Grey Bruce provincial police say the OPP canine unit found human remains in Meaford, and one person is under arrest.

The Ontario government gave garden centres and nurseries the green light to open their doors to the public on Friday.

Vancouver resident Hugo Huynh says he's never seen the man who got out of a minivan outside his home early Monday morning and uprooted the young tree.

B.C. recorded 29 more cases of COVID-19 and one more death over the last 24 hours, provincial health officials announced Friday.

Landlords who are missing thousands of dollars in rent or who find their properties damaged or strewn with garbage are concerned some tenants are taking advantage of the eviction ban put in place during the pandemic.

The following article, Donald Trump Jr. Offers To Walk Bride-to-Be Down The Aisle After Liberal Parents Refuse To Attend Her Wedding Because Fiance Is A Conservative, was first published on 100PercentFedUp.com.

TDS or Trump Derangement Syndrome brings out the worst in a lot of people. One young Texan girl’s story of her intolerant parents who refuse to attend her wedding because she’s marrying a conservative, however, is a new low. Lawyer and conservative civil rights activist, Rogan O’Handley tweeted a Tik Tok video of a Texan […]

Continue reading: Donald Trump Jr. Offers To Walk Bride-to-Be Down The Aisle After Liberal Parents Refuse To Attend Her Wedding Because Fiance Is A Conservative ...

The following article, Univ of Pittsburg Researcher, China Native, Dr. Bing Liu, “On the verge” of COVID19 Breakthrough Is Murdered…Alleged Gunman, Hao Gu, Kills Himself, was first published on 100PercentFedUp.com.

A 37-year-old China native and "outstanding researcher" at the University of Pittsburgh...

Continue reading: Univ of Pittsburg Researcher, China Native, Dr. Bing Liu, “On the verge” of COVID19 Breakthrough Is Murdered…Alleged Gunman, Hao Gu, Kills Himself ...

The following article, BREAKING: Sen Marsha Blackburn Introduces Stop COVID Act…Allowing US Citizens To Sue Communist China For Damage They’ve Inflicted On Our Nation, was first published on 100PercentFedUp.com.

Yesterday, Senator Marsha Blackburn (R-TN), along with Senator Martha McSally (R-AZ) introduced the Stop COVID Act, giving Americans the ability to sue Communist China for the damage they’ve inflicted on our nation. Senator Blackburn appeared on Fox News with host Judge Jeanine where she explained the act to Jeanine Pirro. Blackburn told the Fox News […]

Continue reading: BREAKING: Sen Marsha Blackburn Introduces Stop COVID Act…Allowing US Citizens To Sue Communist China For Damage They’ve Inflicted On Our Nation ...

The following article, BREAKING: 43-Yr-Old Father Of 9, Dollar Store Sec Guard, Shot DEAD While Allegedly Trying To Enforce MI Gov Whitmer’s Face Covering Exec Order, was first published on 100PercentFedUp.com.

Will the mainstream media report about the senseless death of a 43-year-old father of nine, who would have been alive today if it were not for VP wannabe, Gretchen Whitmer's executive order that forced him to respond to a customer not wearing a face mask? 

Continue reading: BREAKING: 43-Yr-Old Father Of 9, Dollar Store Sec Guard, Shot DEAD While Allegedly Trying To Enforce MI Gov Whitmer’s Face Covering Exec Order ...

The following article, Legal Immigrant in Michigan Sends a Message to MI Gov Whitmer and Media Criticizing Freedom-Loving Protesters, was first published on 100PercentFedUp.com.

The media and even some governors are trying to paint the Americans who are protesting to open businesses up as racists and even Nazis. The Governor of Michigan recently made a derogatory statement about the protesters implying they are racists. Painting a negative picture of the people who want their freedom and businesses demonizes our […]

Continue reading: Legal Immigrant in Michigan Sends a Message to MI Gov Whitmer and Media Criticizing Freedom-Loving Protesters ...

The following article, Breaking: Texas AG Calls for Immediate Release of Salon Owner Jailed for Opening…Texas Lt Gov Offers to Pay Salon Owner’s $7k Fine, was first published on 100PercentFedUp.com.

Salon A La Mode owner Shelley Luther opened her salon in defiance of the lockdown order for salons to stay closed during the coronavirus crisis. She boldly ripped. up the citation she was given by the police and refused to shut her doors. Luther hired a lawyer and went to court where an activist judge […]

Continue reading: Breaking: Texas AG Calls for Immediate Release of Salon Owner Jailed for Opening…Texas Lt Gov Offers to Pay Salon Owner’s $7k Fine ...

