Chemical key to cell division revealed

In each of our cells, most of the genetic material is packaged safely within the nucleus, which is protected by a double membrane. The biochemistry behind how this membrane transforms when cells divide has finally been unravelled, offering insights that could provide new ways of fighting cancer and some rare genetic disorders.

During cell division, the membrane that surrounds the nucleus breaks down and reforms in the two daughter cells. Researchers have been split on the precise mechanisms that govern membrane reformation. One view is that proteins alone control the membrane's transformations. Another possibility is that changes in lipids – a vast group of fat-related compounds – are responsible.

Experiments had failed to show which of these two ideas was right, because it was difficult to alter lipid levels in specific compartments of cells without affecting other cellular processes.

Banafshe Larijani at Cancer Research UK's London Research Institute and her colleagues have now overcome that hurdle. They came up with a technique that transforms a type of lipid called a diacylglycerol (DAG) into another lipid, within the nuclear membrane.

Chemical cascade

The technique involves inserting two fragments of DNA into the nucleus of a cell. This causes the cell to make two proteins: the first attaches itself to the nuclear membrane, the second floats around the cell. Adding a drug – rapalogue – to the mix causes the second protein to stick to the first, which in turn causes a chemical cascade that transforms the DAG into a different kind of lipid.

Crucially, they targeted a form of DAG that does not bind to proteins, so converting it into a different lipid does not affect any processes involving proteins in the cell.

The team tested the effect of this lipid manipulation on cell division in monkey and human cancer cells. The lower the level of DAG present in the nuclear membrane, the greater the membrane malformation and chance of cell death.

This demonstrates that lipids play a role in nuclear membrane reformation that does not depend on proteins.

Larijani says it "opens the door to finding ways to kill cancerous cells" by focusing on lipids that are important to the nuclear membrane's development.

Sausage pieces

As the nucleus divides, sausage-shaped fragments of its membrane float around the cell. The fragments have curved ends, and Larijani says that changes in lipid composition generate these curves, without which the fragments cannot reassemble correctly into new membranes.

More than a dozen rare genetic conditions such as Hutchinson-Gilford progeria syndrome, which is characterised by premature ageing in children, have been linked to irregularities in cell division. A better understanding of the way the nuclear membrane forms when cells divide could be key to treating these disorders.

The research also offers a new focus for preventing the irregular cell division that underlies many cancers.

"As a result of this work we now know with confidence that DAG plays a structural role in membrane dynamics," says Vytas Bankaitis, at the Texas A&M Health Science Center in College Station, who was not involved in the study. "If we could find a molecule with suitable characteristics, this manipulation could be done [in humans], which is something that has not really been considered before."

Journal reference: PLoS ONE DOI: 10.1371/journal.pone.0051150

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4 ex-SMRT bus drivers from China charged with instigating strike granted bail

SINGAPORE: The four ex-SMRT drivers from China who have been charged with instigating an illegal strike have been granted bail on Thursday.

He Jun Ling, who faces two charges of inciting SMRT drivers to take part in the strike on 26 and 27 November, was granted bail of S$20,000. His passport will have to be impounded.

According to court documents, He, 32, also made an online post about the strike on Chinese website Baidu, allegedly asking other workers to go on MC together.

Gao Yue Qiang, 32, Wang Xian Jie, 39 and Liu Xiang Ying, 33, were granted bail of S$10,000 each. Their passports will have to be impounded.

In response to a question from District Judge May Lucius Mesenas, the four accused said they're not able to raise the money.

Two officials from the Chinese embassy were present in court.

- CNA/ck

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Bask in Earth's nighttime glow as seen from space

When the skies darken and the lights flicker on, the areas of Earth we populate gain a surreal glow that traces our existence in a breathtaking way.

A new series of photos released by NASA and the National Oceanic and Atmospheric Administration's jointly-operated Suomi NPP satellite gives us a clearer view than ever before at our illuminated world during nighttime. Perhaps you could compare the view to a series of electrified blood vessels and arteries.

CNET photojournalist James Martin compiled a gallery of these stunning images from the aforementioned agencies that shows off the amazing electric show that comes from continents such as the suburban sprawl of North America to the blazing oil fields of the Middle East. The project, known as the "Black Marble," required 312 orbits and the extremely powerful Visible Infrared Imaging Radiometer Suite (VIIRS) sensor to capture 2.5 terabytes of pictures. Cloudless shots compiled from the massive amount of data was then sewn on to the classic 1994 'Blue Marble' imagery for the clearest glimpse of visible light at night seen yet.

