Cell reproduction is a complex process involving whole cell structures and machineries in space and time, resulting in regulated distribution of endomembranes, organelles, and genomes between daughter cells. Secretory pathways supported by the activity of the Golgi apparatus play a crucial role in cytokinesis in plants. From the onset of phragmoplast initiation to the maturation of the cell plate, delivery of secretory vesicles is necessary to sustain successful daughter cell separation. Tethering of secretory vesicles at the plasma membrane is mediated by the evolutionarily conserved octameric exocyst complex. Using proteomic and cytologic approaches, we show that EXO84b is a subunit of the plant exocyst. Arabidopsis thaliana mutants for EXO84b are severely dwarfed and have compromised leaf epidermal cell and guard cell division. During cytokinesis, green fluorescent protein-tagged exocyst subunits SEC6, SEC8, SEC15b, EXO70A1, and EXO84b exhibit distinctive localization maxima at cell plate initiation and cell plate maturation, stages with a high demand for vesicle fusion. Finally, we present data indicating a defect in cell plate assembly in the exo70A1 mutant. We conclude that the exocyst complex is involved in secretory processes during cytokinesis in Arabidopsis cells, notably in cell plate initiation, cell plate maturation, and formation of new primary cell wall.

Institute of Experimental Botany Academy of Sciences of the Czech Republic 165 02 Prague 6 Czech Republic

Zobrazit více v PubMed

Abramoff M.D., Magelhaes P.J., Ram S.J. (2004). Image Processing with ImageJ. Biophotonics Int. 11: 36–42

Buschmann H., Chan J., Sanchez-Pulido L., Andrade-Navarro M.A., Doonan J.H., Lloyd C.W. (2006). Microtubule-associated AIR9 recognizes the cortical division site at preprophase and cell-plate insertion. Curr. Biol. 16: 1938–1943 PubMed

Chiu W., Niwa Y., Zeng W., Hirano T., Kobayashi H., Sheen J. (1996). Engineered GFP as a vital reporter in plants. Curr. Biol. 6: 325–330 PubMed

Chow C.M., Neto H., Foucart C., Moore I. (2008). Rab-A2 and Rab-A3 GTPases define a trans-Golgi endosomal membrane domain in PubMed PMC

Clough S.J., Bent A.F. (1998). Floral dip: A simplified method for PubMed

Cole R.A., Synek L., Žárský V., Fowler J.E. (2005). SEC8, a subunit of the putative PubMed PMC

Croteau N.J., Furgason M.L.M., Devos D., Munson M. (2009). Conservation of helical bundle structure between the exocyst subunits. PLoS ONE 4: e4443. PubMed PMC

Crowell E.F., Bischoff V., Desprez T., Rolland A., Stierhof Y.D., Schumacher K., Gonneau M., Höfte H., Vernhettes S. (2009). Pausing of Golgi bodies on microtubules regulates secretion of cellulose synthase complexes in PubMed PMC

Cutler S.R., Ehrhardt D.W. (2002). Polarized cytokinesis in vacuolate cells of PubMed PMC

Dong G., Hutagalung A.H., Fu C., Novick P., Reinisch K.M. (2005). The structures of exocyst subunit Exo70p and the Exo84p C-terminal domains reveal a common motif. Nat. Struct. Mol. Biol. 12: 1094–1100 PubMed

Eliáš M., Drdová E., Žiak D., Bavlnka B., Hála M., Cvrčková F., Soukupová H., Žárský V. (2003). The exocyst complex in plants. Cell Biol. Int. 27: 199–201 PubMed

Falbel T.G., Koch L.M., Nadeau J.A., Seguí-Simarro J.M., Sack F.D., Bednarek S.Y. (2003). SCD1 is required for cytokinesis and polarized cell expansion in PubMed

Fielding A.B., Schonteich E., Matheson J., Wilson G., Yu X., Hickson G.R.X., Srivastava S., Baldwin S.A., Prekeris R., Gould G.W. (2005). Rab11-FIP3 and FIP4 interact with Arf6 and the exocyst to control membrane traffic in cytokinesis. EMBO J. 24: 3389–3399 PubMed PMC

Finger F.P., Hughes T.E., Novick P. (1998). Sec3p is a spatial landmark for polarized secretion in budding yeast. Cell 92: 559–571 PubMed

