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Oversight panel to subpoena Sheriff Alex Villanueva for testimony on coronavirus in jails

The Sheriff Civilian Oversight Commission voted Thursday to subpoena L.A. County Sheriff Alex Villanueva for testimony regarding the coronavirus outbreak in the jails.




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Lippi resigns as Italy head coach

Marcello Lippi resigns as Italy coach after leading the nation to World Cup glory.




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Sunderland sign Kyrgiakos on loan

Sunderland complete the signing of defender Sotirios Kyrgiakos on loan from VfL Wolfsburg until the end of the season.




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West Ham sign Man Utd's Morrison

West Ham United sign Manchester United's Ravel Morrison for an undisclosed fee.




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Everton sign Jelavic from Rangers

Everton sign Croatian international striker Nikica Jelavic from Rangers.




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Man City sign Pizarro from Roma

Chilean midfielder David Pizarro joins Manchester City on loan from Roma for the rest of the season.




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Australians urged to sign up to tracking app

PM Scott Morrison said wide usage would be the "ticket" to normal life resuming as soon as possible.




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St. Thomas, Ont. judge does away with signature requirement due to COVID-19 fears

An Ontario judge has dispensed with the need for a signature on a probation order due to the risks of COVID-19.




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Trump Signature Camper Mug

We here at Patriot Depot have mastered the art of creating the perfect cup o' joe: no cream, no sugar, and one Donald. (You can alter the first two according to taste.)

You will brew the perfect cup of coffee with..

Price: $14.95





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‘Eliza’ game review: An insightful visual novel with a vision for self-care’s future




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How ‘Frozen II’s’ new creatures are enchanting marvels of design

From the adorable to the powerful, here's what the sequel delivers that's new, and eye-popping, to fans.




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‘Resident Evil 3’: Great graphics and good level design, but it’s still the zombie apocalypse

The true star of “Resident Evil 3” is its supurb graphics engine.




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A new autonomous delivery vehicle is designed to operate like a bicycle

In Ann Arbor, Mich., the creators of a new autonomous vehicle have designed their robot to operate on local streets — but more so like a bicycle than a car.




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Trade was supposed to be Trump’s signature issue. His efforts have fallen flat.

Whatever meager gains Trump’s trade deals represent hardly look worth the pain we endured getting here.




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From Concept to Design: How Developers Create Today’s Most Popular Mobile Games

In the past five years, mobile games have exploded in popularity. With the advent of Apple’s App Store, mobile app developers have jumped on the opportunity to create mobile games from scratch on the most popular devices in the world. What Makes a Mobile Game Go Viral? Why is it that some mobile games become […]

The post From Concept to Design: How Developers Create Today’s Most Popular Mobile Games appeared first on SpyreStudios.




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12 Yoga Website Designs for Inspiration

Staying fit these days is now more important than ever with the global pandemic having no cure or vaccine yet other than a healthy body. It just so happens that being active is also more difficult because gyms are closed in affected areas. Home workouts like yoga, in that regard, are golden and yoga website […]

The post 12 Yoga Website Designs for Inspiration appeared first on SpyreStudios.




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12 Home Office Setup Ideas for Web Designers and Developers

Coffee, music, YouTube channels, and procrastination— only a handful of things can make your day when it comes to increasing productivity but none of them are as complete as having a home office setup. It makes a world of difference where and how you work especially if you work from home. Hence, some home office […]

The post 12 Home Office Setup Ideas for Web Designers and Developers appeared first on SpyreStudios.




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How to Use Instagram To Grow Your Web Design Business

One of the biggest mistakes a business owner can make today is ignoring social media marketing or treating it as an afterthought. This is even more so in an increasingly competitive space like the web design niche where small businesses have to strive to leave the shadows of more established brands with years of history […]

The post How to Use Instagram To Grow Your Web Design Business appeared first on SpyreStudios.




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Roundup: Web Design Articles May 8, 2020

With the lockdown across nations, you are probably spending more time reading. Whether it’s for pleasure or for work, we’re here to help you fill your time with some reading material. These web design articles are not only about best practices, deals, and trends in the niche but also include feel-good stories that we all […]

The post Roundup: Web Design Articles May 8, 2020 appeared first on SpyreStudios.




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oscon: Mobile UX Design & Development for Apps - learn to craft an app that’s functional and fun to use http://t.co/L8kTLaxbYH #oscon #tutorial

oscon: Mobile UX Design & Development for Apps - learn to craft an app that’s functional and fun to use http://t.co/L8kTLaxbYH #oscon #tutorial




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How to Ensure Your Data is Providing Trustworthy Insights

For building owners and managers, data is the fuel behind their smart building operations. Leveraging the surplus of data that is readily available to them, owners and managers are making informed decisions for their facility that can create long-term performance enhancements and help them achieve goals such as improved efficiency and occupant comfort. Here is […]

The post How to Ensure Your Data is Providing Trustworthy Insights appeared first on ReadWrite.





