Extended Data Fig. 7: Subcellular transcriptome distribution follows mTOR dependence.

a, Sample transcripts from each class represented in Fig. 4 were verified by qPCR (y axis), and correlated with RNA-seq mapping values (x axis). Measurements from the two approaches displayed strong concurrence, with correlation coefficient R² = 0.736. Centre points denote the mean, and error bars denote s.e.m. of three biological replicates from independent litters. Colour legend and schematics of mRNA classes based on known mTOR dependence: mRNAs containing a TOP motif are mTOR-dependent (green); schema indicates direct binding of the TOP motif by LARP1, which interacts with mTOR. mRNAs containing internal ribosome entry sites or lacking poly(A) tails are mTOR-independent (blue). Canonical mRNAs that undergo cap-dependent translation (grey) display moderate responses to mTOR. c, Expanded dataset presented in Fig. 4c. Single-molecule RNA chromogenic in situ hybridization (ISH, red) of two TOP transcripts: Rack1 (non-ribosomal TOP) and Rplp0 (ribosomal TOP), compared to a control transcript Ppib (soma-mapped canonical) in callosal projection neurons. Neurons were labelled with mem-GFP (green) via in utero electroporation at embryonic day (E) 15, cultured at P0, fixed and hybridized at in vitro day (DIV) 2–3. Nuclei were stained with DAPI (blue). Soma and GC close-ups shown in insets as overlays of transcript (red) with mem-GFP (green) in top rows, or with traced GC outlines in bottom rows. 92, 103 and 84 GCs imaged for Rack1, Rplp0 and Ppib probes, respectively, from n = 4 biological replicates from independent in utero electroporations. Five example GCs are shown per sample to capture the representative range. Scale bars, 10 μm.