title: Boosting heterologous protein production in transgenic dicotyledonous seeds using Phaseolus vulgaris regulatory sequences.
abstract: Over the past decade, several high value proteins have been produced in different transgenic plant tissues such as leaves, tubers, and seeds. Despite recent advances, many heterologous proteins accumulate to low concentrations, and the optimization of expression cassettes to make in planta production and purification economically feasible remains critical. Here, the regulatory sequences of the seed storage protein gene arcelin 5-I (arc5-I) of common bean (Phaseolus vulgaris) were evaluated for producing heterologous proteins in dicotyledonous seeds. The murine single chain variable fragment (scFv) G4 (ref. 4) was chosen as model protein because of the current industrial interest in producing antibodies and derived fragments in crops. In transgenic Arabidopsis thaliana seed stocks, the scFv under control of the 35S promoter of the cauliflower mosaic virus (CaMV) accumulated to approximately 1% of total soluble protein (TSP). However, a set of seed storage promoter constructs boosted the scFv accumulation to exceptionally high concentrations, reaching no less than 36.5% of TSP in homozygous seeds. Even at these high concentrations, the scFv proteins had antigen-binding activity and affinity similar to those produced in Escherichia coli. The feasibility of heterologous protein production under control of arc5-I regulatory sequences was also demonstrated in Phaseolus acutifolius, a promising crop for large scale production.
authors.affiliation: Department of Plant Systems Biology, Flanders Interuniversity Institute for Biotechnology, Ghent University, K.L. Ledeganckstraat 35, B 9000 Gent, Belgium. anna.depicker@rug.ac.be
authors.forename: Geert
authors.initials: G
authors.lastname: De Jaeger
authors.forename: Stanley
authors.initials: S
authors.lastname: Scheffer
authors.forename: Anni
authors.initials: A
authors.lastname: Jacobs
authors.forename: Mukund
authors.initials: M
authors.lastname: Zambre
authors.forename: Oliver
authors.initials: O
authors.lastname: Zobell
authors.forename: Alain
authors.initials: A
authors.lastname: Goossens
authors.forename: Ann
authors.initials: A
authors.lastname: Depicker
authors.forename: Geert
authors.initials: G
authors.lastname: Angenon
mesh_terms: D017360:Arabidopsis / Q000235:genetics / Q000378:metabolism*; D018548:Cotyledon / Q000235:genetics / Q000378:metabolism; D005240:Feasibility Studies; D018506:Gene Expression Regulation, Plant; D006023:Glycoproteins / Q000235:genetics* / Q000378:metabolism; D036341:Intercellular Signaling Peptides and Proteins; D027805:Phaseolus / Q000235:genetics* / Q000378:metabolism; D010940:Plant Proteins / Q000096:biosynthesis / Q000235:genetics* / Q000378:metabolism; D030821:Plants, Genetically Modified; D011506:Proteins; D011994:Recombinant Proteins / Q000096:biosynthesis*; D012639:Seeds / Q000235:genetics / Q000378:metabolism*; D014170:Transformation, Genetic
chemical_list: D006023:Glycoproteins; D036341:Intercellular Signaling Peptides and Proteins; D010940:Plant Proteins; D011506:Proteins; D011994:Recombinant Proteins; C090486:arcelin 5 protein, Phaesolus vulgaris