Logo of jcellbiolHomeThe Rockefeller University PressEditorsContactInstructions for AuthorsThis issue
J Cell Biol. 1974 Apr 1; 61(1): 14–25.
PMCID: PMC2109274



Double-forked circular molecules of mitochondrial DNA (mtDNA) from rat tissues, indicated by their form and size to be replicative intermediates, are of two structurally distinct classes. Molecules of the first class are totally double stranded. Molecules of the second class are defined by one daughter segment being totally or partially single stranded. Length histograms of daughter segments measuring between 2% and 44% of the total 5-µm molecular contour were constructed from samples of both classes of replicating molecules derived from mtDNA or Novikoff rat ascites hepatoma cells. For single strand-containing molecules, the lengths fell into eight distinct, reproducible groups with mean values separated by 4.1–7.6% of the circular contour length. For totally double stranded molecules, the lengths fell into seven groups, corresponding to seven of the groups found for single strand-containing molecules. These results suggest that along at least 44% of the contour of mtDNA molecules there exist discrete points at which DNA synthesis tends to be arrested. This may indicate that there are pauses in normal mtDNA synthesis. However, as the DNA used in these experiments was isolated from mitochondrial fractions, the findings may indicate that continuation of synthesis beyond specific points on the nucleotide strands requires a factor which is not available after cell disruption.

Full Text

The Full Text of this article is available as a PDF (1.0M).

Selected References

These references are in PubMed. This may not be the complete list of references from this article.
  • Arnberg A, van Bruggen EF, Borst P. The presence of DNA molecules with a displacement loop in standard mitochondrial DNA preparations. Biochim Biophys Acta. 1971 Aug 26;246(2):353–357. [PubMed]
  • Inman RB, Schnös M. Structure of branch points in replicating DNA: presence of single-stranded connections in lambda DNA branch points. J Mol Biol. 1971 Mar 14;56(2):319–325. [PubMed]
  • Kasamatsu H, Robberson DL, Vinograd J. A novel closed-circular mitochondrial DNA with properties of a replicating intermediate. Proc Natl Acad Sci U S A. 1971 Sep;68(9):2252–2257. [PMC free article] [PubMed]
  • Kasamatsu H, Vinograd J. Unidirectionality of replication in mouse mitochondrial DNA. Nat New Biol. 1973 Jan 24;241(108):103–105. [PubMed]
  • Kirschner RH, Wolstenholme DR, Gross NJ. Replicating molecules of circular mitochondrial DNA. Proc Natl Acad Sci U S A. 1968 Aug;60(4):1466–1472. [PMC free article] [PubMed]
  • Rabinowitz M, Swift H. Mitochondrial nucleic acids and their relation to the biogenesis of mitochondria. Physiol Rev. 1970 Jul;50(3):376–427. [PubMed]
  • Richardson CC. Enzymes in DNA metabolism. Annu Rev Biochem. 1969;38:795–840. [PubMed]
  • Robberson DL, Clayton DA. Replication of mitochondrial DNA in mouse L cells and their thymidine kinase - derivatives: displacement replication on a covalently-closed circular template. Proc Natl Acad Sci U S A. 1972 Dec;69(12):3810–3814. [PMC free article] [PubMed]
  • Robberson DL, Kasamatsu H, Vinograd J. Replication of mitochondrial DNA. Circular replicative intermediates in mouse L cells. Proc Natl Acad Sci U S A. 1972 Mar;69(3):737–741. [PMC free article] [PubMed]
  • Wolstenholme DR, Koike K, Cochran-Fouts P. Single strand-containing replicating molecules of circular mitochondrial DNA. J Cell Biol. 1973 Jan;56(1):230–245. [PMC free article] [PubMed]

Articles from The Journal of Cell Biology are provided here courtesy of The Rockefeller University Press


Save items

Related citations in PubMed

See reviews...See all...

Cited by other articles in PMC

See all...


  • MedGen
    Related information in MedGen
  • PubMed
    PubMed citations for these articles
  • Substance
    PubChem Substance links

Recent Activity

Your browsing activity is empty.

Activity recording is turned off.

Turn recording back on

See more...