Identification of soma-germline interactions that may influence lifespan in Caenorhabditis elegans

• Grant number: 16/02207-0
• Support Opportunities: Scholarships abroad - Research Internship - Master's degree
• Start date: April 28, 2016
• End date: June 27, 2016
• Field of knowledge: Biological Sciences - Biochemistry - Molecular Biology
• Principal Investigator: Marcelo Alves da Silva Mori
• Grantee: Evandro Araújo de Souza
• Supervisor: Adam Antebi
• Host Institution: Escola Paulista de Medicina (EPM). Universidade Federal de São Paulo (UNIFESP). Campus São Paulo. São Paulo , SP, Brazil
• Institution abroad: Max Planck Society, Dresden, Germany
• Associated to the scholarship: 14/10814-8 - Determination of factors that controls Dicer expression in vivo in C. elegans, BP.MS

Abstract

C. elegans is a widely used model for aging studies due to its short lifespan and conserved genes that can be easily silenced by feeding worms with bacteria that express target-specific double stranded RNA (dsRNA). Worms carrying a loss-of-function mutation in the glp-1 gene do not develop the germline and therefore are long-lived - a phenomenon directly linked to increased nuclear localization of the transcription factor DAF-16/FOXO in somatic cells. When using RNAi by feeding to identify genes that interact with this phenotype, we serendipitously found that our control vector L4440, blocked DAF-16 nuclear translocation in the intestine of glp-1 mutants. This was not observed in wild type worms after heat shock - an intervention that also leads to DAF- 16 translocation. The L4440 effect was dependent on intrinsic dsRNA production and was not driven by the vector's backbone, since removal of the multiple cloning site (MCS) or the T7 promoters abolished the DAF-16 phenotype. Activation of the RNAi pathway is not sufficient to explain the effect of the vector, since we observed nuclear DAF-16 in glp-1 mutants when we used RNAi vectors targeting endogenous genes (i.e. pos-1 or lin-1). To confirm whether the dsRNA expressed by the MCS region is inhibiting DAF-16 nuclear localization in the glp-1 mutant, we aim to directly inject this fragment into worms. Additionally, we want to test if this phenomenon occurs in another germline ablation model using laser to kill germline precursor cells. Collectively, our results suggest that the non-self dsRNA produced by the L4440 vector disrupts DAF-16 translocation in germlineless animals. The outcome of this project could be a cautionary note for the unrestricted use of the L4440 vector in RNAi experiments in C. elegans. In addition, it may bring insights into how the RNAi pathway affects longevity.

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)

GUERRA, BEATRIZ A.; BRANDAO, BRUNA B.; PINTO, SILAS S.; SALGUEIRO, WILLIAN G.; DE-SOUZA, EVANDRO A.; REIS, FELIPE C. G.; BATISTA, THIAGO M.; CAVALCANTE-SILVA, VANESSA; D'ALMEIDA, VANIA; CASTILHO, BEATRIZ A.; et al. Dietary sulfur amino acid restriction upregulates DICER to confer beneficial effects. MOLECULAR METABOLISM, v. 29, p. 124-135, NOV 2019. (15/03292-8, 17/22057-5, 10/52557-0, 16/02207-0, 17/01184-9, 15/01316-7, 15/19530-5, 12/07259-7, 17/07975-8)

DE-SOUZA, EVANDRO A.; CAMARA, HENRIQUE; SALGUEIRO, WILLIAN G.; MORO, RAISSA P.; KNITTEL, THIAGO L.; TONON, GUILHERME; PINTO, SILAS; PINCA, ANA PAULA F.; ANTEBI, ADAM; PASQUINELLI, AMY E.; et al. RNA interference may result in unexpected phenotypes in Caenorhabditis elegans. Nucleic Acids Research, v. 47, n. 8, p. 3957-3969, MAY 7 2019. (12/00195-3, 10/52557-0, 17/22057-5, 17/04377-2, 17/03423-0, 16/02207-0, 17/08829-5, 15/01316-7, 17/01339-2, 14/10814-8, 17/01184-9, 14/25068-0, 16/15958-3)