title: A hyperactive transposase of the maize transposable element activator (Ac).
abstract: Activator/Dissociation (Ac/Ds) transposable elements from maize are widely used as insertional mutagenesis and gene isolation tools in plants and more recently also in medaka and zebrafish. They are particularly valuable for plant species that are transformation-recalcitrant and have long generation cycles or large genomes with low gene densities. Ac/Ds transposition frequencies vary widely, however, and in some species they are too low for large-scale mutagenesis. We discovered a hyperactive Ac transposase derivative, AcTPase(4x), that catalyzes in the yeast Saccharomyces cerevisiae 100-fold more frequent Ds excisions than the wild-type transposase, whereas the reintegration frequency of excised Ds elements is unchanged (57%). Comparable to the wild-type transposase in plants, AcTPase(4x) catalyzes Ds insertion preferentially into coding regions and to genetically linked sites, but the mutant protein apparently has lost the weak bias of the wild-type protein for insertion sites with elevated guanine-cytosine content and nonrandom protein-DNA twist. AcTPase(4x) exhibits hyperactivity also in Arabidopsis thaliana where it effects a more than sixfold increase in Ds excision relative to wild-type AcTPase and thus may be useful to facilitate Ac/Ds-based insertion mutagenesis approaches.
authors.affiliation: Dahlem Centre of Plant Sciences, Freie Universität Berlin, 14195 Berlin, Germany.
authors.forename: Katina
authors.initials: K
authors.lastname: Lazarow
authors.forename: My-Linh
authors.initials: ML
authors.lastname: Du
authors.forename: Ruth
authors.initials: R
authors.lastname: Weimer
authors.forename: Reinhard
authors.initials: R
authors.lastname: Kunze
mesh_terms: D020816:Amino Acid Motifs; D000595:Amino Acid Sequence; D019943:Amino Acid Substitution; D017360:Arabidopsis / Q000201:enzymology; D001483:Base Sequence; D017124:Conserved Sequence; D004251:DNA Transposable Elements / Q000235:genetics*; D008969:Molecular Sequence Data; D012441:Saccharomyces cerevisiae / Q000201:enzymology; D019895:Transposases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D003313:Zea mays / Q000201:enzymology* / Q000235:genetics*
chemical_list: D004251:DNA Transposable Elements; D019895:Transposases