Study On The Expression Of Heat Shock Protein 90(HSP90)Gene In Daheng Broiler And Its Effects On Chicken Adipocyte Differentiation

Adipose plays an important role in maintaining vital activities,growth and reproduction of animal organisms.Some studies in mammals have shown that HSP90,a molecular chaperone protein of PPARγ,play an important role in the process of adipogenesis by regulating the structural stability of PPARγ.However,the mechanism of HSP90 regulation mechanism by regulating PPARγ in poultry is unknown.Fat deposition of poultry is closely related to meat quality.And it is mainly the result of proliferation and differentiation of adipocyte.Therefore,the study on poultry adipocyte plays an important role in poultry breeding.In the current study,Daheng broilers were adopted.The low abdominal fat Lohmann layer was used as a control to study the different expression abundances of HSP90 in abdominal fat and liver between broiler and layers as well as the possible effect of HSP90 on adipocyte proliferation and differentiation.Results showed that:Traits of weight,liver weight,and fat deposition(abdominal fat and relative abdominal fat weight)of Daheng broiler were significantly higher than those of Lohmann layer(P < 0.05).In terms of fat cell morphology,the area and diameter of Daheng broiler were significantly larger than those of Lohmann layer.The density of Daheng broiler was significantly lower than that of Lohmann layer(P < 0.05);The expression abundances of HSP90 on d 14,21,35,and 42,PPARγ on d 7,14,21,35,and 42,FAS on d 14,21,and 35 and SREBP-1C on d 21,35,and 42 in the abdominal fat were significantly higher than those of Lohmann layer(P < 0.05);The expression abundances of HSP90 on d 14,21,35,and 42,PPARγ on d 35,and 42,FAS on d 14,21,35,and 42,and SREBP-1C on d 35 in the liver of Daheng broilers were significantly higher than those of Lohmann layers(P < 0.05).After oleic acid induction,the cells began to enter the differentiation stage,and small lipid droplets began to form in the cells,and gradually increased with the prolongation of the culture time,and the number of small lipid droplets in the cells increased and gradually polymerized into large lipid droplets,stored in mature adipocytes.The expression abundances of HSP90、PPARγ,and SREBP-1c genes in adipocyte increased with the oleic acid induction and were significantly higher at 24 h and 48 h than the previous time points(P < 0.05).The expression abundance of HSP90 gene and protein in adipocytes decreased significantly after transfection(P < 0.05).HSP90 interference significantly decreased the differentiation of adipocyte and triglyceride accumulation in cellular.Cell proliferation was not affected by HSP90 interference significantly.HSP90 interference significantly decreased the gene and protein expression abundances of PPARγ,FAS and SREBP-1C.The expression of HSP90 m RNA and protein in adipocytes increased significantly after transfection by PUC57-HSP90(P < 0.05).The differentiation of adipocyte and triglyceride accumulation in adipocyte were significantly accelerated.Cell proliferation was not affected by PUC57-HSP90 significantly.PUC57-HSP90 significantly increased the gene and protein expression abudances of PPARγ,FAS,and SREBP-1c(P < 0.05).Generally,HSP90 gene was involved in the regulation process of chicken lipid metabolism and the interference and overexpression results revealed that HSP90 could regulate adipocyte differentiation by regulating the expression of PPARγ and other adipocyte-differentiation related genes.