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Advertisers signal glimmers of optimism, start spending again

Despite numerous unknowns and continued challenges, many agencies and advertisers say they have shifted gears for the next phase.

Please visit Search Engine Land for the full article.




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News24.com | Coronavirus: the power of hindsight

In the past three days we have averaged 354 deaths here in Italy. We've run out of doctors, nurses and hospitals to help those infected. South Africa has the power of hindsight. Start to take action now.




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Scientist Behind Social Distancing Breaks Own Rules To Cheat with Married Woman, Resigns

The health expert who helped shaped Britain’s lockdown policies in response to the coronavirus has resigned after admitting he broke his own rules by having his married lover visit him at his home. Professor Neil Ferguson, 51, of Imperial College in London was a prominent member of the Scientific Advisory Group for Emergencies. The Telegraph…

The post Scientist Behind Social Distancing Breaks Own Rules To Cheat with Married Woman, Resigns appeared first on The Western Journal.




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Man Posts Hilarious ‘Bad Dad Jokes’ Daily on Sign in Front Lawn To Spread Cheer to Neighbors

When jokes are so horrible, so obvious, so corny that they make your eyes roll, it’s a good chance that they’re what many call “dad jokes.” Bordering on lame, and all the more hilarious because of it, these jokes are so bad and yet fathers seem to get such joy from trotting out the perfect…

The post Man Posts Hilarious ‘Bad Dad Jokes’ Daily on Sign in Front Lawn To Spread Cheer to Neighbors appeared first on The Western Journal.




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How to Design a Data Center in a Norwegian Fjord




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Signs of Slowing Unemployment; U.S. Jobless Claims Decline for Four Weeks in a Row

Signs of Slowing Unemployment

Although millions of people lost their jobs because of the coronavirus, a surge of companies is hiring additional employees due to increased demands.




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Signs of Slowing Unemployment; More Than Half of States Had Fewer Jobless Claims for Four Weeks in a Row

Signs of Slowing Unemployment

Following an unprecedented surge in jobless claims in March due to the coronavirus, unemployment is continuously slowing in April in 26 states.




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Sign up for the Sport Relief Mile

Part of the Sport Relief promo for the BBC UK Homepage




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Mechanistic insights explain the transforming potential of the T507K substitution in the protein-tyrosine phosphatase SHP2 [Signal Transduction]

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.




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NAD+ biosynthesis in bacteria is controlled by global carbon/nitrogen levels via PII signaling [Microbiology]

NAD+ is a central metabolite participating in core metabolic redox reactions. The prokaryotic NAD synthetase enzyme NadE catalyzes the last step of NAD+ biosynthesis, converting nicotinic acid adenine dinucleotide (NaAD) to NAD+. Some members of the NadE family use l-glutamine as a nitrogen donor and are named NadEGln. Previous gene neighborhood analysis has indicated that the bacterial nadE gene is frequently clustered with the gene encoding the regulatory signal transduction protein PII, suggesting a functional relationship between these proteins in response to the nutritional status and the carbon/nitrogen ratio of the bacterial cell. Here, using affinity chromatography, bioinformatics analyses, NAD synthetase activity, and biolayer interferometry assays, we show that PII and NadEGln physically interact in vitro, that this complex relieves NadEGln negative feedback inhibition by NAD+. This mechanism is conserved in distantly related bacteria. Of note, the PII protein allosteric effector and cellular nitrogen level indicator 2-oxoglutarate (2-OG) inhibited the formation of the PII-NadEGln complex within a physiological range. These results indicate an interplay between the levels of ATP, ADP, 2-OG, PII-sensed glutamine, and NAD+, representing a metabolic hub that may balance the levels of core nitrogen and carbon metabolites. Our findings support the notion that PII proteins act as a dissociable regulatory subunit of NadEGln, thereby enabling the control of NAD+ biosynthesis according to the nutritional status of the bacterial cell.




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Significant political change is coming to the Gulf

19 February 2015

20150212GCCKinninmont.jpg

Photo by ArabianEye / Getty Images

Significant political change is coming to the Gulf monarchies, often seen in the West as bastions of stability, argues a new Chatham House report entitled Future Trends in the Gulf.

The Gulf states are already undergoing dramatic demographic and economic changes – changes which are being accelerated by lower oil prices.

The current political systems in the Gulf have been defined by the oil era, enabling governments to provide extensive economic benefits and no taxation, while maintaining a monopoly over political power. As the economic role of the state changes, its political role will change too.

Even at a time of plenty, pressures for political change have been rising. Significant changes in the availability of information, the surge in social media and women’s education are driving new demands for transparency.

Political protests have been most visible in Bahrain, but calls for change and reform have been growing in all of the Gulf countries. Raif Badawi, the blogger recently flogged in Saudi Arabia, is hardly an isolated case: campaigners for constitutional monarchies and elected parliaments have been facing severe punishments for years. 

