Plant Cell Monogr (9)
D.P.S. Verma and Z. Hong: Cell Division Control in Plants
DOI 10.1007/7089_2007_132/Published online: 26 July 2007
©Springer-Verlag Berlin Heidelberg 2007
Vesicle Traffic at Cytokinesis
Anton Sanderfoot
Department of Plant Biology, University of Minnesota-Twin Cities,
250 Biological Sciences Center, 1445 Gortner Ave, Saint Paul, MN 55108, USA
[email protected]
AbstractCytokinesis, the mechanical process by which one cell becomes two, is essential
to all life, be it single-celled bacteria or complex multicellular organisms like land plants
or animals. It is now clear that new membrane must be added to the mother cell to ac-
complishthecompleteenclosureofthetwodaughters.Inlandplants,thisisespecially
apparent because they accomplish cytokinesis with the cell plate, a structure newly as-
sembled by addition of new membrane vesicles. This review will focus on what we know
about the source of the vesicles that make up the cell plate membrane, the molecular ma-
chinery involved in assembling those vesicles, and just what those vesicles are carrying to
the cell plate.
1
Making Two Cells from One
Cytokinesis is essential to the propagation of all life, be it single-celled bac-
teria or complex multicellular organisms like land plants or animals. Funda-
mentally, the binary fission of bacteria is analogous to the morphologically
complex cell-plate mediated division of the land plants, since each accom-
plishes the division of the cytosol by addition of new membrane between the
two daughters. The only difference being that the membrane is derived from
the “outside-in” movement of the plasma membrane (PM) during binary fis-
sion (e.g. the “cleavage furrow”), while the cell plate is considered to function
in an “insideout” movement of the expanding nascent cell plate towards the
membrane (though see Cutler and Ehrhardt 2003). As more is learned about
these processes in each kind of organism, the “analogy” becomes more re-
placed by “homology”, at least in terms of the role of the vesicle trafficking
machinery in the eukaryotic processes of cytokinesis.
It is in the land plants that one can most easily observe the role of vesi-
cle trafficking in cell division, since the cell plate is obviously constructed by
fusion of vesicles derived from the secretory pathway (Jürgens 2005). How-
ever, based on both mathematics and biochemistry, new membrane must be
added in all forms of cytokinesis. For example, volume (i.e. the cell contents)
scales with the cube of the radius, while surface area (i.e. the membrane) scales
with the square. Basically, assuming that the mother cell gives each daughter
half the cell volume, half of the surface area of the mother cell is not suffi-