Genetic instability in Drosophila melanogaster: P-element mutagenesis by gene conversion

• Published in: Proceedings of the National Academy of Sciences - PNAS Vol. 85; no. 17; pp. 6455 - 6459
• Main Authors: Geyer, P.K, Richardson, K.L, Corces, V.G, Green, M.M
• Format: Journal Article
• Language: English
• Published: Washington, DC National Academy of Sciences of the United States of America 01.09.1988; National Acad Sciences
• Subjects: Alleles; Animals; Base Sequence; Biological and medical sciences; DNA; DNA Restriction Enzymes; DNA Transposable Elements; DROSOPHILA; Drosophila melanogaster; Drosophila melanogaster - genetics; Drosophilidae; Fundamental and applied biological sciences. Psychology; GENE; Gene Conversion; GENES; Genetic loci; Genetic mutation; GENETICA; GENETICS; GENETIQUE; Genic rearrangement. Recombination. Transposable element; Messenger RNA; Molecular and cellular biology; Molecular genetics; Molecular Sequence Data; MUTACION; MUTATION; NUCLEOTIDE; Nucleotide Mapping; NUCLEOTIDES; NUCLEOTIDOS; Phenotypes; RECOMBINACION; RECOMBINAISON; RECOMBINATION; RNA; Sex chromosomes; Transcription, Genetic; Transposons; PM system; Mutagenesis; Arthropoda; Insecta; P element; Transposable element; Invertebrata; Gene conversion; Diptera; Drosophilidae
• ISSN: 0027-8424; 1091-6490
• DOI: 10.1073/pnas.85.17.6455

We report the molecular characterization of several P element-induced mutations and their revertants at the yellow (y) locus of Drosophila melanogaster. One of the mutants analyzed, y76d28, results from the insertion of a P element into the 5′-transcribed, untranslated portion of the y gene. Sequence analysis of several revertants of y76d28 shows that P excision occurs imprecisely. These events result in insertion of additional ATG codons in the y locus mRNA but are without phenotypic effect. In addition, we describe the molecular structure of P-associated mutations induced in a near wild-type revertant of y76d28 that carries an internally deleted 0.4-kilobase P element in the 5′ noncoding region. Sequence analysis of two of these mutants demonstrates that they arose as a result of the integration of a larger P element at the exact location as in the parental stock without the 8-base-pair additional duplication associated with P insertions. The phenotype of these y alleles is dependent on the size and orientation of the integrated P element. We infer that P-element replacement in these mutants has occurred by a recombination/gene conversion mechanism.