Osiris Martinez-Guzman, Mathilda M. Willoughby, Arushi Saini, Jonathan V. Dietz, Iryna Bohovych, Amy E. Medlock, Oleh Khalimonchuk, and Amit R. Reddi

Heme is a cofactor and signaling molecule that is essential for much of aerobic life. All heme-dependent processes in eukaryotes require that heme is trafficked from its site of synthesis in the mitochondria to hemoproteins located throughout the cell. However, the mechanisms governing the mobilization of heme out of the mitochondria, and the spatio-temporal dynamics of these processes, are poorly understood. Herein, using genetically encoded fluorescent heme sensors, we developed a live cell assay to monitor heme distribution dynamics between the mitochondrial inner-membrane, where heme is synthesized, and the mitochondrial matrix, cytosol, and nucleus. Surprisingly, heme trafficking to the nucleus is ~25% faster than to the cytosol or mitochondrial matrix, which are nearly identical, potentially supporting a role for heme as a mitochondrial-nuclear retrograde signal. Moreover, we discovered that the heme synthetic enzyme, 5-aminolevulinic acid synthase (ALAS), and GTPases in control of the mitochondrial dynamics machinery, Mgm1 and Dnm1, and ER contact sites, Gem1, regulate the flow of heme between the mitochondria and nucleus. Overall, our results indicate that there are parallel pathways for the distribution of bioavailable heme.

Julian Chollet, Alexander Dünkler, Anne Bäuerle, Laura Vivero-Pol, Medhanie A. Mulaw, Thomas Gronemeyer, and Nils Johnsson

Yeast cells select the position of their new bud at the beginning of each cell cycle. The recruitment of the septins to this prospective bud site is one of the critical events in a complex assembly pathway that culminates in the outgrowth of a new daughter cell. Hereby, the septin-rods follow the high concentration of Cdc42_GTP that is generated by the focused localization of its GEF Cdc24. We show that shortly before budding Cdc24 not only activates Cdc42 but also transiently interacts with Cdc11, the septin subunit that caps both ends of the septin rods. Mutations in Cdc24 reducing the affinity to Cdc11 impair septin recruitment and decrease the stability of the polarity patch. The interaction between septins and Cdc24 thus reinforces bud assembly at sites where septin structures are formed. Once the septins polymerize into the ring, Cdc24 is found at the cortex of the bud and directs its further outgrowth from this position.

During a press conference Friday, July 22 at the Smithsonian's National Air and Space Museum, NASA announced that Gale Crater will be the landing site for the Mars Science Laboratory. Scheduled to launch in late 2011 and arrive at Mars in August 2012, the Mars Science Laboratory is a rover that will assess the planet’s “habitability”—if it ever was, or is today, an environment able to support microbial life.

The post Gale Crater to be landing site for NASA’s Mars Science Laboratory appeared first on Smithsonian Insider.

Forensic anthropologists from the Smithsonian's National Museum of Natural History discover African remains at a Colonial burial site in Maryland. Follow them as they study the remains, reconstruct the face and body, and share what they learn about the African experience in the Chesapeake in the 1600s.

The post Smithsonian team examines African remains from a colonial burial site in Maryland appeared first on Smithsonian Insider.

The post Roland Kays, curator of mammals at the New York State Museum, discusses a new Smithsonian Website for sharing camera-trap images of wild animals appeared first on Smithsonian Insider.

Mark Torchin, a marine ecologist at the Smithsonian Tropical Research Institute (STRI) in Panama, talks about how he studies the parasites of invasive marine animals such as snails. Much of his research focuses on biological invasions and the dynamics between the host, the parasites and the surrounding ecosystem.

The post Meet our Scientist–Mark Torchin tracks invasive marine species and their parasites in Panama appeared first on Smithsonian Insider.

Learn how to use the Smithsonian Wild website to find amazing camera trap photos of mammals from around the world

The post Learn to use the Smithsonian Wild website of amazing animal photos! appeared first on Smithsonian Insider.

Get a quick tutorial on how to upload a story about your local culture and experiences to the Smithsonian’s storytelling website, located www.museumonmainstreet.org Museum on […]

The post Posting Your Story to Smithsonian’s Museum on Main Street Website appeared first on Smithsonian Insider.

The state's online registration for Covered California has been up for a couple of weeks, and reaction has been mixed.

Steve Julian: Business analyst, Mark Lacter, what's your take on how well Californians are getting into the Affordable Care Act?

Mark Lacter: It's hard to get a good read, Steve, because it's hard to measure the success of what is really a new marketplace.  If you're basing it on the number of unique visitors coming to the Covered California website, well, then the program clearly has attracted lots of interest - they had almost a million visitors during the first week of eligibility.  But, maybe a better measure would be the number of people whose applications actually have been received by the insurance companies that are going to handle the claims.  If that's your measuring stick, then the numbers have been far smaller so far.  Now, it's worth pointing out that California - and particularly L.A. County - have a higher percentage of households without insurance than other parts of the nation, and so you'd expect there to be lots of interest.