The report author, Jane Kinninmont, says:

'The US and UK underestimate the significant leverage that they still have in the Gulf compared with most other countries, even if it is less than in the 20th century. As much as Asian countries are strengthening their trade links with the Gulf, they are reluctant to step forward as the security allies that the Gulf countries need.' 

Combating instability, extremism and sectarianism in the wider region requires looking hard at the pressures for change and insecurities inside the Gulf states. These help explain, for instance, why Qatar and the UAE have backed different sides in the intensifying civil conflict in Egypt.

The report, based on three years of research, argues that:      

  • It is time for the GCC countries to seize the opportunity to carry out gradual and consensual political and social reforms towards more constitutional forms of monarchy. 

  • Western countries, especially the US and UK, need to diversify the base of relations with the Gulf beyond the existing elite – and reach out to a broader base among the increasingly well-educated and aspirational new generation.

  • Defence cooperation with the Gulf needs to be placed in a wider political context, where respect for human rights is not seen as being at odds with security imperatives, but as part of ensuring sustainable security. The UK and US policy of expanding their military bases in Bahrain has sent a strong signal that political reform is not their priority. 

  • A fresh discourse on Gulf security needs to take account of the need for people to feel secure vis-à-vis their own governments, for instance by ensuring the police are held accountable by independent judiciaries, and ending lengthy detention without trial.

  • In partnering with Gulf countries against extremism, Western allies need to broach sensitive issues such as religious education in Saudi Arabia, or the impact on Western publics and Muslim communities outside the region of flogging a blogger for insulting Islam.

Editor's notes

Read the report Future Trends in the Gulf by Jane Kinninmont, MENA Programme. Embargoed until Thursday 19 February, 00:01 GMT. Read the executive summary here

When linking to this report, please use this link, which will go live when the embargo is lifted. 

This report will be launched at an event at Chatham House on 19 February.          

For all enquiries, please contact the press office. 

To contact the author directly, please use:
Email:  jkinninmont@chathamhouse.org
Phone: +44 (0)7967 325 993
Twitter: @janekinninmont




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Legal Provision for Crisis Preparedness: Foresight not Hindsight

21 April 2020

Dr Patricia Lewis

Research Director, Conflict, Science & Transformation; Director, International Security Programme
COVID-19 is proving to be a grave threat to humanity. But this is not a one-off, there will be future crises, and we can be better prepared to mitigate them.

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Examining a patient while testing for COVID-19 at the Velocity Urgent Care in Woodbridge, Virginia. Photo by Chip Somodevilla/Getty Images.

A controversial debate during COVID-19 is the state of readiness within governments and health systems for a pandemic, with lines of the debate drawn on the issues of testing provision, personal protective equipment (PPE), and the speed of decision-making.

President Macron in a speech to the nation admitted French medical workers did not have enough PPE and that mistakes had been made: ‘Were we prepared for this crisis? We have to say that no, we weren’t, but we have to admit our errors … and we will learn from this’.

In reality few governments were fully prepared. In years to come, all will ask: ‘how could we have been better prepared, what did we do wrong, and what can we learn?’. But after every crisis, governments ask these same questions.

Most countries have put in place national risk assessments and established processes and systems to monitor and stress-test crisis-preparedness. So why have some countries been seemingly better prepared?

Comparing different approaches

Some have had more time and been able to watch the spread of the disease and learn from those countries that had it first. Others have taken their own routes, and there will be much to learn from comparing these different approaches in the longer run.

Governments in Asia have been strongly influenced by the experience of the SARS epidemic in 2002-3 and - South Korea in particular - the MERS-CoV outbreak in 2015 which was the largest outside the Middle East. Several carried out preparatory work in terms of risk assessment, preparedness measures and resilience planning for a wide range of threats.

Case Study of Preparedness: South Korea

By 2007, South Korea had established the Division of Public Health Crisis Response in Korea Centers for Disease Control and Prevention (KCDC) and, in 2016, the KCDC Center for Public Health Emergency Preparedness and Response had established a round-the-clock Emergency Operations Center with rapid response teams.

KCDC is responsible for the distribution of antiviral stockpiles to 16 cities and provinces that are required by law to hold and manage antiviral stockpiles.

And, at the international level, there are frameworks for preparedness for pandemics. The International Health Regulations (IHR) - adopted at the 2005 World Health Assembly and binding on member states - require countries to report certain disease outbreaks and public health events to the World Health Organization (WHO) and ‘prevent, protect against, control and provide a public health response to the international spread of disease in ways that are commensurate with and restricted to public health risks, and which avoid unnecessary interference with international traffic and trade’.

