T. Sakisaka et al., Different behavior of l-afadin and Neurabin-II during the formation and destruction of cell-cell adherens junction, ONCOGENE, 18(8), 1999, pp. 1609-1617
We have recently isolated two novel actin filament-binding proteins, l-afad
in and neurabin-II and shown that they are localized at cell-cell adherens
junction (AJ) in epithelial cells. We found here that l-afadin, neurabin-II
, ZO-1, and E-cadherin showed similar and different behavior during the for
mation and destruction of cell-cell AJ in MDCK cells. In MDCK cells, the ac
cumulation of both l-afadin and E-cadherin, but not that of ZO-1, changed i
n parallel depending on Rac small G protein activity. Dissociation of MDCK
cells by culturing the cells at 2 mu M Ca2+ caused rapid endocytosis of E-c
adherin, but not that of l-afadin or ZO-1, Addition of phorbol 12-myristate
13-acetate to these dissociated cells formed a tight junction-like structu
re where ZO-1 and l-afadin, but not neurabin-II or E-cadherin, accumulated.
We furthermore found that, in nonepithelial EL cells, which expressed E-ca
dherin and attached to each other, l-afadin, neurabin-II, ZO-1 and E-cadher
in were all localized at AJ. In cadherin-deficient L cells, l-afadin was ma
inly localized at cell-cell contact sites, but ZO-1 was mainly localized at
the tip area of cell processes. Neurabin-II did not accumulate at the plas
ma membrane area. Neither l-afadin nor neurabin-II significantly interacted
with alpha-, beta-catenin, E-cadherin, ZO-1 or occludin.