We hypothesize that Bves, by regulating TJ formation, may play a role in modulating RhoA signaling and the state of MLC phosphorylation in TM cells (
Fig. 1). In this study, we have demonstrated the presence of endogenous Bves in TM tissues and cultured human TM cells (
Fig. 2). Increased expression of Bves appears to lead to decreased levels of MLC-p (
Fig. 8), which suggests that Bves plays a regulatory role in TM cells. Because overexpression of Bves leads to increased TJ formation in TM cells, this likely has a direct effect on the signaling role of TJs in TM cells. In this study, increased TJ formation was confirmed biochemically through the detection of increased levels of occludin message and protein (
Fig. 4). In addition, cell culture–based assays for TJ function, transcellular passage of fluorescein, and electrical resistance further verified increased TJ formation with Bves overexpression in TM cells (
Fig. 5). These findings indicate that Bves regulates TJ formation in TM cells, as was observed in human corneal epithelial cells.
13–15 Because TJs have been shown to play a role in modulating RhoA activation,
19,31,32 changes in the state of RhoA activation were evaluated in TM cells transiently overexpressing Bves. These cells exhibited decreased RhoA activation (
Fig. 7). In addition, increased Bves expression is associated with decreased levels of MLC-p (
Fig. 8), an end point target in the RhoA signaling pathway in TM.
7 These findings indicate that Bves plays a role in regulating TJ formation in TM cells, with subsequent modulation of RhoA signaling.