Fig. 1. Proximal streaming in the wild-type C. elegans gonad. (A) Diagram of one arm of an adult hermaphrodite gonad. Plasma membranes, red; nuclei, blue. Somatic sheath cells enclose most of the gonad, but are not shown for simplicity. (B) Single image from time-lapse movie. DIC particles are shown at high magnification in inset. (C) 2-minute particle tracks. Arrows indicate final positions of particles and dots indicate stationary particles. Most particles ceased movement in cellularized oocytes; the small arrows shown result primarily from a shift in oocyte position. (D-G) Movement of PGL-1::GFP particles. (D) Low magnification view of gonad indicating perinuclear P granules (arrow) and detached, cytoplasmic P granules (arrowhead). (E-G) Time-lapse series of boxed region in D. Particles tracked are a perinuclear P granule (orange circle) and cytoplasmic PGL-1::GFP particles (green square and yellow triangle). Movements are summarized in G. (H) Low magnification view of gonad showing PGL-1:: mRFP-1 (red) and mitochondria (green). For movements of mitochondria see Movie 1 in the supplementary material. (I-K) Time-lapse images of a single PGL-1::mRFP-1 particle (arrowhead). Time is shown in minutes. (L) Composite of particle positions at 15 time points in 30-second intervals. (M) Diagram of bulk particle movement (green). Scale bars: 30 µm in B; 3 µm in B inset; 10 µm in E,J.