Gromley A., Yeaman C., Rosa J., Redick S., Chen C.T., Mirabelle S., Guha M., Sillibourne J., Doxsey S.J. (2005). Centriolin anchoring of exocyst and SNARE complexes at the midbody is required for secretory-vesicle-mediated abscission. Cell 123: 75–87 PubMed

Grote E., Carr C.M., Novick P.J. (2000). Ordering the final events in yeast exocytosis. J. Cell Biol. 151: 439–452 PubMed PMC

Guo W., Grant A., Novick P. (1999a). Exo84p is an exocyst protein essential for secretion. J. Biol. Chem. 274: 23558–23564 PubMed

Guo W., Roth D., Walch-Solimena C., Novick P. (1999b). The exocyst is an effector for Sec4p, targeting secretory vesicles to sites of exocytosis. EMBO J. 18: 1071–1080 PubMed PMC

Guo W., Tamanoi F., Novick P. (2001). Spatial regulation of the exocyst complex by Rho1 GTPase. Nat. Cell Biol. 3: 353–360 PubMed

Gutierrez R., Lindeboom J.J., Paredez A.R., Emons A.M.C., Ehrhardt D.W. (2009). PubMed

Hála M., Cole R., Synek L., Drdová E., Pečenková T., Nordheim A., Lamkemeyer T., Madlung J., Hochholdinger F., Fowler J.E., Žárský V. (2008). An exocyst complex functions in plant cell growth in PubMed PMC

Hall Q., Cannon M.C. (2002). The cell wall hydroxyproline-rich glycoprotein RSH is essential for normal embryo development in PubMed PMC

Hamburger Z.A., Hamburger A.E., West A.P.J., Jr, Weis W.I. (2006). Crystal structure of the PubMed

Hazuka C.D., Foletti D.L., Hsu S.C., Kee Y., Hopf F.W., Scheller R.H. (1999). The sec6/8 complex is located at neurite outgrowth and axonal synapse-assembly domains. J. Neurosci. 19: 1324–1334 PubMed PMC

Heese M., Gansel X., Sticher L., Wick P., Grebe M., Granier F., Jürgens G. (2001). Functional characterization of the KNOLLE-interacting t-SNARE AtSNAP33 and its role in plant cytokinesis. J. Cell Biol. 155: 239–249 PubMed PMC

Hsu S.C., Hazuka C.D., Roth R., Foletti D.L., Heuser J., Scheller R.H. (1998). Subunit composition, protein interactions, and structures of the mammalian brain sec6/8 complex and septin filaments. Neuron 20: 1111–1122 PubMed

Jürgens G. (2005). Plant cytokinesis: Fission by fusion. Trends Cell Biol. 15: 277–283 PubMed

Karimi M., Inzé D., Depicker A. (2002). GATEWAY vectors for PubMed

Koumandou V.L., Dacks J.B., Coulson R.M.R., Field M.C. (2007). Control systems for membrane fusion in the ancestral eukaryote; evolution of tethering complexes and SM proteins. BMC Evol. Biol. 7: 29. PubMed PMC

Kulich I., Cole R., Drdová E., Cvrčková F., Soukup A., Fowler J., Žárský V. (2010). Arabidopsis exocyst subunits SEC8 and EXO70A1 and exocyst interactor ROH1 are involved in the localized deposition of seed coat pectin. New Phytol., in press PubMed

Lauber M.H., Waizenegger I., Steinmann T., Schwarz H., Mayer U., Hwang I., Lukowitz W., Jürgens G. (1997). The PubMed PMC

Lavy M., Bloch D., Hazak O., Gutman I., Poraty L., Sorek N., Sternberg H., Yalovsky S. (2007). A Novel ROP/RAC effector links cell polarity, root-meristem maintenance, and vesicle trafficking. Curr. Biol. 17: 947–952 PubMed

Martín-Cuadrado A.B., Morrell J.L., Konomi M., An H., Petit C., Osumi M., Balasubramanian M., Gould K.L., Del Rey F., de Aldana C.R.V. (2005). Role of septins and the exocyst complex in the function of hydrolytic enzymes responsible for fission yeast cell separation. Mol. Biol. Cell 16: 4867–4881 PubMed PMC