Under IHR, governments committed to a programme of building core capacities including coordination, surveillance, response and preparedness. The UN Sendai Framework for Disaster Risk highlights disaster preparedness for effective response as one of its main purposes and has already incorporated these measures into the Sustainable Development Goals (SDGs) and other Agenda 2030 initiatives. UN Secretary-General António Guterres has said COVID-19 ‘poses a significant threat to the maintenance of international peace and security’ and that ‘a signal of unity and resolve from the Council would count for a lot at this anxious time’.

Case Study of Preparedness: United States

The National Institutes of Health (NIH) and the Center for Disease Control (CDC) established PERRC – the Preparedness for Emergency Response Research Centers - as a requirement of the 2006 Pandemic and All-Hazards Preparedness Act, which required research to ‘improve federal, state, local, and tribal public health preparedness and response systems’.

The 2006 Act has since been supplanted by the 2019 Pandemic and All-Hazards Preparedness and Advancing Innovation Act. This created the post of Assistant Secretary for Preparedness and Response (ASPR) in the Department for Health and Human Services (HHS) and authorised the development and acquisitions of medical countermeasures and a quadrennial National Health Security Strategy.

The 2019 Act also set in place a number of measures including the requirement for the US government to re-evaluate several important metrics of the Public Health Emergency Preparedness cooperative agreement and the Hospital Preparedness Program, and a requirement for a report on the states of preparedness and response in US healthcare facilities.

This pandemic looks set to continue to be a grave threat to humanity. But there will also be future pandemics – whether another type of coronavirus or a new influenza virus – and our species will be threatened again, we just don’t know when.

Other disasters too will befall us – we already see the impacts of climate change arriving on our doorsteps characterised by increased numbers and intensity of floods, hurricanes, fires, crop failure and other manifestations of a warming, increasingly turbulent atmosphere and we will continue to suffer major volcanic eruptions, earthquakes and tsunamis. All high impact, unknown probability events.

Preparedness for an unknown future is expensive and requires a great deal of effort for events that may not happen within the preparers’ lifetimes. It is hard to imagine now, but people will forget this crisis, and revert to their imagined projections of the future where crises don’t occur, and progress follows progress. But history shows us otherwise.

Preparations for future crises always fall prey to financial cuts and austerity measures in lean times unless there is a mechanism to prevent that. Cost-benefit analyses will understandably tend to prioritise the urgent over the long-term. So governments should put in place legislation – or strengthen existing legislation – now to ensure their countries are as prepared as possible for whatever crisis is coming.

Such a legal requirement would require governments to report back to parliament every year on the state of their national preparations detailing such measures as:

  • The exact levels of stocks of essential materials (including medical equipment)
  • The ability of hospitals to cope with large influx of patients
  • How many drills, exercises and simulations had been organised – and their findings
  • What was being done to implement lessons learned & improve preparedness

In addition, further actions should be taken:

  • Parliamentary committees such as the UK Joint Committee on the National Security Strategy should scrutinise the government’s readiness for the potential threats outlined in the National Risk register for Civil Emergencies in-depth on an annual basis.
  • Parliamentarians, including ministers, with responsibility for national security and resilience should participate in drills, table-top exercises and simulations to see for themselves the problems inherent with dealing with crises.
  • All governments should have a minister (or equivalent) with the sole responsibility for national crisis preparedness and resilience. The Minister would be empowered to liaise internationally and coordinate local responses such as local resilience groups.
  • There should be ring-fenced budget lines in annual budgets specifically for preparedness and resilience measures, annually reported on and assessed by parliaments as part of the due diligence process.

And at the international level:

  • The UN Security Council should establish a Crisis Preparedness Committee to bolster the ability of United Nations Member States to respond to international crisis such as pandemics, within their borders and across regions. The Committee would function in a similar fashion as the Counter Terrorism Committee that was established following the 9/11 terrorist attacks in the United States.
  • States should present reports on their level of preparedness to the UN Security Council. The Crisis Preparedness Committee could establish a group of experts who would conduct expert assessments of each member state’s risks and preparedness and facilitate technical assistance as required.
  • Regional bodies such as the OSCE, ASEAN and ARF, the AU, the OAS, the PIF etc could also request national reports on crisis preparedness for discussion and cooperation at the regional level.

COVID-19 has been referred to as the 9/11 of crisis preparedness and response. Just as that shocking terrorist attack shifted the world and created a series of measures to address terrorism, we now recognise our security frameworks need far more emphasis on being prepared and being resilient. Whatever has been done in the past, it is clear that was nowhere near enough and that has to change.

Case Study of Preparedness: The UK

The National Risk Register was first published in 2008 as part of the undertakings laid out in the National Security Strategy (the UK also published the Biological Security Strategy in July 2018). Now entitled the National Risk Register for Civil Emergencies it has been updated regularly to analyse the risks of major emergencies that could affect the UK in the next five years and provide resilience advice and guidance.

