This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Supplemental material
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Right arrow Citation Map
Services
Right arrow E-mail 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 Download to citation manager
Right arrowReprints and Permissions
Right arrow Copyright Information
Right arrow Books from ASM Press
Right arrow MicrobeWorld
Citing Articles
Right arrow Citing Articles via HighWire
Google Scholar
Right arrow Articles by Godoy, P. D. d. M.
Right arrow Articles by Elias, M. C.
PubMed
Right arrow PubMed Citation
Right arrow Articles by Godoy, P. D. d. M.
Right arrow Articles by Elias, M. C.

 Previous Article  |  Next Article 

Eukaryotic Cell, October 2009, p. 1592-1603, Vol. 8, No. 10
1535-9778/09/$08.00+0     doi:10.1128/EC.00161-09
Copyright © 2009, American Society for Microbiology. All Rights Reserved.

Trypanosome Prereplication Machinery Contains a Single Functional Orc1/Cdc6 Protein, Which Is Typical of Archaea{triangledown} ,{dagger}

Patrícia Diogo de Melo Godoy,1 Luis Antonio Nogueira-Junior,1 Lisvane S. Paes,2 Alberto Cornejo,3 Rafael Miyazawa Martins,3 Ariel M. Silber,2 Sergio Schenkman,3 and M. Carolina Elias1*

Laboratório de Parasitologia, Instituto Butantan, São Paulo, Brazil,1 Departamento de Parasitologia, Universidade de São Paulo, São Paulo, Brazil,2 Departamento de Microbiologia, Imunologia e Parasitologia, Universidade Federal de São Paulo, São Paulo, Brazil3

Received 5 June 2009/ Accepted 19 August 2009

In unicellular eukaryotes, such as Saccharomyces cerevisiae, and in multicellular organisms, the replication origin is recognized by the heterohexamer origin recognition complex (ORC) containing six proteins, Orc1 to Orc6, while in members of the domain Archaea, the replication origin is recognized by just one protein, Orc1/Cdc6; the sequence of Orc1/Cdc6 is highly related to those of Orc1 and Cdc6. Similar to Archaea, trypanosomatid genomes contain only one gene encoding a protein named Orc1. Since trypanosome Orc1 is also homologous to Cdc6, in this study we named the Orc1 protein from trypanosomes Orc1/Cdc6. Here we show that the recombinant Orc1/Cdc6 from Trypanosoma cruzi (TcOrc1/Cdc6) and from Trypanosoma brucei (TbOrc1/Cdc6) present ATPase activity, typical of prereplication machinery components. Also, TcOrc1/Cdc6 and TbOrc1/Cdc6 replaced yeast Cdc6 but not Orc1 in a phenotypic complementation assay. The induction of Orc1/Cdc6 silencing by RNA interference in T. brucei resulted in enucleated cells, strongly suggesting the involvement of Orc1/Cdc6 in DNA replication. Orc1/Cdc6 is expressed during the entire cell cycle in the nuclei of trypanosomes, remaining associated with chromatin in all stages of the cell cycle. These results allowed us to conclude that Orc1/Cdc6 is indeed a member of the trypanosome prereplication machinery and point out that trypanosomes carry a prereplication machinery that is less complex than other eukaryotes and closer to archaea.

* Corresponding author. Mailing address: Laboratório de Parasitologia, Instituto Butantan, Av. Vital Brasil, 1500, São Paulo 05503900, Brazil. Phone: (55 11) 3726-7222, ext. 2158. E-mail: carol{at}butantan.gov.br

{triangledown} Published ahead of print on 28 August 2009.

{dagger} Supplemental material for this article may be found at http://ec.asm.org/.

Eukaryotic Cell, October 2009, p. 1592-1603, Vol. 8, No. 10
1535-9778/09/$08.00+0     doi:10.1128/EC.00161-09
Copyright © 2009, American Society for Microbiology. All Rights Reserved.



This article has been cited by other articles:

  • Cavalier-Smith, T. (2009). Kingdoms Protozoa and Chromista and the eozoan root of the eukaryotic tree. Biol Lett 0: rsbl.2009.0948v1-rsbl20090948 [Abstract] [Full Text]  


Copyright © 2010 by the American Society for Microbiology.   For an alternate route to Journals.ASM.org, visit: http://intl-journals.asm.org | More Info»