MODULATION OF CONNEXIN 43 AND INTEGRIN α5β1 BY STARD7 siRNA IN HTR8/SVNEO CELLS

LA FALDA-CORDOBA

Jornada; XXI JORNADAS CIENTIFICAS Sociedad de Biología de Córdoba; 2017

SOCIEDAD DE BIOLOGÍA DE CÓRDOBA

StarD7 belongs to START domain protein family, which is involved in lipid transport, metabolism and signaling. Previous results from exploratory differential gene expression analysis in JEG-3 cells transfected with StarD7 siRNA suggest that connexin 43 (Cx43) mRNA was abundantly downregulated. In the present study we address the effect of StarD7 siRNA on Cx43 expression and its association with several extracellular matrix (ECM) proteins. Data from qPCR and western analysis demonstrated a decrease in Cx43 mRNA and protein levels in the derived-first trimester trophoblast HTR8/SVneo cells transfected with StarD7 siRNA compared to control siRNA. Additionally, a significant increase in the mRNA and protein levels of integrin α5 in silenced cells was determined by qRT-PCR, western blot, and immunofluorescence assays. Also, a clear increase in the transcript level of integrin β1, as well as in the mature β1 protein was detected. Furthermore, StarD7 silencing leads to an increase in β-catenin protein and nidogen-1 mRNA levels, as well as in the amount of MMP9 secreted to the culture medium. Collectively, our studies indicate that StarD7 siRNA- transfected HTR8/SVneo cells express significantly less Cx43 and this outcome is correlated with increased content of ECM-associated proteins.