Heterocellular interaction enhances recruitment of {alpha} and {beta}-catenins and ZO-2 into functional gap-junction complexes and induces gap junction-dependant differentiation of mammary epithelial cells

Journal Article · Sat Nov 01 04:00:00 EDT 2008 · Experimental Cell Research

DOI:https://doi.org/10.1016/j.yexcr.2008.07.030· OSTI ID:21176135

Mroue, Rana; Mokalled, Mayssa; Abi-Mosleh, Lina; Nehme, Ralda; Ismail, Ayman; Khalil, Antoine ^[1]; Zaatari, Mira ^[2]

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1. Department of Biology, Faculty of Arts and Sciences, American University of Beirut, Beirut (Lebanon)
2. Department of Human Morphology, Faculty of Medicine, American University of Beirut, Beirut (Lebanon)

Gap junctions (GJ) are required for mammary epithelial differentiation. Using epithelial (SCp2) and myoepithelial-like (SCg6) mouse-derived mammary cells, the role of heterocellular interaction in assembly of GJ complexes and functional differentiation ({beta}-casein expression) was evaluated. Heterocellular interaction is critical for {beta}-casein expression, independent of exogenous basement membrane or cell anchoring substrata. Functional differentiation of SCp2, co-cultured with SCg6, is more sensitive to GJ inhibition relative to homocellular SCp2 cultures differentiated by exogenous basement membrane. Connexin (Cx)32 and Cx43 levels were not regulated across culture conditions; however, GJ functionality was enhanced under differentiation-permissive conditions. Immunoprecipitation studies demonstrated association of junctional complex components ({alpha}-catenin, {beta}-catenin and ZO-2) with Cx32 and Cx43, in differentiation conditions, and additionally with Cx30 in heterocellular cultures. Although {beta}-catenin did not shuttle between cadherin and GJ complexes, increased association between connexins and {beta}-catenin in heterocellular cultures was observed. This was concomitant with reduced nuclear {beta}-catenin, suggesting that differentiation in heterocellular cultures involves sequestration of {beta}-catenin in GJ complexes.

• OSTI ID: 21176135
• Journal Information: Experimental Cell Research, Journal Name: Experimental Cell Research Journal Issue: 18 Vol. 314; ISSN 0014-4827; ISSN ECREAL
• Country of Publication: United States
• Language: English

Related Subjects

60 APPLIED LIFE SCIENCES
CASEIN
CELL MEMBRANES
COMPLEXES
INHIBITION
INTERACTIONS
LACTATION
MICE
RABBIT TUBES