Abstract

We propose to study the molecular basis of sorting of apical membrane proteins in polarized epithelial cells. We will do this by comparing and contrasting how two different epithelial cells types--the MDCK (kidney) and the WIF-B (hepatocyte) cells-- sequester and package two apical ectoenzymes. The first is dipeptidyl peptidase IV (DPPIV), belonging to the class of single transmembrane (Type II) proteins; and the second is 5' nucleotidase (5'NT), a glycolipid-anchored protein. Hepatocytes use an indirect, basolateral-to-apical transcytotic pathway(s) to deliver these proteins, while MDCK cells deliver them directly from the trans-Golgi network (TGN). However, when MDCK cells recover from prolonged treatment with the drug Brefeldin A, the retrieve missorted DPPIV and 5'NT from the basolateral surface and subsequently deliver them to the apical surface (ie, use the indirect route). The polymeric IgA-receptor (pIgA-R) normally uses a transcytotic pathway in both cell types. Do these proteins and cell types share a common (indirect) pathway? How similar or different are the indirect versus direct mechanisms for apical membrane targeting?

  Funding Agency

Agency
National Institute of Health (NIH)
Institute
National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
Type
Research Program Projects (P01)
Project #
5P01DK044375-10
Application #
6564273
Study Section
Project Start
2002-01-01
Project End
2002-12-31
Budget Start
Budget End
Support Year
10
Fiscal Year
2002
Total Cost
$146,667
Indirect Cost

  Institution

Name
Johns Hopkins University
Department
Type
DUNS #
045911138
City
Baltimore
State
MD
Country
United States
Zip Code
21218

  Publications

Suzuki, Kenichi G N; Fujiwara, Takahiro K; Edidin, Michael et al. (2007) Dynamic recruitment of phospholipase C gamma at transiently immobilized GPI-anchored receptor clusters induces IP3-Ca2+ signaling: single-molecule tracking study 2. J Cell Biol 177:731-42
Suzuki, Kenichi G N; Fujiwara, Takahiro K; Sanematsu, Fumiyuki et al. (2007) GPI-anchored receptor clusters transiently recruit Lyn and G alpha for temporary cluster immobilization and Lyn activation: single-molecule tracking study 1. J Cell Biol 177:717-30
Brown, Christa L; Maier, Kerstin C; Stauber, Tobias et al. (2005) Kinesin-2 is a motor for late endosomes and lysosomes. Traffic 6:1114-24
Berezuk, Matthew A; Schroer, Trina A (2004) Fractionation and characterization of kinesin II species in vertebrate brain. Traffic 5:503-13
Nyasae, Lydia K; Hubbard, Ann L; Tuma, Pamela L (2003) Transcytotic efflux from early endosomes is dependent on cholesterol and glycosphingolipids in polarized hepatic cells. Mol Biol Cell 14:2689-705
Tuma, Pamela L; Hubbard, Ann L (2003) Transcytosis: crossing cellular barriers. Physiol Rev 83:871-932
King, Stephen J; Brown, Christa L; Maier, Kerstin C et al. (2003) Analysis of the dynein-dynactin interaction in vitro and in vivo. Mol Biol Cell 14:5089-97
Tuma, Pamela L; Nyasae, Lydia K; Hubbard, Ann L (2002) Nonpolarized cells selectively sort apical proteins from cell surface to a novel compartment, but lack apical retention mechanisms. Mol Biol Cell 13:3400-15
Quintyne, Nicholas J; Schroer, Trina A (2002) Distinct cell cycle-dependent roles for dynactin and dynein at centrosomes. J Cell Biol 159:245-54
Bastaki, M; Braiterman, L T; Johns, D C et al. (2002) Absence of direct delivery for single transmembrane apical proteins or their ""Secretory"" forms in polarized hepatic cells. Mol Biol Cell 13:225-37

Showing the most recent 10 out of 36 publications