Selected Grantee Publications
A Chromosome-Level Genome of Astyanax mexicanus Surface Fish for Comparing Population-Specific Genetic Differences Contributing to Trait Evolution
Warren et al., Nature Communications. 2021.
https://pubmed.ncbi.nlm.nih.gov/33664263/
Identifying the genetic factors that underlie complex traits is central to understanding the mechanistic underpinnings of evolution. Cave-dwelling Astyanax mexicanus populations are well adapted to subterranean life and many populations appear to have evolved troglomorphic (morphological adaptation of an animal to living in the constant darkness of caves) traits independently, while the surface-dwelling populations can be used as a proxy for the ancestral form. Warren et al. present a high-resolution, chromosome-level surface fish genome, enabling the first genome-wide comparison between surface fish and cavefish populations. Using this resource, they performed quantitative trait locus (QTL) mapping analyses and found new candidate genes for eye loss (dusp26). They also generated the first genome-wide evaluation of deletion variability across cavefish populations to gain insight into this potential source of cave adaptation. The surface fish genome reference now provides a more complete resource for comparative, functional and genetic studies of drastic trait differences within a species. Supported by ORIP (R24OD011198), NIA, NICHD, NIGMS, amd NIDCR.
Autologous Transplant Therapy Alleviates Motor and Depressive Behaviors in Parkinsonian Monkeys
Tao et al., Nature Medicine. 2021.
https://www.nature.com/articles/s41591-021-01257-1
Generation of induced pluripotent stem cells (iPSCs) enables standardized of dopamine (DA) neurons for autologous transplantation therapy to improve motor functions in Parkinson disease (PD). Adult male rhesus PD monkeys receiving autologous, but not allogenic, transplantation exhibited recovery from motor and depressive signs of PD over a 2-year period without immunosuppressive therapy. Mathematical modeling showed correlations between surviving DA neurons with PET signal intensity and behavior recovery regardless of autologous or allogeneic transplant, suggesting a predictive power of PET and motor behaviors for surviving DA neuron number. The results demonstrate favorable efficacy of the autologous transplant approach to treat PD. Supported by ORIP (P51OD011106) NINDS, and NICHD.
Natural Killer Cells Activated Through NKG2D Mediate Lung Ischemia-Reperfusion Injury
Calabrese et al., Journal of Clinical Investigation. 2021.
https://www.jci.org/articles/view/137047
Pulmonary ischemia-reperfusion injury (IRI) causes early mortality and has no effective therapies. While natural killer (NK) cells are innate lymphocytes capable of recognizing injured cells, their roles in acute lung injury are incompletely understood. Here, investigators demonstrated that NK cells were increased in frequency and cytotoxicity in 2 different IRI mouse models. They showed that NK cells trafficked to the lung tissue from peripheral reservoirs and were more mature within lung tissue. Acute lung ischemia-reperfusion injury was blunted in a NK cell–deficient mouse strain but restored with adoptive transfer of NK cells. In human lung tissue, NK cells were increased at sites of ischemia-reperfusion injury and activated NK cells were increased in prospectively-collected human bronchoalveolar lavage in subjects with severe IRI. These data support a causal role for recipient peripheral NK cells in pulmonary IRI via NK cell NKG2D receptor ligation. Therapies targeting NK cells may hold promise in acute lung injury. Supported by ORIP (S10OD026940), NHLBI, and NIDDK.
Increased Proviral DNA in Circulating Cells Correlates With Plasma Viral Rebound in SIV-Infected Rhesus Macaques after Antiretroviral Therapy Interruption
Ziani et al., Journal of Virology. 2021.
https://jvi.asm.org/content/early/2021/01/05/JVI.02064-20
Investigators longitudinally tracked dynamic decay of cell-associated viral RNA/DNA in systemic and lymphoid tissues in SIV-infected rhesus macaques on prolonged combined antiretroviral therapy (cART) to evaluate predictors of viral rebound after treatment cessation. Suppressive cART substantially reduced plasma SIV RNA, cell-associated unspliced, and multiply spliced SIV RNA to undetectable levels, yet viral DNA remained detectable in systemic tissues and lymphoid compartments throughout cART. A rapid increase of integrated proviral DNA in peripheral mononuclear cells was detected once cART was withdrawn, accompanied by the emergence of detectable plasma viral load. The increase of peripheral proviral DNA post cART interruption correlated with the emergence and degree of viral rebound. These results suggest that measuring total viral DNA in SIV infection may be a relatively simple surrogate marker of reservoir size, and may predict viral rebound after treatment interruption, and inform treatment strategies. Supported by ORIP (P51OD011104), NIAID and NICHD.
