gurken and the I factor retrotransposon RNAs share common localization signals and machinery.
Drosophila gurken mRNA is localized by dynein-mediated transport to a crescent near the oocyte nucleus, thus targeting the TGFalpha signal and forming the primary embryonic axes. Here, we show that gurken and the I factor, a non-LTR retrotransposon, share a small consensus RNA stem loop of defined secondary structure, which forms a conserved signal for dynein-mediated RNA transport to the oocyte nucleus. Furthermore, gurken and the I factor compete in vivo for the same localization machinery. I factor transposition leads to its mRNA accumulating near and within the oocyte nucleus, thus causing perturbations in gurken and bicoid mRNA localization and axis specification. These observations further our understanding of the close association of transposable elements with their host and provide an explanation for how I factor transposition causes female sterility. We propose that the transposition of other elements may exploit the host's RNA transport signals and machinery.
Wellcome Trust Centre for Cell Biology, School of Biological Sciences, Kings Buildings, The University of Edinburgh, Edinburgh EH9 3JR, United Kingdom.
Véronique
V
Van De Bor
Eve
E
Hartswood
Cheryl
C
Jones
David
D
Finnegan
Ilan
I
Davis
D000818:Animals; D001483:Base Sequence; D002467:Cell Nucleus / Q000235:genetics / Q000378:metabolism; D004330:Drosophila / Q000235:genetics / Q000378:metabolism*; D029721:Drosophila Proteins / Q000235:genetics / Q000378:metabolism*; D004398:Dyneins / Q000378:metabolism; D005260:Female; D018398:Homeodomain Proteins / Q000235:genetics / Q000378:metabolism; D008969:Molecular Sequence Data; D009690:Nucleic Acid Conformation; D009865:Oocytes / Q000502:physiology; D009866:Oogenesis / Q000235:genetics / Q000502:physiology; D012313:RNA / Q000235:genetics / Q000378:metabolism*; D034443:RNA Transport; D012333:RNA, Messenger / Q000378:metabolism; D018626:Retroelements / Q000235:genetics / Q000502:physiology*; D012689:Sequence Homology, Nucleic Acid; D015534:Trans-Activators / Q000235:genetics / Q000378:metabolism; D016211:Transforming Growth Factor alpha / Q000235:genetics / Q000378:metabolism*
D029721:Drosophila Proteins; D018398:Homeodomain Proteins; D012333:RNA, Messenger; D018626:Retroelements; D015534:Trans-Activators; D016211:Transforming Growth Factor alpha; C056478:bcd protein, Drosophila; C083730:grk protein, Drosophila; D012313:RNA; D004398:Dyneins