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Goo, Y. A.

Publications and source records attributed to Goo, Y. A..

9 recordsLinked to original sources

Lactational transfer of synthetic oxytocin and sex-specific suppression of neurodevelopmental risk gene networks in the rat prefrontal cortex

Autism spectrum disorder and related neurodevelopmental disorders (NDDs) affect males at two-to-four times the rate of females, yet the environmental contributors to this sex-differentiated vulnerability remain poorly understood. Here, using a clinically translatable postpartum rat model, we show that synthetic oxytocin (OT) administered for postpartum hemorrhage (PPH) prophylaxis ( PPH-OT), a universally administered obstetric medication, undergoes lactational transfer, confirmed by stable isotope-labeled OT and LC-MS/MS, without altering maternal behavior or neonatal cortical OT receptor expression. In offspring, PPH-OT altered ultrasonic vocalizations during dyadic interaction and caused a male-specific reduction in social approach, without affecting other behavioral domains. Sex-stratified RNA-sequencing of the medial prefrontal cortex (mPFC) revealed pronounced transcriptional dimorphism: males showed 1,732 differentially expressed genes versus 693 in females, and a sex-by-treatment interaction contrast identified 1,229 formally sex-differentiated genes. Male mPFC downregulated genes were significantly enriched for high-confidence NDD risk genes across three independent databases -- SFARI score-1 (highest confidence autism genes; OR = 4.56, p = 0.015), DBD autism (OR = 10.34, p = 7.3x10-{superscript 1}{superscript 2}), and SysNDD autosomal dominant (OR = 9.78, p = 8.4x10-) -- including core regulators of cortical circuit assembly (Grin2a, Grin2b, Reln, Tbr1, Mef2c, and Tcf4), an enrichment pattern largely restricted to males. Hypothalamic transcriptional changes were pronounced but showed no enrichment for NDD risk genes, establishing mPFC specificity. These findings identify PPH-OT as a candidate environmental modifier of male neurodevelopmental vulnerability and provide a pressing rationale for prospective investigation of neurodevelopmental outcomes in PPH-OT-exposed children.

neuroscience↗

Compartmentalized glycolysis powers ATP production in primary cilia and engages mitochondria via the phosphoenolpyruvate cycle

Primary cilia are antenna-like sensory and signaling organelles present on most mammalian cells, including glucose-sensing pancreatic {beta}-cells. Here, we show that the local energetic demands of primary cilia require the ATP-producing enzyme pyruvate kinase, with loss of PKm1, but not PKm2, impairing ciliary glycolytic flux. While the entire glycolytic machinery localizes to cilia, our data indicate that mitochondria are a critical source of phosphoenolpyruvate (PEP), the high-energy glycolytic intermediate that drives the pyruvate kinase reaction. Abolishing PCK2, the mitochondrial enzyme that generates PEP, prevents cilia from sensing not only glucose but also the amino acids glutamine and leucine. Finally, by mislocalizing glycolysis, we demonstrate that primary cilia can utilize ATP generated within the cell body when glucose is limiting. These findings indicate that primary cilia, while possessing the capacity for local ATP generation, leverage a ciliary-mitochondrial signaling axis to meet their bioenergetic needs.

cell biology↗

Deciphering acquired resistance mechanisms to sustained auxin-inducible protein degradation in cells and mice

Targeted protein degradation is a favorable strategy for studying the immediate downstream effects of protein loss-of-function. An appealing platform among these technologies is the auxin-inducible degron (AID) system. Although this system has been applied extensively to cell and animal models, degradation resistance to long-term auxin treatment has not been studied. With the advent of the new AID2 system, cellular toxicity due to the high concentrations of auxin required in the original AID1 system is no longer a concern, making it possible to study protein degradation over extended periods. In this study, we derived multiple miniAID-tagged knock-in human cell lines and a Ctcf-miniAID knock-in mouse strain to investigate mechanisms of degradation resistance. We revealed four independent resistance mechanisms, including a nonsense mutation in the CTCF coding sequence that removed the miniAID peptide, a missense point mutation in the miniAID coding region that disrupted ubiquitin complex targeting, and silencing of the OsTIR1 adaptor protein. Resistance to auxin degradation was also acquired in mouse primary CtcfminiAID/miniAID knock-in B-ALL cells through missense mutations of the OsTIR1(F74G) protein in vivo and ex vivo. In summary, our innovative study expands our understanding of the AID system and cautions careful consideration of design for future applications in mammalian system.