The following article, Dem Congresswoman: Biden Allegation ‘Put To Rest’ Because He ‘Went on TV’ And Denied It, was first published on 100PercentFedUp.com.

Democrat Rep. Dina Titus says that the allegations against 2020 Democrat presidential candidate Joe Biden are “put to rest” because he “went on TV” and denied them. Rep. Titus spoke with MSNBC’s Ayman Mohyeldin today about how she believes Biden because he flatly said he didn’t do it and didn’t say he doesn’t remember. It’s […]

Continue reading: Dem Congresswoman: Biden Allegation ‘Put To Rest’ Because He ‘Went on TV’ And Denied It ...

The following article, Chicago Inmate Switches Identities While Wearing Mask…Is Released from Jail, was first published on 100PercentFedUp.com.

A Cook County, Chicago inmate, was able to switch identities with another inmate allowing the wrong inmate to be released. How did they carry that off without anyone catching them? The inmate was wearing a mask when he was released, so it wasn’t as easy to identify him. Last Saturday, Quintin Henderson (pictured below), 28, […]

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The following article, MSNBC’s Brian Williams Chuckles With Dem Strategist as He Gloats, Mocks Trump About Tragic Downturn in Economy: “They were going to lose before this hit. They’re just going to lose worse now”, was first published on 100PercentFedUp.com.

James Carville spoke out before the coronavirus crisis to say that there is no way  Joe Biden has a chance at beating President Trump in the 2020 election. Well, He’s singing a different tune now at the expense of Americans suffering through this horrible pandemic and economic crisis. James Carvill is a Democratic strategist who […]

Continue reading: MSNBC’s Brian Williams Chuckles With Dem Strategist as He Gloats, Mocks Trump About Tragic Downturn in Economy: “They were going to lose before this hit. They’re just going to lose worse now” ...

The following article, Texas Gov Abbott Frees Salon Owner Shelley Luther: “Criminals shouldn’t be released to prevent COVID-19 just to put business owners in their place”, was first published on 100PercentFedUp.com.

Texas Governor Greg Abbott just changed the coronavirus order to free Salon A La Mode owner Shelley Luther from jail. Abbott tweeted out a comment about the poor treatment of the business owner: Throwing Texans in jail whose biz’s shut down through no fault of their own is wrong. I am eliminating jail for violating […]

Continue reading: Texas Gov Abbott Frees Salon Owner Shelley Luther: “Criminals shouldn’t be released to prevent COVID-19 just to put business owners in their place” ...

The following article, Video Scrubbed of Obama-Biden Ambassador To China Praising Their Response to Coronavirus: “I take my hat off to China”, was first published on 100PercentFedUp.com.

During a recent interview on CNN, Obama-Biden ambassador to China (2014-2017) Max Baucus compared standing up to China on the coronavirus to “Hitler in the ’30s.” Baucus has proven himself to be sympathetic to China in recent interviews, where he puts down America and praises the Chinese. The MSNBC video via The Washington Free Beacon […]

Continue reading: Video Scrubbed of Obama-Biden Ambassador To China Praising Their Response to Coronavirus: “I take my hat off to China” ...

The following article, Breaking: Justice Department Dropping Michael Flynn Criminal Case, was first published on 100PercentFedUp.com.

Michael Flynn has finally been exonerated. The Associated Press is reporting exclusively that the Justice Department said it is dropping the criminal case against President Trump’s first national security adviser, Michael Flynn. In court documents being filed Thursday, the Justice Department said it is dropping the case “after a considered review of all the facts […]

Continue reading: Breaking: Justice Department Dropping Michael Flynn Criminal Case ...

The following article, Video: Salon Owner Shelley Luther Released from Jail After Obama-Loyalist Judge Sentenced Her to 7 Days, was first published on 100PercentFedUp.com.

Salon A La Mode owner Shelley Luther was just released from jail today. The Texas Supreme Court and Texas Governor Greg Abbott both called for her release today (see below). When Luther left jail she was greeted by supporters who yelled “Shelley’s Free!” She thanked all of the new friends she’s made during this difficult […]

Continue reading: Video: Salon Owner Shelley Luther Released from Jail After Obama-Loyalist Judge Sentenced Her to 7 Days ...

The following article, BREAKING: President Trump’s Fiery Interview On Fox & Friends…”These are dirty politicians and dirty cops…They put our nation in danger with other nations, including Russia” [VIDEO], was first published on 100PercentFedUp.com.

