Fig. 3: The retarded pre-ribosome assembly in atprmt3 mutants is rescued by mutation of PDCD2.

a The subcellular distribution of PDCD2/PDCD2^E350K from Col-0, atprmt3-2, and atprmt3pdcd2-d1. Protein lysates were immunoblotted with anti-PDCD2, anti-PEPC, and anti-H3 antibodies after subcellular fractionation. PEPC (phosphoenolpyruvate carboxylase) and histone H3 were used as markers for cytoplasm and nucleus, respectively. Data are presented as mean values ± SD (n = 3). b Gel filtration patterns of PDCD2/PDCD2^E350K in Col-0, atprmt3-2, and atprmt3pdcd2-d1. Protein lysates were fractioned by gel filtration and immunoblotted with anti-PDCD2 antibody. Ponceau S staining was used as a control. Experiments were repeated two times with similar results. c Protoplast expressing PDCD2-GFP treated with or without leptomycin B (LMB) (n = 20). Nucleus are stained by Hochest in blue. Scale bar, 5 μm. Experiments were repeated two times with similar results. d, e Phenotypes of Col-0, atprmt3-2, atprmt3pdcd2-d1, and hos1atprmt3pdcd2-d1. Scale bar, 1 cm. Data are presented as mean values ± SD (n = 25). f Schematic of the DIA-MS analysis. Nuclear protein from Col-0, atprmt3-2, and atprmt3pdcd2-d1 were applied for MS (n = 3). Venn diagram showed the up-regulated proteins in atprmt3-2, and atprmt3pdcd2-d1 compared with Col-0. P < 0.0001 was calculated by two-sided Fisher’s exact test. g Gene Ontology analysis (Biological Process) of the 847 proteins in (f). h The RNA FISH of pre-rRNAs in Col-0, atprmt3-2, and atprmt3pdcd2-d1. Pre-rRNAs are probed by Cy3-S7, DAPI stain is the nucleus, scale bar, 5 μm. Violin plot shows the quantitative measurement of nucleolar area ratio (nucleolus/nucleus) (n = 248, 226, 234). The horizontal solid lines represent the median; the horizontal dashed lines represent the quartile. Experiments were repeated two times with similar results. P value was calculated by One-way ANOVA with Dunnett’s multiple comparisons test. Source data are provided as a Source Data file.