The Regulation of Calcium-binding Protein S100A4 on Autophagy in THP-1 Cells Infected with Bacillus Calmette-Guérin
The purpose of this study was to explore the regulatory effect of calcium-binding protein S100A4 on autophagy of human monocyte-macrophage THP-1 cells infected with Bacillus Calmette-Guérin(BCG).BCG infected THP-1 cells at different times(MOI=10).The expressions of S100A4 and LC3 proteins were detected by Western blot,and the number of autophagosomes was observed by transmission electron microscopy(TEM).After BCG infection alone or co-treatment with S100A4 small interfering RNA for 12 h,the mRNA expression of S100A4 and autophagy-related factors,LC3 Ⅱ(microtubule-associated protein light chain 3 Ⅱ),Atg7(autophagy-related gene 7),and Beclin1,were detected by qRT-PCR.The protein expressions of S100A4,LC3 Ⅱ,Atg7,and Beclin-1 were detected by Western blot.Autophagy flow was detected by mRFP-GFP-LC3,and spot aggregation of mRFP-LC3 and mRFP-GFP-LC3 was observed by laser confocal microscopy.After BCG was infected with THP-1 cells at different times,the protein expression levels of S100A4 and LC3 Ⅱ firstly increased and then decreased with the extension of infection time,and the expression levels were the highest at 12 h(P＜0.001),and the number of autophagosomes increased significantly.mRNA levels of S100A4,LC3Ⅱ,Atg7,and Beclin-1 in the siNC+BCG infection group were significantly up-regulated compared with those in the siNC group(P＜0.05),S100A4,LC3 Ⅱ,Atg7,and Beclin-1 were significantly expressed at mRNA level after BCG and siS100A4 treatment(P＜0.05)or very significantly(P＜0.01,P＜0.001)down-regulated;Protein levels of S100A4,LC3 Ⅱ,Atg7,and Beclin-1 increased significantly compared with an uninfected group(P＜0.05),the protein expression levels of S100A4,LC3 Ⅱ,Atg7,and Beclin-1 were significantly reduced after BCG and siS100A4 treatment(P＜0.001);Compared with the uninfected group,the number of autophagosomes in BCG group was significantly increased(P＜0.01),the number of autophagosomes in siS 100A4+BCG group was significantly reduced compared with siNC+BCG infection group(P＜0.05).S100A4 has a regulatory effect on the autophagy of macrophages induced by BCG infection,and S100A4 can promote the BCG-induced autophagy of THP-1 cells.
国家科技期刊平台
NSTL
万方数据
维普
