Figure 3.
Figure 3. Germ cell rachis bridge formation arises progressively during larval development. (A) Schematic representation of the adult hermaphrodite germline. ANI-2 (green) lines up at the periphery of the central rachis and is enriched at rachis bridges, and it is delocalized upon oocyte cellularization. (B and E) Mid-section confocal images of the germline of a wild-type adult (B) and L3 (E) hermaphrodites expressing GFP::ANI-2 (green) and a membrane marker (red). Bar, 10 µm. The regions delineated by the white dashed square are magnified in the inset (bar for insets, 5 µm). In B, the white arrowhead points to the germ cell opening to the rachis. (C) Schematic representation of germ cells as in A depicting the method for measuring rachis bridge organization. Fluorescence intensity is measured along the lateral and apical cortices (line shown in black). Arrows point to the position of the rachis bridge as seen in mid-section images, and the arrowhead points to the germ cell opening to the rachis. (D and F) Measured fluorescence intensities (in arbitrary units) for each fluorescent marker along the lateral and apical cortices (white dotted line, as shown in insets; bar for insets, 5 µm) of the germ cell magnified in B and E, respectively. Red and green arrows point to peaks of membrane marker and GFP::ANI-2 fluorescence intensities, respectively. Both peaks border a minimum in fluorescence intensity (black arrowhead) that corresponds to the germ cell opening to the rachis. (G) Proportion of germ cells showing rachis bridges with a diameter >0.8 µm (turquoise) or <0.8 µm (red) throughout larval development, as measured by fluorescent marker distribution. (H) Maximal rachis bridge diameter in germ cells throughout larval development, as measured with GFP::ANI-2 (green) or membrane (red) fluorescence distribution. Error bars represent SD. In G and H the numbers in brackets represent the total number of germ cells analyzed. (I) Mid-section confocal images of an embryo expressing GFP::PGL-1 (green) exogenously supplied with photo-convertible rhodamine-dextran (gray). Time is relative to fluorescence photoactivation (at time 0) in one of the two primordial germ cells (blue dashed circle). The sister cell is delineated by a red dashed circle and the green dashed circle delineates a nearby somatic cell. Bar, 10 µm. (J) Fold-increase (from time 0) in fluorescence intensity over time measured in each cell shown in I. Error bars represent SD over 13 embryos.

Germ cell rachis bridge formation arises progressively during larval development. (A) Schematic representation of the adult hermaphrodite germline. ANI-2 (green) lines up at the periphery of the central rachis and is enriched at rachis bridges, and it is delocalized upon oocyte cellularization. (B and E) Mid-section confocal images of the germline of a wild-type adult (B) and L3 (E) hermaphrodites expressing GFP::ANI-2 (green) and a membrane marker (red). Bar, 10 µm. The regions delineated by the white dashed square are magnified in the inset (bar for insets, 5 µm). In B, the white arrowhead points to the germ cell opening to the rachis. (C) Schematic representation of germ cells as in A depicting the method for measuring rachis bridge organization. Fluorescence intensity is measured along the lateral and apical cortices (line shown in black). Arrows point to the position of the rachis bridge as seen in mid-section images, and the arrowhead points to the germ cell opening to the rachis. (D and F) Measured fluorescence intensities (in arbitrary units) for each fluorescent marker along the lateral and apical cortices (white dotted line, as shown in insets; bar for insets, 5 µm) of the germ cell magnified in B and E, respectively. Red and green arrows point to peaks of membrane marker and GFP::ANI-2 fluorescence intensities, respectively. Both peaks border a minimum in fluorescence intensity (black arrowhead) that corresponds to the germ cell opening to the rachis. (G) Proportion of germ cells showing rachis bridges with a diameter >0.8 µm (turquoise) or <0.8 µm (red) throughout larval development, as measured by fluorescent marker distribution. (H) Maximal rachis bridge diameter in germ cells throughout larval development, as measured with GFP::ANI-2 (green) or membrane (red) fluorescence distribution. Error bars represent SD. In G and H the numbers in brackets represent the total number of germ cells analyzed. (I) Mid-section confocal images of an embryo expressing GFP::PGL-1 (green) exogenously supplied with photo-convertible rhodamine-dextran (gray). Time is relative to fluorescence photoactivation (at time 0) in one of the two primordial germ cells (blue dashed circle). The sister cell is delineated by a red dashed circle and the green dashed circle delineates a nearby somatic cell. Bar, 10 µm. (J) Fold-increase (from time 0) in fluorescence intensity over time measured in each cell shown in I. Error bars represent SD over 13 embryos.

This Feature Is Available To Subscribers Only

or Create an Account

Close Modal
Close Modal