Selected Grantee Publications
Two Neuronal Peptides Encoded from a Single Transcript Regulate Mitochondrial Complex III in Drosophila
Bosch et al., eLife. 2022.
https://www.doi.org/10.7554/eLife.82709
Transcripts with small open-reading frames (smORFs) are underrepresented in genome annotations. Functions of peptides encoded by smORFs are poorly understood. The investigators systematically characterized human-conserved smORF genes in Drosophila and found two peptides, Sloth1 and Sloth2, that are highly expressed in neurons. They showed that Sloth1 and Sloth2 are paralogs with high sequence similarity but are not functionally redundant. Loss of either peptide resulted in lethality, impaired mitochondrial function, and neurodegeneration. This work suggests the value of phenotypic analysis of smORFs using Drosophila as a model. Supported by ORIP (R24OD019847), NHGRI, and NIGMS.
De Novo Variants in EMC1 Lead to Neurodevelopmental Delay and Cerebellar Degeneration and Affect Glial Function in Drosophila
Chung et al., Human Molecular Genetics. 2022.
https://www.doi.org/10.1093/hmg/ddac053
Variants in EMC1, which encodes a subunit of the endoplasmic reticulum (ER)–membrane protein complex (EMC), are associated with developmental delay in children. Functional consequences of these variants are poorly understood. The investigators identified de novo variants in EMC1 in three children affected by global developmental delay, hypotonia, seizures, visual impairment, and cerebellar atrophy. They demonstrated in Drosophila that these variants are loss-of-function alleles and lead to lethality when expressed in glia but not in neurons. This work suggests the causality of EMC variants in disease. Supported by ORIP (R24OD022005, R24OD031447), NINDS, and NICHD.
Promoting Validation and Cross-Phylogenetic Integration in Model Organism Research
Cheng et al., Disease Models & Mechanisms. 2022.
https://www.doi.org/10.1242/dmm.049600
Model organisms are essential for biomedical research and therapeutic development, but translation of such research to the clinic is low. The authors summarized discussions from an NIH virtual workshop series, titled “Validation of Animal Models and Tools for Biomedical Research,” held from 2020 to 2021. They described challenges and opportunities for developing and integrating tools and resources and provided suggestions for improving the rigor, validation, reproducibility, and translatability of model organism research. Supported by ORIP (R01OD011116, R24OD031447, R03OD030597, R24OD018559, R24OD017870, R24OD026591, R24OD022005, U42OD026645, U42OD012210, U54OD030165, UM1OD023221, P51OD011107), NIAMS, NIDDK, NIGMS, NHGRI, and NINDS.
Rbbp4 Loss Disrupts Neural Progenitor Cell Cycle Regulation Independent of Rb and Leads to Tp53 Acetylation and Apoptosis
Schultz-Rogers et al., Developmental Dynamics. 2022.
https://www.doi.org/10.1002/dvdy.467
Retinoblastoma binding protein 4 (Rbbp4) is a component of transcription regulatory complexes that control cell cycle gene expression by cooperating with the Rb tumor suppressor to block cell cycle entry. The authors used genetic analysis to examine the interactions of Rbbp4, Rb, and Tp53 in zebrafish neural progenitor cell cycle regulation and survival. Rbbp4 is upregulated across the spectrum of human embryonal and glial brain cancers, and it is essential for zebrafish neurogenesis. Rbbp4 loss leads to apoptosis and γ-H2AX in the developing brain that is suppressed by tp53 knockdown or maternal zygotic deletion. Mutant retinal neural precursors accumulate in M phase and fail to initiate G0 gene expression. Rbbp4; Rb1 double mutants show an additive effect on the number of M phase cells. The study demonstrates that Rbbp4 is necessary for neural progenitor cell cycle progression and initiation of G0, independent of Rb, and suggests that Rbbp4 is required for cell cycle exit and contributes to neural progenitor survival. Supported by ORIP (R24OD020166) and NIGMS.
A Multidimensional Metabolomics Workflow to Image Biodistribution and Evaluate Pharmacodynamics in Adult Zebrafish
Jackstadt et al., Disease Models & Mechanisms. 2022.
https://www.doi.org/10.1242/dmm.049550
The evaluation of tissue distribution and pharmacodynamic properties of a drug is essential but often expensive in clinical research. The investigators developed a multidimensional metabolomics platform to evaluate drug activity that integrates mass spectrometry–based imaging, absolute drug quantitation, in vivo isotope tracing, and global metabolome analysis in zebrafish. They validated this platform by evaluating whole-body distribution of the anti-rheumatic agent hydroxychloroquine sulfate and its impact on the systemic metabolism of adult zebrafish. This work suggests that the multidimensional metabolomics platform is a cost-effective method for evaluating on- and off-target effects of drugs. Supported by ORIP (R24OD024624) and NIEHS.