cell biology↗

Outer Membrane Vesicles Secreted by Bacteroides fragilis Inhibit CFTR Chloride Secretion by Human Colon Organoids

The goals of this study were to develop a model to study host pathogen interactions in primary human colon organoids and to test the hypothesis that Bacteroides fragilis toxin (BFT-2) secreted in outer membrane vesicles (OMVs) modulates mucosal immunity and CFTR Cl- secretion. Since Bacteroides species reside in mucus, OMVs are likely to represent a mechanism of communication between Bacteroides and the host. Two strains of Bacteroides were studied, Enterotoxigenic Bacteroides fragilis (ETBF), which produces BFT-2, and the non-toxigenic Bacteroides fragilis strain NCTC 9343 (NTBF) that does not produce BFT-2. We also utilized two additional strains of Bacteroides fragilis: one in which bft-2 was knocked out (ETBF {Delta}bft), and one that was engineered to contain bft-2 (NTBF+bft). We report that Bacteroides fragilis OMVs reduced CFTR Cl- secretion but had no effect on tight junction or cell adhesion proteins, transepithelial resistance (TER) or cytokine secretion by primary human colon organoids. NTBF OMVs containing BFT-2 were more effective in reducing CFTR Cl- secretion than NTBF lacking BFT-2. We conclude that OMVs secreted by Bacteroides can be an important mechanism of host pathogen interactions in the colon by reducing CFTR Cl- secretion.

microbiology↗

Spatial proteomics of Onchocerca volvulus with pleomorphic neoplasms shows local and systemic dysregulation of protein expression

Onchocerca volvulus is the agent of onchocerciasis (river blindness) and targeted by WHO for elimination though mass drug administration with ivermectin. A small percentage of adult worms develop pleomorphic neoplasms (PN) that are positively associated with the frequency of ivermectin treatment. Worms with PN have a lower life expectancy and a better understanding about the proteins expressed in PN, and how PN affect protein expression in different tissues could help to elucidate the mechanisms of macrofilaricidal activity of ivermectin. Within a clinical trial of drug combinations that included ivermectin, we detected 24 (5.6%) O. volvulus females with PN by histology of paraffin embedded nodules. To assess the protein inventory of the neoplasms and to identify proteins that may be associated with tumor development, we used laser capture microdissection and highly sensitive mass spectrometry analysis. Neoplasm tissue from three female worms was analyzed, and compared to normal tissues from the body wall, uterus and intestine from the same worms, and to tissues from three females without PN. The healthy females showed all intact embryogenesis. In PN worms, 151 proteins were detected in the body wall, 215 proteins in the intestine, 47 proteins in the uterus and 1,577 proteins in the neoplasms. Only the uterus of one PN female with some stretched intrauterine microfilariae had an elevated number of proteins (601) detectable, while in the uteri of the healthy females 1,710 proteins were detected. Even in tissues that were not directly affected by PN (intestine, body wall), fewer proteins were detected compared to the corresponding tissue of the healthy controls. Immunolocalization of the calcium binding protein OvDig-1 (OVOC8391) confirmed the detection in PN by mass spectrometry. In conclusion we identified proteins that are potentially linked to the development of PN, and systemic dysregulation of protein expression may contribute to worm mortality. Author summaryOnchocerca volvulus, the causative agent of onchocerciasis (river blindness), is targeted for elimination by WHO. The primary strategy involves mass administration of ivermectin. A small proportion of adult female worms develop pleomorphic neoplasms (PN). Here, we used laser capture microdissection and highly sensitive mass spectrometry analysis to determine the protein inventory of PN to identify proteins that may be associated with tumor development. Neoplasm tissue from female worms was analyzed, and compared to normal tissue from the body wall, uterus and intestine from the same worms, and to tissues from females without PN. When compared, PN and healthy control (HC) worms display a different set of proteins, the PN tissue being the one with the highest number of proteins (1,390). From these, 594 were not present in any HC worm tissue. Despite the large number of proteins identified in PN tissue, their low abundance suggests also in PN dysregulation of protein expression. Immunolocalization of a calcium binding protein detected in PN confirmed the mass spectrometry results. In conclusion, we have developed a system to analyze the proteome of O. volvulus from nodule sections and identified proteins that are potentially linked to the development of PN and may contribute to worm mortality.

