Life Sci Alliance.: co-auth.: group Roignant

Life Sci Alliance. 2023 Jan 31;6(4):e202201877. doi: 10.26508/lsa.202201877. Print 2023 Apr.

The ribose methylation enzyme FTSJ1 has a conserved role in neuron morphology and learning performance

Mira Brazane 1Dilyana G Dimitrova 1Julien Pigeon 2Chiara Paolantoni 3Tao Ye 4Virginie Marchand 5Bruno Da Silva 1Elise Schaefer 6Margarita T Angelova 1Zornitza Stark 7Martin Delatycki 7Tracy Dudding-Byth 8Jozef Gecz 9Pierre-Yves Plaçais 10Laure Teysset 1Thomas Préat 10Amélie Piton 4Bassem A Hassan 2Jean-Yves Roignant 3 11Yuri Motorin 12Clément Carré 13


FTSJ1 is a conserved human 2′-O-methyltransferase (Nm-MTase) that modifies several tRNAs at position 32 and the wobble position 34 in the anticodon loop. Its loss of function has been linked to X-linked intellectual disability (XLID), and more recently to cancers. However, the molecular mechanisms underlying these pathologies are currently unclear. Here, we report a novel FTSJ1 pathogenic variant from an X-linked intellectual disability patient. Using blood cells derived from this patient and other affected individuals carrying FTSJ1 mutations, we performed an unbiased and comprehensive RiboMethSeq analysis to map the ribose methylation on all human tRNAs and identify novel targets. In addition, we performed a transcriptome analysis in these cells and found that several genes previously associated with intellectual disability and cancers were deregulated. We also found changes in the miRNA population that suggest potential cross-regulation of some miRNAs with these key mRNA targets. Finally, we show that differentiation of FTSJ1-depleted human neural progenitor cells into neurons displays long and thin spine neurites compared with control cells. These defects are also observed in Drosophila and are associated with long-term memory deficits. Altogether, our study adds insight into FTSJ1 pathologies in humans and flies by the identification of novel FTSJ1 targets and the defect in neuron morphology.