1
|
Gómez-Pascual A, Glikman DM, Ng HX, Tomkins JE, Lu L, Xu Y, Ashbrook DG, Kaczorowski C, Kempermann G, Killmar J, Mozhui K, Aebersold R, Williams EG, Williams RW, Overall RW, Jucker M, de Bakker DEM. Polyglucosan body density in the aged mouse hippocampus is controlled by a novel modifier locus on chromosome 1. bioRxiv 2023:2023.11.22.567373. [PMID: 38045339 PMCID: PMC10690248 DOI: 10.1101/2023.11.22.567373] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/05/2023]
Abstract
Aging can be associated with the accumulation of hypobranched glycogen molecules (polyglucosan bodies, PGBs), particularly in astrocytes of the hippocampus. While PGBs have a detrimental effect on cognition in diseases such as adult polyglucosan body disease and Lafora disease, the underlying mechanism and clinical relevance of age-related PGB accumulation remains unknown. Here, we have investigated the genetic basis and functional impact of age-related PGB accumulation in 32 fully sequenced BXD-type strains of mice which exhibit a 400-fold variation in PGB burden in 16-18 month old females. We mapped a major locus controlling PGB density in the hippocampus to chromosome 1 at 72-75 Mb (linkage of 4.9 -logP), which we defined as the Pgb1 locus. To identify potentially causal gene variants within Pgb1, we generated extensive hippocampal transcriptome datasets and identified two strong candidate genes for which mRNA correlates with PGB density-Smarcal1 and Usp37. In addition, both Smarcal1 and Usp37 contain non-synonymous allele variations likely to impact protein function. A phenome-wide association analysis highlighted a trans-regulatory effect of the Pgb1 locus on expression of Hp1bp3, a gene known to play a role in age-related changes in learning and memory. To investigate the potential impact of PGBs on cognition, we performed conditioned fear memory testing on strains displaying varying degrees of PGB burden, and a phenome-wide association scan of ~12,000 traits. Importantly, we did not find any evidence suggesting a negative impact of PGB burden on cognitive capacity. Taken together, we have identified a major modifier locus controlling PGB burden in the hippocampus and shed light on the genetic architecture and clinical relevance of this strikingly heterogeneous hippocampal phenotype.
Collapse
Affiliation(s)
- A Gómez-Pascual
- Department of Information and Communications Engineering, University of Murcia, Murcia, Spain
| | - D M Glikman
- University of Vienna, Vienna, Austria
- Department of Neuronal Cell Biology, Center for Brain Research, Medical University of Vienna, Vienna, Austria
| | - H X Ng
- Department of Cognitive Science University of California, San Diego, USA
| | - J E Tomkins
- Centre for Misfolding Diseases, Department of Chemistry, University of Cambridge, Cambridge, UK
- Aligning Science Across Parkinson's (ASAP) Collaborative Research Network, Chevy Chase, MD, 20815
| | - L Lu
- Department of Genetics, Genomics and Informatics, University of Tennessee Health Center, Memphis, TN, USA
| | - Y Xu
- Department of Cellular Neurology, Hertie-Institute for Clinical Brain Research, University of Tübingen, Tübingen, Germany
- German Center for Neurodegenerative Diseases (DZNE), Tübingen, Germany
| | - D G Ashbrook
- Department of Genetics, Genomics and Informatics, University of Tennessee Health Center, Memphis, TN, USA
| | | | - G Kempermann
- German Center for Neurodegenerative Diseases (DZNE), Dresden, Germany
| | - J Killmar
- Department of Genetics, Genomics and Informatics, University of Tennessee Health Center, Memphis, TN, USA
| | - K Mozhui
- Department of Genetics, Genomics and Informatics, University of Tennessee Health Center, Memphis, TN, USA
- Department of Preventive Medicine, College of Medicine, University of Tennessee Health Center, Memphis, TN, USA
| | - R Aebersold
- Department of Biology, Institute of Molecular Systems Biology, ETH Zurich. Zurich, Switzerland
| | - E G Williams
- Luxembourg Centre for Systems Biomedicine, University of Luxembourg, Belval, Luxembourg
| | - R W Williams
- Department of Genetics, Genomics and Informatics, University of Tennessee Health Center, Memphis, TN, USA
| | - R W Overall
- Humboldt University of Berlin, Berlin, Germany
| | - M Jucker
- Department of Cellular Neurology, Hertie-Institute for Clinical Brain Research, University of Tübingen, Tübingen, Germany
- German Center for Neurodegenerative Diseases (DZNE), Tübingen, Germany
| | - D E M de Bakker
- Leibniz Institute on Aging - Fritz Lipmann Institute (FLI), Jena, Germany
| |
Collapse
|