Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 1961 Aug 1;10(4):577-87.
doi: 10.1083/jcb.10.4.577.

A METHOD FOR INTRACELLULAR AUTORADIOGRAPHY IN THE ELECTRON MICROSCOPE

M H Silk  1 , A O Hawtrey, I M Spence, J H Gear
Affiliations

A METHOD FOR INTRACELLULAR AUTORADIOGRAPHY IN THE ELECTRON MICROSCOPE

M H Silk et al. J Biophys Biochem Cytol. .

Abstract

A technic is described for high resolution intracellular autoradiography in the electron microscope. Cultures of LLC-MK(2) monkey kidney cells were incubated for 72 hours in a medium containing 0.4 microcurie per ml of thymidine-H(3). After labeling, the cells were fixed with osmium tetroxide and embedded in methacrylate. Ultrathin sections of the labeled tissue were taken up on Formvar-coated and carbon-stabilized electron microscope grids. A 150 to 450 A layer of silver metal was then evaporated onto the tissue. The coated grids were exposed to bromine vapor for 1.5 to 2 minutes under red light, allowed to dry for 1 minute, and then covered with a thin film of 1 per cent aqueous gelatin applied by means of a fine wire loop lowered over the grid supported on a glass peg. For autoradiographic exposure, the grids were stored 50 days in a light-proof container at 4 degrees C with calcium chloride desiccant. Development was carried out for 5 minutes at 20 degrees C in Promicrol (May and Baker, England) diluted 1:1 with water, followed by a 1 minute water wash and fixation for 2.5 minutes in 15 per cent aqueous sodium thiosulphate. After removal of the gelatin by immersion for 16 hours in water at 37 degrees C, the autoradiograms were dried and examined in the electron microscope. Ultrastructural detail was fairly well defined and the cytoplasm of each labeled cell was covered with an electron opaque deposit of silver, suggesting that a polynucleotide containing thymidine may be synthesized in the cytoplasm. The matter is discussed.

PubMed Disclaimer

Similar articles

See all similar articles

Cited by

References

    1. Nature. 1960 Aug 13;187:614-5 - PubMed
    1. Nature. 1959 May 23;183(4673):1461-2 - PubMed
    1. Biochem Pharmacol. 1960 Aug;4:79-85 - PubMed
    1. J Biophys Biochem Cytol. 1960 Feb;7:201-4 - PubMed
    1. Nature. 1960 Nov 5;188:511-2 - PubMed