Figure 2.

grk mRNA Is Not Associated with P Bodies in Nurse Cells

(A–A′′) In egg chambers expressing Me31B::GFP, P bodies rarely associate (16% of particles, n = 297) with grk mRNA particles labeled with single-molecule FISH in the nurse cell cytoplasm. (A) Me31B::GFP labeling P bodies, (A′) grk mRNA particles labeled with single-molecule FISH, and (A′′′) overlay of Me31B::GFP labeling P bodies in green and single-molecule FISH labeling grk mRNA in red.

(B–B′′′) Consecutive time points in a time-lapse series of a live egg chamber expressing grk^∗mCherry and Me31B::GFP. grk particles (arrowheads) move independently of Me31B assemblies in the nurse cell cytoplasm (n = 89). Dashed red circles indicate the positions of grk particles at t = 0 s.

(C–E) In early oogenesis, grk localized to the oocyte posterior where it is locally translated.

(C) grk smFISH on an early-stage egg chamber showing the localization of grk at the posterior (arrowheads) (n = 5). Inset: schematic illustrating the relative position of the oocyte and nurse cells for a stage 5/6 egg chamber.

(D) Anti-Grk antibody labeling showing the gradient in Grk protein from a local enrichment at the posterior (arrowheads) (n = 5).

(E) Anti-Orb antibody labeling showing increased Orb in the oocyte (arrowheads) (n = 5).

(F–F′′′) Early-stage living egg chamber expressing grk^∗mCherry and Me31B::GFP showing local docking of grk on Me31B-labeled P bodies at the posterior, taken from a time-lapse series (n = 4). (F) Composite image showing the interdigitation of grk with Me31B at the posterior. (F′) Enlargement of the region identified by the dashed box in (F). (F′′) Me31B::GFP showing the decreasing gradient in P body density from posterior to anterior. (F′′′) grk^∗mCherry showing the locally docked grk mRNA at the posterior.

Scale bars, 2 μm (A and B) and 10 μm (C and F).