Journal: Cells
Article Title: TFAM’s Contributions to mtDNA Replication and OXPHOS Biogenesis Are Genetically Separable
doi: 10.3390/cells11233754
Figure Lengend Snippet: The domain organization of the human TFAM and GeneSwap approach. ( A ) The domain structure of human TFAM. The bold upward vertical arrow designates a crossover point in chimeras (between residues 154 and 155 of the hTFAM). Here, we refer to the TFAM portion preceding the crossover point as the N-terminal domain (NTD) and the following portion C-terminal domain (CTD). Subdomain boundaries are given in aa coordinates. MTS, matrix targeting sequence. ( B ) Derivation of the hTFAM GeneSwap cell line 143B#6. In 143B osteosarcoma cells, TFAM was inactivated with CRISPR/Cas9 and replaced with a retrovirus-encoded, loxP-site-flanked wt TFAM cDNA. To reintroduce mtDNA, the resulting cells were fused with chemically enucleated MDA-MB-231 cells, resulting in the 143B#6 cell line (9). ( C ) Schematics of the GeneSwap approach. To implement GeneSwap, 143B#6 cells (top panel) were co-transduced with retroviruses encoding Cre recombinase and altered TFAM (TFAMvar, central panel). This results in the excision of the wtTFAM cDNA and simultaneous re-expression of TFAMvar. In the resulting cotransductants, mtDNA is retained only if TFAMvar is functional in hmtDNA replication. In that case, the functionality is further validated by transducing cells with PhiC31 recombinase, which affects the loss of TFAMvar and hmtDNA (the bottom panel).
Article Snippet: PhiC31 recombinase for excision of chTFAM variants was delivered with rv.5136, which also encodes hygromycin resistance ( , Addgene no. 184853).
Techniques: Sequencing, CRISPR, Transduction, Expressing, Functional Assay