Access

You are not currently logged in.

Access your personal account or get JSTOR access through your library or other institution:

login

Log in to your personal account or through your institution.

If You Use a Screen Reader

This content is available through Read Online (Free) program, which relies on page scans. Since scans are not currently available to screen readers, please contact JSTOR User Support for access. We'll provide a PDF copy for your screen reader.

The Second Intron of the K-ras Gene Contains Regulatory Elements Associated with Mouse Lung Tumor Susceptibility

Bin Chen, Lisa Johanson, Jonathan S. Wiest, Marshall W. Anderson and Ming You
Proceedings of the National Academy of Sciences of the United States of America
Vol. 91, No. 4 (Feb. 15, 1994), pp. 1589-1593
Stable URL: http://www.jstor.org/stable/2364147
Page Count: 5
  • Read Online (Free)
  • Subscribe ($19.50)
  • Cite this Item
Since scans are not currently available to screen readers, please contact JSTOR User Support for access. We'll provide a PDF copy for your screen reader.
The Second Intron of the K-ras Gene Contains Regulatory Elements Associated with Mouse Lung Tumor Susceptibility
Preview not available

Abstract

We have previously demonstrated the preferential activation of the K-ras gene from the susceptible A/J parent in lung tumors from F1 mouse hybrids. In the present study, the mechanism of this observation is further investigated. Higher levels of expression of A/J K-ras allele were detected in lung adenomas (30 of 30) from the C3A mouse. In addition, three K-ras alleles, designated as susceptible (Ks), intermediate (Ki), or resistant (Kr), were identified by sequence analysis of the second intron of the K-ras gene from 32 strains of mice. These K-ras alleles are associated with differences in mouse lung tumor susceptibility. All Kr alleles have a tandem 37-bp direct repeat (nt 282-355) in the second intron of the K-ras gene. Ks and Ki alleles have only one copy of the 37-bp sequence (nt 282-318). Ks strains have three base variations at nt 288, 296, and 494, and Ki strains have two base variations at nt 288 and 494 in the second intron of the K-ras gene. Differential protein-binding patterns were observed in gel-mobility-shift experiments between the duplicated 37-bp sequence of the Kr allele and the single 37-bp sequence of the Ks and Ki alleles. DNase I footprinting assay revealed protein binding sites in the second intron of the K-ras gene that correspond to the tandem repeat sequences. Our data suggest that higher expression of the A/J allele relative to C3H allele may be responsible for the allele-specific activation of the K-ras gene in lung tumors from F1 hybrid mice.

Page Thumbnails

  • Thumbnail: Page 
1589
    1589
  • Thumbnail: Page 
1590
    1590
  • Thumbnail: Page 
1591
    1591
  • Thumbnail: Page 
1592
    1592
  • Thumbnail: Page 
1593
    1593