Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
2005-7-8
pubmed:abstractText
Aquaporins (AQPs) accelerate the movement of water and other solutes across biological membranes, yet the molecular mechanisms of each AQP's transport function and the diverse physiological roles played by AQP family members are still being defined. We therefore have characterized an AQP in a model organism, Drosophila melanogaster, which is amenable to genetic manipulation and developmental analysis. To study the mechanism of Drosophila Malpighian tubule (MT)-facilitated water transport, we identified seven putative AQPs in the Drosophila genome and found that one of these, previously named DRIP, has the greatest sequence similarity to those vertebrate AQPs that exhibit the highest rates of water transport. In situ mRNA analyses showed that DRIP is expressed in both embryonic and adult MTs, as well as in other tissues in which fluid transport is essential. In addition, the pattern of DRIP expression was dynamic. To define DRIP-mediated water transport, the protein was expressed in Xenopus oocytes and in yeast secretory vesicles, and we found that significantly elevated rates of water transport correlated with DRIP expression. Moreover, the activation energy required for water transport in DRIP-expressing secretory vesicles was 4.9 kcal/mol. This low value is characteristic of AQP-mediated water transport, whereas the value in control vesicles was 16.4 kcal/mol. In contrast, glycerol, urea, ammonia, and proton transport were unaffected by DRIP expression, suggesting that DRIP is a highly selective water-specific channel. This result is consistent with the homology between DRIP and mammalian water-specific AQPs. Together, these data establish Drosophila as a new model system with which to investigate AQP function.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
0363-6143
pubmed:author
pubmed:issnType
Print
pubmed:volume
289
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
C397-407
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
2005
pubmed:articleTitle
Developmental expression and biophysical characterization of a Drosophila melanogaster aquaporin.
pubmed:affiliation
Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA 15260, USA.
pubmed:publicationType
Journal Article, Comparative Study, Research Support, U.S. Gov't, P.H.S., Research Support, N.I.H., Extramural