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Biology subjects

Baldock, P. A.

Publications and source records attributed to Baldock, P. A..

3 recordsLinked to original sources

Multiscale analysis and functional validation of the cellular and genetic determinants of skeletal disease

Musculoskeletal diseases are a major health burden. Development of bone-active therapies has been hindered by limited understanding of the cells and genes that regulate the skeleton. We exploited the value of cross-species analysis and developed single-cell methodologies in skeletal tissues to define the critical endosteal compartment that regulates bone turnover. Thirty-four distinct cell types were identified, and disease-relevant cells prioritised by enrichment for rare skeletal disorder genes and bone mineral density-associated genes in an extended UK Biobank GWAS. Functional validation was undertaken in over one thousand genetically modified mouse models. Endothelial and vascular smooth muscle cells were identified as novel skeletal disease-relevant cells alongside osteoblast, chondrocyte and osteoclast cell lineages. Hundreds of cell-specific genes with unappreciated roles in skeletal pathophysiology were identified. This comprehensive cellular and molecular framework underpins skeletal physiology and disease, and will help prioritise new therapeutic targets to accelerate development of novel therapies to treat musculoskeletal disease.

genetics↗

Osteocyte Transcriptome Mapping Identifies a Molecular Landscape Controlling Skeletal Homeostasis and Susceptibility to Skeletal Disease

Osteocytes are master regulators of the skeleton. We mapped the transcriptome of osteocytes from different skeletal sites, across age and sexes in mice to reveal genes and molecular programs that control this complex cellular-network. We define an osteocyte transcriptome signature of 1239 genes that distinguishes osteocytes from other cells. 77% have no previously known role in the skeleton and are enriched for genes regulating neuronal network formation, suggesting this program is important in osteocyte communication. We evaluated 19 skeletal parameters in 733 knockout mouse lines and reveal 26 osteocyte transcriptome signature genes that control bone structure and function. We showed osteocyte transcriptome signature genes are enriched for human orthologs that cause monogenic skeletal disorders (P=2.4x10-22) and are associated with the polygenic diseases osteoporosis (P=1.8x10-13) and osteoarthritis (P=1.6x10-7). Thus, we reveal the molecular landscape that regulates osteocyte network formation and function and establish the importance of osteocytes in human skeletal disease.

systems biology↗

Direct evidence for transport of RNA from the mouse brain to the germline and offspring

BackgroundThe traditional concept that heritability occurs exclusively from the transfer of germline-restricted genetics is being challenged by the increasing accumulation of evidence confirming the existence of experience-dependent transgenerational inheritance. However, questions remain unanswered as to how heritable information can be passed from somatic cells. Previous studies have implicated the critical involvement of RNA in heritable transgenerational effects and the high degree of mobility and genomic impact of RNAs in all organisms is an attractive model for the efficient transfer of genetic information.\n\nResultsWe hypothesized that RNA may be transported from a somatic tissue, in this case the brain, of an adult male mouse to the germline, and subsequently to offspring. To investigate this, we injected one hemisphere of the male mouse striatum with an AAV1/9 virus expressing human pre-MIR941 (MIR941). After 2, 8 and 16 weeks following injection, we used an LNA-based qPCR system to detect the presence of virus and human MIR941 in brain, peripheral tissues and offspring, from injected male mice mated with uninjected females. Virus was never detected outside of the brain. Verification of single bands of the correct size for MIR941 was performed using Sanger sequencing while quantitation demonstrated that a small percentage ([~] 1-8%) of MIR941 is transported to the germline and to offspring in about a third of the cases.\n\nConclusionsWe show that somatic RNA can be transported to the germline and passed on to offspring, thereby providing additional evidence of a role for RNA in somatic cell-derived transgenerational effects.

evolutionary biology↗