Fig. 4: NtDD dimerization is critical for fertility and P granule formation in nematodes.
From: C. elegans germ granules require both assembly and localized regulators for mRNA repression
a Sites of SNAP tag insertion and missense mutations in C. elegans PGL-1. N-terminal dimerization domain (NtDD, yellow), central dimerization domain (CDD, orange), C-terminal region (C-region), SNAP (magenta), and RGG repeats (blue). b Fertility of SNAP-tagged PGL-1 animals. Percentages were obtained after scoring individuals for production of larval progeny after 5 days at either 20 or 25 °C. Statistics reported in Supplementary Fig. 6a. c–p Extruded adult germlines, fixed, stained, and imaged in same region of meiotic pachytene (see Supplementary Fig. 6b). (c–f) Representative images of SNAP staining to visualize PGL-1 expression and granule formation. SNAP in magenta, DNA (DAPI) in cyan. All images are partial Z-stacks to maximize visualization of P granules. Images were taken from germlines containing embryos; similar images were obtained from germlines lacking embryos (Supplementary Fig. 6f, g). (c) PGL-1::SNAP localizes to granules around nuclei (n = 49). (d) Control, wild-type animal lacking SNAP tag shows virtually no background staining (n = 20). (e) PGL-1(K126E K129E)::SNAP is diffuse (n = 38). (f) PGL-1(R123E)::SNAP is diffuse (n = 24). (g–p) Representative images showing localization of three P granule components in germ cells expressing either (g–k) PGL-1::SNAP (n = 20) or (l–p) PGL-1(K126E K129E)::SNAP (n = 14). (g, l) DNA (DAPI, cyan); (h, m) SNAP (PGL-1::SNAP or mutant, magenta); (i, n) V5 (PGL-3, green); (j, o) MYC (GLH-1, red); (k, p) Merge. Scale bar, 10 µm for all images, except 2.5-fold enlargements of nuclei in boxes placed outside main images. n = biologically independent animals examined over 2 independent experiments.
