Retrotransposons. An RNA polymerase III subunit determines sites of retrotransposon integration.

Antoine Bridier-Nahmias (1) , Aurélie Tchalikian-Cosson (1) , Joshua A Baller (2) , Rachid Menouni (1) , Hélène Fayol (1) , Amando Flores (3, 4) , Ali Saïb (1) , Michel Werner (5, 3, 4) , Daniel F Voytas (2) , Pascale Lesage (1)

1 Pathologie cellulaire : aspects moléculaires et viraux / Pathologie et Virologie Moléculaire
2 Department of Genetics, Cell Biology and Development
3 I2BC - Institut de Biologie Intégrative de la Cellule
4 IBITECS - Institut de Biologie et de Technologies de Saclay
5 GTR - Régulation transcriptionnelle des génomes

Mobile genetic elements are ubiquitous. Their integration site influences genome stability and gene expression. The Ty1 retrotransposon of the yeast Saccharomyces cerevisiae integrates upstream of RNA polymerase III (Pol III)-transcribed genes, yet the primary determinant of target specificity has remained elusive. Here we describe an interaction between Ty1 integrase and the AC40 subunit of Pol III and demonstrate that AC40 is the predominant determinant targeting Ty1 integration upstream of Pol III-transcribed genes. Lack of an integrase-AC40 interaction dramatically alters target site choice, leading to a redistribution of Ty1 insertions in the genome, mainly to chromosome ends. The mechanism of target specificity allows Ty1 to proliferate and yet minimizes genetic damage to its host.

Domaines: Sciences du Vivant [q-bio]

Antoine Bridier-Nahmias, Aurélie Tchalikian-Cosson, Joshua A Baller, Rachid Menouni, Hélène Fayol, et al.. Retrotransposons. An RNA polymerase III subunit determines sites of retrotransposon integration.. Science, 2015, pp.585-8. ⟨10.1126/science.1259114⟩. ⟨hal-01464742⟩