Fig. 3: FXR1 assembles various partners to form distinct mRNP condensates.

a Colocalization of FXR1 with target mRNAs in fixed hESCs, and red arrows indicate representative colocalized puncta; Images are representative of cells from three independent experiments. b Distance of mRNP condensates from the nuclear membrane; MDFI n(condensate) = 200; PHF5A n(condensate) = 200; DDIT4 n(condensate) = 200; TRAPPC3 n(condensate) = 200; AHCTF1 n(condensate) = 200; NUP358 n(condensate) = 200; NUP153 n(condensate) = 177; NUP214 n(condensate) = 82. c Workflow for FXR1-interacting protein enrichment and proteomic characterization. d Functional enrichment of FXR1-interacting proteins. e Relative abundance of translation- (blue) and transport-related (purple) proteins identified by FXR1 Co-IP/MS. f Immunofluorescence showing FXR1 colocalization with transport or translation factors, and red arrows indicate representative colocalized puncta. g Immunofluorescent labeling combined with FISH showing colocalization of FXR1 with its target transcripts and cofactors; Images representative of three experiments. h qPCR analysis of nucleocytoplasmic ratios for pluripotency transcripts after TUBG1 or MYL12A knockdown 72 h; n = 3 independent replicates. i Puro-PLA detection of nascent nucleoporin peptides near nuclear pores following EIF5B or PABPC1 knockdown. j Quantification of perinuclear translation events from (i); NUP358 n(cell) per group = 49, 85, 54; AHCTF1 n(cell) per group = 32, 72, 49; NUP214 n(cell) per group = 36, 83, 85. Data represent the mean ± SEM. P values were determined by Student’s unpaired two-tailed t test (b, h, j); Box plots indicate median (middle line), 25th, 75th percentile (box) and 5th and 95th percentile (whiskers) as well as outliers (single points) (b, j). Source data are provided as a Source Data file.