- THIS ARTICLE
- Full Text (PDF)
- Alert me when this article is cited
- Alert me if a correction is posted
- SERVICES
- Similar articles in this journal
- Similar articles in PubMed
- Alert me to new issues of the journal
- Download to citation manager
- Reprints & Permissions
- CITING ARTICLES
- Citing Articles via HighWire
- Citing Articles via Google Scholar
- GOOGLE SCHOLAR
- Articles by Ciampi, M. S.
- Articles by Roth, J. R.
- Search for Related Content
- PUBMED
- PubMed Citation
- Articles by Ciampi, M. S.
- Articles by Roth, J. R.
Genetics, Vol 118, 193-202, Copyright © 1988
INVESTIGATIONS |
Polarity Effects in the hisG Gene of Salmonella Require a Site Within the Coding Sequence
M. S. Ciampi and J. R. Roth
Present address: Istituto di Genetica, Universita di Bari, 70127 Bari, Italy.
A single site in the middle of the coding sequence of the hisG gene of Salmonella is required for most of the polar effect of mutations in this gene. Nonsense and insertion mutations mapping upstream of this point in the hisG gene all have strong polar effects on expression of downstream genes in the operon; mutations mapping promotor distal to this site have little or no polar effect. Two previously known hisG mutations, mapping in the region of the polarity site, abolish the polarity effect of insertion mutations mapping upstream of this region. New polarity site mutations have been selected which have lost the polar effect of upstream nonsense mutations. All mutations abolishing the function of the site are small deletions; three are identical, 28-bp deletions which have arisen independently. A fourth mutation is a deletion of 16 base pairs internal to the larger deletion. Several point mutations within this 16-bp region have no effect on the function of the polarity site. We believe that a small number of polarity sites of this type are responsible for polarity in all genes. The site in the hisG gene is more easily detected than most because it appears to be the only such site in the hisG gene and because it maps in the center of the coding sequence.
This article has been cited by other articles:
 |
|
 |
|
  M. S. Ciampi Rho-dependent terminators and transcription termination. Microbiology, September 1, 2006; 152(Pt 9): 2515 - 2528. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 A. Rubio and D. M. Downs Elevated Levels of Ketopantoate Hydroxymethyltransferase (PanB) Lead to a Physiologically Significant Coenzyme A Elevation in Salmonella enterica Serovar Typhimurium J. Bacteriol., May 15, 2002; 184(10): 2827 - 2832. [Abstract] [Full Text] [PDF]
|
|