A Frog with Three Sex Chromosomes that Co-Mingle Together in Nature: Xenopus tropicalis Has a Degenerate W and a Y that Evolved from a Z Chromosome
Furman et al., PLOS Genetics. 2020.
https://pubmed.ncbi.nlm.nih.gov/33166278/
Genetic systems governing sexual differentiation vary among species. Furman et al. investigated a frog with three sex chromosomes, the Western clawed frog, Xenopus tropicalis. They demonstrate that natural populations from the western and eastern edges of Ghana have a young Y chromosome, and that a male-determining factor on this Y chromosome is in a similar genomic location as a previously known female-determining factor on the W chromosome. Their findings are consistent with theoretical expectations associated with recombination suppression on sex chromosomes and demonstrate that several characteristics of old and established sex chromosomes can arise well before they become cytogenetically distinguished. Supported by ORIP (P40OD010997) and NICHD.
Lipocalin-2 Is an Anorexigenic Signal in Primates
Petropoulou et al., eLife. 2020.
https://doi.org/10.7554/eLife.58949
The hormone lipocalin-2 (LCN2) suppresses food intake in mice. Researchers demonstrated that LCN2 increases after a meal and reduces hunger in people with normal weight or overweight, but not in obese individuals. The researchers also showed that LCN2 crosses the blood-brain barrier and binds to the hypothalamus in vervet monkeys. LCN2 was found to bind to the hypothalamus in human, baboon, and rhesus macaque brain sections. When injected into vervets, LCN2 suppressed food intake and lowered body weight without toxic effects in short-term experiments. These findings lay the groundwork to investigate whether LCN2 might be a useful treatment for obesity. Supported by ORIP (P40OD010965), NCATS, NIDDK, NIA, and NHLBI.
Estrogen Acts Through Estrogen Receptor 2b to Regulate Hepatobiliary Fate During Vertebrate Development
Chaturantabut et al., Hepatology. 2020.
https://aasldpubs.onlinelibrary.wiley.com/doi/full/10.1002/hep.31184
During liver development, bipotent progenitor cells differentiate into hepatocytes and biliary epithelial cells to ensure a functional liver. The developmental cues controlling the differentiation of committed progenitors into these cell types are not completely understood. These authors report an essential role for estrogenic regulation in vertebrate liver development to affect hepatobiliary fate decisions. The studies identify17β-estradiol (E2), nuclear estrogen receptor 2b (esr2b), and downstream bone morphogenetic protein (BMP) activity as important regulators of hepatobiliary fate decisions during vertebrate liver development. These results have significant implications for liver development in infants exposed to abnormal estrogen levels or estrogenic compounds during pregnancy. Supported by ORIP (R24OD017870) and NIDDK.
Fructose Stimulated De Novo Lipogenesis Is Promoted by Inflammation
Jelena et al., Nature Metabolism. 2020.
https://pubmed.ncbi.nlm.nih.gov/32839596
Non-alcoholic fatty liver disease (NAFD) affects 30% of adult Americans. While NAFD starts as simple steatosis with little liver damage, its severe manifestation as non-alcoholic steatohepatitis (NASH) is a leading cause of liver failure, cirrhosis, and cancer. Fructose consumption is proposed to increase the risk of hepatosteatosis and NASH. Excessive intake of fructose causes barrier deterioration and low-grade endotoxemia. Using a mouse model, the study examined the mechanism of how fructose triggers these alterations and their roles in hepatosteatosis and NASH pathogenesis. The results demonstrated that microbiota-derived Toll-like receptor (TLR) agonists promote hepatosteatosis without affecting fructose-1-phosphate (F1P) and cytosolic acetyl-CoA. Activation of mucosal-regenerative gp130 signaling, administration of the YAP-induced matricellular protein CCN1 or expression of the antimicrobial peptide Reg3b (beta) counteract fructose-induced barrier deterioration, which depends on endoplasmic-reticulum stress and subsequent endotoxemia. Endotoxin engages TLR4 to trigger TNF production by liver macrophages, thereby inducing lipogenic enzymes that convert F1P and acetyl-CoA to fatty acid in both mouse and human hepatocytes. The finding may be of relevance to several common liver diseases and metabolic disorders. Supported by ORIP (S10OD020025), NCI, NIEHS, NIDDK, NIAID, and NIAAA.
Fluorescence-Based Sorting of Caenorhabditis elegans via Acoustofluidics
Zhang et al., Lab on a Chip. 2020.
The authors present an integrated acoustofluidic chip capable of identifying worms of interest based on expression of a fluorescent protein in a continuous flow and then separate them in a high-throughput manner. Utilizing planar fiber optics, their acoustofluidic device requires no temporary immobilization of worms for interrogation/detection, thereby improving the throughput. The device can sort worms of different developmental stages (L3 and L4 stage worms) at high throughput and accuracy. In their acoustofluidic chip, the time to complete the detection and sorting of one worm is only 50 ms, which outperforms nearly all existing microfluidics-based worm sorting devices. Supported by ORIP (R43OD024963), NIEHS, and NIDDK.