![]()
|
|
||||||||
J. Biol. Chem., Vol. 282, Issue 7, 4373-4381, February 16, 2007
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
From the RNA Group, Département de Microbiologie et dInfectiologie, Facultéde Médecine, Université de Sherbrooke, Sherbrooke, Québec J1H 5N4, Canada
In bakers yeast, in vivo telomerase activity requires a ribonucleoprotein (RNP) complex with at least four associated proteins (Est2p, Est1p, Est3p, and Cdc13p) and one RNA species (Tlc1). The function of telomerase in maintaining chromosome ends, called telomeres, is tightly regulated and linked to the cell cycle. However, the mechanisms that regulate the expression of individual components of telomerase are poorly understood. Here we report that yeast RNase III (Rnt1p), a double-stranded RNA-specific endoribonuclease, regulates the expression of telomerase subunits and is required for maintaining normal telomere length. Deletion or inactivation of RNT1 induced the expression of Est1, Est2, Est3, and Tlc1 RNAs and increased telomerase activity, leading to elongation of telomeric repeat tracts. In silico analysis of the different RNAs coding for the telomerase subunits revealed a canonical Rnt1p cleavage site near the 3' end of Est1 mRNA. This predicted structure was cleaved by Rnt1p and its disruption abolished cleavage in vitro. Mutation of the Rnt1p cleavage signal in vivo impaired the cell cycle-dependent degradation of Est1 mRNA without affecting its steady-state level. These results reveal a new mechanism that influences telomeres length by controlling the expression of the telomerase subunits.
Received for publication, July 27, 2006 , and in revised form, December 6, 2006.
* This work was supported by Grants MOP-67162 and MOP-74438 from the Canadian Institutes for Health Research. The costs of publication of this article were defrayed in part by the payment of page charges. This article must therefore be hereby marked "advertisement" in accordance with 18 U.S.C. Section 1734 solely to indicate this fact.
The on-line version of this article (available at http://www.jbc.org) contains supplemental Table S1 and Figs. S1S2.
1 Chercheur National of the Fonds de la Recherche en Santé du Québec.
2 Chercheur-Boursier Senior scientist. To whom correspondence should be addressed: 3001 12e Ave. Nord, Sherbrooke, Québec J1H 5N4, Canada. Tel.: 819-564-5275; Fax: 819-564-5392; E-mail: sherif.abou.elela{at}usherbrooke.ca.
![]()
CiteULike
Complore
Connotea
Del.icio.us
Digg
Reddit
Technorati What's this?
This article has been cited by other articles:
![]() |
A. D. Mozdy, E. R. Podell, and T. R. Cech Multiple Yeast Genes, Including Paf1 Complex Genes, Affect Telomere Length via Telomerase RNA Abundance Mol. Cell. Biol., June 15, 2008; 28(12): 4152 - 4161. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. Catala, M. Tremblay, E. Samson, A. Conconi, and S. Abou Elela Deletion of Rnt1p Alters the Proportion of Open versus Closed rRNA Gene Repeats in Yeast Mol. Cell. Biol., January 15, 2008; 28(2): 619 - 629. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| All ASBMB Journals | Molecular and Cellular Proteomics |
| Journal of Lipid Research | ASBMB Today |