| Autor: |
Chame DF; Universidade Federal de Minas Gerais, Instituto de Ciências Biológicas, Departamento de Bioquímica e Imunologia, Avenida Antônio Carlos, 6627, 31270-901 Belo Horizonte, MG, Brazil., Laet-Souza D; Universidade Federal de Minas Gerais, Instituto de Ciências Biológicas, Departamento de Bioquímica e Imunologia, Avenida Antônio Carlos, 6627, 31270-901 Belo Horizonte, MG, Brazil., Vieira HGS; Garvan Institute of Medical Research, 384 Victoria Street, 2010 Sydney, NSW, Australia., Tahara EB; Universidade Federal de Minas Gerais, Instituto de Ciências Biológicas, Departamento de Bioquímica e Imunologia, Avenida Antônio Carlos, 6627, 31270-901 Belo Horizonte, MG, Brazil., Macedo AM; Universidade Federal de Minas Gerais, Instituto de Ciências Biológicas, Departamento de Bioquímica e Imunologia, Avenida Antônio Carlos, 6627, 31270-901 Belo Horizonte, MG, Brazil., Machado CR; Universidade Federal de Minas Gerais, Instituto de Ciências Biológicas, Departamento de Bioquímica e Imunologia, Avenida Antônio Carlos, 6627, 31270-901 Belo Horizonte, MG, Brazil., Franco GR; Universidade Federal de Minas Gerais, Instituto de Ciências Biológicas, Departamento de Bioquímica e Imunologia, Avenida Antônio Carlos, 6627, 31270-901 Belo Horizonte, MG, Brazil. |
| Abstrakt: |
Benznidazole (BZ) is the trypanocidal compound of choice for Chagas disease, a neglected tropical disease in the Americas. However, this drug often fails to cure the infection. The regulation of gene expression in Trypanosoma cruzi, the causative agent of Chagas disease, is based on post-transcriptional mechanisms. When environmental changes cause translational arrest, RNA-binding proteins, and their target mRNAs assemble into cytoplasmic bodies, known as RNA granules, which act as RNA sorting centers. We have characterized the T. cruzi RNA-binding protein DRBD3, which has two RRMs domains, and a C-terminal low-complexity sequence rich in proline and glutamines. Using a tagged form of TcDRBD3 (rTcDRBD3), we showed that this protein resides in the cytoplasm, but localizes into perinuclear cytoplasmic foci after BZ exposure. RNA staining after BZ also showed that this molecule accumulates into perinuclear cytoplasmic foci. Moreover, BZ and puromycin treatment enhanced the colocalization of rTcDRBD3 and RNA, suggesting that TcDRBD3 granules repertoire harbors RNAs released from polysomes. Under starvation, rTcDRBD3 granules localized throughout the cytoplasm and also increased in number in the presence of puromycin. Our results suggest that TcDRBD3 accumulates into perinuclear granules that harbor RNA and also that its localization varies according to the type of stress. |
