Fig. 1: Meiotic stress granule (SG) biogenesis features extreme sensitivity to heat.
From: Rim4-seeded stress granules connect temperature sensing to meiotic regulation
A Top: the schematic depicts the domains of the Rim4 protein. RRM: RNA Recognition Motif. IDR: Intrinsically Disordered Region. Bottom: schematic illustrates the process of meiosis. The period of Rim4 activity is indicated. B 3D structure of Rim4 predicted by AlphaFold2. Yellow/blue: low/high confidence of the prediction. C–E GFP-Rim4 primarily forms reversible foci in prophase-I cells under heat. C Representative confocal fluorescence microscopy (FM) images. Top: GFP-Rim4 foci (white arrows) formation under indicated treatment. Bottom: the disassembly of heat-induced GFP-Rim4 foci (42 °C 10 min) after the relief of heat. D, E Percentages of cells in (C) with 0, 1–5, or more than 5 foci (D) under stress conditions and E during recovery from heat. N (cells) = D 152, 123, 143, 137, 133, 140; E all 126. F, G Thermal GFP-Rim4 foci co-localize with mScarlet-Pab1. F Representative FM images. White arrows: co-localization between Rim4 and Pab1. Yellow box, 3× zoomed in (bottom panel), showing the gray values along the yellow dashed line (distance). r-value: Pearson’s correlation. G the percentage of co-localization among (Pab1/Rim4, beige) GFP-Rim4 foci or (Rim4/Pab1, brown) mScarlet-Pab1 foci per cell. Dots: cells analyzed. Red lines: mean ± standard error (SE) confidence interval (CI). N (cells) = 100. H Representative fluorescent in situ hybridization (FISH) images. The gray values of GFP-Rim4, mScarlet-Pab1, and mRNAs along a yellow dashed line in one cell (zoomed in 3×) were plotted as described in (F). I–K GFP-Rim4 foci formation between 25 °C and 42 °C. I Representative time course FM images. J Standard deviation (SD) of the average GFP-Rim4 signal in. N (cells) = 122, 123, 102, 114, 110, 106. Red lines: median ± 95% CI. Unpaired two-sided Mann–Whitney test. p-values: a: 3.09e-19 (***); b: 3.92e-33 (***); c: 3.66e-39 (***); d: 1.99e-39 (***); f: 1.49e-38 (***). K Average foci number per cell. N (cells) = (42 °C) 123; (40 °C) 120; (37 °C) 148; (33 °C) 157; (30 °C) 161; (25 °C) 142. Data are presented as mean ± SE. Scale bars are 5 µm.
