title: Rab11-FIP1A regulates early trafficking into the recycling endosomes.
abstract: The Rab11 family of small GTPases, along with the Rab11-family interacting proteins (Rab11-FIPs), are critical regulators of intracellular vesicle trafficking and recycling. We have identified a point mutation of Threonine-197 site to an Alanine in Rab11-FIP1A, which causes a dramatic dominant negative phenotype when expressed in HeLa cells. The normally perinuclear distribution of GFP-Rab11-FIP1A was condensed into a membranous cisternum with almost no GFP-Rab11-FIP1A(T197A) remaining outside of this central locus. Also, this condensed GFP-FIP1A(T197A) altered the distribution of proteins in the Rab11a recycling pathway including endogenous Rab11a, Rab11-FIP1C, and transferrin receptor (CD71). Furthermore, this condensed GFP-FIP1A(T197A)-containing structure exhibited little movement in live HeLa cells. Expression of GFP-FIP1A(T197A) caused a strong blockade of transferrin recycling. Treatment of cells expressing GFP-FIP1A(T197A) with nocodazole did not disperse the Rab11a-containing recycling system. We also found that Rab5 and EEA1 were accumulated in membranes by GFP-Rab11-FIP1A but Rab4 was unaffected, suggesting that a direct pathway may exist from early endosomes into the Rab11a-containing recycling system. Our study of a potent inhibitory trafficking mutation in Rab11-FIP1A shows that Rab11-FIP1A associates with and regulates trafficking at an early step in the process of membrane recycling.
authors.affiliation: Departments of Surgery, Nashville, TN, USA; Epithelial Biology Center, Nashville, TN, USA.
authors.forename: Jenny C
authors.initials: JC
authors.lastname: Schafer
authors.affiliation: Departments of Surgery, Nashville, TN, USA; Cell & Developmental Biology, Nashville, TN, USA; Epithelial Biology Center, Nashville, TN, USA.
authors.forename: Rebecca E
authors.initials: RE
authors.lastname: McRae
authors.affiliation: Departments of Surgery, Nashville, TN, USA; Epithelial Biology Center, Nashville, TN, USA.
authors.forename: Elizabeth H
authors.initials: EH
authors.lastname: Manning
authors.affiliation: Departments of Surgery, Nashville, TN, USA; Epithelial Biology Center, Nashville, TN, USA.
authors.forename: Lynne A
authors.initials: LA
authors.lastname: Lapierre
authors.affiliation: Departments of Surgery, Nashville, TN, USA; Cell & Developmental Biology, Nashville, TN, USA; Epithelial Biology Center, Nashville, TN, USA; Vanderbilt University School of Medicine and the Nashville VA Medical Center, Nashville, TN, USA. Electronic address: jim.goldenring@vanderbilt.edu.
authors.forename: James R
authors.initials: JR
authors.lastname: Goldenring
mesh_terms: D002462:Cell Membrane / Q000378:metabolism; D011992:Endosomes / Q000378:metabolism*; D049452:Green Fluorescent Proteins / Q000378:metabolism; D006367:HeLa Cells; D006801:Humans; D008565:Membrane Proteins / Q000378:metabolism; D011485:Protein Binding; D021381:Protein Transport; D014168:Transferrin / Q000378:metabolism*; D020691:rab GTP-Binding Proteins / Q000378:metabolism*; D000099193:rab11 GTP-Binding Proteins
chemical_list: D049452:Green Fluorescent Proteins; D008565:Membrane Proteins; D014168:Transferrin; D020691:rab GTP-Binding Proteins; D000099193:rab11 GTP-Binding Proteins
keywords: EEA1; Endocytosis; Membrane recycling; Rab11; Rab11-FIP1; Rab11-FIP2; Rab11-FIP5; Rab11a; Rab14; Rab4; Rab5; Rab8a