PT  - JOURNAL ARTICLE
AU  - Marcelo S. da Silva
AU  - Gustavo R. Cayres-Silva
AU  - Marcela O. Vitarelli
AU  - Paula A. Marin
AU  - Priscila M. Hiraiwa
AU  - Christiane B. Araújo
AU  - Andrea R. Ávila
AU  - Marcelo S. Reis
AU  - Maria Carolina Elias
TI  - Transcription activity contributes to the firing of non-constitutive origins in <em>Trypanosoma brucei</em>
AID  - 10.1101/398016
DP  - 2018 Jan 01
TA  - bioRxiv
PG  - 398016
4099  - http://biorxiv.org/content/early/2018/09/03/398016.short
4100  - http://biorxiv.org/content/early/2018/09/03/398016.full
AB  - The cosynthesis of DNA and RNA potentially generates conflicts between replication and transcription, which can lead to genomic instability. In trypanosomatids, eukaryotic parasites that perform polycistronic transcription, this phenomenon and its consequences have not yet been investigated. Here, using equations and computational analysis we demonstrated that the number of constitutive origins mapped in the Trypanosoma brucei genome is close to the minimum required to complete replication within S phase duration. However, taking into account the location of these origins in the genome, the replication in due time becomes virtually impossible, making it necessary to activate non-constitutive origins. Moreover, computational and biological assays pointed to transcription being responsible for activating non-constitutive origins. Together, our results suggest that transcription action through conflicts with replication contributes to the firing of non-constitutive origins, maintaining the robustness of S phase duration. The usage of this entire pool of origins seems to be of paramount importance for the survival of this parasite that infects million people around the world since it contributes to the maintenance of the replication of its DNA.