Project description:Human neural organoid models have become an important tool for studying neurobiology. In this work, we compared Matrigel to an N-cadherin peptide-functionalized gelatin methacryloyl hydrogel (termed GelMA-Cad) for culturing cortical neural organoids. Specifically, we compare five materials: (1) Matrigel, (2) GelMA-Cad with high crosslinker (HC), (3) GelMA-Cad with low crosslinker (LC), (4) GelMA HC and (5) GelMA LC. We determined that both mechanical properties and peptide presentation can tune cell fate and diversity in gelatin-based matrices during differentiation. Of particular note, cortical organoids cultured in GelMA-Cad produce higher numbers of neurogenic and ciliated radial glia and upper-layer excitatory neurons—an important population for modeling neurodegenerative disease—compared to GelMA and Matrigel controls.
Project description:Abstract: SR12813 is an experimental cholesterol-lowering drug that reduces intracellular cholesterol through accelerated proteasomal degradation of 3-hydroxy-3-methylglutaryl-coenzyme A reductase and is also recognized as a prototypical activator of the pregnane X receptor (PXR, NR1I2). Rifampicin, a clinically used antibiotic, likewise functions as a human PXR agonist. Although PXR-mediated induction of drug metabolism genes has been extensively characterized in hepatocytes and humanized mouse liver, comparatively little is known about the transcriptional effects of these ligands in intestinal and colon cancer cells. Here, we employed RNA sequencing in LS180 colon adenocarcinoma cells to compare transcriptional responses elicited by SR12813 and Rifampicin. LS-180 cells were treated for 48 hours with DMSO, Rifampicin or SR12813.
Project description:We performed proteomic profiling of the brain and retina in 3xTg-AD mouse model of Alzheimer's disease at one month of age to uncover early retinal signatures that may precede disease manifestations.
Project description:The intracellular transport system is an evolutionally conserved, essential, and highly regulated network of organelles and small transport carriers that traffic protein and lipid cargoes within the cell. The Conserved Oligomeric Golgi (COG) complex is the major Golgi Multisubunit Tethering Complex. Its key function is orchestration of SNARE mediated fusion of cargo carriers at the Golgi. We hypothesized the depletion of the major Golgi SNAREs GS28 (GOSR1) and GS15 (BET1L) due to COG malfunction is the major contributor to COG-related glycosylation defects. To test this, we created single, double and triple knockouts (KO) of Golgi SNAREs in HEK293T cells and analyzed the resulting mutants using a comprehensive set of biochemical, mass-spectrometry (MS) and microscopy approaches. Deletion of GS28 significantly affected GS15, but not the other two partners, STX5 and YKT6. Surprisingly, our analysis revealed that COG dysfunction is more deleterious for Golgi function than disrupting the canonical Golgi SNARE complex indicating the existence of an adaption mechanism. Indeed, quantitative mass-spectrometry analysis of STX5-interacting proteins revealed unexpected flexibility in Golgi SNARE pairing in mammalian cells. We uncovered two novel non-canonical Golgi SNARE complexes – STX5/SNAP29/VAMP7 and STX5/VTI1B/GS15/YKT6 which were increased in GS28 KO cells. Upon GS28 deletion, SNAP29 remarkably localized to the Golgi. Merely mislocalizing STX5 from Golgi abolished the SNARE substitution causing dramatic glycosylation defects. Our data points to the remarkable plasticity in the intra-Golgi membrane fusion machinery and places STX5 as the only essential Golgi Qa-SNARE.
Project description:Better biomarkers to predict death early in acute liver failure (ALF) are needed. To that end, we obtained early (study day 1) and later (day 3) serum samples from transplant-free survivors (n=28) and non-survivors (n=30) of acetaminophen (APAP)-induced ALF from the NIH-sponsored Acute Liver Failure Study Group, and from control volunteers (n=10). To identify proteins that increase early in serum during ALF, we selected individuals from this cohort for whom ALT was lower on day 1 than day 3, indicating a time point before the peak of injury (n=10/group). We then performed untargeted proteomics on their day 1 samples. Out of 1,682 quantifiable proteins, 79 were elevated ≥4-fold in ALF patients vs. controls and 23 of those were further elevated ≥4-fold in non-survivors vs. survivors, indicating potential to predict death. Interestingly, the biomarker with best performance was LDH. To confirm the prognostic potential of LDH, we measured activity in all day 1 and 3 samples from all 58 ALF patients. LDH was elevated in the non-survivors vs. survivors on both days. In addition, receiver operating characteristic (ROC) curve analyses revealed that LDH alone performed similarly to the model for end-stage liver disease (MELD), while a combination of MELD and LDH outperformed either alone. Finally, Upstream Analysis of our proteomics data indicated activation of LKB1-AMPK signaling in liver regeneration after APAP overdose and we confirmed that in mice. Overall, we conclude LDH can predict death in APAP-induced ALF and that LKB1-AMPK signaling may be a promising therapeutic target to improve survival.
