Aminoaciduria and altered renal expression of luminal amino acid transporters in mice lacking novel gene collectrin.

Published

Journal Article

Defects in renal proximal tubule transport manifest in a number of human diseases. Although variable in clinical presentation, disorders such as Hartnup disease, Dent's disease, and Fanconi syndrome are characterized by wasting of solutes commonly recovered by the proximal tubule. One common feature of these disorders is aminoaciduria. There are distinct classes of amino acid transporters located in the apical and basal membranes of the proximal tubules that reabsorb >95% of filtered amino acids, yet few details are known about their regulation. We present our physiological characterization of a mouse line with targeted deletion of the gene collectrin that is highly expressed in the kidney. Collectrin-deficient mice display a reduced urinary concentrating capacity due to enhanced solute clearance resulting from profound aminoaciduria. The aminoaciduria is generalized, characterized by loss of nearly every amino acid, and results in marked crystalluria. Furthermore, in the kidney, collectrin-deficient mice have decreased plasma membrane populations of amino acid transporter subtypes B(0)AT1, rBAT, and b(0,+)AT, as well as altered cellular distribution of EAAC1. Our data suggest that collectrin is a novel mediator of renal amino acid transport and may provide further insight into the pathogenesis of a number of human disease correlates.

Full Text

Duke Authors

Cited Authors

  • Malakauskas, SM; Quan, H; Fields, TA; McCall, SJ; Yu, M-J; Kourany, WM; Frey, CW; Le, TH

Published Date

  • February 2007

Published In

Volume / Issue

  • 292 / 2

Start / End Page

  • F533 - F544

PubMed ID

  • 16985211

Pubmed Central ID

  • 16985211

International Standard Serial Number (ISSN)

  • 1931-857X

Digital Object Identifier (DOI)

  • 10.1152/ajprenal.00325.2006

Language

  • eng

Conference Location

  • United States