Cdk8/CDK19 Promotes Mitochondrial Fission Through Drp1 Phosphorylation and Can Phenotypically Suppress Pink1 Deficiency in Drosophila
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Pink1 is a mitochondrial kinase implicated in Parkinson’s disease and is conserved among humans, rodents, and flies. In this study, researchers found that Cdk8 in Drosophila (i.e., the orthologue of vertebrate CDK8 and CDK19) promotes the phosphorylation of Drp1 (i.e., a protein required for mitochondrial fission) at the same residue as Pink1. Cdk8 is expressed in both the cytoplasm and nucleus, and neuronal loss of Cdk8 reduces fly life span and causes bang sensitivity and elongated mitochondria in both muscles and neurons.
Consistent Survival in Consecutive Cases of Life-Supporting Porcine Kidney Xenotransplantation Using 10GE Source Pigs
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Xenotransplantation offers potential for addressing organ donor shortages, and the U.S. Food and Drug Administration recently issued guidance on a regulatory path forward. Researchers have performed studies in this area, but concerns have been expressed about safe clinical translation of their results (e.g., survival, preclinical procurement, immunosuppression, clinical standards of care). In this study, the authors report consistent survival in consecutive cases of kidney xenotransplantation from pigs (male and female) to baboons (male and female).
Induction of Durable Remission by Dual Immunotherapy in SHIV-Infected ART-Suppressed Macaques
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The latent viral reservoir is established within the first few days of HIV infection and remains a barrier to a clinical cure. Researchers characterized the effects of a combined Anktiva (N-803) treatment with broadly neutralizing antibodies (bNAbs) using male and female rhesus macaques infected with simian–human immunodeficiency virus infection. Their data suggest that these agents synergize to enhance CD8+ T-cell function, particularly when multiple bNAbs are used.
Trade-Offs Shaping Transmission of Sylvatic Dengue and Zika Viruses in Monkey Hosts
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Mosquito-borne dengue (DENV) and Zika (ZIKV) viruses originated in Old World sylvatic (forest) cycles involving monkeys and canopy-living Aedes mosquitoes. Both viruses spilled over into human transmission and were translocated to the Americas, opening a path for spillback into neotropical sylvatic cycles. This article reports that the trade-offs that shape within-host dynamics and transmission of these viruses are lacking, hampering efforts to predict spillover and spillback.
Pigs in Transplantation Research and Their Potential as Sources of Organs in Clinical Xenotransplantation
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The pig has now gained importance as a potential source of organs for clinical xenotransplantation. When an organ from a wild-type (i.e., genetically unmodified) pig is transplanted into an immunosuppressed nonhuman primate, a vigorous host immune response causes hyperacute rejection (within minutes or hours). This response has been largely overcome by (1) extensive gene editing of the organ-source pig and (2) administration to the recipient of novel immunosuppressive therapy based on blockade of the CD40/CD154 T-cell costimulation pathway.
Epigenetic MLH1 Silencing Concurs With Mismatch Repair Deficiency in Sporadic, Naturally Occurring Colorectal Cancer in Rhesus Macaques
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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.
Biological Activities of a New Crotamine-like Peptide from Crotalus oreganus helleri on C2C12 and CHO Cell Lines, and Ultrastructural Changes on Motor Endplate and Striated Muscle
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Crotamine and crotamine-like peptides are non-enzymatic polypeptides found in high concentration in the Crotalus genus venom. Helleramine was isolated and purified from the venom of the rattlesnake, Crotalus oreganus helleri. Purified helleramine increased intracellular Ca2+ in Chinese Hamster Ovary (CHO) cell line, inhibited cell viability of C2C12 (immortalized skeletal myoblast) and promoted early apoptosis and cell death.
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
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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.
Lipocalin-2 Is an Anorexigenic Signal in Primates
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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.
Epidemiological and Molecular Characterization of a Novel Adenovirus of Squirrel Monkeys After Fatal Infection During Immunosuppression
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Adenoviruses frequently cause upper respiratory tract infections, often causing disseminated disease in immunosuppressed patients. A novel adenovirus was identified, squirrel monkey adenovirus 1 (SqMAdV-1), as the cause of a fatal infection in an immunocompromised squirrel monkey (Saimiri boliviensis). A nucleotide polymorphism at the stop codon of the DNA polymerase gene results in a 126 amino acid extension at the carboxy terminus. A single adenovirus variant, SqMAdV-3, has similarity to tufted capuchin (Sapajus apella) adenoviruses.