The latest edition - produced in 2017 when the UK had a Minister for Government Resilience and Efficiency - placed the risk of a pandemic influenza in the ‘highly likely and most severe’ category. It stood out from all the other identified risks, whereas an emerging disease (such as COVID-19) was identified as ‘highly likely but with moderate impact’.

However, much preparatory work for an influenza pandemic is the same as for COVID-19, particularly in prepositioning large stocks of PPE, readiness within large hospitals, and the creation of new hospitals and facilities.

One key issue is that the 2017 NHS Operating Framework for Managing the Response to Pandemic Influenza was dependent on pre-positioned ’just in case’ stockpiles of PPE. But as it became clear the PPE stocks were not adequate for the pandemic, it was reported that recommendations about the stockpile by NERVTAG (the New and Emerging Respiratory Virus Threats Advisory Group which advises the government on the threat posed by new and emerging respiratory viruses) had been subjected to an ‘economic assessment’ and decisions reversed on, for example, eye protection.

The UK chief medical officer Dame Sally Davies, when speaking at the World Health Organization about Operation Cygnus – a 2016 three-day exercise on a flu pandemic in the UK – reportedly said the UK was not ready for a severe flu attack and ‘a lot of things need improving’.

Aware of the significance of the situation, the UK Parliamentary Joint Committee on the National Security Strategy launched an inquiry in 2019 on ‘Biosecurity and human health: preparing for emerging infectious diseases and bioweapons’ which intended to coordinate a cross-government approach to biosecurity threats. But the inquiry had to postpone its oral hearings scheduled for late October 2019 and, because of the general election in December 2019, the committee was obliged to close the inquiry.




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The mRNA levels of heat shock factor 1 are regulated by thermogenic signals via the cAMP-dependent transcription factor ATF3 [Metabolism]

Heat shock factor 1 (HSF1) regulates cellular adaptation to challenges such as heat shock and oxidative and proteotoxic stresses. We have recently reported a previously unappreciated role for HSF1 in the regulation of energy metabolism in fat tissues; however, whether HSF1 is differentially expressed in adipose depots and how its levels are regulated in fat tissues remain unclear. Here, we show that HSF1 levels are higher in brown and subcutaneous fat tissues than in those in the visceral depot and that HSF1 is more abundant in differentiated, thermogenic adipocytes. Gene expression experiments indicated that HSF1 is transcriptionally regulated in fat by agents that modulate cAMP levels, by cold exposure, and by pharmacological stimulation of β-adrenergic signaling. An in silico promoter analysis helped identify a putative response element for activating transcription factor 3 (ATF3) at −258 to −250 base pairs from the HSF1 transcriptional start site, and electrophoretic mobility shift and ChIP assays confirmed ATF3 binding to this sequence. Furthermore, functional assays disclosed that ATF3 is necessary and sufficient for HSF1 regulation. Detailed gene expression analysis revealed that ATF3 is one of the most highly induced ATFs in thermogenic tissues of mice exposed to cold temperatures or treated with the β-adrenergic receptor agonist CL316,243 and that its expression is induced by modulators of cAMP levels in isolated adipocytes. To the best of our knowledge, our results show for the first time that HSF1 is transcriptionally controlled by ATF3 in response to classic stimuli that promote heat generation in thermogenic tissues.




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Inflammatory and mitogenic signals drive interleukin 23 subunit alpha (IL23A) secretion independent of IL12B in intestinal epithelial cells [Signal Transduction]

The heterodimeric cytokine interleukin-23 (IL-23 or IL23A/IL12B) is produced by dendritic cells and macrophages and promotes the proinflammatory and regenerative activities of T helper 17 (Th17) and innate lymphoid cells. A recent study has reported that IL-23 is also secreted by lung adenoma cells and generates an inflammatory and immune-suppressed stroma. Here, we observed that proinflammatory tumor necrosis factor (TNF)/NF-κB and mitogen-activated protein kinase (MAPK) signaling strongly induce IL23A expression in intestinal epithelial cells. Moreover, we identified a strong crosstalk between the NF-κB and MAPK/ERK kinase (MEK) pathways, involving the formation of a transcriptional enhancer complex consisting of proto-oncogene c-Jun (c-Jun), RELA proto-oncogene NF-κB subunit (RelA), RUNX family transcription factor 1 (RUNX1), and RUNX3. Collectively, these proteins induced IL23A secretion, confirmed by immunoprecipitation of endogenous IL23A from activated human colorectal cancer (CRC) cell culture supernatants. Interestingly, IL23A was likely secreted in a noncanonical form, as it was not detected by an ELISA specific for heterodimeric IL-23 likely because IL12B expression is absent in CRC cells. Given recent evidence that IL23A promotes tumor formation, we evaluated the efficacy of MAPK/NF-κB inhibitors in attenuating IL23A expression and found that the MEK inhibitor trametinib and BAY 11–7082 (an IKKα/IκB inhibitor) effectively inhibited IL23A in a subset of human CRC lines with mutant KRAS or BRAFV600E mutations. Together, these results indicate that proinflammatory and mitogenic signals dynamically regulate IL23A in epithelial cells. They further reveal its secretion in a noncanonical form independent of IL12B and that small-molecule inhibitors can attenuate IL23A secretion.




