title: Highly efficient homologous integration via tandem exo-beta-1, 3-glucanase genes in the common mushroom, Agaricus bisporus.
abstract: Homologous integration was studied in the common mushroom, Agaricus bisporus, using a plasmid (pHAG3-1) carrying the hygromycin-resistance gene and a 3.2-kb genomic fragment from A. bisporus. Homologous integration was found in 30-60% of the transformants obtained with pHAG3-1 linearized at three different positions within the homologous sequence, generating either blunt, 5'- or 3'-protruding ends. The genomic fragment was found to contain two homologous open reading frames in tandem, which showed 60% similarity to exo-beta-1,3-glucanases from Saccharomyces cerevisiae and Candida albicans. The level of the corresponding mRNA is low in the vegetative mycelium and relatively high in fruiting bodies. In the vegetative mycelium of a transformant with tandemly integrated pHAG3-1 plasmids at the homologous position, exoglucanase mRNA was strongly increased without any apparent effect on growth rate or morphology.
authors.affiliation: DLO-Institute for Agrotechnological Research (ATO-DLO), Wageningen, The Netherlands.
authors.forename: M D
authors.initials: MD
authors.lastname: van de Rhee
authors.forename: O
authors.initials: O
authors.lastname: Mendes
authors.forename: M W
authors.initials: MW
authors.lastname: Werten
authors.forename: H J
authors.initials: HJ
authors.lastname: Huizing
authors.forename: H
authors.initials: H
authors.lastname: Mooibroek
mesh_terms: D000364:Agaricus / Q000201:enzymology / Q000235:genetics*; D000595:Amino Acid Sequence; D001483:Base Sequence; D015152:Blotting, Northern; D004274:DNA, Recombinant; D005822:Genetic Vectors; D043326:Glucan 1,3-beta-Glucosidase; D008969:Molecular Sequence Data; D014170:Transformation, Genetic; D001617:beta-Glucosidase / Q000235:genetics*
chemical_list: D004274:DNA, Recombinant; D001617:beta-Glucosidase; D043326:Glucan 1,3-beta-Glucosidase