title: Mediation of clathrin-dependent trafficking during cytokinesis and cell expansion by Arabidopsis stomatal cytokinesis defective proteins.
abstract: Stomatal cytokinesis defective1 (SCD1) encodes a putative Rab guanine nucleotide exchange factor that functions in membrane trafficking and is required for cytokinesis and cell expansion in Arabidopsis thaliana. Here, we show that the loss of SCD2 function disrupts cytokinesis and cell expansion and impairs fertility, phenotypes similar to those observed for scd1 mutants. Genetic and biochemical analyses showed that SCD1 function is dependent upon SCD2 and that together these proteins are required for plasma membrane internalization. Further specifying the role of these proteins in membrane trafficking, SCD1 and SCD2 proteins were found to be associated with isolated clathrin-coated vesicles and to colocalize with clathrin light chain at putative sites of endocytosis at the plasma membrane. Together, these data suggest that SCD1 and SCD2 function in clathrin-mediated membrane transport, including plasma membrane endocytosis, required for cytokinesis and cell expansion.
authors.affiliation: Department of Biochemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706.
authors.forename: Colleen M
authors.initials: CM
authors.lastname: McMichael
authors.forename: Gregory D
authors.initials: GD
authors.lastname: Reynolds
authors.forename: Lisa M
authors.initials: LM
authors.lastname: Koch
authors.forename: Chao
authors.initials: C
authors.lastname: Wang
authors.forename: Nan
authors.initials: N
authors.lastname: Jiang
authors.forename: Jeanette
authors.initials: J
authors.lastname: Nadeau
authors.forename: Fred D
authors.initials: FD
authors.lastname: Sack
authors.forename: Max B
authors.initials: MB
authors.lastname: Gelderman
authors.forename: Jianwei
authors.initials: J
authors.lastname: Pan
authors.forename: Sebastian Y
authors.initials: SY
authors.lastname: Bednarek
mesh_terms: D017360:Arabidopsis / Q000166:cytology* / Q000235:genetics; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D002462:Cell Membrane / Q000378:metabolism; D002966:Clathrin / Q000378:metabolism*; D022163:Clathrin-Coated Vesicles / Q000378:metabolism; D048749:Cytokinesis; D004705:Endocytosis; D008969:Molecular Sequence Data; D009154:Mutation; D030821:Plants, Genetically Modified / Q000166:cytology / Q000235:genetics
chemical_list: D029681:Arabidopsis Proteins; D002966:Clathrin