HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

J. Biol. Chem., Vol. 282, Issue 41, 30207-30215, October 12, 2007

This Article Full Text Full Text (PDF) Supplemental Data All Versions of this Article: 282/41/30207    most recent M702639200v1 Submit a Letter to Editor Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Permissions Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Echevarría, M. Articles by López-Barneo, J. Search for Related Content PubMed PubMed Citation Articles by Echevarría, M. Articles by López-Barneo, J. Social Bookmarking                      What's this?

Development of Cytosolic Hypoxia and Hypoxia-inducible Factor Stabilization Are Facilitated by Aquaporin-1 Expression^*

From the Laboratorio de Investigaciones Biomédicas, Departamento de Fisiología Médica y Biofísica, Hospital Universitario Virgen del Rocío, Universidad de Sevilla, Sevilla, 41013 Spain

O₂ is essential for aerobic life, and the classic view is that it diffuses freely across the plasma membrane. However, measurements of O₂ permeability of lipid bilayers have indicated that it is much lower than previously thought, and therefore, the existence of membrane O₂ channels has been suggested. We hypothesized that, besides its role as a water channel, aquaporin-1 (AQP-1) could also work as an O₂ transporter, because this transmembrane protein appears to be CO₂-permeable and is highly expressed in cells with rapid O₂ turnover (erythrocytes and microvessel endothelium). Here we show that in mammalian cells overexpressing AQP-1 and exposed to hypoxia, the loss of cytosolic O₂, as well as stabilization of the O₂-dependent hypoxia-inducible transcription factor and expression of its target genes, is accelerated. In normoxic endothelial cells, knocking down AQP-1 produces induction of hypoxia-inducible genes. Moreover, lung AQP-1 is markedly up-regulated in animals exposed to hypoxia. These data suggest that AQP-1 has O₂ permeability and thus could facilitate O₂ diffusion across the cell membrane.

Received for publication, March 27, 2007 , and in revised form, July 31, 2007.

^* This work was funded in part by Ayuda a la Investigación 2000 of the Juan March Foundation and by grants from the Instituto de Salud Carlos III PI 030296 and Consejería de Salud, Junta de Andalucía, 22/02. The costs of publication of this article were defrayed in part by the payment of page charges. This article must therefore be hereby marked "advertisement" in accordance with 18 U.S.C. Section 1734 solely to indicate this fact.

The on-line version of this article (available at http://www.jbc.org) contains supplemental Fig. 1.

¹ Both authors contributed equally to this work.

² Supported by a predoctoral fellowship from the Spanish Ministries of Health and of Education.

³ To whom correspondence should be addressed: Laboratorio de Investigaciones Biomédicas, Edificio de Laboratorios, 2 planta, Hospital Universitario Virgen del Rocío, Avenida Manuel Siurot s/n, 41013 Sevilla, Spain. Tel.: 34-955-012648; Fax: 34-954-617301; E-mail: lbarneo{at}us.es.

CiteULike    Complore    Connotea    Del.icio.us    Digg    Reddit    Technorati    What's this?

This article has been cited by other articles:

				K.-H. Han, K. Mekala, V. Babida, H.-Y. Kim, M. E. Handlogten, J. W. Verlander, and I. D. Weiner Expression of the gas-transporting proteins, Rh B glycoprotein and Rh C glycoprotein, in the murine lung Am J Physiol Lung Cell Mol Physiol, July 1, 2009; 297(1): L153 - L163. [Abstract] [Full Text] [PDF]

				A. C. N. Brown, D. Hallouane, W. J. Mawby, F. E. Karet, M. A. Saleem, A. J. Howie, and A. M. Toye RhCG is the major putative ammonia transporter expressed in the human kidney, and RhBG is not expressed at detectable levels Am J Physiol Renal Physiol, June 1, 2009; 296(6): F1279 - F1290. [Abstract] [Full Text] [PDF]

				R. Musa-Aziz, L.-M. Chen, M. F. Pelletier, and W. F. Boron Relative CO2/NH3 selectivities of AQP1, AQP4, AQP5, AmtB, and RhAG PNAS, March 31, 2009; 106(13): 5406 - 5411. [Abstract] [Full Text] [PDF]