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Updated: Jul 13, 2026

Utilizing pHluorin-tagged Receptors to Monitor Subcellular Localization and Trafficking
Published on: March 16, 2017
Rab11-FIP2 regulates differentiable steps in transcytosis
Nicole A Ducharme1, Janice A Williams, Asli Oztan
1Vanderbilt Univ. School of Medicine, Dept. of Surgery, Epithelial Biology Program, 4160A MRB III, 465 21st St. S., Nashville, TN 37232-2733, USA. jim.goldenring@vanderbilt.edu
Abstract:
Transcytosis through the apical recycling system of polarized cells is regulated by Rab11a and a series of Rab11a-interacting proteins. We have identified a point mutant in Rab11 family interacting protein 2 (Rab11-FIP2) that alters the function of Rab11a-containing trafficking systems. Rab11-FIP2(S229A/R413G) or Rab11-FIP2(R413G) cause the formation of a tubular cisternal structure containing Rab11a and decrease the rate of polymeric IgA transcytosis. The R413G mutation does not alter Rab11-FIP interactions with any known binding partners. Overexpression of Rab11-FIP2(S229A/R413G) alters the localization of a subpopulation of the apical membrane protein GP135. In contrast, Rab11-FIP2(129-512) alters the localization of early endosome protein EEA1. The distributions of both Rab11-FIP2(S229A/R413G) and Rab11-FIP2(129-512) were not dependent on the integrity of the microtubule cytoskeleton. The results indicate that Rab11-FIP2 regulates trafficking at multiple points within the apical recycling system of polarized cells.
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