Loss of LARP4 disrupts protein levels without affecting the mRNA abundance of mitochondrial targets. (A,B) Immunoblot validation of LARP4 depletion by CRISPR/Cas9 and analysis of various OXPHOS proteins and MRPs in HEK293 KO and parental WT cells (A; N = 4) and in U2OS KO and parental WT cells (B; N = 3). (C) Diagram of the mitochondrial, oxidative phosphorylation proteins and MRPs. (D,E) Quantification of biological replicates shown in immunoblot panels. Band intensities are normalized by a quantitative total protein stain. (F,G) Analysis of mRNA abundance in the HEK293 KO/WT cells by qPCR using probes targeting mitochondrial ribosome subunit proteins (F) or OXPHOS proteins (G). LARP4 targets are denoted with an asterisk (N = 3). All averages shown are from independent biological replicates. Statistical significance of differences was assessed by two-tailed unpaired Student's t-tests (*) P ≤ 0.05, (**) P ≤ 0.001, (***) P ≤ 0.0001. (N.S.) Not significant. See also Supplemental Figure S2.