molecular biology↗

Zur and Zinc Increase Expression of E. coli Ribosomal Protein L31 Through RNA-Mediated Repression of the Repressor L31p

Bacteria can adapt in response to numerous stress conditions. One such stress condition is zinc depletion. The zinc-sensing transcription factor Zur regulates the way enteric bacteria respond to severe changes in zinc availability. Under zinc sufficient conditions, Zn-loaded Zur (Zn2-Zur) is well-known to repress transcription of genes encoding zinc uptake transporters and paralogues of a few ribosomal subunits. Here, we report the discovery and mechanistic basis for the ability of Zur to up-regulate expression of the ribosomal protein L31 in response to zinc in E. coli. Through genetic mutations and reporter gene assays, we find that Zur achieves the up-regulation of L31 through a double repression cascade by which Zur first represses the transcription of L31p, a zinc-lacking paralogue of L31, which in turn represses the translation of L31. Mutational analyses show that translational repression by L31p requires an RNA hairpin structure within the l31 mRNA and involves the N-terminus of the L31p protein. This work uncovers a new genetic network that allows bacteria to respond to host-induced nutrient limiting conditions through a sophisticated ribosomal protein switching mechanism. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=121 SRC="FIGDIR/small/493739v1_ufig1.gif" ALT="Figure 1"> View larger version (42K): org.highwire.dtl.DTLVardef@6a6281org.highwire.dtl.DTLVardef@6942f7org.highwire.dtl.DTLVardef@ab7ce8org.highwire.dtl.DTLVardef@957d55_HPS_FORMAT_FIGEXP M_FIG C_FIG

biochemistry↗

An rRNA fragment in extracellular vesicles secreted by human airway epithelial cells increases the fluoroquinolone sensitivity of P. aeruginosa

Lung infection by antibiotic resistant strains of Pseudomonas aeruginosa is a well-known concern for immunocompromised hosts including people with lung diseases such as cystic fibrosis. We have previously demonstrated that extracellular vesicles (EVs) secreted by primary human airway epithelial cells (AEC) deliver miRNA let-7b-5p to P. aeruginosa where it suppresses biofilm formation and increases sensitivity to beta-lactam antibiotics. In this study we used RNA-seq to characterize the small RNA (sRNA) content of EVs secreted by AEC and demonstrate transfer of multiple distinct RNA fragments from EVs to P. aeruginosa. Bioinformatic predictions reveal that several sRNAs may target all three subunits of the fluoroquinolone efflux pump MexHI-OpmD, an effect predicted to increase antibiotic sensitivity to fluoroquinolone antibiotics. Exposure of P. aeruginosa to EVs resulted in a significant reduction in the protein levels of MexH (-48%), MexI (-50%) and OpmD (-35%). Moreover, EVs reduced planktonic growth of P. aeruginosa in the presence of the fluoroquinolone antibiotic ciprofloxacin by 20%. A mexGHI-opmD deletion mutant of P. aeruginosa phenocopied this increased sensitivity to ciprofloxacin. Finally, we found that a fragment of an 18S rRNA external transcribed spacer that was transferred to P. aeruginosa by EVs was sufficient to reduce planktonic growth of P. aeruginosa in the presence of ciprofloxacin, to reduce the minimum inhibitory concentration (MIC) of P. aeruginosa for ciprofloxacin by over 50%, and to significantly reduce protein levels of MexH and OpmD. In conclusion, an rRNA fragment secreted by AEC in EVs increases the ciprofloxacin sensitivity of P. aeruginosa by targeting and down-regulating the fluoroquinolone efflux pump MexHI-OpmD. A combination of rRNA fragments and ciprofloxacin packaged in nanoparticles or EVs may benefit patients with antibiotic-resistant P. aeruginosa infections. Author SummaryAccording to the World Health Organization and the U.S. Centers for Disease Control and Prevention the development of antibiotic resistant strains of bacteria, including Pseudomonas aeruginosa, are a significant global threat to human health. Thus, development of new approaches to eliminate antibiotic resistant infections is required. In this study, we report that lung epithelial cells secrete extracellular vesicles (EVs) that fuse with and deliver small rRNAs to P. aeruginosa, and that the rRNAs increase the sensitivity of P. aeruginosa to the antibiotic ciprofloxacin by reducing protein levels of the drug efflux pump MexHI-OpmD. We identified one rRNA fragment that by itself significantly reduced the protein levels of MexH and OpmD and increased the ability of ciprofloxacin to kill P. aeruginosa. We propose that developing synthetic vesicles containing a combination of the rRNA that inhibits antibiotic efflux pumps and ciprofloxacin would benefit patients with antibiotic resistant P. aeruginosa infections.