This morning during a nearly one hour interview with Fox & Friends, President Trump addressed the decision by the DOJ to drop the case against the innocent General Michael Flynn. Trump ripped into the “dirty politicians and dirty cops” who went after General Michael Flynn. President Trump called the players involved in the horrible plot […]

Continue reading: BREAKING: President Trump’s Fiery Interview On Fox & Friends…”These are dirty politicians and dirty cops…They put our nation in danger with other nations, including Russia” [VIDEO] ...

The following article, Fed Judge Releases 21-Yr-Old Man To “Clean and Sober House” After Appearing In Court For Sexually Assaulting 12-Yr-Old Girl For One Month While Hiding In Her Bedroom, was first published on 100PercentFedUp.com.

The normalizing of pedophilia is not a far-right conspiracy theory...

Continue reading: Fed Judge Releases 21-Yr-Old Man To “Clean and Sober House” After Appearing In Court For Sexually Assaulting 12-Yr-Old Girl For One Month While Hiding In Her Bedroom ...

The following article, Greg Gutfeld Levels Ilhan Omar With Epic Response To Her Claim That “White Privilege” Is Reason Charges Were Dropped Against General Flynn, was first published on 100PercentFedUp.com.

Yesterday, after 3 1/2 years of having his character and integrity called into question, President Trump's first NSA, General Michael Flynn was finally...

Continue reading: Greg Gutfeld Levels Ilhan Omar With Epic Response To Her Claim That “White Privilege” Is Reason Charges Were Dropped Against General Flynn ...

The following article, BREAKING: Vice President Mike Pence’s Press Sec Katie Miller, Wife of President Trump’s Sr. Advisor, Stephen Miller, Tests Positive For COVID-19, was first published on 100PercentFedUp.com.

Only moments ago, White House Press Secretary Kayleigh McEnany confirmed that a member of Vice President Mike Pence’s team tested positive for coronavirus. Watch: White House Press Secretary Kayleigh McEnany confirms a member of Vice President Mike Pence's team tested positive for coronavirus pic.twitter.com/3VaUXbwMq7 — Bloomberg QuickTake (@QuickTake) May 8, 2020 Reuters White House Correspondent […]

Continue reading: BREAKING: Vice President Mike Pence’s Press Sec Katie Miller, Wife of President Trump’s Sr. Advisor, Stephen Miller, Tests Positive For COVID-19 ...

The following article, Video: Dallas Salon Owner Shelley Luther Gets Surprise Visit from Sen Ted Cruz for a Celebratory Haircut, was first published on 100PercentFedUp.com.

When Dallas, Texas salon owner Shelley Luther opened her salon in defiance of the lockdown order in Texas, she was visited numerous times by the local police and then sentenced to 7 days in jail with a fine of $7,000. After public outrage at her punishment, the Texas Supreme Court stepped in to demand her […]

Continue reading: Video: Dallas Salon Owner Shelley Luther Gets Surprise Visit from Sen Ted Cruz for a Celebratory Haircut ...

The following article, Obama Private Call Released: Implores Political Operatives to Help Protect Him…”We gotta make this happen”, was first published on 100PercentFedUp.com.

Michael Isikoff at Yahoo News on Friday night released audio of a call from former President Barack Obama to political operatives and the media to help protect “the rule of law” by protecting him. Obama desperately wants the Deep State and media to protect him by helping elect Joe Biden: “The fact that there is […]

Continue reading: Obama Private Call Released: Implores Political Operatives to Help Protect Him…”We gotta make this happen” ...

In Lakeshore, it may be a little while longer before a retail cannabis store opens.

The Fiat-Chrysler Windsor Assembly Plant looks to be on track for a May 19 reopening according to union leadership.

Essex County OPP have released a composite drawing of a suspect reported to be impersonating a police officer in Lakeshore.

Ontario’s provincial parks and conservation areas will reopen this week but campgrounds and beaches will continue to be off-limits for now.

One more person has died from the coronavirus in the Windsor-Essex region on Saturday and nine new cases have been reported by the health unit.

Brandon police officers are searching for a man who was caught on camera attempting to pump gas in his car – without prepaying.

Any plans to visit the Narcisse Snake Dens this Mother's Day weekend will have to be put on hold, after the province announced they are closed until further notice.