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Time-resolved Mass Spectrometry of Tyrosine Phosphorylation Sites in the Epidermal Growth Factor Receptor Signaling Network Reveals Dynamic Modules

Yi Zhang
Sep 1, 2005; 4:1240-1250
Research




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Quantitative Phosphoproteomics of Early Elicitor Signaling in Arabidopsis

Joris J. Benschop
Jul 1, 2007; 6:1198-1214
Research




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Quantitative Phosphoproteomics Applied to the Yeast Pheromone Signaling Pathway

Albrecht Gruhler
Mar 1, 2005; 4:310-327
Research




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{gamma}-Hydroxybutyrate does not mediate glucose inhibition of glucagon secretion [Signal Transduction]

Hypersecretion of glucagon from pancreatic α-cells strongly contributes to diabetic hyperglycemia. Moreover, failure of α-cells to increase glucagon secretion in response to falling blood glucose concentrations compromises the defense against hypoglycemia, a common complication in diabetes therapy. However, the mechanisms underlying glucose regulation of glucagon secretion are poorly understood and likely involve both α-cell–intrinsic and intraislet paracrine signaling. Among paracrine factors, glucose-stimulated release of the GABA metabolite γ-hydroxybutyric acid (GHB) from pancreatic β-cells might mediate glucose suppression of glucagon release via GHB receptors on α-cells. However, the direct effects of GHB on α-cell signaling and glucagon release have not been investigated. Here, we found that GHB (4–10 μm) lacked effects on the cytoplasmic concentrations of the secretion-regulating messengers Ca2+ and cAMP in mouse α-cells. Glucagon secretion from perifused mouse islets was also unaffected by GHB at both 1 and 7 mm glucose. The GHB receptor agonist 3-chloropropanoic acid and the antagonist NCS-382 had no effects on glucagon secretion and did not affect stimulation of secretion induced by a drop in glucose from 7 to 1 mm. Inhibition of endogenous GHB formation with the GABA transaminase inhibitor vigabatrin also failed to influence glucagon secretion at 1 mm glucose and did not prevent the suppressive effect of 7 mm glucose. In human islets, GHB tended to stimulate glucagon secretion at 1 mm glucose, an effect mimicked by 3-chloropropanoic acid. We conclude that GHB does not mediate the inhibitory effect of glucose on glucagon secretion.




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12-LOX catalyzes the oxidation of 2-arachidonoyl-lysolipids in platelets generating eicosanoid-lysolipids that are attenuated by iPLA2{gamma} knockout [Signal Transduction]

The canonical pathway of eicosanoid production in most mammalian cells is initiated by phospholipase A2-mediated release of arachidonic acid, followed by its enzymatic oxidation resulting in a vast array of eicosanoid products. However, recent work has demonstrated that the major phospholipase in mitochondria, iPLA2γ (patatin-like phospholipase domain containing 8 (PNPLA8)), possesses sn-1 specificity, with polyunsaturated fatty acids at the sn-2 position generating polyunsaturated sn-2-acyl lysophospholipids. Through strategic chemical derivatization, chiral chromatographic separation, and multistage tandem MS, here we first demonstrate that human platelet-type 12-lipoxygenase (12-LOX) can directly catalyze the regioselective and stereospecific oxidation of 2-arachidonoyl-lysophosphatidylcholine (2-AA-LPC) and 2-arachidonoyl-lysophosphatidylethanolamine (2-AA-LPE). Next, we identified these two eicosanoid-lysophospholipids in murine myocardium and in isolated platelets. Moreover, we observed robust increases in 2-AA-LPC, 2-AA-LPE, and their downstream 12-LOX oxidation products, 12(S)-HETE-LPC and 12(S)-HETE-LPE, in calcium ionophore (A23187)-stimulated murine platelets. Mechanistically, genetic ablation of iPLA2γ markedly decreased the calcium-stimulated production of 2-AA-LPC, 2-AA-LPE, and 12-HETE-lysophospholipids in mouse platelets. Importantly, a potent and selective 12-LOX inhibitor, ML355, significantly inhibited the production of 12-HETE-LPC and 12-HETE-LPE in activated platelets. Furthermore, we found that aging is accompanied by significant changes in 12-HETE-LPC in murine serum that were also markedly attenuated by iPLA2γ genetic ablation. Collectively, these results identify previously unknown iPLA2γ-initiated signaling pathways mediated by direct 12-LOX oxidation of 2-AA-LPC and 2-AA-LPE. This oxidation generates previously unrecognized eicosanoid-lysophospholipids that may serve as biomarkers for age-related diseases and could potentially be used as targets in therapeutic interventions.




