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Preventing HIV from Infecting Human Cells

1/30/2011

University of Minnesota researchers carried out a study that concluded there might be a way of preventing HIV from infecting human cells.

HIV binds and destroys a certain human antiviral protein called APOBEC3F, and the U of M team figured out how, and said that a simple chemical change could turn APOBEC3F into a more effective antiviral agent.

The APOBECs are a family of antiviral proteins produced by the human body, that have a natural and one-of-a-kind ability to destroy HIV.

The problem is that HIV has evolved by using an accessory protein called Vif (virion infectivity factor) that degrades the APOBEC proteins and allows the virus to spread.

Lead author John Albin, a researcher in the laboratory of Reuben Harris, associate professor of biochemistry, molecular biology and biophysics in the College of Biological Sciences, and colleagues found out where Vif interacts with one antiviral protein, APOBEC3F, and proved that the connection can be interrupted by a simple chemical change on the surface of APOBEC3F.

They added that similar interactions also take place on the same surface of other members of this antiviral protein family.

Albin said that according to this, “the interaction between Vif and these antiviral APOBEC proteins could be blocked with a drug that would shield the Vif interaction region.

“Such an intervention has the potential to allow as many as seven natural antiviral drugs to spring into action and prevent HIV from spreading.”

The lab of Ruben Harris lab is trying to understand every level of this vital interaction between the APOBECs and HIV Vif.

Their discovery stresses the importance of a new approach in the fight against HIV/AIDS, that would try to stabilize and control the natural antiviral activity of some human proteins.

This way, in a not-so-far-away future, studies will have a more specific map of the physical interactions between Vif and APOBEC3 proteins, investigation of the potential for HIV to resist stabilizing changes in APOBEC3 proteins, and screens for drug-like compounds that help the cellular APOBECs destroy HIV.

Albin is a student in the Combined MD-PhD Training Program at the University of Minnesota Medical School, and through the Microbiology, Immunology & Cancer Biology PhD program, he is finishing his thesis, under Harris' guidance.

In 2003 and 2004, Harris contributed to the discovery of the APOBEC proteins' ability to counteract HIV infection, and in 2009 he won a grant from the Bill & Melinda Gates Foundation to explore ways of blocking HIV and APOBEC3 interaction.

His laboratory focuses on ways to harness mutations so that they destroy pathogens.

This new finding was published in the Journal of Biological Chemistry.

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Experts Want to Revive a Mammoth

1/30/2011

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After more than 10,000 years of absence, the mammoth may finally return to roam the Earth. The animal, which went extinct at the end of the Younger Dryas, may be engineered from the information contained in DNA found in frozen cells recovered from the Arctic permafrost.

At this point, there is no guarantee that the research group seeking to accomplish this will succeed, but, if they do, then the achievement would undoubtedly become one of the most impressive in science.

The group is confident in its success due to the fact that it has developed a technique to efficiently extract DNA from frozen cells. The genetic material recovered in this manner is then used with cloning technology to create a new individual.

<Tissue samples were obtained in the summer of 2010 from a frozen mammoth carcass discovered in Siberia by a team of Russian experts. They are being preserved in a research laboratory until they can be used in cloning.

“If a cloned embryo can be created, we need to discuss, before transplanting it into the womb, how to breed [the mammoth] and whether to display it to the public,” explains Akira Iritani.

“After the mammoth is born, we'll examine its ecology and genes to study why the species became extinct and other factors,” adds the expert, who is a professor emeritus at the Kyoto University.

He and his team are in charge of the efforts to revive mammoths. The Japanese experts believe that, if everything goes according to plan, a live mammoth could be born within five to six years tops.

The group plans to use an elephant as a surrogate mother for the mammoth. Cellular nuclei from the extinct beast will be inserted into an elephant egg cells, and then implanted into a female elephant.

The two creatures are theoretically similar enough to allow for a complication-free live birth, the scientists believe. They have been trying to clone a mammoth since 1997.

