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Neuronal activity induces glucosylceramide that is secreted via exosomes for lysosomal degradation in glia.

ABSTRACT: Recessive variants in GBA1 cause Gaucher disease, a prevalent form of lysosome storage disease. GBA1 encodes a lysosomal enzyme that hydrolyzes glucosylceramide (GlcCer) into glucose and ceramide. Its loss causes lysosomal dysfunction and increased levels of GlcCer. We generated a null allele of the Drosophila ortholog Gba1b by inserting the Gal4 using CRISPR-Cas9. Here, we show that Gba1b is expressed in glia but not in neurons. Glial-specific knockdown recapitulates the defects found in Gba1b mutants, and these can be rescued by glial expression of human GBA1. We show that GlcCer is synthesized upon neuronal activity, and it is transported from neurons to glia through exosomes. Furthermore, we found that glial TGF-β/BMP induces the transfer of GlcCer from neurons to glia and that the White protein, an ABCG transporter, promotes GlcCer trafficking to glial lysosomes for degradation.

SUBMITTER: Wang L

PROVIDER: S-EPMC9278864 | biostudies-literature | 2022 Jul

REPOSITORIES: biostudies-literature

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Neuronal activity induces glucosylceramide that is secreted via exosomes for lysosomal degradation in glia.

Wang Liping L Lin Guang G Zuo Zhongyuan Z Li Yarong Y Byeon Seul Kee SK Pandey Akhilesh A Bellen Hugo J HJ

Science advances 20220713 28

Recessive variants in GBA1 cause Gaucher disease, a prevalent form of lysosome storage disease. GBA1 encodes a lysosomal enzyme that hydrolyzes glucosylceramide (GlcCer) into glucose and ceramide. Its loss causes lysosomal dysfunction and increased levels of GlcCer. We generated a null allele of the Drosophila ortholog Gba1b by inserting the Gal4 using CRISPR-Cas9. Here, we show that Gba1b is expressed in glia but not in neurons. Glial-specific knockdown ...[more]

PMID: 35857503

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