Project description:Human neural organoid models have become an important tool for studying neurobiology. In this work, we compared Matrigel to an N-cadherin peptide-functionalized gelatin methacryloyl hydrogel (termed GelMA-Cad) for culturing cortical neural organoids. Specifically, we compare five materials: (1) Matrigel, (2) GelMA-Cad with high crosslinker (HC), (3) GelMA-Cad with low crosslinker (LC), (4) GelMA HC and (5) GelMA LC. We profiled these organoids at the earliest stages to understand potential differences in radial glia formation.
Project description:Nuclear receptor binding SET domain protein 3 (NSD3), a gene located within the 8p11-p12 amplicon frequently detected in cancers, encodes a chromatin modulator and an attractive onco-target. However, agent that can effectively suppress the NSD3-mediated oncogenic actions is currently lacking. We report an NSD3-targeting proteolysis targeting chimera (PROTAC), termed MS9715, which achieves effective and specific depletion of NSD3 and interacting partners (including cMyc) in tumor cells. MS9715-induced NSD3 degradation relies on BI-9321, an antagonist module binding the PWWP1 domain of NSD3, and VHL, which is chemically conjugated to BI-9321 via a linker and VHL ligand module. Importantly, compared to BI-9321, a recently disclosed NSD3 antagonist, MS9715 is more potent in suppressing growth of the NSD3-dependent hematological cancer including models of MLL-rearranged acute myeloid leukemia (AML) and B-cell acute lymphoblastic leukemia (B-ALL) and multiple myeloma (MM), and uniquely mediate simultaneous depletion of cellular NSD3 and cMyc. Transcriptome profiling further demonstrates effective actions of MS9715 but not BI-9321 in suppressing both NSD3- and cMyc-associated gene-expression programs, a phenomenon reminiscent of the CRISPR/cas9-mediated knockout (KO) of NSD3. Together, this study reports a first-in-class NSD3 PROTAC/degrader suitable for co-suppressing NSD3- and cMyc-related oncogenic nodes in cancer cells, suggesting a novel therapeutic strategy.
Project description:The adaptive response to extreme endurance exercise might involve transcriptional and translational regulation by microRNAs (miRNAs). Therefore, the aim of this study was to define an integrative analysis of blood transcriptome and miRNome in horses before and after a long endurance ride (160 km) using equine microarrays. A total of 2,453 genes and 162 miRNAs were found to be differentially expressed (DEG) between animals at rest and after the endurance ride. To gain understanding of the biological functions regulated by the differentially expressed miRNA, we used a hypergeometric test analysis. Notably, we detected 42 differentially expressed miRNAs that putatively regulate a total of 350 depleted DEGs, involved in glucose metabolism, fatty acid oxidation, mitochondrion biogenesis, and immune response pathways. Graphical Gaussian models in an independent validation set of animals confirmed that 4 miRNAs could be strong candidate regulatory molecules for endurance exercise adaptation. This study represents, to the best of our knowledge, the first integrated comprehensive overview of the miRNA-mRNA co-regulation networks that may play a central role in controlling post-transcriptomic regulations during endurance exercise in horses. Sixty-one Arabian or half-breed Arabian horses (20 females and 41 geldings) aged 10 ± 2 years (±SEM) were recruited on voluntary basis of the owner on three 160 km endurance rides.
Project description:Cardiac myocyte-specific ERalpha KO mice were generated to assess the role of ERα in the heart. Female ERαHKO mice displayed a modest cardiac phenotype, but unexpectedly, an the most striking obesity phenotype developed was obesity in female ERαHKO but not male ERαHKO mice. In female ERαHKO mice we identified cardiac dysfunction, mild glucose and insulin intolerance, and reduced ERα gene expression in skeletal muscle and white adipose tissue (WAT). RNA-seq analysis was conducted on the ventricles and WAT of male and female ERαHKO mice to further elucidate the transcriptomic alterations associated with the shift in metabolic profiles in the tissues of interest.
Project description:Purpose: Determination of inter- and intra-day variations in tear flow rate, tear fluid protein concentration as well as protein composition regarding their impact for future biomarker studies.Methods: Tear fluid was collected non-invasively from 18 healthy subjects performing Schirmer tests at four different time points repetitive in a period of two days. The tear flow rate with Schirmer test strips was measured. Proteins were extracted from strips and quantified using amino acid analysis. Protein composition was analyzed by data-independent (DIA) based mass spectrometry. To exclude any impairments to health, volunteers underwent a detailed neurological as well as an ophthalmological examination.Results: Whether tear fluid was collected from OS or OD did not affect the tear flow rate (p ≈ 0.63) or protein concentration (p ≈ 0.97) of individual subjects. Moreover, protein concentration was independent from the tear volume, so that a change in volume would only have an effect on total protein amount. When the examination days were compared, investigation of tear flow rate (p ≈ 0.001) and protein concentration (p ≈ 0.0003) indicated significant differences. Further mass spectrometric analysis of tear fluid revealed eleven differentially regulated proteins when comparing both examination days. Conclusion: Our findings provide evidence of inter-day variation in tear flow rate, tear proteome concentration and composition in healthy subjects, suggesting that inter-day variation need to be taken into consideration in biomarker research of tear fluid. Identified proteins were assigned to functions in the immune response, oxidative and reducing processes, as well as mannose metabolism.