Project description:We proposed that DNA recombination/repair processes play a role in memory formation. Here, we used microarray analysis of rat amygdala genes to identify possible DNA recombination/repair factors involved in memory consolidation of conditioned taste aversion (CTA). Among the genes that showed statistically significant differential expression, we identified fen-1, encoding a flap-structure specific DNA endonuclease. Amygdalar fen-1 mRNA induction was associated to the illness component of CTA, since it could be observed by the pairing of a flavor and gastrointestinal illness, by the illness itself, but not by the presentation of the flavor alone. No CTA related induction of fen-1 expression was observed in the insular cortex. Importantly, functional validation studies demonstrated that amygdalar suppression of fen-1 expression impaired memory consolidation of CTA. Overall, our studies helped identify a new DNA recombination/repair candidate factor involved in memory formation of aversive experiences.
Project description:Bruton’s tyrosine kinase (BTK) is an intracellular signaling enzyme that regulates B cell and myeloid cell functions. Due to its involvement in both innate and adaptive immune compartments, inhibitors of BTK have emerged as a therapeutic option in autoimmune disorders such as multiple sclerosis (MS). Brain penetrant small molecule BTK inhibitors may also help to address compartmentalized neuroinflammation which is proposed to underlie MS disease progression. BTK is expressed by microglia, the resident innate immune cells of the brain, however the precise roles of microglial BTK and the impact of BTK inhibitors on microglial functions is still being elucidated. Much research to date has also focused on the effects of BTK inhibitors using rodent disease models. Here we characterize the pharmacological and functional properties of fenebrutinib (FEN), a potent, highly selective, noncovalent, reversible BTK inhibitor, in human microglia and complex human brain cell systems including brain organoids. We find that FEN blocks the effects of microglial FcγR activation including cytokine and chemokine release, microglial clustering and neurite damage in diverse human brain cell systems. Gene expression analyses identified pathways linked to inflammation, matrix metalloproteinase production and cholesterol metabolism that were modulated by FEN treatment. In contrast, FEN had no significant impact on human microglial pathways linked to TLR4 or NLRP3 signaling nor myelin phagocytosis. Our study increases the understanding of BTK functions in human microglial signaling relevant to MS pathogenesis and suggests that FEN could attenuate detrimental microglial activity associated with FcγR activation in MS patients.
Project description:We proposed that DNA recombination/repair processes play a role in memory formation. Here, we used microarray analysis of rat amygdala genes to identify possible DNA recombination/repair factors involved in memory consolidation of conditioned taste aversion (CTA). Among the genes that showed statistically significant differential expression, we identified fen-1, encoding a flap-structure specific DNA endonuclease. Amygdalar fen-1 mRNA induction was associated to the illness component of CTA, since it could be observed by the pairing of a flavor and gastrointestinal illness, by the illness itself, but not by the presentation of the flavor alone. No CTA related induction of fen-1 expression was observed in the insular cortex. Importantly, functional validation studies demonstrated that amygdalar suppression of fen-1 expression impaired memory consolidation of CTA. Overall, our studies helped identify a new DNA recombination/repair candidate factor involved in memory formation of aversive experiences. Two comparisons were established between the cRNA samples: CTA versus Flavor-only and CTA versus Toxin-only. For each comparison, the microarray experiment was repeated four times using new biological samples, each consisting of a sample pool from 3 animals. Two of the four biological replicates were performed as dye-swaps in order to correct for dye bias effects.
Project description:The common house spider Parasteatoda tepidariorum is a chelicerate model organism for studying developmental mechanisms and their evolution in arthropods. In contrast to the well-studied model insect, Drosophila melanogaster, embryos of the spider undergo patterning in a cellular environment from early stages (at least after the number of the nuclei increase to 16). Use of spider embryos provide new opportunities to understand the evolution of developmental mechanisms underlying arthropod body plans. This analysis aims to generate genome-scale, developmental profiles of gene expression in embryos of the spider P. tepidariorum, which facilitate a wide range of studies using this spider species.
Project description:The lipid raft resident protein, MAL2, has been implicated as contributing to the pathogenesis of several malignancies, including breast cancer, but the underlying mechanism for its effects on tumorigenesis is unknown. Here, we show that MAL2-mediated lipid raft formation leads to HER2 plasma membrane retention and enhanced HER2 signaling in breast cancer cells. We employed proximity ligation assays (PLA) to define physical interactions between HER2 and MAL2 in lipid rafts and super-resolution structured illumination microscopy (SR-SIM imaging) to determine the structural organization of the HER2/Ezrin/NHERF1/PMCA2 protein complex. Formation of this protein complex maintains low intracellular calcium concentrations in the vicinity of the plasma membrane. Importantly, we also observed enhanced HER2-MAL2 protein interactions in lipid rafts in trastuzumab-resistant breast cancer cells. Our findings suggest that MAL2 is crucial for lipid raft formation, HER2 signaling and HER2 membrane stability in breast cancer cells, suggesting MAL2 as a potential therapeutic target.
Project description:This SuperSeries is composed of the following subset Series: GSE31525: Spider mite preliminary feeding experiment with mites reared on bean and two Arabidopsis thaliana accessions GSE31527: Developmental stage-specific gene expression in the two-spotted spider mite (Tetranychus urticae) GSE32005: Developmental stage-specific small RNA composition in the two-spotted spider mite (Tetranychus urticae) GSE32009: Transcriptional responses of the two-spotted spider mite (Tetranychus urticae) after transfer to different plant hosts Refer to individual Series