Dual cellular localization of the Leishmania amazonensis Rbp38 (LaRbp38) explains its affinity for telomeric and mitochondrial DNA

Autor(es)

Fernandes, Carlos A. H. ^{[1, 2]} ; Perez, Arina M. ^[2] ; Barros, Andrea C. ^[1] ; Dreyer, Thiago R. ^[1] ; da Silva, Marcelo S. ^[3] ; Morea, Edna Gicela O. ^[2] ; Fontes, Marcos R. M. ^[1] ; Cano, Maria Isabel N. ^[2]

Afiliação do(s) autor(es)

^[1] Sao Paulo State Univ UNESP, Biosci Inst, Dept Phys & Biophys, Botucatu, SP - Brazil

^[2] Sao Paulo State Univ UNESP, Biosci Inst, Dept Genet, BR-18618689 Botucatu, SP - Brazil

^[3] Butantan Inst, Ctr Toxins Immune Response & Cell Signaling CeTIC, LECC, Sao Paulo, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Biochimie; v. 162, p. 15-25, JUL 2019.
• Citações Web of Science: 0

Resumo

Rbp38 is a protein exclusively found in trypanosomatid parasites, including Leishmania amazonensis, the etiologic agent of tegumentar leishmaniasis in the Americas. The protein was first described as a Leishmania tarentolae mitochondrial RNA binding protein. Later, it was shown that the trypanosomes Rbp38 orthologues were exclusively found in the mitochondria and involved in the stabilization and replication of kinetoplast DNA (kDNA). In contrast, L. amazonensis Rbp38 (LaRbp38), co-purifies with telomerase activity and interacts not only with kDNA but also with telomeric DNA, although shares with its counterparts high sequence identity and a putative N-terminal mitochondrial targeting signal (MTS). To understand how LaRbp38 interacts both with nuclear and kDNA, we have first investigated its subcellular localization. Using hydroxy-urea synchronized L. amazonensis promastigotes we could show that LaRbp38 shuttles from mitochondria to the nucleus at late S and G2 phases. Further, we identified a non-classical nuclear localization signal (NLS) at LaRbp38 C-terminal that binds with importin alpha, a protein involved in the nuclear transport of several proteins. Also, we obtained LaRbp38 truncated forms among which, some of them also showed an affinity for both telomeric DNA and kDNA. Analysis of these truncated forms showed that LaRbp38 DNA-binding region is located between amino acid residues 95-235. Together, our findings strongly suggest that LaRbp38 is multifunctional with dual subcellular localization. (C) 2019 Elsevier B.V. and Societe Francaise de Biochimie et Biologie Moleculaire (SFBBM). All rights reserved. (AU)

• 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: 15/18641-8 - Caracterização molecular de RNAs teloméricos não codificadores em Leishmania major
• Beneficiário: Maria Isabel Nogueira Cano
• Modalidade de apoio: Auxílio à Pesquisa - Regular