ALKB-8, a 2-Oxoglutarate-Dependent Dioxygenase and S-Adenosine Methionine-Dependent Methyltransferase Modulates Metabolic Events Linked to Lysosome-Related Organelles and Aging in <i>C. elegans</i>

Kollárová, J.; Kostrouchová, Marta; Benda, A.; Kostrouchová, Markéta

doi:10.14712/fb2018064020046

Folia Biologica > Archive > 2018, Vol. 64 > Issue 2 > ALKB-8, a 2-Oxoglutarate-Dependent…

Fol. Biol. 2018, 64, 46-58

https://doi.org/10.14712/fb2018064020046

ALKB-8, a 2-Oxoglutarate-Dependent Dioxygenase and S-Adenosine Methionine-Dependent Methyltransferase Modulates Metabolic Events Linked to Lysosome-Related Organelles and Aging in C. elegans

J. Kollárová¹, Marta Kostrouchová^1,2, A. Benda³, Markéta Kostrouchová¹

¹BIOCEV, First Faculty of Medicine, Charles University, Vestec, Czech Republic
²Department of Pathology, Third Faculty of Medicine, Charles University, Prague, Czech Republic
³Imaging Methods Core Facility, BIOCEV, Faculty of Science, Charles University, Prague, Czech Republic

Received May 2018
Accepted May 2018

ALKB-8 is a 2-oxoglutarate-dependent dioxygenase homologous to bacterial AlkB, which oxidatively demethylates DNA substrates. The mammalian AlkB family contains AlkB homologues denominated ALKBH1 to 8 and FTO. The C. elegans genome includes five AlkB-related genes, homologues of ALKBH1, 4, 6, 7, and 8, but lacks homologues of ALKBH2, 3, and 5 and FTO. ALKBH8 orthologues differ from other AlkB family members by possessing an additional methyltransferase module and an RNA binding N-terminal module. The ALKBH8 methyltransferase domain generates the wobble nucleoside 5-methoxycarbonylmethyluridine from its precursor 5-carboxymethyluridine and its (R)- and (S)-5-methoxycarbonylhydroxymethyluridine hydroxylated forms in tRNA^Arg_UCG and tRNA^Gly_UCC. The ALKBH8/ALKB-8 methyltransferase domain is highly similar to yeast TRM9, which selectively modulates translation of mRNAs enriched with AGA and GAA codons under both normal and stress conditions. In this report, we studied the role of alkb-8 in C. elegans. We show that downregulation of alkb-8 increases detection of lysosome-related organelles visualized by Nile red in vivo. Reversely, forced expression of alkb-8 strongly decreases the detection of this compartment. In addition, overexpression of alkb-8 applied in a pulse during the L1 larval stage increases the C. elegans lifespan.

Keywords

lifespan, lysosome-related organelle, methyltransferase, multifunctional enzyme, Nile red, oxidoreductase, RNA-binding, transferase.

Funding

The wild-type N2 C. elegans were provided by the C. elegans Stock Center (CGC), which is funded by NIH Office of Research Infrastructure Programs (P40 OD010440). This work was supported by the European Regional Development Fund “BIOCEV – Biotechnology and Biomedicine Centre of the Academy of Sciences and Charles University in Vestec” (CZ.1.05/ 1.1.00/02.0109) and the LQ1604 National Sustainability Programme II (Project BIOCEV-FAR) and project BIOCEV (CZ.1.05/1.1.00/ 02.0109) from the Ministry of Education, Youth and Sports of the Czech Republic; PROGRES Q26/LF1 and PROGRES Q28 “Oncology” from Charles University; grant SVV 260377 from Charles University. The imaging was done at the Imaging Methods Core Facility at BIOCEV, Faculty of Science, Charles University, supported by the Czech-BioImaging large RI project (LM2015062 funded by MEYS CR). AB acknowledges the support by MEYS CR (CZ.02.1.01/ 0.0/0.0/16 013/0001775 Czech-Bioimaging).