Project description:Mitochondrial Ca2+ ([Ca2+]M) uptake through its Ca2+ uniporter (MCU) is central to many cell functions such as bioenergetics, spatiotemporal organization of Ca2+ signals, and apoptosis. MCU activity is regulated by several intrinsic proteins including MICU1, MICU2, and EMRE. While significant details about the role of MICU1, MICU2, and EMRE in MCU function have emerged recently, a key challenge for the future experiments is to investigate how these regulatory proteins modulate mitochondrial Ca2+ influx through MCU in intact cells under pathophysiological conditions. This is further complicated by the fact that several variables affecting MCU function change dynamically as cell functions. To overcome this void, we develop a data-driven model that closely replicates the behavior of MCU under a wide range of cytosolic Ca2+ ([Ca2+]C), [Ca2+]M, and mitochondrial membrane potential values in WT, MICU1 knockout (KO), and MICU2 KO cells at the single mitochondrion and whole-cell levels. The model is extended to investigate how MICU1 or MICU2 KO affect mitochondrial function. Moreover, we show how Ca2+ buffering proteins, the separation between mitochondrion and Ca2+-releasing stores, and the duration of opening of Ca2+-releasing channels affect mitochondrial function under different conditions. Finally, we demonstrate an easy extension of the model to single channel function of MCU.
Project description:To survey the proteomic differences between WT and Slc37a2 knockout osteoclasts at the whole cell and secretory lysosome levels, we used superparamagnetic iron oxide nanoparticles (SPIONs) to enrich for these endo-lysosomal-related organelles from murine osteoclast cultures. Briefly, large scale murine bone marrow monocyte (BMM)-derived osteoclast cultures were ‘pulsed’ with SPIONs to encourage uptake into endosomes and then ‘chased’ into secretory lysosomes upon the convergence of SPION-loaded endosomes with lysosomes and secretory pathways. Following the ‘pulse-chase’, osteoclasts were homogenized, SPION-loaded organelles captured-from post-nuclear supernatants using magnetic columns, and enriched organelles as well as homogenates eluted and processed for 1D in-gel digestion and mass spectrometry. The samples presented here correspond to the proteome of WT and Slc37a2 knockout homogenates with secretory lysosome proteomes have been shared in another submission.
Project description:To survey the proteome of osteoclast secretory lysosomes, we used superparamagnetic iron oxide nanoparticles (SPIONs) to enrich for these endo-lysosomal-related organelles from murine osteoclast cultures. Briefly, large scale murine bone marrow monocyte (BMM)-derived osteoclast cultures were ‘pulsed’ with SPIONs to encourage uptake into endosomes and then ‘chased’ into secretory lysosomes upon the convergence of SPION-loaded endosomes with lysosomes and secretory pathways. Following the ‘pulse-chase’, osteoclasts were homogenized, SPION-loaded organelles captured-from post-nuclear supernatants using magnetic columns, and enriched organelles eluted and processed for 1D in-gel digestion and mass spectrometry.
Project description:IntroductionDuchenne muscular dystrophy (DMD) is a hereditary neuromuscular disorder caused by mutation in the dystrophin gene (DMD) on the X chromosome. Female DMD carriers occasionally exhibit symptoms such as muscle weakness and heart failure. Here, we investigated the characteristics and representativeness of female DMD carrier (DMD-XKOXWT) pigs as a suitable disease model.MethodsIn vitro fertilization using sperm from a DMD-XKOY↔XWTXWT chimeric boar yielded DMD-XKOXWT females, which were used to generate F2 and F3 progeny, including DMD-XKOXWT females. F1-F3 piglets were genotyped and subjected to biochemical analysis for blood creatine kinase (CK), aspartate aminotransferase, and lactate dehydrogenase. Skeletal muscle and myocardial tissue were analyzed for the expression of dystrophin and utrophin, as well as for lymphocyte and macrophage infiltration.ResultsDMD-XKOXWT pigs exhibited various characteristics common to human DMD carrier patients, namely, asymptomatic hyperCKemia, dystrophin expression patterns in the skeletal and cardiac muscles, histopathological features of skeletal muscle degeneration, myocardial lesions in adulthood, and sporadic death. Pathological abnormalities observed in the skeletal muscles in DMD-XKOXWT pigs point to a frequent incidence of pathological abnormalities in the musculoskeletal tissues of latent DMD carriers. Our findings suggest a higher risk of myocardial abnormalities in DMD carrier women than previously believed.ConclusionsWe demonstrated that DMD-XKOXWT pigs could serve as a suitable large animal model for understanding the pathogenic mechanism in DMD carriers and developing therapies for female DMD carriers.
Project description:Transcriptional profiling of mouse lung tumors comparing Dnmt3a KO/K-ras G12D mutant with Dnmt3a WT/K-ras G12D mutant. The goal is to search for the difference of mRNA abundance between Dnmt3a KO and WT tumors.
Project description:Transcriptional profiling of mouse lung tumors comparing Dnmt3a KO/K-ras G12D mutant with Dnmt3a WT/K-ras G12D mutant. The goal is to search for the difference of mRNA abundance between Dnmt3a KO and WT tumors. Two-condition experiment, KO vs. WT tissure. Biological replicates: 12.