About the Cover
On the Cover: Aquaporins are water channel proteins
that are found in the plasma membrane and the tonoplast, where they
increase the hydraulic permeability of the membrane. In companion articles, Chaumont et al. (pp. 1143-1152) and Barrieu et al. (pp. 1153-1163) describe the activity of a maize tonoplast aquaporin and
the expression pattern of the gene as determined by in situ hybridization. The expression patterns lead to the following
suggestions about the roles of aquaporins in plants: They function in
rapid osmotic equilibration between the cytoplasm and the vacuole, they are needed in cells that are exposed to sudden fluxes of ions or
metabolites, and they may play a role in the radial flow of water in
and out of the xylem vessels.
[Table of Contents]
Copyright © 2007 by the American Society of Plant Biologists
