Mitotic segregation of cytoplasmic determinants for chloramphenicol resistance in mammalian cells. I: Fusion with mouse cell lines

Somatic Cell Genet. 1977 Jan;3(1):71-92. doi: 10.1007/BF01550988.


The segregation of cytoplasmically inherited chloramphenicol (CAP) resistance in mouse cells was investigated in fusions between CAP-resistant cells or cytoplasts (enucleated cells) and CAP-sensitive cells of varying tissue origin. All hybrids formed in cell-cell fusions were initially CAP-resistant, indicating that CAP resistance is dominant. Hybrids from fusions of cells of the same tissue origin (homologous) were stably CAP-resistant, whereas the hybrid population from fusions of different origins (heterologous) showed a rapid diminution of average CAP resistance. Individual hybrid clones from these heterologous fusions also showed an overall loss of CAP resistance, and a wide variation in CAP resistance which is consistent with a large number of genetic determinants (possibly mitochondrial DNA molecules) contributing to the CAP phenotype. Similar results were obtained from cytoplast-cell fusions, so the observed CAP segregation is not the result of nuclear-nuclear interactions. This segregation of CAP resistance constitutes a second criterion of cytoplasmic inheritance in mammalian cells.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Animals
  • Cell Line
  • Chloramphenicol / pharmacology*
  • Drug Resistance*
  • Extrachromosomal Inheritance*
  • Genes
  • Hybrid Cells
  • Mice
  • Mitochondria
  • Mitosis


  • Chloramphenicol