Phenotypic suppression of the Drosophila mitochondrial disease-like mutant tko(25t) by duplication of the mutant gene in its natural chromosomal context

Mitochondrion. 2009 Sep;9(5):353-63. doi: 10.1016/j.mito.2009.07.002. Epub 2009 Jul 17.


A mutation in the Drosophila gene technical knockout (tko(25t)), encoding mitoribosomal protein S12, phenocopies human mitochondrial disease. We isolated three spontaneous X-dominant suppressors of tko(25t) (designated Weeble), exhibiting almost wild-type phenotype and containing overlapping segmental duplications including the mutant allele, plus a second mitoribosomal protein gene, mRpL14. Ectopic, expressed copies of tko(25t) and mRpL14 conferred no phenotypic suppression. When placed over a null allele of tko, Weeble retained the mutant phenotype, even in the presence of additional transgenic copies of tko(25t). Increased mutant gene dosage can thus compensate the mutant phenotype, but only when located in its normal chromosomal context.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Drosophila / genetics*
  • Female
  • Gene Dosage
  • Gene Duplication*
  • Humans
  • Male
  • Mitochondrial Diseases / genetics*
  • Mitochondrial Proteins / genetics*
  • Ribosomal Proteins / genetics*
  • Suppression, Genetic*


  • Mitochondrial Proteins
  • Ribosomal Proteins
  • mitochondrial ribosomal protein S12