15 March 2020

Previous studies have shown that sphingosine kinase interacting protein (SKIP) inhibits sphingosine kinase (SK) function in fibroblasts. SK phosphorylates sphingosine producing the potent signaling molecule sphingosine-1-phosphate (S1P). SKIP gene (SPHKAP) expression is silenced by hypermethylation of its promoter in acute myeloid leukemia (AML). However, why SKIP activity is silenced in primary AML cells is unclear. Here, we investigated the consequences of SKIP down-regulation in AML primary cells and the effects of SKIP re-expression in leukemic cell lines. Using targeted ultra-HPLC-tandem MS (UPLC-MS/MS), we measured sphingolipids (including S1P and ceramides) in AML and control cells. Primary AML cells had significantly lower SK activity and intracellular S1P concentrations than control cells, and SKIP-transfected leukemia cell lines exhibited increased SK activity. These findings show that SKIP re-expression enhances SK activity in leukemia cells. Furthermore, other bioactive sphingolipids such as ceramide were also down-regulated in primary AML cells. Of note, SKIP re-expression in leukemia cells increased ceramide levels 2-fold, inactivated the key signaling protein extracellular signal-regulated kinase, and increased apoptosis following serum deprivation or chemotherapy. These results indicate that SKIP down-regulation in AML reduces SK activity and ceramide levels, an effect that ultimately inhibits apoptosis in leukemia cells. The findings of our study contrast with previous results indicating that SKIP inhibits SK function in fibroblasts and therefore challenge the notion that SKIP always inhibits SK activity.

The transcription factor forkhead box P3 (FOXP3) is a biomarker for regulatory T cells and can also be expressed in cancer cells, but its function in cancer appears to be divergent. The role of hepatocyte-expressed FOXP3 in hepatocellular carcinoma (HCC) is unknown. Here, we collected tumor samples and clinical information from 115 HCC patients and used five human cancer cell lines. We examined FOXP3 mRNA sequences for mutations, used a luciferase assay to assess promoter activities of FOXP3's target genes, and employed mouse tumor models to confirm in vitro results. We detected mutations in the FKH domain of FOXP3 mRNAs in 33% of the HCC tumor tissues, but in none of the adjacent nontumor tissues. None of the mutations occurred at high frequency, indicating that they occurred randomly. Notably, the mutations were not detected in the corresponding regions of FOXP3 genomic DNA, and many of them resulted in amino acid substitutions in the FKH region, altering FOXP3's subcellular localization. FOXP3 delocalization from the nucleus to the cytoplasm caused loss of transcriptional regulation of its target genes, inactivated its tumor-inhibitory capability, and changed cellular responses to histone deacetylase (HDAC) inhibitors. More complex FKH mutations appeared to be associated with worse prognosis in HCC patients. We conclude that mutations in the FKH domain of FOXP3 mRNA frequently occur in HCC and that these mutations are caused by errors in transcription and are not derived from genomic DNA mutations. Our results suggest that transcriptional mutagenesis of FOXP3 plays a role in HCC.

Prostate cancer (PCa) cells heavily rely on an active androgen receptor (AR) pathway for their survival. Enzalutamide (MDV3100) is a second-generation antiandrogenic drug that was approved by the Food and Drug Administration in 2012 to treat patients with castration-resistant prostate cancer (CRPC). However, emergence of resistance against this drug is inevitable, and it has been a major challenge to develop interventions that help manage enzalutamide-resistant CRPC. Erythropoietin-producing human hepatocellular (Eph) receptors are targeted by ephrin protein ligands and have a broad range of functions. Increasing evidence indicates that this signaling pathway plays an important role in tumorigenesis. Overexpression of EPH receptor B4 (EPHB4) has been observed in multiple types of cancer, being closely associated with proliferation, invasion, and metastasis of tumors. Here, using RNA-Seq analyses of clinical and preclinical samples, along with several biochemical and molecular methods, we report that enzalutamide-resistant PCa requires an active EPHB4 pathway that supports drug resistance of this tumor type. Using a small kinase inhibitor and RNAi-based gene silencing to disrupt EPHB4 activity, we found that these disruptions re-sensitize enzalutamide-resistant PCa to the drug both in vitro and in vivo. Mechanistically, we found that EPHB4 stimulates the AR by inducing proto-oncogene c-Myc (c-Myc) expression. Taken together, these results provide critical insight into the mechanism of enzalutamide resistance in PCa, potentially offering a therapeutic avenue for enhancing the efficacy of enzalutamide to better manage this common malignancy.

Heterotrimeric G proteins are the core upstream elements that transduce and amplify the cellular signals from G protein–coupled receptors (GPCRs) to intracellular effectors. GPCRs are the largest family of membrane proteins encoded in the human genome and are the targets of about one-third of prescription medicines. However, to date, no single therapeutic agent exerts its effects via perturbing heterotrimeric G protein function, despite a plethora of evidence linking G protein malfunction to human disease. Several recent studies have brought to light that the Gq family–specific inhibitor FR900359 (FR) is unexpectedly efficacious in silencing the signaling of Gq oncoproteins, mutant Gq variants that mostly exist in the active state. These data not only raise the hope that researchers working in drug discovery may be able to potentially strike Gq oncoproteins from the list of undruggable targets, but also raise questions as to how FR achieves its therapeutic effect. Here, we place emphasis on these recent studies and explain why they expand our pharmacological armamentarium for targeting Gq protein oncogenes as well as broaden our mechanistic understanding of Gq protein oncogene function. We also highlight how this novel insight impacts the significance and utility of using G(q) proteins as targets in drug discovery efforts.

