Data showed no significant alteration in SCD-1 expression between treatments or between days (P > 0.05). MiR-199a-3p expression can be altered using AgomiR and AntagomiRs, but SCD-1 expression is unaffected. Thus, additional research is needed to examine targets of miR-199a-3p in ovine.