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bioRxiv · 10.64898/2026.09.13.751333

Ile35 residue of SOD1 plays a key role in aggregate formation and eye degeneration in a Drosophila model of ALS

Abstract

{middle dot}The pathophysiology of ALS caused by mutant SOD1 remains unclear. {middle dot}We previously demonstrated, using the BioID2-EGFP sandwich expression system in cultured cells, that the Ile35 residue of ALS-linked mutant SOD1 promotes its aggregate formation. {middle dot}However, the precise role of the SOD1 Ile35 residue in aggregate formation and neurodegeneration in vivo remained unclear. {middle dot}Drosophila expressing BioID2-G93A-EGFP demonstrated aggregate formation and eye degeneration with reduced eye size, whereas those expressing BioID2-G93A/I35S-EGFP showed less of these phenotypes. {middle dot}These findings highlight the crucial role of the Ile35 residue of ALS-linked SOD1 in aggregate formation and neurodegeneration in vivo.

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Yano, K., Fujino, Y., Nagai, Y., Fujiwara, N.. 2026-09-19. Ile35 residue of SOD1 plays a key role in aggregate formation and eye degeneration in a Drosophila model of ALS. https://doi.org/10.64898/2026.09.13.751333

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