Journal Mobile Options
Table of Contents
Vol. 24, No. 3, 1978
Issue release date: 1978
Gerontology 1978;24:179–207

Age-Related Differences in the Number of Ribosomal RNA Genes of Mouse Tissues

Gaubatz J.W. · Cutler R.G.
Laboratory of Cellular and Comparative Physiology, Gerontology Research Center, National Institute on Aging, National Institutes of Health, PHS, US Department of Health, Education and Welfare, Bethesda and Baltimore City Hospitals, Baltimore, Md.

Individual Users: Register with Karger Login Information

Please create your User ID & Password

Contact Information

I have read the Karger Terms and Conditions and agree.

To view the fulltext, please log in

To view the pdf, please log in


An age-related change in DNA sequences coding for rRNA was investigated by: (1) hybridizing DNA with an excess of rRNA to assay for quantitative changes in rRNA gene dosage, and (2) examining physiochemical properties of rRNA·DNA hybrids to determine possible qualitative changes in informational content. The rRNA gene dosage (as estimated by the amount of rRNA able to hybridize to total DNA) was determined in liver, brain, kidney and spleen tissues throughout the life span of female mice from the C57BL/6J inbred mouse strain. The rRNA gene dosage (number of genes per haploid genome) is 100–110 genes in all tissues up to 800 days, with the exception of liver tissue. Liver tissue in mice 10–200 days old contains only about 85 genes. Between the ages of 200–350 days, however, the rRNA gene dosage of liver cells increased to a level equal to that found for other tissues. Past 800 days, a decrease in rRNA gene dosage is observed for all tissues examined. The decrease ranges from 9 to 44%, depending upon the age and tissue investigated. Total mouse embryo also exhibits a low rRNA gene dosage, which is similar to that found for young mouse liver. As a function of age, no substantial changes were detected in the physiochemical properties of the rRNA•DNA hybrid, as measured by thermal stability, sensitivity to RNase treatment, or hybridization kinetics. Decreases in the rRNA hybridization level found for the very old mice may reflect an actual loss of the genes or an inhibition of hybridization due to an age-dependent accumulation of cross-linked chromosomal proteins or other DNA-adducts at the rRNA gene loci. Recovery of hybridization, after an extensive deproteinization treatment of single-stranded DNA, supports this latter interpretation.

Copyright / Drug Dosage

Copyright: All rights reserved. No part of this publication may be translated into other languages, reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying, recording, microcopying, or by any information storage and retrieval system, without permission in writing from the publisher or, in the case of photocopying, direct payment of a specified fee to the Copyright Clearance Center.
Drug Dosage: The authors and the publisher have exerted every effort to ensure that drug selection and dosage set forth in this text are in accord with current recommendations and practice at the time of publication. However, in view of ongoing research, changes in goverment regulations, and the constant flow of information relating to drug therapy and drug reactions, the reader is urged to check the package insert for each drug for any changes in indications and dosage and for added warnings and precautions. This is particularly important when the recommended agent is a new and/or infrequently employed drug.
Disclaimer: The statements, opinions and data contained in this publication are solely those of the individual authors and contributors and not of the publishers and the editor(s). The appearance of advertisements or/and product references in the publication is not a warranty, endorsement, or approval of the products or services advertised or of their effectiveness, quality or safety. The publisher and the editor(s) disclaim responsibility for any injury to persons or property resulting from any ideas, methods, instructions or products referred to in the content or advertisements.

Pay-per-View Options
Direct payment This item at the regular price: USD 38.00
Payment from account With a Karger Pay-per-View account (down payment USD 150) you profit from a special rate for this and other single items.
This item at the discounted price: USD 26.50