The Mycobacterium tuberculosis virulence factor EsxA and its chaperone EsxB are secreted as a heterodimer (EsxA:B) and are crucial for mycobacterial escape from phagosomes and cytosolic translocation. Current findings support the idea that for EsxA to interact with host membranes, EsxA must dissociate from EsxB at low pH. However, the molecular mechanism by which the EsxA:B heterodimer separates is not clear. In the present study, using liposome-leakage and cytotoxicity assays, LC-MS/MS–based proteomics, and CCF-4 FRET analysis, we obtained evidence that the Nα-acetylation of the Thr-2 residue on EsxA, a post-translational modification that is present in mycobacteria but absent in Escherichia coli, is required for the EsxA:B separation. Substitutions at Thr-2 that precluded Nα-acetylation inhibited the heterodimer separation and hence prevented EsxA from interacting with the host membrane, resulting in attenuated mycobacterial cytosolic translocation and virulence. Molecular dynamics simulations revealed that at low pH, the Nα-acetylated Thr-2 makes direct and frequent “bind-and-release” contacts with EsxB, which generates a force that pulls EsxB away from EsxA. In summary, our findings provide evidence that the Nα-acetylation at Thr-2 of EsxA facilitates dissociation of the EsxA:B heterodimer required for EsxA membrane permeabilization and mycobacterial cytosolic translocation and virulence.

Type 2 diabetes mellitus (T2DM) is characterized by impaired glucose-stimulated insulin secretion and increased peripheral insulin resistance. Unremitting endoplasmic reticulum (ER) stress can lead to beta-cell apoptosis and has been linked to type 2 diabetes. Although many studies have attempted to link ER stress and T2DM, the specific effects of ER stress on beta-cell function remain incompletely understood. To determine the interrelationship between ER stress and beta-cell function, here we treated insulin-secreting INS-1(832/13) cells or isolated mouse islets with the ER stress–inducer tunicamycin (TM). TM induced ER stress as expected, as evidenced by activation of the unfolded protein response. Beta cells treated with TM also exhibited concomitant alterations in their electrical activity and cytosolic free Ca2+ oscillations. As ER stress is known to reduce ER Ca2+ levels, we tested the hypothesis that the observed increase in Ca2+ oscillations occurred because of reduced ER Ca2+ levels and, in turn, increased store-operated Ca2+ entry. TM-induced cytosolic Ca2+ and membrane electrical oscillations were acutely inhibited by YM58483, which blocks store-operated Ca2+ channels. Significantly, TM-treated cells secreted increased insulin under conditions normally associated with only minimal release, e.g. 5 mm glucose, and YM58483 blocked this secretion. Taken together, these results support a critical role for ER Ca2+ depletion–activated Ca2+ current in mediating Ca2+-induced insulin secretion in response to ER stress.

The protein-tyrosine phosphatase SHP2 is an allosteric enzyme critical for cellular events downstream of growth factor receptors. Mutations in the SHP2 gene have been linked to many different types of human diseases, including developmental disorders, leukemia, and solid tumors. Unlike most SHP2-activating mutations, the T507K substitution in SHP2 is unique in that it exhibits oncogenic Ras-like transforming activity. However, the biochemical basis of how the SHP2/T507K variant elicits transformation remains unclear. By combining kinetic and biophysical methods, X-ray crystallography, and molecular modeling, as well as using cell biology approaches, here we uncovered that the T507K substitution alters both SHP2 substrate specificity and its allosteric regulatory mechanism. We found that although SHP2/T507K exists in the closed, autoinhibited conformation similar to the WT enzyme, the interactions between its N-SH2 and protein-tyrosine phosphatase domains are weakened such that SHP2/T507K possesses a higher affinity for the scaffolding protein Grb2-associated binding protein 1 (Gab1). We also discovered that the T507K substitution alters the structure of the SHP2 active site, resulting in a change in SHP2 substrate preference for Sprouty1, a known negative regulator of Ras signaling and a potential tumor suppressor. Our results suggest that SHP2/T507K's shift in substrate specificity coupled with its preferential association of SHP2/T507K with Gab1 enable the mutant SHP2 to more efficiently dephosphorylate Sprouty1 at pTyr-53. This dephosphorylation hyperactivates Ras signaling, which is likely responsible for SHP2/T507K's Ras-like transforming activity.

