Blocked endocytotic uptake by the oocyte causes accumulation of vitellogenins in the haemolymph of the female-sterile mutants quitPX61 and stand stillPS34 of Drosophila

Institut für Biologie I, Albert-Ludwigs-Universität, Freiburg, Germany.
Cell and Tissue Research (Impact Factor: 3.57). 03/1994; 275(2):291-8. DOI: 10.1007/BF00319427
Source: PubMed

ABSTRACT The developmental lesions in two female-sterile mutants, quitPX61 (qui) and stand stillPS34 (stil), of Drosophila have been analysed. Previtellogenic development is normal in mutant qui ovarioles but, during vitellogenic stages, only small quantities of yolk accumulate in the oocyte. The nurse-cell cytoplasm does not stream into the oocyte. However, the follicle cells continue their developmental program and synthesize an excessive quantity of eggshell material. In the mutant stil, the oocyte remains small and contains only a fraction of the yolk proteins present in wild-type follicles. Histological and ultrastructural observations and the failure to incorporate trypan blue indicate that the yolk proteins present in the mutant follicles are neither derived from the fat body nor from the follicle cells. Since, in both mutants, the uptake mechanism of vitellogenin is affected, the 3 polypeptides accumulate in the haemolymph (in stil, the protein concentration is up to 4 times higher than in wild-type females) and the haemolymph volume increases. Reciprocal transplantations of ovarioles show that the developmental lesions in both mutants are ovary-autonomous. Furthermore, genetic chimeras of stil show that the activity of the stil gene is required in the germline cells and not in the somatic tissues.

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    • "Interestingly, other fly mutants defective in endocytosis also display male or female sterility, and the latter is associated with abnormal oogenesis, e.g. yolkless, quitPK61, stillPS34, Merlin and clathrinheavy-chain 4 (Bazinet et al., 1993; DiMario and Mahowald, 1987; Dorogova et al., 2008; Gutzeit and Arendt, 1994), and mutants in the C. elegans EHD ortholog rme-1 failed to recycle yolk receptors (Grant et al., 2001). These results highlight the importance of Past1, and endocytosis, in development and maturation of the germlines. "
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    Journal of Cell Science 02/2009; 122(Pt 4):471-80. DOI:10.1242/jcs.038521 · 5.43 Impact Factor
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    • "For live imaging, 0.4% Trypan Blue dye in Graces insect medium was injected into the females abdomen. The dye was endocytosed with the yolk by the oocytes and labels late endosomes containing yolk granules (Danilchik and Denegre, 1991; Gutzeit and Arndt, 1994). After 2 h incubation, the ovaries were dissected under halocarbon oil and covered with a YSI Do membrane (Yellow Springs Instrument, Ohio) for live imaging. "
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    • "For most endosome movies, 1 mg/ml Trypan Blue dye was injected into female fly abdomens and allowed to incubate for 2-7 hours. The dye, endocytosed with yolk by the oocyte, served as a bright fluorescence marker to make yolk granules more visible (B.-J.C., unpublished) (Danilchik and Denegre, 1991; Gutzeit and Arendt, 1994). Ovaries were dissected under halocarbon oil as described (Theurkauf, 1994b; Theurkauf and Hazelrigg, 1998). "
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