You can tell the dramatic examples of how life differs from country to country in the series of photos, such as the sweeping darkness over the Midwest U.S. and the bright coastal areas, or the stark contrast of power usage between the dimly lit North Korea and the hyper-bright South Korea. Additionally, if you look closely at the picture of Australia, you'll notice half the continent lit up from the wildfires that occurred earlier this year.

What's your favorite angle of these amazing shots?

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A 2020 Rover Return to Mars?

NASA is so delighted with Curiosity's Mars mission that the agency wants to do it all again in 2020, with the possibility of identifying and storing some rocks for a future sample return to Earth.

The formal announcement, made at the American Geophysical Union's annual fall meeting, represents a triumph for the NASA Mars program, which had fallen on hard times due to steep budget cuts. But NASA associate administrator for science John Grunsfeld said that the agency has the funds to build and operate a second Curiosity-style rover, largely because it has a lot of spare parts and an engineering and science team that knows how to develop a follow-on expedition.

"The new science rover builds off the tremendous success from Curiosity and will have new instruments," Grunsfeld said. Curiosity II is projected to cost $1.5 billion—compared with the $2.5 billion price tag for the rover now on Mars—and will require congressional approval.

While the 2020 rover will have the same one-ton chassis as Curiosity—and could use the same sky crane technology involved in the "seven minutes of terror"—it will have different instruments and, many hope, the capacity to cache a Mars rock for later pickup and delivery to researchers on Earth. Curiosity and the other Mars rovers, satellites, and probes have garnered substantial knowledge about the Red Planet in recent decades, but planetary scientists say no Mars-based investigations can be nearly as instructive as studying a sample in person here on Earth.

(Video: Mars Rover's "Seven Minutes of Terror.")

Return to Sender

That's why "sample return" has topped several comprehensive reviews of what NASA should focus on for the next decade regarding Mars.

"There is absolutely no doubt that this rover has the capability to collect and cache a suite of magnificent samples," said astronomer Steven Squyres, with Cornell University in New York, who led a "decadal survey" of what scientists want to see happen in the field of planetary science in the years ahead. "We have a proven system now for landing a substantial payload on Mars, and that's what we need to enable sample return."

The decision about whether the second rover will be able to collect and "cache" a sample will be up to a "science definition team" that will meet in the years ahead to weigh the pros and cons of focusing the rover's activity on that task.  

As currently imagined, bringing a rock sample back to Earth would require three missions: one to select, pick up, and store the sample; a second to pick it up and fly it into a Mars orbit; and a third to take it from Mars back to Earth.

"A sample return would rely on all the Mars missions before it," said Scott Hubbard, formerly NASA's "Mars Czar," who is now at Stanford University. "Finding the right rocks from the right areas, and then being able to get there, involves science and technology we've learned over the decades."

Renewed Interest

Clearly, Curiosity's success has changed the thinking about Mars exploration, said Hubbard. He was a vocal critic of the Obama Administration's decision earlier this year to cut back on the Mars program as part of agency belt-tightening but now is "delighted" by this renewed initiative.

(Explore an interactive time line of Mars exploration in National Geographic magazine.)

More than 50 million people watched NASA coverage of Curiosity's landing and cheered the rover's success, Hubbard said. If things had turned out differently with Curiosity, "we'd be having a very different conversation about the Mars program now."

(See "Curiosity Landing on Mars Greeted With Whoops and Tears of Jubilation.")

If Congress gives the green light, the 2020 rover would be the only $1 billion-plus "flagship" mission—NASA's largest and most expensive class of projects—in the agency's planetary division in the next decade. There are many other less ambitious projects to other planets, asteroids, moons, and comets in the works, but none are flagships. That has left some planetary scientists not involved with Mars unhappy with NASA's heavy Martian focus.

Future Plans

While the announcement of the 2020 rover mission set the Mars community abuzz, NASA also outlined a series of smaller missions that will precede it. The MAVEN spacecraft, set to launch next year, will study the Martian atmosphere in unprecedented detail; a lander planned for 2018 will study the Red Planet's crust and interior; and NASA will renew its promise to participate in a European life-detection mission in 2018. NASA had signed an agreement in 2009 to partner with the European Space Agency on that mission but had to back out earlier this year because of budget constraints.

NASA said that a request for proposals would go out soon, soliciting ideas about science instruments that might be on the rover. And as for a sample return system, at this stage all that's required is the ability to identify good samples, collect them, and then store them inside the rover.

"They can wait there on Mars for some time as we figure out how to pick them up," Squyres said. "After all, they're rocks."

