Welcome to biology-online.org! Please login to access all site features. Create an account.
Log me on automatically each visit
Aquaglyceroporins form the subset of the aquaporin water channel family that is …
Biology Articles » Biochemistry » Protein Biochemistry » Aquaglyceroporin AQP9: Solute permeation and metabolic control of expression in liver
The physiological functions of AQP9 are uncertain. During prolonged fasting, glycerol released from adipocytes via AQP7 may be taken up by the liver via AQP9 for gluconeogenesis. Urea, a byproduct of amino acid deamination, and β-hydroxybutyrate, an alternative fuel, may be released from liver via AQP9. An elegant series of recent studies of adipocyte AQP7 and liver AQP9 mRNAs and promoters suggested that the genes are coordinately regulated during fasting and type 1 diabetes mellitus (9), but this has not been confirmed with studies of the AQP7 and AQP9 proteins.
We undertook studies to define the permeation of proteoliposomes reconstituted with purified rat AQP9 protein and to provide evidence that expression of AQP9 protein is altered in rats during fasting and insulin deficiency. Our studies indicate that AQP9 facilitates hepatocyte glycerol influx and urea efflux, establishing a greater functional repertoire for AQP9 as a solute channel with minor water transport capacity.
rating: 0.00 from 0 votes | updated on: 7 Feb 2009 | views: 4971 |
share this article | email to friends
suggest a revision
print this page
print the whole article
© Biology-Online.org. All Rights Reserved. Register | Login | About Us | Contact Us | Link to Us | Disclaimer & Privacy