From genome to function: the Arabidopsis aquaporins.
BACKGROUND
In the post-genomic era newly sequenced genomes can be used to deduce organismal functions from our knowledge of other systems. Here we apply this approach to analyzing the aquaporin gene family in Arabidopsis thaliana. The aquaporins are intrinsic membrane proteins that have been characterized as facilitators of water flux. Originally termed major intrinsic proteins (MIPs), they are now also known as water channels, glycerol facilitators and aqua-glyceroporins, yet recent data suggest that they facilitate the movement of other low-molecular-weight metabolites as well.


RESULTS
The Arabidopsis genome contains 38 sequences with homology to aquaporin in four subfamilies, termed PIP, TIP, NIP and SIP. We have analyzed aquaporin family structure and expression using the A. thaliana genome sequence, and introduce a new NMR approach for the purpose of analyzing water movement in plant roots in vivo.


CONCLUSIONS
Our preliminary data indicate a strongly transcellular component for the flux of water in roots.
Quigley
Francoise
F
Department of Biochemistry and Molecular Biophysics, University of Arizona, Tucson, AZ 85721, USA. bohnerth@life.uiuc.edu
Rosenberg
Joshua M
JM
Shachar-Hill
Yair
Y
Bohnert
Hans J
HJ
D000595:Amino Acid Sequence; D020346:Aquaporins / Q000737:chemistry / Q000235:genetics* / Q000502:physiology; D017360:Arabidopsis / Q000235:genetics* / Q000502:physiology; D001692:Biological Transport; D017343:Genes, Plant / Q000235:genetics; D018745:Genome, Plant; D009682:Magnetic Resonance Spectroscopy; D008954:Models, Biological; D008969:Molecular Sequence Data; D015394:Molecular Structure; D010802:Phylogeny; D014867:Water / Q000378:metabolism
D020346:Aquaporins; D014867:Water