Matar D., Catesson A.M. (1988). Cell plate development and delayed formation of the pectic middle lamella in root meristems. Protoplasma 146: 10–17

Mineyuki Y., Gunning B. (1990). A role for preprophase bands of microtubules in maturation of new cell-walls, and a general proposal on the function of preprophase band sites in cell-division in higher-plants. J. Cell Sci. 97: 527–537

Moskalenko S., Tong C., Rosse C., Mirey G., Formstecher E., Daviet L., Camonis J., White M.A. (2003). Ral GTPases regulate exocyst assembly through dual subunit interactions. J. Biol. Chem. 278: 51743–51748 PubMed

Munson M., Novick P. (2006). The exocyst defrocked, a framework of rods revealed. Nat. Struct. Mol. Biol. 13: 577–581 PubMed

Nakagawa T., Kurose T., Hino T., Tanaka K., Kawamukai M., Niwa Y., Toyooka K., Matsuoka K., Jinbo T., Kimura T. (2007). Development of series of gateway binary vectors, pGWBs, for realizing efficient construction of fusion genes for plant transformation. J. Biosci. Bioeng. 104: 34–41 PubMed

Novick P., Field C., Schekman R. (1980). Identification of 23 complementation groups required for post-translational events in the yeast secretory pathway. Cell 21: 205–215 PubMed

Otegui M.S., Mastronarde D.N., Kang B.H., Bednarek S.Y., Staehelin L.A. (2001). Three-dimensional analysis of syncytial-type cell plates during endosperm cellularization visualized by high resolution electron tomography. Plant Cell 13: 2033–2051 PubMed PMC

Otegui M.S., Staehelin L.A. (2004). Electron tomographic analysis of post-meiotic cytokinesis during pollen development in PubMed

Otegui M.S., Verbrugghe K.J., Skop A.R. (2005). Midbodies and phragmoplasts: Analogous structures involved in cytokinesis. Trends Cell Biol. 15: 404–413 PubMed PMC

Reichelt S., Knight A.E., Hodge T.P., Baluška F., Šamaj J., Volkmann D., Kendrick-Jones J. (1999). Characterization of the unconventional myosin VIII in plant cells and its localization at the post-cytokinetic cell wall. Plant J. 19: 555–567 PubMed

Rosso M.G., Li Y., Strizhov N., Reiss B., Dekker K., Weisshaar B. (2003). An PubMed

Samuel M.A., Chong Y.T., Haasen K.E., Aldea-Brydges M.G., Stone S.L., Goring D.R. (2009). Cellular pathways regulating responses to compatible and self-incompatible pollen in PubMed PMC

Samuels A.L., Giddings T.H.J., Jr, Staehelin L.A. (1995). Cytokinesis in tobacco BY-2 and root tip cells: a new model of cell plate formation in higher plants. J. Cell Biol. 130: 1345–1357 PubMed PMC

Seguí-Simarro J.M., Austin J.R.I.I., II, White E.A., Staehelin L.A. (2004). Electron tomographic analysis of somatic cell plate formation in meristematic cells of PubMed PMC

Sessions A., et al. (2002). A high-throughput PubMed PMC

Sivaram M.V.S., Furgason M.L.M., Brewer D.N., Munson M. (2006). The structure of the exocyst subunit Sec6p defines a conserved architecture with diverse roles. Nat. Struct. Mol. Biol. 13: 555–556 PubMed

Smith T.J., Bell J.E. (1986). An exponential gradient marker for use with minigel polyacrylamide electrophoresis systems. Anal. Biochem. 152: 74–77 PubMed

Synek L., Schlager N., Eliáš M., Quentin M., Hauser M.T., Žárský V. (2006). AtEXO70A1, a member of a family of putative exocyst subunits specifically expanded in land plants, is important for polar growth and plant development. Plant J. 48: 54–72 PubMed PMC

TerBush D.R., Maurice T., Roth D., Novick P. (1996). The Exocyst is a multiprotein complex required for exocytosis in PubMed PMC

TerBush D.R., Novick P. (1995). Sec6, Sec8, and Sec15 are components of a multisubunit complex which localizes to small bud tips in PubMed PMC

Van Damme D., Coutuer S., De Rycke R., Bouget F.Y., Inzé D., Geelen D. (2006). Somatic cytokinesis and pollen maturation in PubMed PMC