microbiology↗

Coessential Genetic Networks Reveal the Organization and Constituents of a Dynamic Cellular Stress Response

The interrelated programs essential for cellular fitness in the face of stress are critical to understanding tumorigenesis, neurodegeneration, and aging. However, modelling the combinatorial landscape of stresses experienced by diseased cells is challenging, leaving functional relationships within the global stress response network incompletely understood. Here, we leverage genome-scale fitness screening data from 625 cancer cell lines, each representing a unique biological context, to build a network of "coessential" gene relationships centered around master regulators of the response to proteotoxic, oxidative, hypoxic, and genotoxic stress. This approach organizes the stress response into functional modules, identifies genes connecting distinct modules, and reveals mechanisms underlying cellular dependence on individual modules. As an example of the power of this approach, we discover that the previously unannotated HAPSTR (C16orf72) promotes resilience to diverse stressors as a stress-inducible regulator of the E3 ligase HUWE1. Altogether, we present a broadly applicable framework and interactive tool (http://fireworks.mendillolab.org/) to interrogate biological networks using unbiased genetic screens.

genetics↗

USP7 cooperates with NOTCH1 to drive the oncogenic transcriptionalprogram in T cell leukemia

T-cell acute lymphoblastic leukemia (T-ALL) is an aggressive disease, affecting children and adults. Treatments1-6 show high response rates but have debilitating effects and carry risk of relapse5,7,8. Previous work implicated NOTCH1 and other oncogenes1,2,9-20. However, direct inhibition of these pathways affects healthy tissues and cancer alike. Here, we demonstrate that ubiquitin-specific protease 7 (USP7)21-32 controls leukemia growth by stabilizing the levels of the NOTCH1 and JMJD3 demethylase. USP7 is overexpressed T-ALL and is transcriptionally regulated by NOTCH1. In turn, USP7 controls NOTCH1 through deubiquitination. USP7 is bound to oncogenic targets and controls gene expression through H2B ubiquitination and H3K27me3 changes via stabilization of NOTCH1 and JMJD3. We also show that USP7 and NOTCH1 bind T-ALL superenhancers, and USP7 inhibition alters associated gene activity. These results provide a new model for deubiquitinase activity through recruitment to oncogenic chromatin loci and regulation of both oncogenic transcription factors and chromatin marks to promote leukemia. USP7 inhibition33 significantly blocked T-ALL cell growth in vitro and in vivo. Our studies also show that USP7 is upregulated in the aggressive high-risk cases of T-ALL and suggest that USP7 expression might be a prognostic marker in ALL and its inhibition could be a therapeutic tool against aggressive leukemia.

cancer biology↗