Details

Autor(en) / Beteiligte

• Yamada, Soichiro
• Nelson, W. James

Titel

Localized Zones of Rho and Rac Activities Drive Initiation and Expansion of Epithelial Cell-Cell Adhesion

Ist Teil von

• The Journal of cell biology, 2007-07, Vol.178 (3), p.517-527

Ort / Verlag

United States: Rockefeller University Press

Erscheinungsjahr

2007

Quelle

MEDLINE

Beschreibungen/Notizen

• Spatiotemporal coordination of cell-cell adhesion involving lamellipodial interactions, cadherin engagement, and the lateral expansion of the contact is poorly understood. Using high-resolution live-cell imaging, biosensors, and small molecule inhibitors, we investigate how Racl and RhoA regulate actin dynamics during de novo contact formation between pairs of epithelial cells. Active Racl, the Arp2/3 complex, and lamellipodia are initially localized to de novo contacts but rapidly diminish as E-cadherin accumulates; further rounds of activation and down-regulation of Racl and Arp2/3 occur at the contacting membrane periphery, and this cycle repeats as a restricted membrane zone that moves outward with the expanding contact. The cortical bundle of actin filaments dissolves beneath the expanding contacts, leaving actin bundles at the contact edges. RhoA and actomyosin contractility are activated at the contact edges and are required to drive expansion and completion of cell-cell adhesion. We show that zones of Racl and lamellipodia activity and of RhoA and actomyosin contractility are restricted to the periphery of contacting membranes and together drive initiation, expansion, and completion of cell-cell adhesion.