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McAfee Arrested for Entering Guatemala Illegally

Eccentric software tycoon John McAfee, wanted in Belize for questioning in the shooting death of his neighbor, has been arrested in Guatemala for entering the country illegally, his Guatemala attorney told ABC News.

Before McAfee's arrest, he told ABC News in an exclusive interview he would be seeking asylum in Guatemala. McAfee was arrested by the Central American country's immigration police and not the national police, said his attorney, who was confident his client would be released within hours.

"Thank God I am in a place where there is some sanity," said McAfee, 67, before his arrest. "I chose Guatemala carefully."

McAfee said that in Guatemala, the locals aren't surprised when he says the Belizean government is out to kill him.

"Instead of going, 'You're crazy,' they go, 'Yeah, of course they are,'" he said. "It's like, finally, I understand people who understand the system here."

But McAfee added he has not ruled out moving back to the United States, where he made his fortune as the inventor of anti-virus software, and that despite losing much of his fortune he still has more money than he could ever spend.

In his interview with ABC News, a jittery, animated but candid McAfee called the media's representation of him a "nightmare that is about to explode," and said he's prepared to prove his sanity.

McAfee has been on the run from police in Belize since the Nov. 10 murder of his neighbor, fellow American expatriate Greg Faull.

During his three-week journey, said McAfee, he disguised himself as handicapped, dyed his hair seven times and hid in many different places during his three-week journey.

He dismissed accounts of erratic behavior and reports that he had been using the synthetic drug bath salts. He said he had never used the drug, and said statements that he had were part of an elaborate prank.

Johan Ordonez/AFP/Getty Images

John McAfee Interview: Software Mogul Leaves Belize Watch Video

John McAfee Interview: Software Millionaire on the Run Watch Video

John McAfee: Software Millionaire Not Officially a Suspect Watch Video

Investigators said that McAfee was not a suspect in the death of the former developer, who was found shot in the head in his house on the resort island of San Pedro, but that they wanted to question him.

McAfee told ABC News that the poisoning death of his dogs and the murder just hours later of Faull, who had complained about his dogs, was a coincidence.

McAfee has been hiding from police ever since Faull's death -- but Telesforo Guerra, McAfee's lawyer in Guatemala, said the tactic was born out of necessity, not guilt.

"You don't have to believe what the police say," Guerra told ABC News. "Even though they say he is not a suspect they were trying to capture him."

Guerra, who is a former attorney general of Guatemala, said it would take two to three weeks to secure asylum for his client.

According to McAfee, Guerra is also the uncle of McAfee's 20-year-old girlfriend, Samantha. McAfee said the government raided his beachfront home and threatened Samantha's family.

"Fifteen armed soldiers come in and personally kidnap my housekeeper, threaten Sam's father with torture and haul away half a million dollars of my s***," claimed McAfee. "If they're not after me, then why all these raids? There've been eight raids!"

Before his arrest, McAfee said he would hold a press conference on Thursday in Guatemala City to announce his asylum bid. He has offered to answer questions from Belizean law enforcement over the phone, and denied any involvement in Faull's death.

False Report of McAfee Arrest on Mexico Border

Over the weekend, a post on McAfee's blog claimed that he had been detained on the Belizean/Mexico border.

On Monday, a follow-up post said that the "John McAfee" taken into custody was actually a "double" who was carrying a North Korean passport with McAfee's name.

That post claimed that McAfee had already escaped Belize and was on the run with Samantha and two reporters from Vice Magazine.

McAfee did not reveal his location in that post, and a spokesman for Belize's National Security Ministry, Raphael Martinez, told ABC News on Monday that no one by McAfee's name was ever detained at the border and that Belizean security officials believed McAfee was still in their country.

However, a photo posted by Vice magazine on Monday with their article, "We Are With John McAfee Right Now, Suckers," apparently had been taken on an iPhone 4S and had location information embedded in it that revealed the exact coordinates where the photo was taken -- in the Rio Dulce National Park in Guatemala -- as reported by Wired.com.

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When is a baby too premature to save?

It was never easy, but trying to decide whether to save extremely premature babies just got harder.

A study called EPICure compared the fates of babies born 22 to 26 weeks into pregnancy in the UK in 1995 with similar babies born in 2006. In this 11-year period, the babies surviving their first week rose from 40 to 53 per cent. But an accompanying study comparing the fate of survivors at age 3 found that the proportion developing severe disabilities was unchanged, at just under 1 in 5.

"We've increased survival, but it's confined to the first week of life," says Kate Costeloe of Queen Mary, University of London, author of the first study. "Yet the pattern of death and health problems is strikingly similar between the two periods."

