Selected Grantee Publications
TMEM161B Modulates Radial Glial Scaffolding in Neocortical Development
Wang et al., PNAS. 2023.
https://www.pnas.org/doi/10.1073/pnas.2209983120
Neocortical folding (i.e., gyrification) is a fundamental evolutionary mechanism allowing the expansion of cortical surface area and increased cognitive function. This study identifies TMEM161B in gyral spacing in humans, likely affecting radial glial cell polarity through effects on the actin cytoskeleton. Patients carrying TMEM161B mutations exhibit striking neocortical polymicrogyria and intellectual disability. TMEM161B knockout mice fail to develop midline hemispheric cleavage, whereas knock-in of patient mutations and patient-derived brain organoids show defects in apical cell polarity and radial glial scaffolding. The data implicating TMEM161B in murine holoprosencephaly may suggest shared mechanisms between the formation of the brain midline and cortical gyrification. Supported by ORIP (U54OD030187), NINDS, and NHGRI.
De Novo Protein Fold Design Through Sequence-Independent Fragment Assembly Simulations
Pearce et al., PNAS. 2023.
https://doi.org/10.1073/pnas.2208275120
Researchers developed an automated open-source program, FoldDesign, to create high-fidelity stable folds. Through sequence-independent replica-exchange Monte Carlo simulations and energy force field optimalization of secondary structure, FoldDesign can render novel areas of protein structure and function space that natural proteins have not reached through evolution. These completely different yet stable structures replicate natural proteins’ characteristics with closely matching buried residues and solvent-exposed areas. This work demonstrates a strong potential of creating desired protein structures with potential clinical and industrial applications. Supported by ORIP (S10OD026825), NIAID, NCI, NIEHS, and NIGMS.
Gigapixel Imaging With a Novel Multi-Camera Array Microscope
Thomson et al., eLife. 2022.
https://www.doi.org/10.7554/eLife.74988
The dynamics of living organisms are organized across many spatial scales. The investigators created assembled a scalable multi-camera array microscope (MCAM) that enables comprehensive high-resolution, large field-of-view recording from multiple spatial scales simultaneously, ranging from structures that approach the cellular scale to large-group behavioral dynamics. By collecting data from up to 96 cameras, they computationally generated gigapixel-scale images and movies with a field of view over hundreds of square centimeters at an optical resolution of 18 µm. This system allows the team to observe the behavior and fine anatomical features of numerous freely moving model organisms on multiple spatial scales (e.g., larval zebrafish, fruit flies, slime mold). Overall, by removing the bottlenecks imposed by single-camera image acquisition systems, the MCAM provides a powerful platform for investigating detailed biological features and behavioral processes of small model organisms. Supported by ORIP (R44OD024879), NIEHS, NCI, and NIBIB.
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.
Mendelian Gene Identification through Mouse Embryo Viability Screening
Cacheiro et al., Genome Medicine. 2022.
https://www.doi.org/10.1186/s13073-022-01118-7
The investigators dissected phenotypic similarities between patients and model organisms by assessing the embryonic stage at which homozygous loss of function results in lethality in mice of both sexes obtained from the International Mouse Phenotyping Consortium. Information on knockout mouse embryo lethality can be used to prioritize candidate genes associated with certain disorders. Access to unsolved cases from rare-disease genome sequencing programs allows for the screening of those genes for potentially pathogenic variants, which could lead to a diagnosis and new potential treatment options to inform the management of human disease. Supported by ORIP (UM1OD023221, UM1OD023222, U42OD011174) and NHGRI.
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.
Molecular and Cellular Evolution of the Primate Dorsolateral Prefrontal Cortex
Ma et al., Science. 2022.
https://www.doi.org/10.1126/science.abo7257
The dorsolateral prefrontal cortex (dlPFC) exists only in primates, lies at the center of high-order cognition, and is a locus of pathology underlying many neuropsychiatric diseases. The investigators generated single-nucleus transcriptome data profiling more than 600,000 nuclei from the dlPFC of adult humans, chimpanzees, rhesus macaques, and common marmosets of both sexes. Postmortem human samples were obtained from tissue donors. The investigators’ analyses delineated dlPFC cell-type homology and transcriptomic conservation across species and identified species divergence at the molecular and cellular levels, as well as potential epigenomic mechanisms underlying these differences. Expression patterns of more than 900 genes associated with brain disorders revealed a variety of conserved, divergent, and group-specific patterns. The resulting data resource will help to vertically integrate marmoset and macaque models with human-focused efforts to develop treatments for neuropsychiatric conditions. Supported by ORIP (P51OD011133), NIA, NICHD, NIDA, NIGMS, NHGRI, NIMH, and NINDS.
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.
A Novel DPH5-Related Diphthamide-Deficiency Syndrome Causing Embryonic Lethality or Profound Neurodevelopmental Disorder
Shankar et al., Genetics in Medicine. 2022.
https://www.doi.org/10.1016/j.gim.2022.03.014
Neurodevelopmental disorders (NDDs) affect more than 3% of the pediatric population and often have associated neurologic or multisystem involvement. The underlying genetic etiology of NDDs remains unknown in many individuals. Investigators characterized the molecular basis of NDDs in children of both sexes with nonverbal NDDs from three unrelated families with distinct overlapping craniofacial features. The investigators also used a mouse model of both sexes to determine the pathogenicity of variants of uncertain significance, as well as genes of uncertain significance, to advance translational genomics and provide precision health care. They identified several variants in DPH5 as a potential cause of profound NDD. Their findings provide strong clinical, biochemical, and functional evidence for DPH5 variants as a novel cause of embryonic lethality or profound NDD with multisystem involvement. Based on these findings, the authors propose that “DPH5-related diphthamide deficiency syndrome” is a novel autosomal-recessive Mendelian disorder. Supported by ORIP (K01OD026608, U42OD012210) and NHGRI.
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.