title: Controlled expression of recombinant proteins in Physcomitrella patens by a conditional heat-shock promoter: a tool for plant research and biotechnology.
abstract: The ability to express tightly controlled amounts of endogenous and recombinant proteins in plant cells is an essential tool for research and biotechnology. Here, the inducibility of the soybean heat-shock Gmhsp17.3B promoter was addressed in the moss Physcomitrella patens, using beta-glucuronidase (GUS) and an F-actin marker (GFP-talin) as reporter proteins. In stably transformed moss lines, Gmhsp17.3B-driven GUS expression was extremely low at 25 degrees C. In contrast, a short non-damaging heat-treatment at 38 degrees C rapidly induced reporter expression over three orders of magnitude, enabling GUS accumulation and the labelling of F-actin cytoskeleton in all cell types and tissues. Induction levels were tightly proportional to the temperature and duration of the heat treatment, allowing fine-tuning of protein expression. Repeated heating/cooling cycles led to the massive GUS accumulation, up to 2.3% of the total soluble proteins. The anti-inflammatory drug acetyl salicylic acid (ASA) and the membrane-fluidiser benzyl alcohol (BA) also induced GUS expression at 25 degrees C, allowing the production of recombinant proteins without heat-treatment. The Gmhsp17.3B promoter thus provides a reliable versatile conditional promoter for the controlled expression of recombinant proteins in the moss P. patens.
authors.affiliation: Department of Plant Molecular Biology, Lausanne University, Lausanne CH-1015, Switzerland.
authors.forename: Younousse
authors.initials: Y
authors.lastname: Saidi
authors.forename: Andrija
authors.initials: A
authors.lastname: Finka
authors.forename: Mickhail
authors.initials: M
authors.lastname: Chakhporanian
authors.forename: Jean-Pierre
authors.initials: JP
authors.lastname: Zrÿd
authors.forename: Didier G
authors.initials: DG
authors.lastname: Schaefer
authors.forename: Pierre
authors.initials: P
authors.lastname: Goloubinoff
mesh_terms: D001241:Aspirin / Q000494:pharmacology; D019905:Benzyl Alcohol / Q000494:pharmacology; D001709:Biotechnology / Q000379:methods*; D019068:Bryopsida / Q000187:drug effects / Q000235:genetics* / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D004790:Enzyme Induction; D015971:Gene Expression Regulation, Enzymologic / Q000235:genetics; D018506:Gene Expression Regulation, Plant / Q000187:drug effects / Q000235:genetics*; D006360:Heat-Shock Proteins / Q000235:genetics*; D010940:Plant Proteins / Q000235:genetics* / Q000378:metabolism; D011401:Promoter Regions, Genetic / Q000235:genetics*; D011994:Recombinant Proteins / Q000235:genetics* / Q000378:metabolism; D013696:Temperature; D013995:Time
chemical_list: D006360:Heat-Shock Proteins; D010940:Plant Proteins; D011994:Recombinant Proteins; D019905:Benzyl Alcohol; D001241:Aspirin