Bacterial type VII secretion systems secrete a wide range of extracellular proteins that play important roles in bacterial viability and in interactions of pathogenic mycobacteria with their hosts. Mycobacterial type VII secretion systems consist of five subtypes, ESX-1–5, and have four substrate classes, namely, Esx, PE, PPE, and Esp proteins. At least some of these substrates are secreted as heterodimers. Each ESX system mediates the secretion of a specific set of Esx, PE, and PPE proteins, raising the question of how these substrates are recognized in a system-specific fashion. For the PE/PPE heterodimers, it has been shown that they interact with their cognate EspG chaperone and that this chaperone determines the designated secretion pathway. However, both structural and pulldown analyses have suggested that EspG cannot interact with the Esx proteins. Therefore, the determining factor for system specificity of the Esx proteins remains unknown. Here, we investigated the secretion specificity of the ESX-1 substrate pair EsxB_1/EsxA_1 in Mycobacterium marinum. Although this substrate pair was hardly secreted when homologously expressed, it was secreted when co-expressed together with the PE35/PPE68_1 pair, indicating that this pair could stimulate secretion of the EsxB_1/EsxA_1 pair. Surprisingly, co-expression of EsxB_1/EsxA_1 with a modified PE35/PPE68_1 version that carried the EspG5 chaperone-binding domain, previously shown to redirect this substrate pair to the ESX-5 system, also resulted in redirection and co-secretion of the Esx pair via ESX-5. Our results suggest a secretion model in which PE35/PPE68_1 determines the system-specific secretion of EsxB_1/EsxA_1.

The rapid emergence and dissemination of methicillin-resistant Staphylococcus aureus (MRSA) strains poses a major threat to public health. MRSA possesses an arsenal of secreted host-damaging virulence factors that mediate pathogenicity and blunt immune defenses. Panton–Valentine leukocidin (PVL) and α-toxin are exotoxins that create lytic pores in the host cell membrane. They are recognized as being important for the development of invasive MRSA infections and are thus potential targets for antivirulence therapies. Here, we report the high-resolution X-ray crystal structures of both PVL and α-toxin in their soluble, monomeric, and oligomeric membrane-inserted pore states in complex with n-tetradecylphosphocholine (C14PC). The structures revealed two evolutionarily conserved phosphatidylcholine-binding mechanisms and their roles in modulating host cell attachment, oligomer assembly, and membrane perforation. Moreover, we demonstrate that the soluble C14PC compound protects primary human immune cells in vitro against cytolysis by PVL and α-toxin and hence may serve as the basis for the development of an antivirulence agent for managing MRSA infections.

Tau is a microtubule-associated protein that plays a major role in Alzheimer's disease (AD) and other tauopathies. Recent reports indicate that, in the presence of crowding agents, tau can undergo liquid–liquid phase separation (LLPS), forming highly dynamic liquid droplets. Here, using recombinantly expressed proteins, turbidimetry, fluorescence microscopy imaging, and fluorescence recovery after photobleaching (FRAP) assays, we show that the divalent transition metal zinc strongly promotes this process, shifting the equilibrium phase boundary to lower protein or crowding agent concentrations. We observed no tau LLPS-promoting effect for any other divalent transition metal ions tested, including Mn2+, Fe2+, Co2+, Ni2+, and Cu2+. We also demonstrate that multiple zinc-binding sites on tau are involved in the LLPS-promoting effect and provide insights into the mechanism of this process. Zinc concentration is highly elevated in AD brains, and this metal ion is believed to be an important player in the pathogenesis of this disease. Thus, the present findings bring a new dimension to understanding the relationship between zinc homeostasis and the pathogenic process in AD and related neurodegenerative disorders.

Assembled α-synuclein in nerve cells and glial cells is the defining pathological feature of neurodegenerative diseases called synucleinopathies. Seeds of α-synuclein can induce the assembly of monomeric protein. Here, we used sucrose gradient centrifugation and transiently transfected HEK 293T cells to identify the species of α-synuclein from the brains of homozygous, symptomatic mice transgenic for human mutant A53T α-synuclein (line M83) that seed aggregation. The most potent fractions contained Sarkosyl-insoluble assemblies enriched in filaments. We also analyzed six cases of idiopathic Parkinson's disease (PD), one case of familial PD, and six cases of multiple system atrophy (MSA) for their ability to induce α-synuclein aggregation. The MSA samples were more potent than those of idiopathic PD in seeding aggregation. We found that following sucrose gradient centrifugation, the most seed-competent fractions from PD and MSA brains are those that contain Sarkosyl-insoluble α-synuclein. The fractions differed between PD and MSA, consistent with the presence of distinct conformers of assembled α-synuclein in these different samples. We conclude that α-synuclein filaments are the main driving force for amplification and propagation of pathology in synucleinopathies.

