title: An intact RNA interference pathway is required for expression of the mutant wing phenotype of vg(21-3), a P-element-induced allele of the vestigial gene in Drosophila.
abstract: We have determined that two P elements, P[21-3] and P[21r36], residing in the 5'-UTR of the vestigial wing gene, encode functional repressors in eye tissue. However, neither element fits a previous categorization of repressor-making elements as Type I or II. Both elements encode polypeptides that are shorter than the canonical elements they most closely resemble. DNA sequencing reveals that P[21r36] encodes an intact THAP domain that is missing in the P[21] element, which does not encode a functional repressor. Recovery of P[21-3] at sites other than vestigial (where it causes the wing mutant, vg(21-3)) reveals that the element can make repressor in wing tissue of sufficient activity to repress the mutant phenotype of vg(21-3). Why the P[21-3] element fails to produce repressor when located at vestigial may be explained by our observation that three different mutants in the RNA interference pathway cause a partial reversion of vg(21-3). We speculate that the vg and P-initiated transcripts that arise at the vg locus in the vg(21-3) mutant trigger an RNA interference response that results in the mutual degradation of both transcripts.
authors.affiliation: Department of Biological Sciences, University of Alberta, Edmonton, Canada. ross.hodgetts@ualberta.ca
authors.forename: Ross B
authors.initials: RB
authors.lastname: Hodgetts
authors.forename: Sandra L
authors.initials: SL
authors.lastname: O'Keefe
authors.forename: Kyle J
authors.initials: KJ
authors.lastname: Anderson
mesh_terms: D000483:Alleles; D000818:Animals; D059006:Chromosomes, Insect; D004251:DNA Transposable Elements; D004330:Drosophila / Q000235:genetics*; D029721:Drosophila Proteins / Q000235:genetics*; D005260:Female; D015870:Gene Expression; D005786:Gene Expression Regulation; D023061:Gene Order; D005838:Genotype; D008297:Male; D009154:Mutation; D009687:Nuclear Proteins / Q000235:genetics*; D016366:Open Reading Frames; D010641:Phenotype; D034622:RNA Interference; D011995:Recombination, Genetic; D014921:Wings, Animal / Q000033:anatomy & histology
chemical_list: D004251:DNA Transposable Elements; D029721:Drosophila Proteins; D009687:Nuclear Proteins; C095064:vg protein, Drosophila