Verma D.P. (2001). Cytokinesis and building of the cell plate in plants. Annu. Rev. Plant Physiol. Plant Mol. Biol. 52: 751–784 PubMed

Walker K.L., Müller S., Moss D., Ehrhardt D.W., Smith L.G. (2007). PubMed PMC

Wang H., Tang X., Liu J., Trautmann S., Balasundaram D., McCollum D., Balasubramanian M.K. (2002). The multiprotein exocyst complex is essential for cell separation in PubMed PMC

Wen T.J., Hochholdinger F., Sauer M., Bruce W., Schnable P.S. (2005). The PubMed PMC

Wu S., Mehta S.Q., Pichaud F., Bellen H.J., Quiocho F.A. (2005). Sec15 interacts with Rab11 via a novel domain and affects Rab11 localization in vivo. Nat. Struct. Mol. Biol. 12: 879–885 PubMed

Yang M., Nadeau J.A., Zhao L., Sack F.D. (1999). Characterization of a cytokinesis defective (cyd1) mutant of PubMed

Zajac A., Sun X., Zhang J., Guo W. (2005). Cyclical regulation of the exocyst and cell polarity determinants for polarized cell growth. Mol. Biol. Cell 16: 1500–1512 PubMed PMC

Žárský V., Cvrčková F., Potocký M., Hála M. (2009). Exocytosis and cell polarity in plants: Exocyst and recycling domains. New Phytol. 183: 255–272 PubMed

Zhang X., Bi E., Novick P., Du L., Kozminski K.G., Lipschutz J.H., Guo W. (2001). Cdc42 interacts with the exocyst and regulates polarized secretion. J. Biol. Chem. 276: 46745–46750 PubMed

Zhang X., Wang P., Gangar A., Zhang J., Brennwald P., TerBush D., Guo W. (2005a). Lethal giant larvae proteins interact with the exocyst complex and are involved in polarized exocytosis. J. Cell Biol. 170: 273–283 PubMed PMC

Zhang X., Zajac A., Zhang J., Wang P., Li M., Murray J., TerBush D., Guo W. (2005b). The critical role of Exo84p in the organization and polarized localization of the exocyst complex. J. Biol. Chem. 280: 20356–20364 PubMed

Exocyst subunits EXO70B1 and B2 contribute to stomatal dynamics and cell wall modifications

A Genome-Wide Association Screen for Genes Affecting Leaf Trichome Development and Epidermal Metal Accumulation in Arabidopsis

Automated Time-Lapse Imaging and Manipulation of Cell Divisions in Arabidopsis Roots by Vertical-Stage Confocal Microscopy

Plasma membrane phospholipid signature recruits the plant exocyst complex via the EXO70A1 subunit

Functional Specialization within the EXO70 Gene Family in Arabidopsis

EXO70A2 Is Critical for Exocyst Complex Function in Pollen Development

Synergy among Exocyst and SNARE Interactions Identifies a Functional Hierarchy in Secretion during Vegetative Growth

Redundant and Diversified Roles Among Selected Arabidopsis thaliana EXO70 Paralogs During Biotic Stress Responses

Regulation of Exocyst Function in Pollen Tube Growth by Phosphorylation of Exocyst Subunit EXO70C2

Developmental plasticity of Arabidopsis hypocotyl is dependent on exocyst complex function

EXO70C2 Is a Key Regulatory Factor for Optimal Tip Growth of Pollen

Analysis of Exocyst Subunit EXO70 Family Reveals Distinct Membrane Polar Domains in Tobacco Pollen Tubes

Exocyst SEC3 and Phosphoinositides Define Sites of Exocytosis in Pollen Tube Initiation and Growth

Tethering Complexes in the Arabidopsis Endomembrane System

Endosidin2 targets conserved exocyst complex subunit EXO70 to inhibit exocytosis

Cell wall maturation of Arabidopsis trichomes is dependent on exocyst subunit EXO70H4 and involves callose deposition

The exocyst at the interface between cytoskeleton and membranes in eukaryotic cells

Visualization of the exocyst complex dynamics at the plasma membrane of Arabidopsis thaliana

Formins: emerging players in the dynamic plant cell cortex

Evolution of the land plant exocyst complexes