Cone photoreceptors in the retina enable vision over a wide range of light intensities. However, the processes enabling cone vision in bright light (i.e. photopic vision) are not adequately understood. Chromophore regeneration of cone photopigments may require the retinal pigment epithelium (RPE) and/or retinal Müller glia. In the RPE, isomerization of all-trans-retinyl esters to 11-cis-retinol is mediated by the retinoid isomerohydrolase Rpe65. A putative alternative retinoid isomerase, dihydroceramide desaturase-1 (DES1), is expressed in RPE and Müller cells. The retinol-isomerase activities of Rpe65 and Des1 are inhibited by emixustat and fenretinide, respectively. Here, we tested the effects of these visual cycle inhibitors on immediate, early, and late phases of cone photopic vision. In zebrafish larvae raised under cyclic light conditions, fenretinide impaired late cone photopic vision, while the emixustat-treated zebrafish unexpectedly had normal vision. In contrast, emixustat-treated larvae raised under extensive dark-adaptation displayed significantly attenuated immediate photopic vision concomitant with significantly reduced 11-cis-retinaldehyde (11cRAL). Following 30 min of light, early photopic vision was recovered, despite 11cRAL levels remaining significantly reduced. Defects in immediate cone photopic vision were rescued in emixustat- or fenretinide-treated larvae following exogenous 9-cis-retinaldehyde supplementation. Genetic knockout of Des1 (degs1) or retinaldehyde-binding protein 1b (rlbp1b) did not eliminate photopic vision in zebrafish. Our findings define molecular and temporal requirements of the nonphotopic or photopic visual cycles for mediating vision in bright light.

Interferon-regulated myxovirus resistance protein B (MxB) is an interferon-induced GTPase belonging to the dynamin superfamily. It inhibits infection with a wide range of different viruses, including HIV-1, by impairing viral DNA entry into the nucleus. Unlike the related antiviral GTPase MxA, MxB possesses an N-terminal region that contains a nuclear localization signal and is crucial for inhibiting HIV-1. Because MxB previously has been shown to reside in both the nuclear envelope and the cytoplasm, here we used bioinformatics and biochemical approaches to identify a nuclear export signal (NES) responsible for MxB's cytoplasmic location. Using the online computational tool LocNES (Locating Nuclear Export Signals or NESs), we identified five putative NES candidates in MxB and investigated whether their deletion caused nuclear localization of MxB. Our results revealed that none of the five deletion variants relocates to the nucleus, suggesting that these five predicted NES sequences do not confer NES activity. Interestingly, deletion of one sequence, encompassing amino acids 505–527, abrogated the anti-HIV-1 activity of MxB. Further mutation experiments disclosed that amino acids 515–519, and Pro-515 in particular, regulate MxB oligomerization and its binding to HIV-1 capsid, thereby playing an important role in MxB-mediated restriction of HIV-1 infection. In summary, our results indicate that none of the five predicted NES sequences in MxB appears to be required for its nuclear export. Our findings also reveal several residues in MxB, including Pro-515, critical for its oligomerization and anti-HIV-1 function.

Carbon monoxide (CO) remains the most common cause of human poisoning. The consequences of CO poisoning include cardiac dysfunction, brain injury, and death. CO causes toxicity by binding to hemoglobin and by inhibiting mitochondrial cytochrome c oxidase (CcO), thereby decreasing oxygen delivery and inhibiting oxidative phosphorylation. We have recently developed a CO antidote based on human neuroglobin (Ngb-H64Q-CCC). This molecule enhances clearance of CO from red blood cells in vitro and in vivo. Herein, we tested whether Ngb-H64Q-CCC can also scavenge CO from CcO and attenuate CO-induced inhibition of mitochondrial respiration. Heart tissue from mice exposed to 3% CO exhibited a 42 ± 19% reduction in tissue respiration rate and a 33 ± 38% reduction in CcO activity compared with unexposed mice. Intravenous infusion of Ngb-H64Q-CCC restored respiration rates to that of control mice correlating with higher electron transport chain CcO activity in Ngb-H64Q-CCC–treated compared with PBS-treated, CO-poisoned mice. Further, using a Clark-type oxygen electrode, we measured isolated rat liver mitochondrial respiration in the presence and absence of saturating solutions of CO (160 μm) and nitric oxide (100 μm). Both CO and NO inhibited respiration, and treatment with Ngb-H64Q-CCC (100 and 50 μm, respectively) significantly reversed this inhibition. These results suggest that Ngb-H64Q-CCC mitigates CO toxicity by scavenging CO from carboxyhemoglobin, improving systemic oxygen delivery and reversing the inhibitory effects of CO on mitochondria. We conclude that Ngb-H64Q-CCC or other CO scavengers demonstrate potential as antidotes that reverse the clinical and molecular effects of CO poisoning.

