Role of intracellular Ca2+ in regulating NHE3 expression in Caco-2 cells during rotavirus infection / 中华微生物学和免疫学杂志

ABSTRACT

Objective To investigate the effects of rotavirus ( RV) on the expression and bioactiv-ity of Na+-H+ exchanger 3 ( NHE3 ) in Caco-2 cells and the possible regulatory mechanism. Methods Caco-2 cells expressing NHE3 were constructed and divided into four groups as follows control ( CTL ) group, RV group, BAPTA-AM ( a Ca2+ chelator) group and BAPTA-AM+RV group. Na+-H+ exchanger ac-tivity and NHE3 expression on cell surface were determined using BCECF-AM and biotinylation assay, re-spectively. Expression of Cdc42 at protein level was measured by Western blot. Results Compared with the control group, RV infection significantly decreased the activity of NHE3 and its expression on cell surface. BATPA-AM antagonized the inhibitory effects on NHE3. Moreover, the expression of Cdc42 at protein level was increased following RV infection, which was also antagonized by BATPA-AM. Conclusions Intracellu-lar Ca2+-mediated Cdc42-dependent endocytosis pathway might be involved in regulating the expression and bioactivity of NHE3 during RV infection.