斑马鱼Ctsba在脂肪细胞分化中的功能OA北大核心CSTPCD

To explore the role of cathepsin B(Ctsb)in adipocyte differentiation in zebrafish(Danio re-rio),we investigated the effects of Ctsb on adipocyte precursors(3 T3-L1)differentiation in mice using gene overexpression and knockout techniques.Bioinformatics analysis showed that there were two ca-thepsin B genes(ctsb)in the zebrafish genome:cathepsin ba(ctsba)and cathepsin bb(ctsbb),in which the amino acid sequence encoded by zebrafish ctsba is more similar to that of mammalian CTSB,and their secondary and tertiary structures are also very similar.In adult zebrafish,ctsba gene is expressed in different tissues such as ovary,adipose tissue,testis,muscle,spleen,intestine,heart,kidney,gill,brain and liver,with higher expression in ovary,adipose tissue and testis.Overexpression of zebrafish ctsba in 3 T3-L1 cells by lentiviral expression vector can significantly increase the formation of lipid drop-lets.However,knockdown of endogenous ctsb gene significantly reduced the formation of lipid drop-lets,suggesting that ctsba can promote the differentiation of 3 T3-L1 adipocyte precursor cells into adi-pocytes.In addition,real-time quantitative PCR showed that overexpression of ctsba could up-regulate the expression of P P ARγ,C/EBP-α,FAS,ACC1 and FABP4 lipogenic genes in zebrafish,while knockout of ctsb gene was opposite.In conclusion,this study revealed the function of Ctsba in regula-ting adipocyte differentiation in zebrafish.