Skip Navigation

This Article
Right arrow Print PDF (4662K)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Add to My Personal Archive
Right arrow Download to citation manager
Right arrow Commercial Re-use Guidelines
for Open Access NAR Content
Google Scholar
Right arrow Articles by Gerhold, D.
Right arrow Articles by Kmiec, E. B.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Gerhold, D.
Right arrow Articles by Kmiec, E. B.
Social Bookmarking
Add to CiteULike   Add to Connotea   Add to Del.icio.us  
What's this?

Nucleic Acids Research, 1994, Vol. 22, No. 18 3773-3778
© 1994

MOLECULAR BIOLOGY

The topoisomerase I gene from Ustilago maydis: sequence, disruption and mutant phenotype

David Gerhold, Manimekalai Thiyagarajan and Eric B. Kmiec*

Department of Pharmacology, Jefferson Cancer Institute, Thomas Jefferson University 233 S. 10th Street, Philadelphia, PA 19107, USA

*To whom correspondence should be addressed

Received May 3, 1994. Revised July 26, 1994. Accepted July 26, 1994.

The Ustilago maydis genomic TOP1 gene encoding DNA topoisomerase I was cloned by amplifying a gene fragment using the polymerase chain reaction, and using this fragment to search a genomic DNA library by hybridization. The predicted peptide sequence exhibited 30–40% identity to other eukaryotic TOP1 genes, yet differed in several features. First, an unusually long acidic region was identified near the amino terminus (28/29 residues are acidic), which resembles other nucleolar peptide motifs. Second, an atypical carboxy-terminal 'tail', absent in other TOP1 genes, followed the active site tyrosine residue. A top1 gene disruption mutant was constructed by replacing the genomic TOP1 gene, with a top1::HygR null allele. This mutant lost the abundant topoisomerase I activity evident in wild-type U.maydis, and displayed a subtle coloration phenotype evident during cell senescence.


Add to CiteULike CiteULike   Add to Connotea Connotea   Add to Del.icio.us Del.icio.us    What's this?


This article has been cited by other articles:


Home page
 GeneticsHome page
M. Del Poeta, D. L. Toffaletti, T. H. Rude, C. C. Dykstra, J. Heitman, and J. R. Perfect
Topoisomerase I Is Essential in Cryptococcus neoformans: Role in Pathobiology and as an Antifungal Target
Genetics, May 1, 1999; 152(1): 167 - 178.
[Abstract] [Full Text]

Home page
 J. Biol. Chem.Home page
B. O. Petersen and S. Shuman
Histidine 265Is Important for Covalent Catalysis by Vaccinia Topoisomerase and Is Conserved in All Eukaryotic Type I Enzymes
J. Biol. Chem., February 14, 1997; 272(7): 3891 - 3896.
[Abstract] [Full Text] [PDF]


Disclaimer:
Please note that abstracts for content published before 1996 were created through digital scanning and may therefore not exactly replicate the text of the original print issues. All efforts have been made to ensure accuracy, but the Publisher will not be held responsible for any remaining inaccuracies. If you require any further clarification, please contact our Customer Services Department.