One of the most common problems they came across was the lack of usable mammoth cell nuclei. All the sample they retrieved from muscles or bones had their DNA damaged beyond use. A breakthrough came in 2008, when the samples that are to be used in the new study were found.

“The mammoth has no defects except that its tail was bit off. In terms of its state of preservation, this is the world's most valuable discovery,” says of the 2008 finding Alexei Tikhonov.

The expert is the deputy director of the Zoological Institute of the Russian Academy of Sciences, which keeps the samples in storage until they are used, Daily Galaxy reports.

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Plant-Digesting Microbe Genomes Figured Out

1/30/2011

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A collaboration of American researchers announces that it has successfully completed a long-term effort to characterize the genes and genomes of plant-digesting microbes that live in the rumen (forestomach) of cows and other ruminants.

These microorganisms hold no intrinsic value, but they are able to break down materials in the grass cows eat that no other class of animals can process. Finding out how they do this is key to developing new biofuel technologies, experts say.

Cellulose and hemicellulose are two materials in plants that are not only useless to humans, but also impossible to digest within our guts. In cows, they are capable of sustaining the animals, their offspring, and the human population benefiting from various food products.

The class of microbes the collaboration investigated has eluded scientific scrutiny for a very long time, as scientists found it impossible to grow and study them in the tightly-controlled confines of scientific laboratories.

The new study was conducted by experts at the US Department of Energy (DOE) Joint Genome Institute (JGI) and the Energy Biosciences Institute (EBI), and consisted of a massive-scale DNA sequencing effort.

In a paper published in the January 28 issue of the top journal Science, the team reveals that the new data could allow for the cheaper and more energy-effective processing or plant biomass. The inability to do so is a great obstacle in the path of using biofuels widely.

The goal of biofuel research is to turn plant biomass into sugar. But this process is tremendously energy-intensive, and requires a host of expensive technologies that make this alternative source of energy unfeasible.

“Microbes have evolved over millions of years to efficiently degrade recalcitrant biomass,” explains the lead investigator for the study, and the director of the JGI, Eddy Rubin.

“Communities of these organisms can be found in diverse ecosystems, such as in the rumen of cows, the guts of termites, in compost piles, as well as covering the forest floor,” he adds.

“Microbes have solved this challenge, overcoming the plant’s protective armor to secure nutrients, the rich energy source that enables them and the cow to thrive,” the expert goes on to say.

Using the new genetic data, researchers might become able to develop new approach for plant biomass conversion, which would aid the world get rid of dirty fossil fuels such as oil, natural gas and coal.

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Vaccines Save Lives - By Bill Gates

1/30/2011

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Bill’s thoughts about vaccines and polio, drawn on sketch paper.

My third annual letter is coming out in a few days. One of the major themes of the letter is the miracle of vaccines. Last year, Melinda and I announced that we were working together with partners to make this the Decade of Vaccines, and I wanted to use this year’s letter to explain why.

In particular, my letter focuses on the vaccine for polio, since it’s helped the world get to the threshold of something amazing: eradicating the disease altogether. We’re incredibly close and we need to finish the job.

We put together a video, called “Vaccines Save Lives,” to try to describe why vaccines are a miracle in a vivid way. I hope you enjoy it—and share it with your friends.

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New Research Paths for Curing Epilepsy and Stroke Found

1/8/2011

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A team of experts based at the UT Health Science Center San Antonio announce the discovery of two critically-important signaling molecules, that are capable of communicating across nerve cells in the human brain in order to regulate a host of essential processes.

Their interactions allow them to regulate electrical and chemical activity inside the human brain, which means that both of them need to function at full capacity in order for the cortex to work properly.

According to investigators, it may be that developing drugs capable of acting on these mechanisms is the next big step in addressing conditions such as stroke and epilepsy, among others.

The team conducted the new research on unsuspecting lab rats, but they say that the same type of interactions are at play in the human brain as well. The rodents are generally used as proxies for humans in such lab experiments.

“We now have novel targets for therapeutic intervention for a range of neurological and cardiovascular diseases, including stroke, epilepsy, dementia, hypertension, mental illness and others,” says scientist Mark S. Shapiro, PhD..

