E-Cadherin is a Ca2ϩ -dependent cell-cell adhesion molecule at adherens junctions (AJs) of epithelial cells. A fragment of N-cadherin lacking its extracellular region serves as a dominant negative mutant (DN) and inhibits cell-cell adhesion activity of E-cadherin, but its mode of action remains to be elucidated. Nectin is a Ca 2ϩ -independent immunoglobulin-like cell-cell adhesion molecule at AJs and is associated with E-cadherin through their respective peripheral membrane proteins, afadin and catenins, which connect nectin and cadherin to the actin cytoskeleton, respectively. We showed here that overexpression of nectin capable of binding afadin, but not a mutant incapable of binding afadin, reduced the inhibitory effect of N-cadherin DN on the cell-cell adhesion activity of E-cadherin in keratinocytes. Overexpressed nectin recruited N-cadherin DN to the nectin-based cell-cell adhesion sites in an afadin-dependent manner. Moreover, overexpression of nectin enhanced the E-cadherin-based cell-cell adhesion activity. These results suggest that N-cadherin DN competitively inhibits the association of the endogenous nectin-afadin system with the endogenous E-cadherin-catenin system and thereby reduces the cell-cell adhesion activity of E-cadherin. Thus, nectin plays a role in the formation of E-cadherin-based AJs in keratinocytes.
This paper presents a holographic technique for three-dimensional particle tracking. The complex amplitude on an image sensor is measured with two pairs of spatially phase-shifted digital holograms captured in a short time interval using a phase-shifting technique. Pairs of digital holograms are used to track small tracer particles in three-dimensional space and the phase-adjusted complex amplitude is employed in numerical image reconstruction to accurately detect the particles. The performance of the method is evaluated by numerical simulation. In order to demonstrate the feasibility of the method for real flow measurement, it is applied to the velocity measurement of tracer particles in a small water channel along which a high voltage is applied. The resulting components of the velocity vector in threedimensional space are compared to those obtained using a conventional single-shot phase-shifting technique.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.