Calcium-dependent dynamics of cadherin interactions at cell-cell junctions.
Proc Natl Acad Sci U S A
; 108(24): 9857-62, 2011 Jun 14.
Article
em En
| MEDLINE
| ID: mdl-21613566
ABSTRACT
Cadherins play a key role in the dynamics of cell-cell contact formation and remodeling of junctions and tissues. Cadherin-cadherin interactions are gated by extracellular Ca(2+), which serves to rigidify the cadherin extracellular domains and promote trans junctional interactions. Here we describe the direct visualization and quantification of spatiotemporal dynamics of N-cadherin interactions across intercellular junctions in living cells using a genetically encodable FRET reporter system. Direct measurements of transjunctional cadherin interactions revealed a sudden, but partial, loss of homophilic interactions (τ = 1.17 ± 0.06 s(-1)) upon chelation of extracellular Ca(2+). A cadherin mutant with reduced adhesive activity (W2A) exhibited a faster, more substantial loss of homophilic interactions (τ = 0.86 ± 0.02 s(-1)), suggesting two types of native cadherin interactions--one that is rapidly modulated by changes in extracellular Ca(2+) and another with relatively stable adhesive activity that is Ca(2+) independent. The Ca(2+)-sensitive dynamics of cadherin interactions were transmitted to the cell interior where ß-catenin translocated to N-cadherin at the junction in both cells. These data indicate that cadherins can rapidly convey dynamic information about the extracellular environment to both cells that comprise a junction.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Caderinas
/
Cálcio
/
Beta Catenina
/
Junções Intercelulares
Limite:
Animals
/
Humans
Idioma:
En
Ano de publicação:
2011
Tipo de documento:
Article