The absolute numbers of premature babies born over the 11 year period increased by 44 per cent, from 666 in 1995 to 959 in 2006. This meant that the absolute numbers of children with severe disabilities such as blindness, deafness or lameness also rose, increasing the burden on health, educational and social services.

Lifelong disability

"As the number of children that survive preterm birth continues to rise, so will the number who experience disability throughout their lives," says Neil Marlow of University College London, who led the second study.

By far the worst outcomes were for the youngest babies, with 45 per cent of those born at 22 or 23 weeks in 2006 developing disabilities compared with 20 per cent of those born at 26 weeks. In 1995 only two babies survived after being born at 22 weeks. In 2006, three did.

In 2006, a panel of UK ethicists concluded that babies born at 22 weeks should be allowed to die, as with babies born at or before 23 weeks in France and Holland.

Journal references: BMJ, Costeloe et al, DOI: 10.1136/bmj.e7976; Marlow et al, DOI: 10.1136/bmj.e7961

If you would like to reuse any content from New Scientist, either in print or online, please contact the syndication department first for permission. New Scientist does not own rights to photos, but there are a variety of licensing options available for use of articles and graphics we own the copyright to.

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Thais pack Bangkok for king's birthday celebration

BANGKOK: Tens of thousands of Thais crowded central Bangkok on Wednesday for a rare address by King Bhumibol Adulyadej, the world's longest reigning monarch, as part of celebrations for his 85th birthday.

Television images showed a sea of supporters of the revered king, many wearing yellow symbolising Monday, the day of his birth, and waving royal and Thai flags.

At least 200,000 people were expected to attend the speech from a balcony at the Anantasamakom Throne Hall in front of the Royal Plaza in the capital's historic district.

Crowds lined the streets chanting "long live the king!" along the route of the royal motorcade as it made its way from the hospital where the king has lived for three years after suffering a respiratory illness in 2009.

Bhumibol, who has served for 66 years, suffered a minor brain bleed in July, but has since made several official appearances including meeting Barack Obama during the US president's visit to the country last month.

Thailand's Queen Sirikit was not among the members of the royal family accompanying the king on Wednesday.

Doctors treating the 80-year-old queen, who was diagnosed with a slight loss of blood flow to the brain after being taken ill in July, said she was too weak to attend the ceremony, according to a statement from the palace on Tuesday.

Any discussion of the royal family is extremely sensitive in politically-turbulent Thailand, where the palace has been silent over the organisation of the eventual succession.

Royal Plaza was the heart of anti-government demonstrations in November that saw clashes between police and protesters in the city.

The rally -- attended by members of the influential monarchist "Yellow Shirts" -- was the latest street unrest in Thailand's long-running political crisis pitting Thai royalists against supporters of ousted premier Thaksin Shinawatra and the current government led by his sister Yingluck.

- AFP/ck

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Forget about the Mars rover -- how about we build a Death Star?

The real Death Star must have really been murder on the Empire's wallet. This model hanging in the Los Angeles Convention Center for Celebration IV was probably cheaper.

(Credit:
Daniel Terdiman/CNET)

In the off-chance that during their deep-space explorations, the Voyager spacecrafts encounter an Alderaan-like planet that the U.S. government deems ripe for destruction, a petition has been created that advocates the creation of a Death Star.

With the U.S. approaching the "fiscal cliff," backers suggest that creation of the universe's ultimate weapon might give the economy a much-needed boost, according to the petition hosted on the White House's We The People platform.

By focusing our defense resources into a space-superiority platform and weapon system such as a Death Star, the government can spur job creation in the fields of construction, engineering, space exploration, and more, and strengthen our national defense.

The petition offers no estimates on how much it will cost or how long it will take to construct a moon-size military battlestation armed with a planet-destroying superlaser, but the backers hope to begin construction by 2016. (A study earlier this year by economics students at Lehigh University estimated that construction would require a quadrillion tons of steel, which would take roughly 800,000 years to manufacture.)

But backers are going need more than The Force to get this one off the ground. The petition, which was launched November 14, has 10 days left to achieve its goal of attracting 25,000 signatures; as of this writing, it has a little more than 2,500 signatures, only about 10 percent of its target.

However, they will have to persuade the emperor -- err, president -- that there is another peaceful planet without weapons out there somewhere that is in need of destruction. Come to think of it, maybe it's time to ramp up funding for SETI efforts as well.

