. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. MOVEMENT IN DROSOPHILA BRIDGES 75. Figure 3. Photographs from the video screen of trans-oblique illu- mination and Fluorescence images recorded with a newvicon camera showing Lucifer yellow injected Dmsophila follicles. The injection nee- dle can be seen impaling a nurse cell in A. B is the fluorescence image taken 15 min after the injection. Note the lack of detectable dye-cou- pling. In C the injection was into an oocyte. D is the fluorescence image recorded 20 mm later. This experiment was repeated 10 times with the same
. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. MOVEMENT IN DROSOPHILA BRIDGES 75. Figure 3. Photographs from the video screen of trans-oblique illu- mination and Fluorescence images recorded with a newvicon camera showing Lucifer yellow injected Dmsophila follicles. The injection nee- dle can be seen impaling a nurse cell in A. B is the fluorescence image taken 15 min after the injection. Note the lack of detectable dye-cou- pling. In C the injection was into an oocyte. D is the fluorescence image recorded 20 mm later. This experiment was repeated 10 times with the same results in each case. An additional observation emerging from these exper- iments was the undetectability of dye-coupling between the oocyte and the follicle epithelial cells (Figs. 2-6). This facilitated the interpretation of dye movement through the intercellular bridges because it ruled out the possibil- ity of an indirect route of migration between oocyte and nurse cells via the epithelium. Discussion The results confirm a charge-dependent polarizing effect operating within the nurse cell-oocyte intercellular bridges. This effect, previously shown to modulate the movement of positive or negative microinjected proteins (Woodruff"el 1988). also influences the distribution of Lucifer yellow CH, a small, highly mobile, negatively charged molecule soluble in the aqueous phase of the cy- tosol (Stewart, 1978). Dye injected into the oocyte does not cross the intercellular bridges into nurse cells in de- tectable amounts, but when injected into nurse cells it not only detectably crosses into the oocyte, but actually becomes more concentrated there. Furthermore, the re- sults confirm, in a very different incubation medium, the electrical gradient described for Drosophila by Woodruff el al. (1988) and suggested to be responsible for enforcing this polarity. An important observation made during this study concerned the level of dye detection. When dye injection into an oocy
Size: 1326px × 1883px
Photo credit: © Library Book Collection / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookauthorlilliefrankrat, booksubjectbiology, booksubjectzoology