The plasmas of diabetic or uremic patients and of those receiving peritoneal dialysis treatment have increased levels of the glucose-derived dicarbonyl metabolites like methylglyoxal (MGO), glyoxal (GO), and 3-deoxyglucosone (3-DG). The elevated dicarbonyl levels can contribute to the development of painful neuropathies. Here, we used stimulated immunoreactive Calcitonin Gene–Related Peptide (iCGRP) release as a measure of nociceptor activation, and we found that each dicarbonyl metabolite induces a concentration-, TRPA1-, and Ca2+-dependent iCGRP release. MGO, GO, and 3-DG were about equally potent in the millimolar range. We hypothesized that another dicarbonyl, 3,4-dideoxyglucosone-3-ene (3,4-DGE), which is present in peritoneal dialysis (PD) solutions after heat sterilization, activates nociceptors. We also showed that at body temperatures 3,4-DGE is formed from 3-DG and that concentrations of 3,4-DGE in the micromolar range effectively induced iCGRP release from isolated murine skin. In a novel preparation of the isolated parietal peritoneum PD fluid or 3,4-DGE alone, at concentrations found in PD solutions, stimulated iCGRP release. We also tested whether inflammatory tissue conditions synergize with dicarbonyls to induce iCGRP release from isolated skin. Application of MGO together with bradykinin or prostaglandin E2 resulted in an overadditive effect on iCGRP release, whereas MGO applied at a pH of 5.2 resulted in reduced release, probably due to an MGO-mediated inhibition of transient receptor potential (TRP) V1 receptors. These results indicate that several reactive dicarbonyls activate nociceptors and potentiate inflammatory mediators. Our findings underline the roles of dicarbonyls and TRPA1 receptors in causing pain during diabetes or renal disease.

Manganese (Mn) is an essential micronutrient required for the normal development of many organs, including the brain. Although its roles as a cofactor in several enzymes and in maintaining optimal physiology are well-known, the overall biological functions of Mn are rather poorly understood. Alterations in body Mn status are associated with altered neuronal physiology and cognition in humans, and either overexposure or (more rarely) insufficiency can cause neurological dysfunction. The resultant balancing act can be viewed as a hormetic U-shaped relationship for biological Mn status and optimal brain health, with changes in the brain leading to physiological effects throughout the body and vice versa. This review discusses Mn homeostasis, biomarkers, molecular mechanisms of cellular transport, and neuropathological changes associated with disruptions of Mn homeostasis, especially in its excess, and identifies gaps in our understanding of the molecular and biochemical mechanisms underlying Mn homeostasis and neurotoxicity.

Treatment of patients with triple-negative breast cancer (TNBC) is limited by a lack of effective molecular therapies targeting this disease. Recent studies have identified metabolic alterations in cancer cells that can be targeted to improve responses to standard-of-care chemotherapy regimens. Using MDA-MB-468 and SUM-159PT TNBC cells, along with LC-MS/MS and HPLC metabolomics profiling, we found here that exposure of TNBC cells to the cytotoxic chemotherapy drugs cisplatin and doxorubicin alter arginine and polyamine metabolites. This alteration was because of a reduction in the levels and activity of a rate-limiting polyamine biosynthetic enzyme, ornithine decarboxylase (ODC). Using gene silencing and inhibitor treatments, we determined that the reduction in ODC was mediated by its negative regulator antizyme, targeting ODC to the proteasome for degradation. Treatment with the ODC inhibitor difluoromethylornithine (DFMO) sensitized TNBC cells to chemotherapy, but this was not observed in receptor-positive breast cancer cells. Moreover, TNBC cell lines had greater sensitivity to single-agent DFMO, and ODC levels were elevated in TNBC patient samples. The alterations in polyamine metabolism in response to chemotherapy, as well as DFMO-induced preferential sensitization of TNBC cells to chemotherapy, reported here suggest that ODC may be a targetable metabolic vulnerability in TNBC.

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