File:Ovocito Drosophila The transport of oskar mRNA from the nurse cell nucleus. panel I.png

English: Fig.1B_Oskar mRNP dynamics during stage7-10 oocytes.

(B) A cocktail of molecular beacons labeled with Cy5 fluorophore and complementary to several regions of native oskar mRNA was injected into the nurse cell nuclei of a stage 9 egg chamber. The transport of oskar mRNA from the nurse cell nucleus to the posterior cortex of the oocyte is directly visualized in vivo. We acquired images continuously taking 18 optical slices of 1.2 µm in size over a period of 20 min. A central optical slice projected over 200 time points is represented in red. The tracks of several particles are traced in the oocyte in white dash lines.

The first and last time point frames (green&yellow) (panel I and II, respectively) are merged with the time projection image to indicate the position of the particles at the beginning and the end of the tracked paths inside the oocyte. These tracks reflect directional movement towards the posterior pole. Individual particles are observed transiting through the ring canal, accumulating over time in the oocyte, and forming a crescent of oskar mRNA associated with the posterior (arrows). Scale bar = 25 µm. See Movies S2 & S4.