“This study should guide clinicians and pharmaceutical companies in developing new therapies against mental, neurological, cardiovascular or cerebrovascular diseases that afflict many millions of people,” the researcher goes on to say.

"Shapiro, who was the senior author of a new paper detailing the findings, holds an appointment as a professor of physiology at the Health Science Center,” Science Blog reports.

Details of the research were published in the January 7 issue of the esteemed scientific Journal of Biological Chemistry. The work details the connections the team found between phosphoinositide kinases and calcium ions.

These molecules are signaling enzymes that were evidenced to play a large role in regulating the chemical and electrical activity of rats' brains. Shapiro explains that steady calcium concentration levels are absolutely essential for the brain to work.

Another important factor is calcium transport, which also needs to operate at optimal levels at all times. If these two conditions are met, then neurobiological functions will work properly.

The conditions Shapiro mentioned tend to develop when imbalances appear in one of these two mechanisms, the research group adds. When intracellular calcium ions reached high levels, for example, epilepsy seizures appear.

What happens during such an instance is that the normal regulation patterns of neural activity breaks down, and the cortex cannot deal with this in any other way.

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Artificial Proteins Allow Living Cells to Grow

1/8/2011

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Synthetic proteins will enable researchers to create an artificial genome soon

A group of researchers from the Princeton University announces the development of the first artificial proteins, which have been proven to enable the growth of living cells in lab experiments. The groundbreaking achievement could change the face of medicine, experts believe.

What the scientists did was basically construct a number of genetic sequences that have never been identified as occurring in nature. These sequences were then showed capable of producing substances that enabled the survival of cells as if they were produced naturally.

The investigators were led by Princeton University professor of chemistry Michael Hecht, and they were able to design the artificial proteins – a world first – starting from scratch. They were expressed from artificial genes, the team adds, which is an achievement in itself.

These molecules the researchers created are bound to cause quite a stir in the area of synthetic biology, a developing field of research that holds great promise for advancing medicine and biotechnology.

“What we have here are molecular machines that function quite well within a living organism even though they were designed from scratch and expressed from artificial genes,” explains Hecht.

“This tells us that the molecular parts kit for life need not be limited to parts – genes and proteins – that already exist in nature,” the team leader adds. This type of thinking is precisely the reason why synthetic biology is getting this much attention lately.

Experts are fascinated by the possibility of designing and fabricating the biological components and systems needed to support life from scratch, as a test of their abilities, and also of their understanding of how these systems interact to underlie life.

Among the primary objectives in synthetic biology today, experts include the design and construction of an artificial genome that will include unique patterns of chemicals, not found in nature.

“Our work suggests that the construction of artificial genomes capable of sustaining cell life may be within reach,” Hecht explains, quoted by SpaceRef.

Details of the new synthetic proteins were published online in the January 4 issue of the esteemed journal Public Library of Science ONE, a peer-review scientific magazine.

“What I believe is most intriguing about our work is that the information encoded in these artificial genes is completely novel – it does not come from, nor is it significantly related to, information encoded by natural genes, and yet the end result is a living, functional microbe,” adds Michael Fisher.

“It is perhaps analogous to taking a sentence, coming up with brand new words, testing if any of our new words can take the place of any of the original words in the sentence, and finding that in some cases, the sentence retains virtually the same meaning while incorporating brand new words,” he adds.

The expert is one of the coauthors of the PLoS ONE paper. He got his PhD at Princeton in 2010, and is now a postdoctoral fellow at the University of California in Berkeley (UCB). The scientist worked with Hecht on the synthetic proteins.

The group received funds from the US National Science Foundation (NSF) for the investigation.

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Preventing HIV from Infecting Human Cells

Experts Want to Revive a Mammoth

Plant-Digesting Microbe Genomes Figured Out

Vaccines Save Lives - By Bill Gates

New Research Paths for Curing Epilepsy and Stroke Found

Artificial Proteins Allow Living Cells to Grow

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