Format

Send to

Choose Destination
Biochem Biophys Res Commun. 2008 Feb 29;367(1):60-6. Epub 2007 Dec 26.

A molecular modeling approach defines a new group of Nodulin 26-like aquaporins in plants.

Author information

1
Surfaces Cellulaires et Signalisation chez les Végétaux, UMR Université Paul Sabatier-CNRS 5546, 24 Chemin de Borde Rouge, 31326 Castanet Tolosan, France.

Abstract

The three-dimensional models built for the Nod26-like aquaporins all exhibit the typical alpha-helical fold of other aquaporins containing the two ar/R and NPA constriction filters along the central water channel. Besides these structural homologies, they readily differ with respect to the amino acid residues forming the ar/R selective filter. According to these discrepancies in both the hydrophilicity and pore size of the ar/R filter, Nod26-like aquaporins can be distributed in three subgroups corresponding to NIP-1, NIP-II and a third subgroup of Nod26-like aquaporins exhibiting a highly hydrophilic and widely open filter. However, all Nod26-like aquaporins display a bipartite distribution of electrostatic charges along the water channel with an electropositive extracellular vestibular portion followed by an electronegative cytosolic vestibular portion. The specific transport of water, non-ionic solutes (glycerol, urea, ammoniac), ions (NH4+) and gas (NH(3)) across the Nod26-like obviously depends on the electrostatic and conformational properties of their central water channel.

PMID:
18155659
DOI:
10.1016/j.bbrc.2007.12.079
[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for Elsevier Science
Loading ...
Support Center