Fig. 4: Co-translational substrate recognition is modular.
From: Co-translational assembly orchestrates competing biogenesis pathways
a RIP-qPCR experiments with Sec13, Sec31, Nup145C, and Mtc5 as baits. Bar graphs depict mean ± SD. n = 6 biologically independent samples for Sec31-StepII (sec13- and sec31-mRNA) and Nup145C-StepII (sec13- and nup145-mRNA) and n = 4 biologically independent samples for Sec13-StepII (sec13-, sec31-, nup145- and mtc5-mRNA) and Mtc5-StepII (sec13- and mtc5-mRNA). **p = 0.004 for Sec31-StepII (sec31-mRNA). b SeRP analysis of Sec13 and Sec31 from n = 3 biologically independent replicates. c Sec13 recognizes the domain invasion motif of Sec31 (highlighted as transparent isosurface) in a co-translational manner d, Sec31-Sec31 dimerization occurs after release of the entire alpha-solenoid interaction surface (highlighted as transparent isosurface) from the exit channel of the ribosome. Structures in c, and d, are taken from 4BZK62. e The co-translational interaction of Sec13 with nascent Sec16 occurs subsequent to the synthesis of alpha-helices located below the beta-propeller of Sec13 that are highlighted as transparent isosurface (PDB: 3MZK51). f, Superposition of the domain invasion motifs of Sec16 and Sec31 within Sec13 (PDB: 4BZK, 3MZK). ns p > 0.05, *p < 0.05, **p < 0.01 (Two-sided, paired t-test). Source data for RIP-qPCR in panel a, are provided as a Source Data file. AA amino acid, IP immunoprecipitation, DIM domain invasion motif.
