Selected Grantee Publications
Epigenetic MLH1 Silencing Concurs With Mismatch Repair Deficiency in Sporadic, Naturally Occurring Colorectal Cancer in Rhesus Macaques
Deycmar et al., Journal of Translational Medicine. 2024.
https://pubmed.ncbi.nlm.nih.gov/38504345
Rhesus macaques serve as a useful model for colorectal cancer (CRC) in humans, but more data are needed to understand the molecular pathogenesis of these cancers. Using male and female rhesus macaques, researchers investigated mismatch repair status, microsatellite instability, genetic mutations, transcriptional differences, and epigenetic alterations associated with CRC. Their data indicate that epigenetic silencing suppresses MLH1 transcription, induces the loss of MLH1 protein, abrogates mismatch repair, and drives genomic instability in naturally occurring CRC in rhesus macaques. This work provides a uniquely informative model for human CRC. Supported by ORIP (P51OD011092, R24OD010947, R24OD021324, P40OD012217, U42OD010426, T35OD010946, T32OD010957), NCATS, and NCI.
Injury-Induced Cooperation of InhibinβA and JunB is Essential for Cell Proliferation in Xenopus Tadpole Tail Regeneration
Nakamura et al., Scientific Reports. 2024.
https://pubmed.ncbi.nlm.nih.gov/38355764/
Certain animal species (e.g., amphibians) that can regenerate lost tissues and limbs after injury offer potential for applications in regenerative medicine. Cell proliferation is essential for the reconstruction of injured tissue, but the molecular mechanisms that regulate the transition from wound healing to regenerative cell proliferation remain unclear. Using Xenopus tropicalis, investigators examined the effects of injury on the expression of inhibin subunit beta A (inhba) and junB proto-oncogene (junb). Their findings shed light on the mechanisms underlying injury-induced cell proliferation in regenerative animals. Supported by ORIP (P40OD010997, R24OD030008).
Identification of Constrained Sequence Elements Across 239 Primate Genomes
Kuderna et al., Nature. 2024.
https://pubmed.ncbi.nlm.nih.gov/38030727/
Functional genomic elements that have acquired selective constraints specific to the primate order are prime candidates for understanding evolutionary changes in humans, but the selective constraints specific to the phylogenetic branch from which the human species ultimately emerged remain largely unidentified. Researchers constructed a genome-wide multiple sequence alignment of 239 primate species to better characterize constraint at noncoding regulatory sequences in the human genome. Their work reveals noncoding regulatory elements that are under selective constraint in primates but not in other placental mammals and are enriched for variants that affect human gene expression and complex traits in diseases. These findings highlight the important role of recent evolution in regulatory sequence elements differentiating primates, including humans, from other placental mammals. Supported by ORIP (P40OD024628), NHGRI, NIA, and NICHD.
GenomeMUSter Mouse Genetic Variation Service Enables Multitrait, Multipopulation Data Integration and Analysis
Ball et al., Genome Research. 2024.
https://genome.cshlp.org/content/34/1/145.long
Advances in genetics, including transcriptome-wide and phenome-wide association analysis methods, create compelling new opportunities for using fully reproducible and widely studied inbred mouse strains to characterize the polygenetic basis for individual differences in disease-related traits. Investigators developed an imputation approach and implemented data service to provide a broad and more comprehensive mouse variant resource. They evaluated the strain-specific imputation accuracy on a “held-out” test set that was not used in the imputation process. The authors present its application to multipopulation and multispecies analyses of complex trait variation in type 2 diabetes and substance use disorders and compare these results to human genetics studies. Supported by ORIP (U42OD010921, P40OD011102, R24OD035408), NCI, NIAAA, NIDA, and NIDCD.
Preclinical Safety and Biodistribution of CRISPR Targeting SIV in Non-Human Primates
Burdo et al., Gene Therapy. 2024.
https://pmc.ncbi.nlm.nih.gov/articles/PMC11090835/
Nonhuman primates have served as a valuable resource for evaluating novel eradication and cure strategies for HIV infection. Using a male rhesus macaque model, researchers demonstrated the safety and utility of CRISPR gene-editing technology for targeting integrated simian immunodeficiency virus (SIV). Their work suggests that a single intravenous inoculation for HIV gene editing can be utilized to reach viral reservoirs throughout the body. Additionally, no off-target effects or abnormal pathology were observed. Together, these findings support the continued development of HIV eradicative cure strategies using CRISPR technology in humans. Supported by ORIP (P40OD012217, U42OD021458).