[Via Mashable]

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Scientific Results From Challenger Deep

Jane J. Lee

The spotlight is shining once again on the deepest ecosystems in the ocean—Challenger Deep in the Mariana Trench (map) and the New Britain Trench near Papua New Guinea. At a presentation today at the American Geophysical Union's conference in San Francisco, attendees got a glimpse into these mysterious ecosystems nearly 7 miles (11 kilometers) down, the former visited by filmmaker James Cameron during a historic dive earlier this year.

Microbiologist Douglas Bartlett with the University of California, San Diego described crustaceans called amphipods—oceanic cousins to pill bugs—that were collected from the New Britain Trench and grow to enormous sizes five miles (eight kilometers) down. Normally less than an inch (one to two centimeters) long in other deep-sea areas, the amphipods collected on the expedition measured 7 inches (17 centimeters). (Related: "Deep-Sea, Shrimp-like Creatures Survive by Eating Wood.")

Bartlett also noted that sea cucumbers, some of which may be new species, dominated many of the areas the team sampled in the New Britain Trench. The expedition visited this area before the dive to Challenger Deep.

Marine geologist Patricia Fryer with the University of Hawaii described some of the deepest seeps yet discovered. These seeps, where water heated by chemical reactions in the rocks percolates up through the seafloor and into the ocean, could offer hints of how life originated on Earth.

And astrobiologist Kevin Hand with the Jet Propulsion Laboratory in Pasadena, California, spoke about how life in these stygian ecosystems, powered by chemical reactions, could parallel the evolution of life on other planets.

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Subway Push Murder Suspect Implicated Self: Police

A suspect believed to be responsible for throwing a man into the path of an oncoming New York City subway train who was taken into custody today has made statements implicating himself, police said.

According to Deputy Commissioner for Public Information Paul Browne, the suspect has been questioned by police since at least early afternoon and while the suspect is in police custody, he has not been officially charged.

Police are continuing to question the suspect and more lineups have been scheduled for tomorrow, Browne said.

Police have not released the suspect's name but began questioning him Tuesday afternoon about the death of Ki-Suck Han, 58, of Queens, N.Y.

Han was tossed onto the subway track at 49th Street and Seventh Avenue around 12:30 p.m. Monday after Han confronted a mumbling man who was alarming other passengers on the train platform. Han tried to scramble back onto the platform, but was crushed by an oncoming train.

The suspect fled the station, prompting a police dragnet for a man described by witnesses and see on surveillance video as a 6-foot-tall, 200-pound black man wearing dreadlocks in his hair.

Witnesses tried to revive the victim after he was hit and provided descriptions of the suspect to police.

Dr. Laura Kaplan, medical resident at Beth Israel Medical Center who was standing on the platform during the incident rushed to give Han aid after he was hit, she said in a statement released by her medical practice today.

New York Police Department

Bystanders Pull Mom, Son From Subway Tracks Watch Video

"A security guard and I performed 3-4 minutes of chest compressions. I hope the family may find some comfort in knowing about the kindness of these good Samaritans, as they endure this terrible loss," Kaplan said.

"I would like the family to know that many people in the station tried to help Mr. Han by alerting the subway personnel," she said.

Kaplan said she wanted to console the family of Han, who she called "a brave man trying to protect other passengers that he did not know."

The suspect had reportedly been mumbling to himself and disturbing other passengers, according to ABC News affiliate WABC. Police told WABC that the suspect could be mentally disturbed.

The suspect could be heard arguing with Han just moments before he hurled Han onto the track bed, according to surveillance video released by the police. The suspect is heard telling the victim to stand in line and "wait for the R train."

A freelance photographer for the New York Post was on the platform and said he ran towards the train flashing his camera hoping to alert the train to stop in time, but the train caught Han against the shoulder deep platform wall.

The photographer, R. Umar Abbasi, caught an eerie photo of Han with his head and arms above the platform and staring at the oncoming train.

Han was treated by EMS workers on the platform for traumatic arrest and rushed to Roosevelt Hospital, where he was pronounced dead, according to the Fire Department of New York.

"I just heard people yelling. The train came to an abrupt stop about three-quarters into the station and that's when I heard a man was hit by a train," Patrick Gomez told ABC News affiliate WABC.

Police set up a command post outside the train station Monday night searching nearby surveillance cameras to try and get a clear image of the suspect, reports WABC. They said Tuesday that the investigation is ongoing.

Anyone with information is asked to call Crime Stoppers at 1-800-577-TIPS (8477). The public can also submit tips by logging onto the Crime Stoppers website at www.nypdcrimestoppers.com or by texting their tips to 274637 (CRIMES) then enter TIP577. All calls are strictly confidential.

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