Journal of Molecular Biology
Volume 60, Issue 3, 28 September 1971, Pages 473-476, IN1-IN2, 477-484
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Expression of the mitochondrial genome in Hela cells: VI. Size determination of mitochondrial ribosomal RNA by electron microscopy,☆☆

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Abstract

A modified basic protein, film method of spreading RNA in a strongly denaturing solvent for examination in the electron microscope has been developed and applied to determine the size of the HeLa mitochondrial specific ribosomal RNA components. Length measurements on purified 12 s and 16 s mitochondrial rRNA, on mixtures of the two, and on mixtures of 12 s with 18 s cytoplasmic rRNA, have given molecular lengths of 0.27 μ, 0.42 μ, and 0.55 μ for the 12 s, 16 s and 18 s rRNA's. If these molecular lengths are proportional to molecular weight, and if the molecular weight of 18 s cytoplasmic rRNA is taken as 0.71 × 106, as determined by sedimentation equilibrium, the molecular weights of the 12 s and 16 s components are 0.35 × 106 and 0.54 × 106, respectively. These molecular weight values are in good agreement with the relative values predicted from sedimentation velocity measurements, but not with the relative values based on gel electrophoresis.

References (25)

  • Y. Aloni et al.

    J. Mol. Biol

    (1971)
  • F. Amaldi et al.

    J. Mol. Biol

    (1968)
  • B. Attardi et al.

    J. Mol. Biol

    (1971)
  • B. Attardi et al.

    J. Mol. Biol

    (1969)
  • D.H.L. Bishop et al.

    J. Mol. Biol

    (1967)
  • H. Boedtker

    J. Mol. Biol

    (1968)
  • P. Borst et al.

    FEBS Letters

    (1971)
  • D.T. Dubin et al.

    J. Mol. Biol

    (1970)
  • M. Edelman et al.

    J. Mol. Biol

    (1970)
  • P.H.E. Groot et al.

    Biochem. Biophys. Res. Comm

    (1970)
  • E.H. McConkey et al.

    J. Mol. Biol

    (1969)
  • I.N. Verma et al.

    J. Mol. Biol

    (1970)
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    Paper V in this series is Attardi & Ojala (1971).

    ☆☆

    This work was supported by grants GM-10991 and GM-11726 from the National Institutes of Health, by U.S. Public Health GM 00086 Training Grant to one of us (D. R.) and by a Dernham Fellowship of the American Cancer Society to another of the authors (Y. A.) Actinomycin D was a gift of Merck, Sharpe & Dohme. The φX DNA used in this investigation and the previous investigation (Robberson, Aloni & Attardi, 1971) was the kind gift of Dr J. Sedat and Mr L. Smith of Professor R. L. Sinsheimer's laboratory.

    Present address: Dept. of Pathology, Stanford University Medical School, Stanford, Calif. 94305 U.S.A.

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