Identification of a potential RNA intermediate for transposition of the LINE-like element I factor in Drosophila melanogaster.
The I factor, a transposable element related to mammalian LINEs, controls the I-R system of hybrid dysgenesis in Drosophila melanogaster. It transposes at high frequency in the germ-line of the female progeny of crosses between females of the reactive class of strains and males of the inducer class. The structure and DNA sequence of the I factor suggest that it transposes by reverse transcription of an RNA intermediate. Northern blot and S1 mapping experiments show that a full-length RNA of the I factor is synthesized specifically in the conditions of which I factors transpose. This RNA has all characteristics of a transposition intermediate. It is only found in the ovaries of dysgenic females suggesting that I factor activity is restricted to this tissue because of regulation at the level of the initiation of transcription or RNA stability.
Laboratoire de Génétique, Université Blaise Pascal, Aubière, France.
M C
MC
Chaboissier
I
I
Busseau
J
J
Prosser
D J
DJ
Finnegan
A
A
Bucheton
D000818:Animals; D015152:Blotting, Northern; D003001:Cloning, Molecular; D004251:DNA Transposable Elements; D004331:Drosophila melanogaster / Q000235:genetics*; D005260:Female; D005796:Genes; D006570:Heterochromatin; D006824:Hybridization, Genetic; D007247:Infertility, Female / Q000235:genetics / Q000662:veterinary; D010053:Ovary / Q000502:physiology; D011061:Poly A / Q000378:metabolism; D012313:RNA / Q000235:genetics*; D012326:RNA Splicing; D012091:Repetitive Sequences, Nucleic Acid; D015183:Restriction Mapping; D014158:Transcription, Genetic
D004251:DNA Transposable Elements; D006570:Heterochromatin; D011061:Poly A; D012313:RNA