Julian: So the question, then, is how many folks turn into actual policyholders paying actual premiums each month.

Lacter: The truth is nobody knows, which is why state officials want to sign up as many people as possible in the early going when the program is getting so much attention.  This is especially true for younger and healthier people who are needed to help offset the cost of caring for older and sicker people.

Julian: And, that's also why any computer glitch can be such a headache...

Lacter: That's right.  Covered California did run into problems in the early going, but everybody agrees that things are going much better than the federal website, which is the default site used by folks in states that don't have their own program to oversee the health care laws.  That federal site has been an utter disaster.  So, by comparison, California is ahead of the game.

Julian: It's a work in progress, even here.

Lacter: Very much so.  The California website still doesn't have a way for enrollees to find out which doctors and hospitals are included in each health plan.  And, that's a big deal because  insurance companies are limiting the options available as a way of keeping premiums low.  So, it's possible that the doctor you had been using for your individual insurance plan will not be on the list of doctors that can be used for one of the cheaper plans.  Of course, for someone who doesn't have any health coverage, none of that is likely to matter.

Julian: And then, there's the continued threat of a U.S. default...

Lacter: You know, Steve, this is like watching the beginning of a bad traffic accident in slow motion - and we're all pretty helpless to do anything about it.  And, so are the financial markets, which are moving back and forth not based on what's going on with the economy or with any industry, but on the latest press conference out of Washington.  One thing we do know is that if the nation does go into quote-unquote default - and we're not even sure what that might mean - but if Wall Street and somehow declares this a major crisis, it's going to be bad.

Julian: Who gets hit?

Lacter: It'll impact anyone who has a retirement account, any business wanting to borrow money, and potentially it's going to impact the budgeting of the state.  You know, one of the things we were reminded of during the Great Recession was how reliant California has been on higher-income individuals who make a lot of their money through the stock market and other investments.  So, when those folks do well - as they have been over the last year - the state coffers will do well.  And when they don't, as was the case in 2008 and 2009, the state takes a huge hit because there's not enough tax dollars coming in.  Gov. Brown and others have tried to lessen the reliance on those top tiers - so far without success.

Julian: And the state's budget situation is so much better than it was a year or two ago.

Lacter: That's the real pity.  And, even if the House and Senate reach a temporary agreement on the debt ceiling, it's just a matter of weeks or months before another deadline crops up - and more uncertainty for the financial markets.  I guess Chick Hearn would have called this nervous time.

Mark Lacter writes for Los Angeles Magazine and pens the business blog at LA Observed.com.

This content is from Southern California Public Radio. View the original story at SCPR.org.

Obsessive in his collecting and emotionally invested in contributing to science and perpetuating knowledge, Palmer lived the adventurous yet nomadic life of a collector.

The post Remarkable ethnobotany collections of Edward Palmer highlighted in new Smithsonian Website appeared first on Smithsonian Insider.

Zebra mussels in the Great Lakes, lionfish in the Atlantic and pythons in the Everglades: Large creatures like these generally draw the spotlight when talking […]

The post DNA is trusty new weapon for detecting slime nets and other invasive marine parasites appeared first on Smithsonian Insider.

For the first time, a new public database will link genetic data with records of where and when the samples it was taken from were […]

The post A first: New website reveals origin of genetic samples and date collected appeared first on Smithsonian Insider.

The Earth’s changing climate could cause the extinction of up to a third of its parasite species by 2070, according to a global analysis reported […]

The post Study shows parasites may be among earliest victims of climate change appeared first on Smithsonian Insider.

Using mineralogical data, it is demonstrated that chemical simplicity measured as an amount of Shannon information per atom on average corresponds to higher symmetry measured as an order of the point group of a mineral, which provides a modern formulation of the Fedorov–Groth law.

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Many wild southern sea otters in California are infected with the parasite Toxoplasma gondii, yet the infection is fatal for only a fraction of sea otters, which has long puzzled the scientific community. A National Science Foundation-funded study identifies the parasite's specific strains that are killing southern sea otters, tracing them back to a bobcat and feral domestic cats from nearby watersheds. The study marks the first time a genetic link has been clearly established between the Toxoplasma strains in felid hosts and parasites causing fatal disease in marine wildlife. The study's results highlight how infectious agents like Toxoplasma can spread from cat feces on land to the sea, leading to detrimental impacts on marine wildlife.

Image credit: Trina Wood/UC Davis

In an August 18 letter, the U.S. Department of the Interior’s Office of Surface Mining Reclamation and Enforcement informed the National Academies of Sciences, Engineering, and Medicine that it should cease all work on a study of the potential health risks for people living near surface coal mine sites in Central Appalachia.

A new report from the National Academies of Sciences, Engineering, and Medicine recommends changes in the way that the U.S. Department of Energy manages science and technology (S&T) development in order to accelerate the cleanup of radioactive waste and contaminated soil, groundwater, and facilities at U.S. nuclear weapons sites.

