Article
- The EMBO Journal (2003) 22, 4866 - 4875
- doi:10.1093/emboj/cdg450
There is an Erratum (November 2003) associated with this Article.
Subject Categories:
A new retroelement constituted by a natural alternatively spliced RNA of murine replication-competent retroviruses
Laurent Houzet1,2, Jean Luc Battini1, Eric Bernard2, Valerie Thibert1 and Marylène Mougel1,2
- Group 'RNA Metabolism and Retroviral Replication' of UMR5555 CNRS, Montpellier, France
- Group 'RNA Metabolism and Retroviral Replication', Department of 'Infections Rétrovirales et Signalisation Cellulaire', UMR5121 CNRS, UMI, IFR122, 4 Boulevard Henri IV, CS89508, 34960 Montpellier, France
Correspondence to:
Marylène Mougel, E-mail: marylene.mougel@univ-montp1.fr
Received 1 October 2002; Accepted 23 July 2003; Revised 7 July 2003
Abstract
Replication of simple retroviruses depends on the recruitment of a single large primary transcript toward splicing, transport/packaging and translation regulations. In this respect, we studied the novel SD' 4.4 kb RNA of murine leukemia retroviruses (MLV) which results from alternative splicing of the primary transcript. We showed that SD' RNA was required for optimal replication since expression of a pre spliced SD' RNA trans-complemented the impaired infectivity of a SD'-defective mutant. We monitored the fate of this novel transcript throughout early and late events of the viral life cycle. SD' RNA was specifically incorporated into virions demonstrating that the unspliced RNA was not the unique viral RNA present in virions. Furthermore, SD' RNA was reverse transcribed and its DNA copy integrated into the host genome, thus constituting a new splice donor-associated retroelement (SDARE) in infected cells. Finally, we showed that SD' mRNA encoded a 50 kDa polyprotein, and to a lower extent an additional 60 kDa polyprotein, which harbored Gag and integrase domains.
Keywords:
- defective retrovirus,
- Gag translation,
- RNA encapsidation,
- viral RNA splicing,
- virion assembly
