Biogenesis of mitochondria 44

✍ Scribed by Trembath, M. K. ;Molloy, P. L. ;Sriprakash, K. S. ;Cutting, G. J. ;Linnane, A. W. ;Lukins, H. B.

• Publisher: Springer
• Year: 1976
• Tongue: English
• Weight: 964 KB
• Volume: 145
• Category: Article
• ISSN: 0026-8925
• DOI: 10.1007/bf00331556

✦ Synopsis

A comparative study of eight independently isolated mitochondrial oligomycin resistant mutants obtained from three laboratories show a variety of phenotypes based on cross resistance to venturicidin and sensitivity to low temperature. Analysis of recombination between pairs of markers indicate the existence of at least three genetic classes; class A, cross resistant to venturicidin and including the mutations OIII, [olil-r], [olgi-R], [tso-r]; class B, mutations OI, [olil7-r], [OLG2-R]; and class C, the mutation O11. The recombination data is consistent with mutations of each class residing in three separate genes, although mutations of class A and B show very close linkage. Recombination in non-polar crosses had demonstrated that markers of all three classes are linked to the mikl locus in the configuration (AB)-mikl-C. The mapping of this segment with respect to other markers of the mitochondrial genome and the order of classes A and B was established by analysis of co-retention frequenceis of markers in primary petite isolates as well as by analysis of marker overlap of genetically and physically defined petite genomes. The unambiguous order eryl-A-B-mik1-C-par was obtained. DNA-DNA hybridization studies using mtDNA isolated from selected petites confirms this map and estimates the physical separation of markers. A resonable correlation exists in this region of th genome between distances estimated physically by hybridization and genetically by frequencey of recombination in non-polar crosses. It is potulated that the oligomycin-mikamycin linkage group represents a cluster of genes involved in determing a number of mitochondrial membrane proteins associated with the mitochondrial ATPase and respiratory complex III.