| Popis: |
Cell polarity plays a key role in the development multicellular organisms. Several mechanisms exist to ensure that cytoplasmic determinants are distributed heterogeneously within cells. mRNA localisation, is one such process that targets proteins to their site of function. Although the function of mRNA localisation has been widely studied in various organisms ranging from yeast to mammals, since its discovery 20 years ago the mechanism by which mRNAs are transported to their destination is poorly understood. This thesis studies the mechanism by which grk mRNA localisation, crucial for axis of specification of Drosophila embryos, is transported in oogenesis from the cell where it is transcribed to its final destination in the oocyte. Two in vivo approaches were utilised, to study grk RNA movement in Drosophila oogenesis. Molecular beacons, probes that fluoresce upon hybridisation, were not successful in faithfully detecting endogenous grk mRNA. On the other hand, an injection assay of in vitro transcribed and fluorescently labelled grk RNA in living egg chambers, revealed a microtubule and dynein dependence throughout the entire movement of grk RNA transport from the nurse cells to its final destination in the ooycte. We propose, that other key maternal transcripts are transported and localised in Drosophila oogeoeuia via a similar motor driven mechanism. |
