Studies about the function of L. major TERT component in telomere maintenance and cell proliferation

• Grant number: 20/00316-1
• Support Opportunities: Scholarships in Brazil - Doctorate (Direct)
• Start date: March 01, 2020
• End date: January 31, 2024
• Field of knowledge: Biological Sciences - Genetics - Molecular Genetics and Genetics of Microorganisms
• Principal Investigator: Maria Isabel Nogueira Cano
• Grantee: Mark Ewusi Shiburah
• Host Institution: Instituto de Biociências (IBB). Universidade Estadual Paulista (UNESP). Campus de Botucatu. Botucatu , SP, Brazil
• Associated research grant: 18/04375-2 - Studies about the biogenesis and composition of the Leishmania spp. ribonucleoprotein complex and its regulation, AP.TEM

Abstract

Leishmaniases are severe infectious diseases of great importance in public health due to high mortality, morbidity, and incidence, wide geographical distribution, a great variety of parasite species that cause the disease and lack of efficient treatment and adequate control. Therefore, the search for new antiparasitic drugs and treatment is highly necessary. In most eukaryotes, including Leishmania, telomeres, the nucleoprotein structures localized at the end of the chromosomes have been considered good targets for the development of new therapies against different diseases. Telomeres are maintained by the combined action of telomerase and telomeric proteins, and their main function is to differentiate chromosome end termini from DNA double-strand break thus, protecting chromosome ends from degradation and fusion. Leishmania telomerase complex, similarly to other eukaryotes, is minimally composed by the protein TERT component and the lncRNA TER that contains the template sequence for telomere replication. Studies about Leishmania sp. telomeres have been important to understand parasite biology and the present proposal aims to elucidate the importance of parasite TERT telomerase component in telomere lengthening maintenance and cell proliferation. To reach this goal it will be used three different approaches. The first will test the in vitro action of the synthetic telomerase inhibitor BIBR1532. It was already shown that BIBR1532 effects in vitro cell proliferation of L. amazonensis promastigotes and amastigotes, but does not affect the survival of macrophages used in the infectivity tests. The second approach will be to induce parasite TERT knockout using CRISPR-CAS9, which had been shown to be efficient in Leishmania sp. And the third approach is to overexpress TERT using an episomal plasmid containing a Flag-tag. The effects of the inhibitor, the knockout and the overexpression of TERT will be tested on cell proliferation, cell cycle, telomerase activity, and telomere length. We hope that new light will be shed on the function of the Leishmania telomeric machinery to develop new methods to counter Leishmaniases. (AU)

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

ASSIS, LUIZ H. C.; ANDRADE-SILVA, DEBORA; SHIBURAH, MARK E.; DE OLIVEIRA, BEATRIZ C. D.; PAIVA, STEPHANY C.; ABUCHERY, BRYAN E.; FERRI, YETE G.; FONTES, VERONICA S.; DE OLIVEIRA, LEILANE S.; DA SILVA, MARCELO S.; et al. Cell Cycle, Telomeres, and Telomerase in Leishmania spp.: What Do We Know So Far?. CELLS, v. 10, n. 11, NOV 2021. (19/10753-2, 20/08162-3, 21/04253-7, 20/00316-1, 20/16465-6, 18/04375-2, 21/05523-8, 20/10277-3, 19/25985-6, 20/16480-5)