Conserved tryptophans are required for adherens junction formation. (A) CHO cells stably expressing wild-type (mWT), W2A, and W4A mVE-cadherin, along with mock-transduced cells, were examined for the VE-cadherin clustering at adherens junctions by immunohistochemistry (mAb 15F12 + goat anti–rat-Cy3 IgG).