ATR Kinase Is a Crucial Player Mediating the DNA Damage Response in Trypanosoma brucei

Autor(es)

Marin, Paula Andrea ; Obonaga, Ricardo ; Pavani, Raphael Souza ; da Silva, Marcelo Santos ; de Araujo, Christiane Bezerra ; Lima, Andre Arruda ; Avila, Carla Cristi ; Cestari, Igor ; Machado, Carlos Renato ; Elias, Maria Carolina

• Tipo de documento: Artigo Científico
• Fonte: FRONTIERS IN CELL AND DEVELOPMENTAL BIOLOGY; v. 8, p. 18-pg., 2020-12-22.

Resumo

DNA double-strand breaks (DSBs) are among the most deleterious lesions that threaten genome integrity. To address DSBs, eukaryotic cells of model organisms have evolved a complex network of cellular pathways that are able to detect DNA damage, activate a checkpoint response to delay cell cycle progression, recruit the proper repair machinery, and resume the cell cycle once the DNA damage is repaired. Cell cycle checkpoints are primarily regulated by the apical kinases ATR and ATM, which are conserved throughout the eukaryotic kingdom. Trypanosoma brucei is a divergent pathogenic protozoan parasite that causes human African trypanosomiasis (HAT), a neglected disease that can be fatal when left untreated. The proper signaling and accuracy of DNA repair is fundamental to T. brucei not only to ensure parasite survival after genotoxic stress but also because DSBs are involved in the process of generating antigenic variations used by this parasite to evade the host immune system. DSBs trigger a strong DNA damage response and efficient repair process in T. brucei, but it is unclear how these processes are coordinated. Here, by knocking down ATR in T. brucei using two different approaches (conditional RNAi and an ATR inhibitor), we show that ATR is required to mediate intra-S and partial G1/S checkpoint responses. ATR is also involved in replication fork stalling, is critical for H2A histone phosphorylation in a small group of cells and is necessary for the recruitment and upregulation of the HR-mediated DNA repair protein RAD51 after ionizing radiation (IR) induces DSBs. In summary, this work shows that apical ATR kinase plays a central role in signal transduction and is critical for orchestrating the DNA damage response in T. brucei. (AU)

• Processo FAPESP: 14/02978-0 - Análise funcional do complexo RPA em Trypanosoma cruzi e seu envolvimento com DNA telomérico
• Beneficiário: Raphael Souza Pavani
• Modalidade de apoio: Bolsas no Brasil - Doutorado
• Processo FAPESP: 14/24170-5 - Dinâmica da replicação do DNA em Trypanosoma cruzi: caracterização do licenciamento e da taxa de replicação
• Beneficiário: Marcelo Santos da Silva
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado
• Processo FAPESP: 14/13375-5 - Origens da replicação em tripanossomas
• Beneficiário: Christiane Bezerra de Araujo
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado
• Processo FAPESP: 18/12364-0 - Expressão, purificação e caracterização inicial de uma nova proteína RPA-like de Trypanosoma brucei
• Beneficiário: André Arruda Lima
• Modalidade de apoio: Bolsas no Brasil - Iniciação Científica
• Processo FAPESP: 19/01895-8 - Função das nucleases MRE11, DNA2 e EXO1 na ressecção do DNA terminal e o reparo das quebras de dupla fita em Trypanosoma brucei
• Beneficiário: Ricardo Obonaga Gómez
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado
• Processo FAPESP: 16/50050-2 - How do common and diverged features of the replicative stress response shape the biology of TriTryp parasites?
• Beneficiário: Maria Carolina Quartim Barbosa Elias Sabbaga
• Modalidade de apoio: Auxílio à Pesquisa - Temático
• Processo FAPESP: 17/18719-2 - Análise estrutural do complexo de reconhecimento de origens de replicação (ORC) em Trypanosoma brucei utilizando cryo-electron microscopy e single-particle analysis
• Beneficiário: Marcelo Santos da Silva
• Modalidade de apoio: Bolsas no Exterior - Estágio de Pesquisa - Pós-Doutorado
• Processo FAPESP: 15/10580-0 - Caracterização de checkpoint intra-S em células de Trypanosoma
• Beneficiário: Maria Carolina Quartim Barbosa Elias Sabbaga
• Modalidade de apoio: Auxílio à Pesquisa - Regular