title: Arabidopsis dynamin-related protein 1A polymers bind, but do not tubulate, liposomes.
abstract: The Arabidopsis dynamin-related protein 1A (AtDRP1A) is involved in endocytosis and cell plate maturation in Arabidopsis. Unlike dynamin, AtDRP1A does not have any recognized membrane binding or protein-protein interaction domains. We report that GTPase active AtDRP1A purified from Escherichia coli as a fusion to maltose binding protein forms homopolymers visible by negative staining electron microscopy. These polymers interact with protein-free liposomes whose lipid composition mimics that of the inner leaflet of the Arabidopsis plasma membrane, suggesting that lipid-binding may play a role in AtDRP1A function. However, AtDRP1A polymers do not appear to assemble and disassemble in a dynamic fashion and do not have the ability to tubulate liposomes in vitro, suggesting that additional factors or modifications are necessary for AtDRP1A's in vivo function.
authors.affiliation: Department of Biochemistry, University of Wisconsin - Madison, 433 Babcock Dr., Madison, WI 53706, USA.
authors.forename: Steven K
authors.initials: SK
authors.lastname: Backues
authors.forename: Sebastian Y
authors.initials: SY
authors.lastname: Bednarek
mesh_terms: D017360:Arabidopsis / Q000201:enzymology*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D034281:Dynamins / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism; D008081:Liposomes / Q000378:metabolism; D011994:Recombinant Proteins / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism
chemical_list: D029681:Arabidopsis Proteins; D008081:Liposomes; D011994:Recombinant Proteins; C475162:ADL1A protein, Arabidopsis; D034281:Dynamins