title: MIZ1, an essential protein for root hydrotropism, is associated with the cytoplasmic face of the endoplasmic reticulum membrane in Arabidopsis root cells.
abstract: MIZ1 is encoded by a gene essential for root hydrotropism in Arabidopsis. To characterize the property of MIZ1, we used transgenic plants expressing GFP-tagged MIZ1 (MIZ1-GFP) and mutant MIZ1 (MIZ1(G235E)-GFP) in a miz1-1 mutant. Although both chimeric genes were transcribed, the translational products of MIZ1(G235E)-GFP did not accumulate in roots. Moreover, MIZ1-GFP complemented the mutant phenotype but not MIZ1(G235E)-GFP. The signal corresponding to MIZ1-GFP was detected at high levels in cortical cells and lateral root cap cells and accumulated in compartments in cortical cells. MIZ1-GFP was fractionated into a soluble protein fraction and an endoplasmic reticulum (ER) membrane fraction, where it was bound to the surface of the ER membrane at the cytosolic side.
authors.affiliation: Graduate School of Life Sciences, Tohoku University, Sendai, Miyagi, Japan. yamat@ige.tohoku.ac.jp
authors.forename: Tomokazu
authors.initials: T
authors.lastname: Yamazaki
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Miyazawa
authors.forename: Akie
authors.initials: A
authors.lastname: Kobayashi
authors.forename: Teppei
authors.initials: T
authors.lastname: Moriwaki
authors.forename: Nobuharu
authors.initials: N
authors.lastname: Fujii
authors.forename: Hideyuki
authors.initials: H
authors.lastname: Takahashi
mesh_terms: D019943:Amino Acid Substitution; D017360:Arabidopsis / Q000235:genetics / Q000254:growth & development* / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D001483:Base Sequence; D018744:DNA, Plant / Q000235:genetics; D004721:Endoplasmic Reticulum / Q000378:metabolism; D017343:Genes, Plant; D049452:Green Fluorescent Proteins / Q000235:genetics; D007425:Intracellular Membranes / Q000378:metabolism; D020125:Mutation, Missense; D018517:Plant Roots / Q000166:cytology / Q000254:growth & development / Q000378:metabolism; D030821:Plants, Genetically Modified
chemical_list: D029681:Arabidopsis Proteins; D018744:DNA, Plant; C519512:mizu-kussei1 protein, Arabidopsis; D049452:Green Fluorescent Proteins