Establishment of a Practical Sperm Cryopreservation Pathway for the Axolotl (Ambystoma mexicanum): A Community-Level Approach to Germplasm Repository Development
Coxe et al., Animals (Basel). 2024.
https://pubmed.ncbi.nlm.nih.gov/38254376/
The axolotl (Ambystoma mexicanum) is an important biomedical research model for organ regeneration, but housing and maintaining live animals is expensive and risky as new transgenic lines are developed. The authors report an initial practical pathway for sperm cryopreservation to support germplasm repository development. They assembled a pathway through the investigation of axolotl sperm collection by stripping, refrigerated storage in various osmotic pressures, cryopreservation in various cryoprotectants, and in vitro fertilization using thawed sperm. This work is the first report of successful production of axolotl offspring with cryopreserved sperm and provides a general framework for pathway development to establish Ambystoma germplasm repositories for future research and applications. Supported by ORIP (R24OD010441, R24OD028443, P40OD019794).
Very-Long-Chain Fatty Acids Induce Glial-Derived Sphingosine-1-Phosphate Synthesis, Secretion, and Neuroinflammation
Chung et al., Cell Metabolism. 2023.
https://pubmed.ncbi.nlm.nih.gov/37084732/
Very-long-chain fatty acids (VLCFAs) are the most abundant fatty acids in myelin. During age‑associated degeneration of myelin, glia are exposed to increased levels of VLCFAs. Investigators previously described a novel phenotype in patients that harbors a novel variant in the peroxisomal enzyme ACOX1. Here, they report that that glial loss of ACOX1 leads to an increase of VLCFAs, which results in a concomitant increase in sphingosine-1-phosphate (S1P). They found that suppressing S1P function attenuates the pathological phenotypes caused by excess VLCFAs. This work suggests that lowering of VLCFAs and S1P could be applied as a treatment avenue for multiple sclerosis. Supported by ORIP (R24OD022005, R24OD031447, P40OD018537), NINDS, and NICHD
Lipid Droplets and Peroxisomes Are Co-Regulated to Drive Lifespan Extension in Response to Mono-Unsaturated Fatty Acids
Papsdorf et al., Nature Cell Biology. 2023.
https://www.nature.com/articles/s41556-023-01136-6
Investigators studied the mechanism by which mono-unsaturated fatty acids (MUFAs) extend longevity. They found that MUFAs upregulated the number of lipid droplets in fat storage tissues of Caenorhabditis elegans, and increased lipid droplets are necessary for MUFA-induced longevity and predicted remaining lifespan. Lipidomics data revealed that MUFAs modify the ratio of membrane lipids and ether lipids, which leads to decreased lipid oxidation in middle-aged individuals. MUFAs also upregulate peroxisome number. A targeted screen revealed that induction of both lipid droplets and peroxisomes is optimal for longevity. This study opens new interventive avenues to delay aging. Supported by ORIP (S10OD025004, S10OD028536, P40OD010440), NIA, NCCIH, NIDDK, and NHGRI.
Investigation of Monoclonal Antibody CSX-1004 for Fentanyl Overdose
Bremer et al., Nature Communications. 2023.
https://pubmed.ncbi.nlm.nih.gov/38052779/
The opioid crisis in the United States is primarily driven by the highly potent synthetic opioid fentanyl and has led to more than 70,000 overdose deaths annually; thus, new therapies for fentanyl overdose are urgently needed. Here, the authors present the first clinic-ready, fully human monoclonal antibody CSX-1004 with picomolar affinity for fentanyl and related analogs. In mice, CSX-1004 reverses fentanyl antinociception and the intractable respiratory depression caused by the ultrapotent opioid carfentanil. Using a highly translational nonhuman primate model for respiratory depression, they demonstrate CSX-1004-mediated protection from repeated fentanyl challenges for 3–4 weeks. These data establish the feasibility of CSX-1004 as a promising candidate medication for preventing and reversing fentanyl-induced overdose. Supported by ORIP (P40OD010938) and NIDA.
Tenth Aquatic Models of Human Disease Conference 2022 Workshop Report: Aquatics Nutrition and Reference Diet Development
Sharpton et al., Zebrafish. 2023.
https://pubmed.ncbi.nlm.nih.gov/38117219/
Standard reference diets (SRDs) for aquatic model organisms, vital for supporting scientific rigor and reproducibility, are yet to be adopted. At this workshop, the authors presented findings from a 7-month diet test study conducted across three aquatic research facilities: Zebrafish International Resource Center (University of Oregon), Kent and Sharpton laboratories (Oregon State University), and Xiphophorus Genetic Stock Center (Texas State University). They compared the effects of two commercial diets and a suggested zebrafish SRD on general fish husbandry, microbiome composition, and health in three fish species (zebrafish, Xiphophorus, and medaka), and three zebrafish wild-type strains. They reported outcomes, gathered community feedback, and addressed the aquatic research community's need for SRD development. Discussions underscored the influence of diet on aquatic research variability, emphasizing the need for SRDs to control cross-experiment and cross-laboratory reproducibility. Supported by ORIP (P40OD011021, R24OD011120, and R24OD010998) and NICHD.