Cadherin-mediated regulation of microtubule dynamics. A. Chausovsky, A.D. Bershadsky and G.G. Borisy Nat Cell Biol. 2000 Nov; 2(11):797-804

Epithelial polarization and neuronal outgrowth require the assembly of microtubule (MT) arrays not associated with centrosomes. Since these processes generally involve contact interactions mediated by cadherins, we investigated the potential role of cadherin signaling in the stabilization of non-centrosomal MTs. We analyzed MT organization and dynamics in cytoplasts prepared from CHO cells (which normally do not express cadherins) and transfectants of them stably expressing either N- or E-cadherin. Cadherin expression in centrosome-free cytoplasts increased MT polymer level and changed the behavior of MTs from treadmilling to dynamic instability. This effect was not a result of cadherin expression per se but depended on formation of cell-cell contacts. The effect of cell-cell contacts was mimicked by application of beads coated with stimulatory cadherin antibody and was suppressed by overexpression of the cytoplasmic cadherin tail. We suggest that cadherins initiate a signaling pathway which alters MT organization by stabilizing MT ends.

	Figure 1 ( K) - Cadherin expression in CHO cells
	Figure 2 ( K) - Effect of cadherin expression and cell-cell contacts in centrosome-free cytoplasts
	Figure 3 ( K) - Quantification of MT fluorescence in isolated and contacting cytoplasts
	Figure 4 ( K) - MT organization and dynamics in isolated and contacting cytoplasts
	Figure 5 ( K) - Effect of N-cadherin-inhibitory antibody (AB) on integrity of adherens junctions and MT organization
	Figure 6 ( K) - Effect of N-cadherin-stimulatory beads on MT organization
	Figure 7 ( K) - Effect of cytoplasmic N-cadherin tail overexpression on MT organization in contacting N-cadherin expressing cytoplasts