title: A rapid and efficient method to generate multiple gene disruptions in Dictyostelium discoideum using a single selectable marker and the Cre-loxP system.
abstract: Dictyostelium discoideum has proven an exceptionally powerful system for studying numerous aspects of cellular and developmental functions. The relatively small ( approximately 34 Mb) chromosomal genome of Dictyostelium and high efficiency of targeted gene disruption have enabled researchers to characterize many specific gene functions. However, the number of selectable markers in Dictyostelium is restricted, as is the ability to perform effective genetic crosses between strains. Thus, it has been difficult to create multiple mutations within an individual cell to study epistatic relationships among genes or potential redundancies between various pathways. We now describe a robust system for the production of multiple gene mutations in Dictyostelium by recycling a single selectable marker, Blasticidin S resistance, using the Cre-loxP system. We confirm the effectiveness of the system by generating a single cell carrying four separate gene disruptions. Furthermore, the cells remain sensitive to transformation for additional targeted or random mutagenesis requiring Blasticidin selection and for functional expression studies of mutated or tagged proteins using other selectable markers.
authors.affiliation: A. Butenandt-Institut/Zellbiologie, Ludwig-Maximilians-Universität München, D-80336 München, Germany.
authors.forename: Jan
authors.initials: J
authors.lastname: Faix
authors.forename: Lisa
authors.initials: L
authors.lastname: Kreppel
authors.forename: Gad
authors.initials: G
authors.lastname: Shaulsky
authors.forename: Michael
authors.initials: M
authors.lastname: Schleicher
authors.forename: Alan R
authors.initials: AR
authors.lastname: Kimmel
mesh_terms: D000818:Animals; D004023:Dictyostelium / Q000187:drug effects / Q000235:genetics*; D004351:Drug Resistance; D018390:Gene Targeting / Q000379:methods*; D005819:Genetic Markers; D019426:Integrases / Q000378:metabolism*; D009154:Mutation; D009705:Nucleosides / Q000494:pharmacology; D011995:Recombination, Genetic; D014764:Viral Proteins / Q000378:metabolism*
chemical_list: D005819:Genetic Markers; D009705:Nucleosides; D014764:Viral Proteins; C004500:blasticidin S; C045073:Cre recombinase; D019426:Integrases