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A molecular network for de novo generation of the apical surface and lumen.

ABSTRACT: To form epithelial organs cells must polarize and generate de novo an apical domain and lumen. Epithelial polarization is regulated by polarity complexes that are hypothesized to direct downstream events, such as polarized membrane traffic, although this interconnection is not well understood. We have found that Rab11a regulates apical traffic and lumen formation through the Rab guanine nucleotide exchange factor (GEF), Rabin8, and its target, Rab8a. Rab8a and Rab11a function through the exocyst to target Par3 to the apical surface, and control apical Cdc42 activation through the Cdc42 GEF, Tuba. These components assemble at a transient apical membrane initiation site to form the lumen. This Rab11a-directed network directs Cdc42-dependent apical exocytosis during lumen formation, revealing an interaction between the machineries of vesicular transport and polarization.

SUBMITTER: Bryant DM

PROVIDER: S-EPMC2975675 | biostudies-literature | 2010 Nov

REPOSITORIES: biostudies-literature

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A molecular network for de novo generation of the apical surface and lumen.

Bryant David M DM Datta Anirban A Rodríguez-Fraticelli Alejo E AE Peränen Johan J Martín-Belmonte Fernando F Mostov Keith E KE

Nature cell biology 20101003 11

To form epithelial organs cells must polarize and generate de novo an apical domain and lumen. Epithelial polarization is regulated by polarity complexes that are hypothesized to direct downstream events, such as polarized membrane traffic, although this interconnection is not well understood. We have found that Rab11a regulates apical traffic and lumen formation through the Rab guanine nucleotide exchange factor (GEF), Rabin8, and its target, Rab8a. Rab8a and Rab11a function through the exocyst ...[more]

PMID: 20890297

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