Biology subjects

Booth, C. D.

Publications and source records attributed to Booth, C. D..

5 recordsLinked to original sources

bioRxiv2026

CLN6 is a glycerophosphoglycerol epimerase in bis(monoacylglycero)phosphate biosynthesis

Lysosomal catabolism depends on bis(monoacylglycero)phosphate (BMP), a phospholipid with atypical S,S stereochemistry of unknown biosynthetic origin. CLN8 and CLN5 catalyze sequential acylation steps in BMP synthesis, and their loss of function causes Batten disease, a group of inherited neurodegenerative lysosomal storage disorders. Here we identify CLN6, a biochemically uncharacterized endoplasmic reticulum protein whose loss also causes Batten disease, as the calcium-dependent glycerophosphoglycerol epimerase that establishes BMP stereochemistry upstream of CLN8. CLN6 deficiency depletes BMP in cells, mice, and patient lysosomes, and reduces lysosomal hydrolase levels. BMP-precursor supplementation bypasses CLN6, restores BMP and increases hydrolase abundance in CLN6-deficient cells and mice. These findings place three Batten disease proteins in a single biosynthetic pathway and reveal BMP deficiency as a reversible cause of disrupted lysosomal hydrolase homeostasis.

biochemistry↗

bioRxiv2025

Stereospecific GPG acylation by CLN8 drives BMP biosynthesis and its loss leads to Batten disease

Loss-of-function mutations in the endoplasmic reticulum membrane protein CLN8 cause Batten disease, a neurodegenerative lysosomal storage disorder1. Together with the lysosomal enzyme CLN5, CLN8 mediates the biosynthesis of bis(monoacylglycero)phosphate (BMP), a phospholipid essential for lysosomal function and distinguished by its unique S,S stereochemistry2,3. However, the role of CLN8 in BMP synthesis has remained unclear. Here we establish that CLN8 is a glycerophosphoglycerol (GPG) acyltransferase that catalyses the stereospecific acylation of S,S-GPG to produce S,S-lysophosphatidylglycerol (LPG), the CLN5 substrate in BMP synthesis. Using cryo-electron microscopy, we resolve structures of the CLN8 homodimer in apo and substrate-bound states at 2.7 [A] resolution, revealing the active site architecture and a ping-pong acyl transfer mechanism. Batten disease-causing missense mutations impair CLN8 enzymatic activity in vitro and reduce BMP levels in a Cln8R24G knock- in mouse, whereas the Cln8mnd mouse frameshift mutation causes complete loss of BMP in vivo. Exogenous S,S-LPG, but not the R,S stereoisomer, restored BMP synthesis in CLN8- deficient cells and mice, and improved neurological phenotypes in cln8 mutant zebrafish. Together, these findings define the enzymatic function of CLN8, elucidate the biochemical basis of CLN8 Batten disease, and establish a proof-of-concept for treating it through stereospecific BMP precursor supplementation.

biochemistry↗

bioRxiv2025

Therapeutic antisense oligonucleotide mitigates retinal dysfunction in a pig model of CLN3 Batten disease

CLN3 Batten disease is a lethal pediatric autosomal recessive neurodegenerative disease caused by mutations in the CLN3 gene. Typically, the disease manifests as vision loss early in life and progresses to neurological dysfunction and death in young adulthood. Therapeutic development has focused on treating the central nervous system. However, such therapies may not protect against vision loss, which has a significant impact on quality of life. We have shown that a splice-switching antisense oligonucleotide (ASO) delivered to the central nervous system can reduce neurological disease burden in mouse models of CLN3 disease. Here, we report on a similar ASO approach for treating CLN3 Batten disease retinal dysfunction in a pig model of the disease, which is more representative of human vision. A single intravitreal injection of ASO induces robust exon skipping in the retina for up to 12 months. The ASO treatment resulted in higher amplitudes on electroretinograms, suggesting mitigation of retinal dysfunction at early timepoints of disease. One ASO that efficiently induces exon skipping in vivo was well-tolerated and targets a region of CLN3 that is conserved in humans, making it a promising candidate for treating the disease in humans. Our findings demonstrate the potential utility of an ASO-based approach to treat retinal dysfunction in CLN3 Batten disease and generally supports the use of ASOs for treating eye diseases. One Sentence SummarySplice-switching antisense oligonucleotides delivered by intravitreal injection are safe and show efficacy in preventing early retinal dysfunction in a pig model of CLN3 Batten disease.

molecular biology↗

bioRxiv2023

Sortilin inhibition treats multiple neurodegenerative lysosomal storage disorders.

Lysosomal storage disorders (LSDs) are a genetically and clinically diverse group of diseases characterized by lysosomal dysfunction. Batten disease is a family of severe LSDs primarily impacting the central nervous system. Here we show that AF38469, a small molecule inhibitor of sortilin, improves lysosomal and glial pathology across multiple LSD models. Live-cell imaging and comparative transcriptomics demonstrates that the transcription factor EB (TFEB), an upstream regulator of lysosomal biogenesis, is activated upon treatment with AF38469. Utilizing CLN2 and CLN3 Batten disease mouse models, we performed a short-term efficacy study and show that treatment with AF38469 prevents the accumulation of lysosomal storage material and the development of neuroinflammation, key disease associated pathologies. Tremor phenotypes, an early behavioral phenotype in the CLN2 disease model, were also completely rescued. These findings reveal sortilin inhibition as a novel and highly efficacious therapeutic modality for the treatment of multiple forms of Batten disease.

neuroscience↗

bioRxiv2020

AAV9 gene therapy restores lifespan and treats pathological and behavioral abnormalities in a mouse model of CLN8-Batten disease

CLN8 disease is a rare form of neuronal ceroid lipofuscinosis caused by biallelic mutations in the CLN8 gene, which encodes a transmembrane endoplasmic reticulum protein involved in trafficking of lysosomal enzymes. CLN8 disease patients present with myoclonus, tonic-clonic seizures, and progressive declines in cognitive and motor function, with many cases resulting in premature death early in life. There are currently no treatments that can cure the disease or substantially slow disease progression. Using a mouse model of CLN8 disease, we tested the safety and efficacy of an intracerebroventricularly (ICV)-delivered self-complementary AAV9 (scAAV9) gene therapy vector driving expression of human CLN8. A single neonatal injection was safe and well-tolerated, resulting in robust transgene expression throughout the brain and spinal cord from 4 to 24 months, reducing histopathological and behavioral hallmarks of the disease and completely restoring lifespan from 10 months in untreated animals to beyond 24 months of age in treated animals. These results demonstrate, by far, the most successful rescue reported in an animal model of CLN8 disease, and supports gene therapy as a promising therapeutic strategy for this disorder.

neuroscience↗