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bioRxiv · 10.1101/2020.03.25.007542

Brainstem development requires galactosylceramidase and is critical for the pathogenesis of Krabbe Disease

Abstract

Krabbe disease (KD) is caused by a deficiency of galactosylceramidase (GALC), which induces demyelination and neurodegeneration due to accumulation of cytotoxic psychosine. Hematopoietic stem cell transplantation (HSCT) improves clinical outcomes in KD patients only if delivered pre-symptomatically. We hypothesized that the restricted temporal efficacy of HSCT reflects a requirement for GALC in early brain development. Using a novel Galc floxed allele, we induced ubiquitous GALC ablation (Galc-iKO) at various postnatal timepoints and identified a critical period of vulnerability to GALC ablation between P4-6. Early Galc-iKO induction caused a worse KD phenotype, higher psychosine levels, and a significantly shorter life-span. Intriguingly, GALC expression peaks during this critical developmental period. Further analysis revealed a novel cell autonomous role for GALC in the development and maturation of immature T-box-brain-1 positive brainstem neurons. These data identify a perinatal developmental period, in which neuronal GALC expression influences brainstem development that is critical for KD pathogenesis.

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BibTeXRIS

Weinstock, N. I., Kreher, C., Favret, J., Bongarzone, E., Wrabetz, L., Feltri, M. L., Shin, D.. 2020-03-25. Brainstem development requires galactosylceramidase and is critical for the pathogenesis of Krabbe Disease. https://doi.org/10.1101/2020.03.25.007542

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