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Cross-regulation between LUBAC and caspase-1 modulates cell death and inflammation [Signal Transduction]

The linear ubiquitin assembly complex (LUBAC) is an essential component of the innate and adaptive immune system. Modification of cellular substrates with linear polyubiquitin chains is a key regulatory step in signal transduction that impacts cell death and inflammatory signaling downstream of various innate immunity receptors. Loss-of-function mutations in the LUBAC components HOIP and HOIL-1 yield a systemic autoinflammatory disease in humans, whereas their genetic ablation is embryonically lethal in mice. Deficiency of the LUBAC adaptor protein Sharpin results in a multi-organ inflammatory disease in mice characterized by chronic proliferative dermatitis (cpdm), which is propagated by TNFR1-induced and RIPK1-mediated keratinocyte cell death. We have previously shown that caspase-1 and -11 promoted the dermatitis pathology of cpdm mice and mediated cell death in the skin. Here, we describe a reciprocal regulation of caspase-1 and LUBAC activities in keratinocytes. We show that LUBAC interacted with caspase-1 via HOIP and modified its CARD domain with linear polyubiquitin and that depletion of HOIP or Sharpin resulted in heightened caspase-1 activation and cell death in response to inflammasome activation, unlike what is observed in macrophages. Reciprocally, caspase-1, as well as caspase-8, regulated LUBAC activity by proteolytically processing HOIP at Asp-348 and Asp-387 during the execution of cell death. HOIP processing impeded substrate ubiquitination in the NF-κB pathway and resulted in enhanced apoptosis. These results highlight a regulatory mechanism underlying efficient apoptosis in keratinocytes and provide further evidence of a cross-talk between inflammatory and cell death pathways.




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Learning the ABCs of ATP release [Signal Transduction]

ATP plays important roles outside the cell, but the mechanism by which it is arrives in the extracellular environment is not clear. Dunn et al. now show that decreases in cellular cholesterol levels mediated by the ABCG1 transporter increase ATP release by volume-regulated anion channels under hypotonic conditions. Importantly, these results may imply that cells that handle cholesterol differently might experience differential extracellular ATP release during hypotonicity.




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ABC transporters control ATP release through cholesterol-dependent volume-regulated anion channel activity [Signal Transduction]

Purinergic signaling by extracellular ATP regulates a variety of cellular events and is implicated in both normal physiology and pathophysiology. Several molecules have been associated with the release of ATP and other small molecules, but their precise contributions have been difficult to assess because of their complexity and heterogeneity. Here, we report on the results of a gain-of-function screen for modulators of hypotonicity-induced ATP release using HEK-293 cells and murine cerebellar granule neurons, along with bioluminescence, calcium FLIPR, and short hairpin RNA–based gene-silencing assays. This screen utilized the most extensive genome-wide ORF collection to date, covering 90% of human, nonredundant, protein-encoding genes. We identified two ABCG1 (ABC subfamily G member 1) variants, which regulate cellular cholesterol, as modulators of hypotonicity-induced ATP release. We found that cholesterol levels control volume-regulated anion channel–dependent ATP release. These findings reveal novel mechanisms for the regulation of ATP release and volume-regulated anion channel activity and provide critical links among cellular status, cholesterol, and purinergic signaling.




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G{alpha}q splice variants mediate phototransduction, rhodopsin synthesis, and retinal integrity in Drosophila [Signal Transduction]

Heterotrimeric G proteins mediate a variety of signaling processes by coupling G protein–coupled receptors to intracellular effector molecules. In Drosophila, the Gαq gene encodes several Gαq splice variants, with the Gαq1 isoform protein playing a major role in fly phototransduction. However, Gαq1 null mutant flies still exhibit a residual light response, indicating that other Gαq splice variants or additional Gq α subunits are involved in phototransduction. Here, we isolated a mutant fly with no detectable light responses, decreased rhodopsin (Rh) levels, and rapid retinal degeneration. Using electrophysiological and genetic studies, biochemical assays, immunoblotting, real-time RT-PCR, and EM analysis, we found that mutations in the Gαq gene disrupt light responses and demonstrate that the Gαq3 isoform protein is responsible for the residual light response in Gαq1 null mutants. Moreover, we report that Gαq3 mediates rhodopsin synthesis. Depletion of all Gαq splice variants led to rapid light-dependent retinal degeneration, due to the formation stable Rh1-arrestin 2 (Arr2) complexes. Our findings clarify essential roles of several different Gαq splice variants in phototransduction and retinal integrity in Drosophila and reveal that Gαq3 functions in rhodopsin synthesis.




