A short regulatory domain restricts glycerol transport through yeast Fps1p


The controlled export of solutes is crucial for cellular adaptation to hypotonic conditions. In the yeast Saccharomyces cerevisiae glycerol export is mediated by Fpslp, a member of the major intrinsic protein (MIP) family ]of channel proteins. Here we describe a short regulatory domain that restricts glycerol transport through Fpslp. This domain is required for retention of cellular glycerol under hypertonic stress and hence acquisition of osmotolerance. It is located in the N-terminal cytoplasmic extension close to the first transmembrane domain. Several residues within that domain and its precise position are critical for channel control while the proximal residues 13-215 of the N-terminal extension are not required. The sequence of the regulatory domain and its position are perfectly conserved in orthologs from other yeast species. The regulatory domain has an amphiphilic character, and structural predictions indicate that it could fold back into the membrane bilayer. Remarkably, this domain has structural similarity to the channel forming loops B and E of Fpslp and other glycerol facilitators. Intragenic second-site suppressor mutations of the sensitivity to high osmolarity conferred by truncation of the regulatory domain caused diminished glycerol transport, confirming that elevated channel activity is the cause of the osmosensitive phenotype.

Publication DOI: https://doi.org/10.1074/jbc.M209792200
Divisions: College of Health & Life Sciences > School of Biosciences
College of Health & Life Sciences
College of Health & Life Sciences > School of Biosciences > Cellular and Molecular Biomedicine
Additional Information: © 2003 by The American Society for Biochemistry and Molecular Biology, Inc.
Uncontrolled Keywords: amino acid sequence,base sequence,biological transport,DNA Primers,glycerol,kinetics,kluyveromyces,membrane proteins,models, molecular,mutagenesis,Mutagenesis, Site-Directed,protein structure, secondary,recombinant proteins,saccharomyces cerevisiae,saccharomyces cerevisiae Proteins,sequence alignment,sequence deletion,sequence homology, amino acid,Biochemistry
Publication ISSN: 1083-351X
Last Modified: 27 Jun 2024 08:00
Date Deposited: 20 Nov 2014 14:35
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Related URLs: http://www.scop ... tnerID=8YFLogxK (Scopus URL)
http://www.jbc. ... 278/8/6337#fn-3 (Publisher URL)
PURE Output Type: Article
Published Date: 2003-02-21
Published Online Date: 2002-12-16
Authors: Tamás, Markus J.
Karlgren, Sara
Bill, Roslyn M. (ORCID Profile 0000-0003-1331-0852)
Hedfalk, Kristina
Allegri, Laura
Ferreira, Marie
Thevelein, Johan M.
Rydström, Jan
Mullins, Jonathan G.L.
Hohmann, Stefan



Version: Published Version

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