Lookup NU author(s): Dr Thomas Nicholls,
Professor Patrick Chinnery
This work is licensed under a Creative Commons Attribution 4.0 International License (CC BY 4.0).
Somatic mutations in the mitochondrial genome (mtDNA) have been linked to multiple disease conditions and to ageing itself. In Drosophila, knock-in of a proofreading deficient mtDNA polymerase (POLG) generates high levels of somatic point mutations and also small indels, but surprisingly limited impact on organismal longevity or fitness. Here we describe a new mtDNA mutator model based on a mitochondrially-targeted cytidine deaminase, APOBEC1. mito-APOBEC1 acts as a potent mutagen which exclusively induces C:G>T:A transitions with no indels or mtDNA depletion. In these flies, the presence of multiple non-synonymous substitutions, even at modest heteroplasmy, disrupts mitochondrial function and dramatically impacts organismal fitness. A detailed analysis of the mutation profile in the POLG and mito-APOBEC1models reveals that mutation type (quality) rather than quantity is a critical factor in impacting organismal fitness. The specificity for transition mutations and the severe phenotypes make mito-APOBEC1 an excellent mtDNA mutator model for ageing research.
Author(s): Andreazza S, Samstag CL, Sanchez-Martinez A, Fernandez-Vizarra E, Gomez-Duran A, Lee JJ, Tufi R, Hipp MJ, Schmidt EK, Nicholls TJ, Gammage PA, Chinnery PF, Minczuk M, Pallanck LJ, Kennedy SR, Whitworth AJ
Publication type: Article
Publication status: Published
Journal: Nature Communications
Online publication date: 23/07/2019
Acceptance date: 06/06/2019
Date deposited: 25/07/2019
ISSN (electronic): 2041-1723
Publisher: Nature Publishing Group
PubMed id: 31337756
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