OPEN ACCESS ARTICLE

This Article Free via Open Access: OA OA Full Text Full Text (PDF) Supplemental Data OA All Versions of this Article: 148/1/223    most recent pp.108.120527v1 Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in Web of Science Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via CrossRef Citing Articles via Google Scholar Google Scholar Articles by Ma, L. Articles by Zhang, Z. Search for Related Content PubMed PubMed Citation Articles by Ma, L. Articles by Zhang, Z. Agricola Articles by Ma, L. Articles by Zhang, Z. Related Collections Membrane Trafficking

CELL BIOLOGY AND SIGNAL TRANSDUCTION

A Novel RNA-Binding Protein Associated with Cell Plate Formation^{1,[C],[W],[OA]}

State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430070, China (L.M., Z.Z.); College of Life Science, Yangtze University, Jingzhou 434025, China (L.M.); Department of Microbiology, Molecular Biology, and Biochemistry, University of Idaho, Moscow, Idaho 83844–3052 (B.X., Z.H.); and Department of Molecular Genetics and Plant Biotechnology Center, Ohio State University, Columbus, Ohio 43210–1002 (D.P.S.V.)

Building a cell plate during cytokinesis in plant cells requires the participation of a number of proteins in a multistep process. We previously identified phragmoplastin as a cell plate-specific protein involved in creating a tubulovesicular network at the cell plate. We report here the identification and characterization of a phragmoplastin-interacting protein, PHIP1, in Arabidopsis (Arabidopsis thaliana). It contains multiple functional motifs, including a lysine-rich domain, two RNA recognition motifs, and three CCHC-type zinc fingers. Polypeptides with similar motif structures were found only in plant protein databases, but not in the sequenced prokaryotic, fungal, and animal genomes, suggesting that PHIP1 represents a plant-specific RNA-binding protein. In addition to phragmoplastin, two Arabidopsis small GTP-binding proteins, Rop1 and Ran2, are also found to interact with PHIP1. The zinc fingers of PHIP1 were not required for its interaction with Rop1 and phragmoplastin, but they may participate in its binding with the Ran2 mRNA. Immunofluorescence, in situ RNA hybridization, and green fluorescent protein tagging experiments showed the association of PHIP1 with the forming cell plate during cytokinesis. Taken together, our data suggest that PHIP1 is a novel RNA-binding protein and may play a unique role in the polarized mRNA transport to the vicinity of the cell plate.

The authors responsible for distribution of materials integral to the findings presented in this article in accordance with the policy described in the Instructions for Authors (www.plantphysiol.org) are: Zhongming Zhang (zmzhang{at}mail.hzau.edu.cn) and Desh Pal S. Verma (verma.1{at}osu.edu).

^[C] Some figures in this article are displayed in color online but in black and white in the print edition.

^[W] The online version of this article contains Web-only data.

^[OA] Open Access articles can be viewed online without a subscription.

www.plantphysiol.org/cgi/doi/10.1104/pp.108.120527

^* Corresponding author; e-mail zmzhang{at}mail.hzau.edu.cn.

Received April 4, 2008; accepted July 7, 2008; published July 11, 2008.