Skip to main content
NCBI home page
Proceedings of the National Academy of Sciences of the United States of America logoLink to Proceedings of the National Academy of Sciences of the United States of America
. 1974 Dec;71(12):5000–5003. doi: 10.1073/pnas.71.12.5000

An Altered Rate of Uridine Transport in Membrane Vesicles Isolated from Growing and Quiescent Mouse 3T3 Fibroblast Cells

Dennis C Quinlan 1, Joy Hochstadt 1
PMCID: PMC434027  PMID: 4531032

Abstract

Balb/c 3T3 and simian virus-40-transformed Balb/c 3T3 (SV-3T3) cells were examined for their ability to transport nucleosides. Confluent (quiescent) 3T3 cells transported uridine at a rate 3-4 fold lower than did subconfluent cells. Adenosine uptake was independent of cell population density. Both adenosine and uridine were transported at the same rate by confluent and sub-confluent SV-3T3 cells. A membrane vesicle population (plasma membrane and endoplasmic reticulum) was isolated from 3T3 and SV-3T3 cells by nitrogen cavitation. With membrane vesicles derived from SV-3T3 cells it was determined that uptake occurred by a mediated process. Uptake of adenosine and uridine by membrane vesicles isolated from 3T3 and SV-3T3 cells demonstrated the same pattern as found in whole cells; that is, membrane vesicles from confluent 3T3 cells transported uridine at a rate 3-fold lower than did membrane vesicles from subconfluent 3T3 cells. Much of the adenosine taken up was converted to inosine, hypoxanthine, and ribose 1-phosphate, whereas uridine transport resulted only in the accumulation of uridine. Results obtained with membrane vesicles indicate that the lowered rate of uridine transport by confluent 3T3 cells seems due to an alteration in the membrane itself or a component(s) thereof, rather than to changes in subsequent cellular metabolic processes.

Keywords: whole cell transport, mediated uptake, intravesicular transport products

Full text

PDF
5000

Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Aaronson S. A., Todaro G. J. Development of 3T3-like lines from Balb-c mouse embryo cultures: transformation susceptibility to SV40. J Cell Physiol. 1968 Oct;72(2):141–148. doi: 10.1002/jcp.1040720208. [DOI] [PubMed] [Google Scholar]
  2. Cunningham D. D., Pardee A. B. Transport changes rapidly initiated by serum addition to "contact inhibited" 3T3 cells. Proc Natl Acad Sci U S A. 1969 Nov;64(3):1049–1056. doi: 10.1073/pnas.64.3.1049. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. Ferber E., Resch K., Wallach D. F., Imm W. Isolation and characterization of lymphocyte plasma membranes. Biochim Biophys Acta. 1972 May 9;266(2):494–504. doi: 10.1016/0005-2736(72)90105-8. [DOI] [PubMed] [Google Scholar]
  4. Foster D. O., Pardee A. B. Transport of amino acids by confluent and nonconfluent 3T3 and polyoma virus-transformed 3T3 cells growing on glass cover slips. J Biol Chem. 1969 May 25;244(10):2675–2681. [PubMed] [Google Scholar]
  5. Hare J. D. Studies on the mechanism of serum stimulation of uridine uptake in serum-less mouse cells. Biochim Biophys Acta. 1972 Mar 17;255(3):905–916. doi: 10.1016/0005-2736(72)90402-6. [DOI] [PubMed] [Google Scholar]
  6. Hochstadt-Ozer J., Cashel M. The regulation of purine utilization in bacteria. V. Inhibition of purine phosphoribosyltransferase activities and purine uptake in isolated membrane vesicles by guanosine tetraphosphate. J Biol Chem. 1972 Nov 10;247(21):7067–7072. [PubMed] [Google Scholar]
  7. Hochstadt-Ozer J., Stadtman E. R. The regulation of purine utilization in bacteria. II. Adenine phosphoribosyltransferase in isolated membrane preparations and its role in transport of adenine across the membrane. J Biol Chem. 1971 Sep 10;246(17):5304–5311. [PubMed] [Google Scholar]
  8. Hochstadt-Ozer J. The regulation of purine utilization in bacteria. IV. Roles of membrane-localized and pericytoplasmic enzymes in the mechanism of purine nucleoside transport across isolated Escherichia coli membranes. J Biol Chem. 1972 Apr 25;247(8):2419–2426. [PubMed] [Google Scholar]
  9. Hochstadt J. The role of the membrane in the utilization of nucleic acid precursors. CRC Crit Rev Biochem. 1974 Mar;2(2):259–310. doi: 10.3109/10409237409105449. [DOI] [PubMed] [Google Scholar]
  10. Holley R. W. A unifying hypothesis concerning the nature of malignant growth. Proc Natl Acad Sci U S A. 1972 Oct;69(10):2840–2841. doi: 10.1073/pnas.69.10.2840. [DOI] [PMC free article] [PubMed] [Google Scholar]
  11. Kaback H. R. Regulation of sugar transport in isolated bacterial membrane preparations from Escherichia coli. Proc Natl Acad Sci U S A. 1969 Jul;63(3):724–731. doi: 10.1073/pnas.63.3.724. [DOI] [PMC free article] [PubMed] [Google Scholar]
  12. LOWRY O. H., ROSEBROUGH N. J., FARR A. L., RANDALL R. J. Protein measurement with the Folin phenol reagent. J Biol Chem. 1951 Nov;193(1):265–275. [PubMed] [Google Scholar]
  13. Weber M. J., Edlin G. Phosphate transport, nucleotide pools, and ribonucleic acid synthesis in growing and in density-inhibited 3T3 cells. J Biol Chem. 1971 Mar 25;246(6):1828–1833. [PubMed] [Google Scholar]

Articles from Proceedings of the National Academy of Sciences of the United States of America are provided here courtesy of National Academy of Sciences

RESOURCES