Allogeneic MHC‑Matched T‑Cell Receptor Α/Β‑Depleted Bone Marrow Transplants in SHIV‑Infected, ART‑Suppressed Mauritian Cynomolgus Macaques
Weinfurter et al., Scientific Reports. 2022.
https://www.doi.org/10.1038/s41598-022-16306-z
Allogeneic hematopoietic stem cell transplants are effective in reducing HIV reservoirs following antiretroviral therapy (ART). A better understanding of this mechanism could enable the development of safer and more efficacious HIV treatment regimens. In this study, the researchers used a Mauritian cynomolgus macaque model to study the effects of allogeneic major histocompatibility complex–matched α/β T cell–depleted bone marrow cell transplantation following infection with simian–human immunodeficiency virus (SHIV). The macaques began ART 6 to 16 weeks post-infection. In three of the four macaques, SHIV DNA was undetectable in blood but persisted in other tissues. These results suggest that extended ART likely is needed to eradicate the HIV reservoir following transplantation. In future studies, full donor engraftment should be balanced with suppression of graft-versus-host disease. Supported by ORIP (P51OD011106, R24OD021322), and NCI.
Generation of SIV-Resistant T Cells and Macrophages from Nonhuman Primate Induced Pluripotent Stem Cells with Edited CCR5 Locus
D’Souza et al., Stem Cell Reports. 2022.
https://www.doi.org/10.1016/j.stemcr.2022.03.003
Genetically modified T cells have shown promise as a potential therapy for HIV. A renewable source of T cells from induced pluripotent stem cells (iPSCs) could help to further research progress in this area. The researchers used Mauritian cynomolgus macaques to generate simian immunodeficiency virus (SIV)–resistant T cells and macrophages from iPSCs. These engineered cells demonstrated impaired capacity for differentiation into CD4+CD8+ T cells. T cells and macrophages from the edited iPSCs did not support SIV replication. These findings could be applied to the development of new HIV therapies. Supported by ORIP (R24OD021322, P51OD011106) and NHLBI.
Adverse Biobehavioral Effects in Infants Resulting from Pregnant Rhesus Macaques’ Exposure to Wildfire Smoke
Capitanio et al., Nature Communications. 2022.
https://www.doi.org/10.1038/s41467-022-29436-9
Exposure to wildfire smoke (WFS) is a growing health concern as wildfires increase in number and size due to climate change. Researchers found that developing rhesus monkeys exposed to WFS from the Camp Fire in California (November 2018) during the first third of gestation exhibited greater inflammation, blunted cortisol, more passive behavior, and memory impairment compared to animals conceived after smoke had dissipated. Analysis of a historical control cohort did not support the alternative hypothesis that conception timing alone explained the results. These findings suggest that WFS may have a teratogenic effect on neural development in the primate fetus. Supported by ORIP (P51OD011107, R24OD010962) and NIEHS.
Antibody-Peptide Epitope Conjugates for Personalized Cancer Therapy
Zhang et al., Cancer Research. 2022.
https://pubmed.ncbi.nlm.nih.gov/34965933/
Antibody-peptide epitope conjugates (APEC) are a new class of modified antibody-drug conjugates that redirect T cell viral immunity against tumor cells. Investigators developed an experimental pipeline to create patient-specific APECs and identified new preclinical therapies for ovarian carcinoma. Based on functional assessment of viral peptide antigen responses to common viruses like cytomegalovirus in ovarian cancer patients, a library of 192 APECs with distinct protease cleavage sequences was created using the anti-epithelial cell adhesion molecule (EpCAM) antibody. The streamlined and systemic approach includes assessing APEC function in vivo using a new zebrafish xenograft platform that facilitates high-resolution single-cell imaging to assess therapy responses and then validating top candidates using traditional mouse xenograft studies and primary patient samples. This study develops a high-throughput preclinical platform to identify patient-specific antibody-peptide epitope conjugates that target cancer cells and demonstrates the potential of this immunotherapy approach for treating ovarian carcinoma. Supported by ORIP (R24OD016761).