Biology subjects

Price, J. L.

Publications and source records attributed to Price, J. L..

4 recordsLinked to original sources

bioRxiv2026

Mesenchymal stem cell-extracellular vesicles deliver microRNAs that prevent nerve growth factor-induced sensory neuron sensitization

Osteoarthritis (OA) affects 600 million individuals globally, pain being a hallmark symptom. Emerging clinical evidence supports the use of mesenchymal stem cells (MSCs) and their extracellular vesicles (MSC-EVs) for pain relief in knee OA. In mice, MSC-EVs ameliorate OA-induced pain and normalize knee-innervating neuron excitability. Moreover, it has been shown that overnight incubation of sensory neurons with MSC-EVs prevents the OA-associated mediator nerve growth factor (NGF) sensitizing sensory neurons. Here, we found that protease-mediated MSC-EV shaving inhibited MSC-EV internalization into sensory neurons and the ability of MSC-EVs to prevent NGF-induced sensitization. In addition, acute, 10-minute, exposure of sensory neurons to MSC-EVs was also insufficient to counteract NGF. We hypothesized that MSC-EVs trigger transcriptional changes and found that inhibiting transcription prevented NGF-induced sensitization. MicroRNAs (miRNAs) can be delivered to cells by MSC-EVs, and certain miRNAs regulate transcription and pain; small RNA-sequencing of our MSC-EVs identified three candidate miRNAs, miR-21-5p, miR-148a-3p and miR-451a. Using gold nanoparticle delivery, each miRNA was able to prevent NGF sensitization of sensory neurons, a combination of all three showing the most pronounced effect. These findings demonstrate that MSC-EVs prevent NGF-induced sensory neuron sensitization via cellular uptake and transcriptional regulation that is mediated by miRNAs.

neuroscience↗

bioRxiv2023

The histone chaperone activity of SPT2 controls chromatin structure and function in Metazoa

Histone chaperones control nucleosome density and chromatin structure. In yeast, the H3-H4 chaperone Spt2 controls histone deposition at active genes but its roles in metazoan chromatin structure and organismal physiology are not known. Here we identify the Caenorhabditis elegans orthologue of SPT2 (CeSPT-2) and show that its ability to bind histones H3-H4 is important for germline development and transgenerational epigenetic gene silencing, and that spt-2 mutants display signatures of a global stress response. Genome-wide profiling showed that CeSPT-2 binds to a range of highly expressed genes, and we find that spt-2 mutants have increased chromatin accessibility at these loci. We also show that human SPT2 controls the incorporation of new H3.3 into chromatin. Our work reveals roles for SPT2 in controlling chromatin structure and function in Metazoa.

molecular biology↗

bioRxiv2022

A probabilistic view of protein stability, conformational specificity, and design

Several recently introduced approaches use neural networks as probabilistic models for protein sequence design. These models use various objective functions and optimization schemes. The choice of objective function and optimization scheme comes with trade-offs that are not always well explained. We introduce probabilistic definitions of protein stability and conformational specificity and show how these chemical properties relate to the p(structure| seq) objective used in recent protein design algorithms. This links probabilistic objective functions to experimentally testable outcomes. We present a new sequence decoding algorithm, termed "BayesDesign", that uses Bayes Rule to maximize the p(structure| seq) objective. We evaluate BayesDesign in the context of two protein model systems, the NanoLuc enzyme and the WW structural motif.

bioinformatics↗

bioRxiv2021

Visualising formation of the ribosomal active site in mitochondria

Ribosome assembly is an essential and complex process that is regulated at each step by specific biogenesis factors. Using cryo-electron microscopy, we identify and order major steps in the formation of the highly conserved peptidyl transferase centre (PTC) and tRNA binding sites in the large subunit of the human mitochondrial ribosome (mitoribosome). The conserved GTPase GTPBP7 regulates the folding and incorporation of core 16S ribosomal RNA (rRNA) helices and the ribosomal protein bL36m, and ensures that the PTC base U3039 has been 2'-O-methylated. Additionally, GTPBP7 binds the RNA methyltransferase NSUN4 and MTERF4, which facilitate earlier steps by sequestering H68-71 of the 16S rRNA and allowing biogenesis factors to access the maturing PTC. Consistent with the central role of NSUN4*MTERF4 and GTPBP7 during mitoribosome biogenesis, in vivo mutagenesis designed to disrupt binding of their Caenorhabditis elegans orthologs to the large subunit potently activates mitochondrial stress responses and results in severely reduced viability, developmental delays and sterility. Next-generation RNA sequencing reveals widespread gene expression changes in these mutant animals that are indicative of mitochondrial stress response activation. We also answer the long-standing question of why NSUN4 but not its enzymatic activity, is indispensable for mitochondrial protein synthesis in metazoans.

biochemistry↗