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NF-{kappa}B mediates lipopolysaccharide-induced alternative pre-mRNA splicing of MyD88 in mouse macrophages [Signal Transduction]

Although a robust inflammatory response is needed to combat infection, this response must ultimately be terminated to prevent chronic inflammation. One mechanism that terminates inflammatory signaling is the production of alternative mRNA splice forms in the Toll-like receptor (TLR) signaling pathway. Whereas most genes in the TLR pathway encode positive mediators of inflammatory signaling, several, including that encoding the MyD88 signaling adaptor, also produce alternative spliced mRNA isoforms that encode dominant-negative inhibitors of the response. Production of these negatively acting alternatively spliced isoforms is induced by stimulation with the TLR4 agonist lipopolysaccharide (LPS); thus, this alternative pre-mRNA splicing represents a negative feedback loop that terminates TLR signaling and prevents chronic inflammation. In the current study, we investigated the mechanisms regulating the LPS-induced alternative pre-mRNA splicing of the MyD88 transcript in murine macrophages. We found that 1) the induction of the alternatively spliced MyD88 form is due to alternative pre-mRNA splicing and not caused by another RNA regulatory mechanism, 2) MyD88 splicing is regulated by both the MyD88- and TRIF-dependent arms of the TLR signaling pathway, 3) MyD88 splicing is regulated by the NF-κB transcription factor, and 4) NF-κB likely regulates MyD88 alternative pre-mRNA splicing per se rather than regulating splicing indirectly by altering MyD88 transcription. We conclude that alternative splicing of MyD88 may provide a sensitive mechanism that ensures robust termination of inflammation for tissue repair and restoration of normal tissue homeostasis once an infection is controlled.




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Biophysical characterization of SARAH domain-mediated multimerization of Hippo pathway complexes in Drosophila [Signal Transduction]

Hippo pathway signaling limits cell growth and proliferation and maintains the stem-cell niche. These cellular events result from the coordinated activity of a core kinase cassette that is regulated, in part, by interactions involving Hippo, Salvador, and dRassF. These interactions are mediated by a conserved coiled-coil domain, termed SARAH, in each of these proteins. SARAH domain–mediated homodimerization of Hippo kinase leads to autophosphorylation and activation. Paradoxically, SARAH domain–mediated heterodimerization between Hippo and Salvador enhances Hippo kinase activity in cells, whereas complex formation with dRassF inhibits it. To better understand the mechanism by which each complex distinctly modulates Hippo kinase and pathway activity, here we biophysically characterized the entire suite of SARAH domain–mediated complexes. We purified the three SARAH domains from Drosophila melanogaster and performed an unbiased pulldown assay to identify all possible interactions, revealing that isolated SARAH domains are sufficient to recapitulate the cellular assemblies and that Hippo is a universal binding partner. Additionally, we found that the Salvador SARAH domain homodimerizes and demonstrate that this interaction is conserved in Salvador's mammalian homolog. Using native MS, we show that each of these complexes is dimeric in solution. We also measured the stability of each SARAH domain complex, finding that despite similarities at both the sequence and structural levels, SARAH domain complexes differ in stability. The identity, stoichiometry, and stability of these interactions characterized here comprehensively reveal the nature of SARAH domain–mediated complex formation and provide mechanistic insights into how SARAH domain–mediated interactions influence Hippo pathway activity.




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Mechanistic insights explain the transforming potential of the T507K substitution in the protein-tyrosine phosphatase SHP2 [Signal Transduction]

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.




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The focal adhesion protein kindlin-2 controls mitotic spindle assembly by inhibiting histone deacetylase 6 and maintaining {alpha}-tubulin acetylation [Signal Transduction]

Kindlins are focal adhesion proteins that regulate integrin activation and outside-in signaling. The kindlin family consists of three members, kindlin-1, -2, and -3. Kindlin-2 is widely expressed in multiple cell types, except those from the hematopoietic lineage. A previous study has reported that the Drosophila Fit1 protein (an ortholog of kindlin-2) prevents abnormal spindle assembly; however, the mechanism remains unknown. Here, we show that kindlin-2 maintains spindle integrity in mitotic human cells. The human neuroblastoma SH-SY5Y cell line expresses only kindlin-2, and we found that when SH-SY5Y cells are depleted of kindlin-2, they exhibit pronounced spindle abnormalities and delayed mitosis. Of note, acetylation of α-tubulin, which maintains microtubule flexibility and stability, was diminished in the kindlin-2–depleted cells. Mechanistically, we found that kindlin-2 maintains α-tubulin acetylation by inhibiting the microtubule-associated deacetylase histone deacetylase 6 (HDAC6) via a signaling pathway involving AKT Ser/Thr kinase (AKT)/glycogen synthase kinase 3β (GSK3β) or paxillin. We also provide evidence that prolonged hypoxia down-regulates kindlin-2 expression, leading to spindle abnormalities not only in the SH-SY5Y cell line, but also cell lines derived from colon and breast tissues. The findings of our study highlight that kindlin-2 regulates mitotic spindle assembly and that this process is perturbed in cancer cells in a hypoxic environment.