Crystal structure of a yeast aquaporin at 1.15 Å reveals a novel gating mechanism
(2009) In PLoS Biology 7(6). p.1-13- Abstract
Aquaporins are transmembrane proteins that facilitate the flow of water through cellular membranes. An unusual characteristic of yeast aquaporins is that they frequently contain an extended N terminus of unknown function. Here we present the X-ray structure of the yeast aquaporin Aqy1 from Pichia pastoris at 1.15 Å resolution. Our crystal structure reveals that the water channel is closed by the N terminus, which arranges as a tightly wound helical bundle, with Tyr31 forming H-bond interactions to a water molecule within the pore and thereby occluding the channel entrance. Nevertheless, functional assays show that Aqy1 has appreciable water transport activity that aids survival during rapid freezing of P. pastoris. These findings... (More)
Aquaporins are transmembrane proteins that facilitate the flow of water through cellular membranes. An unusual characteristic of yeast aquaporins is that they frequently contain an extended N terminus of unknown function. Here we present the X-ray structure of the yeast aquaporin Aqy1 from Pichia pastoris at 1.15 Å resolution. Our crystal structure reveals that the water channel is closed by the N terminus, which arranges as a tightly wound helical bundle, with Tyr31 forming H-bond interactions to a water molecule within the pore and thereby occluding the channel entrance. Nevertheless, functional assays show that Aqy1 has appreciable water transport activity that aids survival during rapid freezing of P. pastoris. These findings establish that Aqy1 is a gated water channel. Mutational studies in combination with molecular dynamics simulations imply that gating may be regulated by a combination of phosphorylation and mechanosensitivity.
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- author
- Fischer, Gerhard ; Kosinska-Eriksson, Urszula ; Aponte-Santamaría, Camilo ; Palmgren, Madelene ; Geijer, Cecilia ; Hedfalk, Kristina ; Hohmann, Stefan ; de Groot, Bert L. ; Neutze, Richard and Lindkvist-Petersson, Karin LU
- publishing date
- 2009-06
- type
- Contribution to journal
- publication status
- published
- in
- PLoS Biology
- volume
- 7
- issue
- 6
- article number
- e1000130
- pages
- 1 - 13
- publisher
- Public Library of Science (PLoS)
- external identifiers
-
- scopus:67649963000
- ISSN
- 1545-7885
- DOI
- 10.1371/journal.pbio.1000130
- language
- English
- LU publication?
- no
- id
- ff217e41-68d3-40db-859d-a0125cfa98be
- date added to LUP
- 2017-02-14 16:38:12
- date last changed
- 2022-03-24 08:12:00
@article{ff217e41-68d3-40db-859d-a0125cfa98be, abstract = {{<p>Aquaporins are transmembrane proteins that facilitate the flow of water through cellular membranes. An unusual characteristic of yeast aquaporins is that they frequently contain an extended N terminus of unknown function. Here we present the X-ray structure of the yeast aquaporin Aqy1 from Pichia pastoris at 1.15 Å resolution. Our crystal structure reveals that the water channel is closed by the N terminus, which arranges as a tightly wound helical bundle, with Tyr31 forming H-bond interactions to a water molecule within the pore and thereby occluding the channel entrance. Nevertheless, functional assays show that Aqy1 has appreciable water transport activity that aids survival during rapid freezing of P. pastoris. These findings establish that Aqy1 is a gated water channel. Mutational studies in combination with molecular dynamics simulations imply that gating may be regulated by a combination of phosphorylation and mechanosensitivity.</p>}}, author = {{Fischer, Gerhard and Kosinska-Eriksson, Urszula and Aponte-Santamaría, Camilo and Palmgren, Madelene and Geijer, Cecilia and Hedfalk, Kristina and Hohmann, Stefan and de Groot, Bert L. and Neutze, Richard and Lindkvist-Petersson, Karin}}, issn = {{1545-7885}}, language = {{eng}}, number = {{6}}, pages = {{1--13}}, publisher = {{Public Library of Science (PLoS)}}, series = {{PLoS Biology}}, title = {{Crystal structure of a yeast aquaporin at 1.15 Å reveals a novel gating mechanism}}, url = {{http://dx.doi.org/10.1371/journal.pbio.1000130}}, doi = {{10.1371/journal.pbio.1000130}}, volume = {{7}}, year = {{2009}}, }