A new report from the National Academies of Sciences, Engineering, and Medicine – which reviews a separate report by a federally funded laboratory that examines options for treating low-activity radioactive waste at the Hanford Nuclear Reservation -- is available for public comment until Oct. 31.

The U.S. Department of Energy’s plan to dilute and dispose of 34 metric tons of surplus plutonium in the Waste Isolation Pilot Plant (WIPP) in New Mexico is technically viable, provided that the plan’s implementation challenges and system vulnerabilities are resolved.

An unknown threat actor is exploiting vulnerabilities in plugins for which patches have been available for months, or even years

The post Almost a million WordPress websites targeted in massive campaign appeared first on WeLiveSecurity

The last two decades have seen a series of new construction waste policies management in Hong Kong. One of the most significant is an offsite construction waste sorting (CWS) programme which, since its implementation in 2006, has separated 5.11 million tonnes of construction waste into different materials. The researchers suggest that the study provides an important reference for other countries working to minimise construction waste.

A standardised method to help choose the most cost-effective measures to remediate contaminated sites has been developed by Austrian researchers. The method takes into account a wide range of factors, including the principles of sustainability.

Researchers in Berlin have demonstrated that urban wasteland areas can be used as suitable habitats for a range of grassland species. Using simple and cost-effective measures to sow grassland seed mixtures, they found that such areas flourished despite poor soil conditions and high levels of impact from people.

Twitter is warning users impersonating unsupported browsers to enable the original site theme that the legacy version will be shut down on June 1st, 2020. [...]

Researchers in Berlin have demonstrated that urban wasteland areas can be used as suitable habitats for a range of grassland species. Using simple and cost-effective measures to sow grassland seed mixtures, they found that such areas flourished despite poor soil conditions and high levels of impact from people.

Researchers have proposed a new indexing scheme to help decision-makers prioritise brownfield sites for redevelopment. The scheme scores potential sites according to socio-economic, smart growth and environmental dimensions. By giving users the flexibility to emphasise some aspects of development as more important than others, it can be adapted for use in different contexts.

Better methods are needed to monitor underwater gas leaks. A new study outlines a technique that uses sound to detect bubbles of escaped gas and could help produce more accurate measurements of gas leakage rates from carbon capture and storage (CCS) sites, pipelines and natural leakage sites.

Aeration technologies designed to help landfill waste break down faster need to be refined in order to reduce pollution, greenhouse gas emissions and the long-term costs associated with landfill. This is according to a recent review of landfill aeration, which outlines some of the different systems currently available and highlights the need for better monitoring and sharing of data.

A standardised method to help choose the most cost-effective measures to remediate contaminated sites has been developed by Austrian researchers. The method takes into account a wide range of factors, including the principles of sustainability.

A new study identifies ways to reduce the risks to water quality associated with underground CO2 storage. The study, based on laboratory tests, shows that CO2 leakage could pose a risk to overlying fresh groundwater. Careful storage site selection, coupled with regular site monitoring, is a pre-condition to reducing risks associated with CO2 leakage.

New research in harbours has explored the most influential environmental and human factors on the release of contaminants from sediment. The scientists suggest that the rate of release can vary considerably between locations and risk assessments of water pollution could be improved if they account for this.

To restore a river site to good ecological status involves comparing it to similar sites that have been far less affected by human activity. A recent study has established a set of guidelines that define an acceptable level of human pressure that can be used to identify these minimally disturbed sites and ensure consistent ecological assessment among EU Member States.

A recent study has developed a mapping system to show the impact on habitats and species caused by construction projects, such as dams, near Natura 2000 conservation areas. Using a Greek case study, the system was able to identify risks from a dam construction project to species including otters, toads and tortoises.

Careful choice of tree species and sites could transform plantations into refuges for woodland plant diversity, new research from Ireland suggests. Plantations of native species on or near historic woodland and those with adequate light levels below the tree canopy were found to support more plant species.

New research suggests that Natura 2000 sites are highly effective in minimising the number of endangered species of concern to European conservation. The findings may reduce concerns that poor coordination between Member States in setting up the European network of protected areas has led to inadequate protection of vulnerable species.

Connectivity between protected areas is vital for safeguarding many animals and plants. New research has shown that Natura 2000 sites are well connected across provincial borders in Germany, Italy and Spain. This is the result of strong coordination from central governments combined with good regional cooperation, the study???s authors conclude.

Offshore renewable energy sites may provide new 'stepping stone' habitats for marine species, a recent study suggests. They could allow some species to spread beyond their present range and help vulnerable creatures survive in the face of climate change. However, they may also allow harmful invasive species to spread, the researchers warn, and the effects of such projects must be assessed by examining their impacts on the ecosystem as a whole.

A new decision-making aid to identify the best type of management plan for Natura 2000 sites has been developed by researchers. Using extensive data on different facets of biodiversity and human impacts, the researchers created two indices to show where conservation measures need to be integrated with socio-economic development. This study used sites in Italy as a case study but the method is widely applicable to all Natura 2000 sites, the researchers stress.