Allele-Specific Replication Inhibition of Mitochondrial DNA by MITO-PIP Conjugated with Alkylation Reagent

Abstract

Pathogenic mutations in mitochondrial DNA cause genetic disorders named mitochondrial diseases. Although mutated mitochondrial DNA should be eliminated from cells, no chemical-based drugs in clinical trials have the potential to modulate mtDNA mutation and cure mitochondrial diseases permanently. To achieve selective elimination of mitochondrial DNA with mutant adenine base, I develop a conjugate of MITO-PIP and chlorambucil (Chb), which can alkylate an adenine base in a sequence-specific manner. The in vitro alkylation assay shows that a conjugate targeting the point mutation in HeLa S3 cells (m.8950G > A) alkylates the adenine at the mutation site. The conjugate also reduces the proportion of mutant mtDNA in cultured HeLa S3 cells. MITO-PIP–Chb conjugates would be drug candidates to cure mitochondrial diseases caused by pathogenic mutations in mtDNA and paves the way to the gene therapy of mitochondrial diseases by a chemical approach.KeywordsMitochondrial DNAMitochondrial diseasesDNA mutationDNA alkylation