Project description:Lipopeptide biosurfactant producing Bacillus strains have many useful applications in biotechnology and agriculture, based on their emulsifying, surface activity and antimicrobial properties. In the current study, lipopeptide production kinetics, and biocontrol potentials of two new B. velezensis strains, ES1-02 and EFSO2-04 were analyzed and compared with those of commercial strains QST713 and FZB42. ES1-02 and EFSO2-04 showed higher specific growth rates than FZB42, but lower growth rates than QST713. All strains produced surfactin lipopetides, while fengycin production was not observed in ES1-02 and EFSO2-04. Production of fengycin A, B, X and Y were however confirmed in strains QST713 and FZB42. Significant differences were observed in the production of lipopeptides of the iturin family. While ES1-02 and EFSO2-04 produced bacillomycin L, QST713 produced iturin A, and FZB42 produced bacillomycin D. This was in line with the PCR analysis of corresponding genes encoding the identified lipopeptides. Highest surfactin titer of 97.4 mg/L was observed in ES1-02, while QST713 produced highest amount of iturin/bacillomycin (8.5 mg/L). Surfactin isoforms C12 to C17, and iturin/bacillomycin isoforms C11 to C17 were identified by mass spectrometry. ES1-02 and EFSO2-04 showed biocontrol potentials comparable with that of QST713 against Diaporthe spp., while FZB42 showed superior antifungal potentials. Up to 41%, 43%, 47 % and 68.9 % inhibition of D. caulivora were achieved by ES1-02, EFSO2-04, QST713 and FZB42 respectively. Upon exposure to B. velezensis strains, morphological changes to Diaporthe hyphae in form of swellings, distortion, and complete disruption occurred. Interaction of D. longicolla DPC_HOH20 with ES1-02 and EFSO2-04 induced 10-fold and 5-fold increase in surfactin synthesis, respectively. Antagonist interaction with D. longicolla induced significant changes in the proteome of ES1-02 including an increased abundance of several proteins associated with biosynthesis of antimicrobial compounds and fatty acids, while proteins associated with phosphate uptake were decreased in abundance.
Project description:Aggregated α-synuclein (α-SYN) proteins, encoded by the SNCA gene, are hallmarks of Lewy body disease (LBD), affecting multiple brain regions. However, the specific mechanisms underlying α-SYN pathology in cortical neurons, crucial for LBD-associated dementia, remain unclear. Here, we generated human cortical LBD models by differentiating induced pluripotent stem cells (iPSCs) from SNCA triplication LBD patients into cerebral organoids and observed increased levels of pathological α-SYN in these organoids. Single-cell RNA sequencing revealed prominent expression of the SNCA gene in excitatory neurons, which exhibited synaptic and mitochondrial dysfunction, consistent with findings in the cortex of LBD human brains. Furthermore, screening 1280 FDA-approved drugs identified four candidates, which inhibited α-SYN seeding in RT-QuIC assay, reduced α-SYN aggregation and alleviated mitochondrial dysfunction in SNCA triplication iPSC models. Our findings provide valuable insights into the development of cortical LBD models and the discovery of potential drugs targeting α-SYN aggregation.
Project description:Aggregated α-synuclein (α-SYN) proteins, encoded by the SNCA gene, are hallmarks of Lewy body disease (LBD), affecting multiple brain regions. However, the specific mechanisms underlying α-SYN pathology in cortical neurons, crucial for LBD-associated dementia, remain unclear. Here, we generated human cortical LBD models by differentiating induced pluripotent stem cells (iPSCs) from SNCA triplication LBD patients into cerebral organoids and observed increased levels of pathological α-SYN in these organoids. Single-cell RNA sequencing revealed prominent expression of the SNCA gene in excitatory neurons, which exhibited synaptic and mitochondrial dysfunction, consistent with findings in the cortex of LBD human brains. Furthermore, screening 1280 FDA-approved drugs identified four candidates, which inhibited α-SYN seeding in RT-QuIC assay, reduced α-SYN aggregation and alleviated mitochondrial dysfunction in SNCA triplication iPSC models. Our findings provide valuable insights into the development of cortical LBD models and the discovery of potential drugs targeting α-SYN aggregation.
Project description:We report mitochondrial genome (mtDNA) sequences in purified mouse muscle stem cells at different ages. This study identifies changes in the mitochondrial genome of muscle stem cells during aging.
Project description:Parkinson disease (PD) is characterized by extensive loss of A9 dopaminergic (DA) neurons in the substantia nigra pars compacta (SNpc). A strong association has been reported between PD and exposure to mitochondrial toxins such as the environmental pesticides paraquat, maneb, and rotenone. Here, using a robust, patient-derived, stem cell model of PD that allows comparison of -synuclein ( -syn) mutant cells and isogeneic mutation-corrected controls, we identify mitochondrial toxin-induced perturbations specific to A53T -syn mutant A9-DA neurons (hNs). We report a novel molecular pathway whereby basal as well as toxin-induced oxidative and nitrosative stress inhibits the MEF2C-PGC1 transcription network in A53T hNs compared to corrected controls, contributing to mitochondrial dysfunction and apoptotic cell death. Our data provide mechanistic insight into gene-environmental interaction (GxE) in the pathogenesis of PD. Furthermore, using small molecule high-throughput screening, we identify the MEF2C-PGC1 pathway as a new drug target for therapeutic benefit in PD. In the current study, isogenic hiPSCs differing exclusively at a single amino acid (A53T) were exposed to either 2.8uM paraquat in combination with 1uM maneb for 24h or PBS vehicle control. Gene expression profile was analysed to assess the effect of both the genotype and exposure regiment on gene expression.
Project description:We identified two effective fungal elicitors, L01 (Guignardia) and J02 (Diaporthe). The two fungal elicitors might activate Taxol biosynthesis by regulating the MYC2a-controlled JA signaling pathway.