QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

Vol. 17, Issue 10, 4318-4329, October 2006

This Article Full Text Full Text (PDF) Supplemental Material All Versions of this Article: E06-01-0035v1 17/10/4318    most recent Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Larsen, M. K. Articles by Knudsen, J. Search for Related Content PubMed PubMed Citation Articles by Larsen, M. K. Articles by Knudsen, J.

MAA-1, a Novel Acyl-CoA–binding Protein Involved in Endosomal Vesicle Transport in Caenorhabditis elegans

Morten K. Larsen^*,, Simon Tuck, Nils J. Færgeman^*, and Jens Knudsen^*

*Department of Biochemistry and Molecular Biology, University of Southern Denmark, 5230 Odense M, Denmark; and Umeå Center for Molecular Pathogenesis, Umeå University, Umeå, SE-90187, Sweden

Submitted January 13, 2006; Revised July 13, 2006; Accepted July 17, 2006
Monitoring Editor: Benjamin Glick

The budding and fission of vesicles during membrane trafficking requires many proteins, including those that coat the vesicles, adaptor proteins that recruit components of the coat, and small GTPases that initiate vesicle formation. In addition, vesicle formation in vitro is promoted by the hydrolysis of acyl-CoA lipid esters. The mechanisms by which these lipid esters are directed to the appropriate membranes in vivo, and their precise roles in vesicle biogenesis, are not yet understood. Here, we present the first report on membrane associated ACBP domain-containing protein-1 (MAA-1), a novel membrane-associated member of the acyl-CoA–binding protein family. We show that in Caenorhabditis elegans, MAA-1 localizes to intracellular membrane organelles in the secretory and endocytic pathway and that mutations in maa-1 reduce the rate of endosomal recycling. A lack of maa-1 activity causes a change in endosomal morphology. Although in wild type, many endosomal organelles have long tubular protrusions, loss of MAA-1 activity results in loss of the tubular domains, suggesting the maa-1 is required for the generation or maintenance of these domains. Furthermore, we demonstrate that MAA-1 binds fatty acyl-CoA in vitro and that this ligand-binding ability is important for its function in vivo. Our results are consistent with a role for MAA-1 in an acyl-CoA–dependent process during vesicle formation.

This article was published online ahead of print in MBC in Press (http://www.molbiolcell.org/cgi/doi/10.1091/mbc.E06-01-0035) on July 26, 2006.

Address correspondence to: Simon Tuck (simon.tuck{at}ucmp.umu.se) or Jens Knudsen (jkk{at}bmb.sdu.dk)