title: The molecular basis of P-M hybrid dysgenesis: the role of the P element, a P-strain-specific transposon family.
abstract: We have shown previously that four of five white mutant alleles arising in P-M dysgenic hybrids result from the insertion of strongly homologous DNA sequence elements. We have named these P elements. We report that P elements are present in 30-50 copies per haploid genome in all P strains examined and apparently are missing entirely from all M strains examined, with one exception. Furthermore, members of the P family apparently transpose frequently in P-M dysgenic hybrids; chromosomes descendant from P-M dysgenic hybrids frequently show newly acquired P elements. Finally, the strain-specific breakpoint hotspots for the rearrangement of the pi 2 P X chromosome occurring in P-M dysgenic hybrids are apparently sites of residence of P elements. These observations strongly support the P factor hypothesis for the mechanistic basis of P-M hybrid dysgenesis.
mesh_terms: D001483:Base Sequence; D005075:Biological Evolution; D004251:DNA Transposable Elements; D004330:Drosophila / Q000235:genetics*; D005260:Female; D005786:Gene Expression Regulation; D006824:Hybridization, Genetic; D007246:Infertility / Q000235:genetics; D008297:Male; D011995:Recombination, Genetic; D012091:Repetitive Sequences, Nucleic Acid
chemical_list: D004251:DNA Transposable Elements