Figure 1.

(A) Routes for mitochondrial protein import. In post-translational import, proteins are imported to mitochondria after their complete synthesis in the cytosol in a process aided by chaperones and co-chaperones. Whereas the localized translation that occurs at the surface of mitochondria may be directly coupled with the translocation of proteins into organelle. (B) Biochemical fractionation of 5 days post fertilization zebrafish larvae based on strategy to obtain intact mitochondria with associated ribosomes in yeast (Gold et al, 2017). Isolation of mitochondria with associated ribosomes was performed using a ribosome-friendly buffer (IB-M) containing MgCl₂, cycloheximide, and RNAse inhibitors. MB and HS fractions were obtained via differential centrifugation. Total RNA isolated from each fraction was enriched for polyadenylated fraction and subjected to short-read sequencing using Illumina platform. (C) Isolation of membrane-bound and high speed fractions. (D) qRT-PCR validation of MB fraction. Relative enrichment of genes in MB with respect to EDTA-stripped MB upon normalization with mitochondrial DNA encoded mt-atp8 is shown. Data derived from three biological replicates. Error bars correspond to SEM; P < 0.05 (*), P < 0.01 (**), and P < 0.0001 (****) by unpaired t test.