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Scientists Explain Unique Intensity & Sheen of Buttercups

Buttercup flowers are known for their intense, shiny yellow color. For over a century, biologists have sought to understand why the buttercup stands out. University of Groningen scientists have now brought together all that was known about the buttercup and added some new information too. The results will be published by the Journal of the Royal Society Interface on February 22, 2017. The article will be titled “Functional Optics of Glossy Buttercup Flowers.” The anatomy of the buttercup's petals is the first step in discovering the secret of its color. The petals have a one-cell thick epidermis, which contains a yellow pigment. Underneath this very thin cell layer is an air chamber. During his work as a Ph.D. student at the University of Groningen, Dr. Casper van der Kooi (who now works at Lausanne University, Switzerland) measured light spectra reflecting from this epidermal layer. “We discovered that this layer acts as a thin optical film. The color-generating mechanism is similar to oil on water or a soap bubble,” says Dr. Van der Kooi. “Light is reflected on both sides of the epidermis, where the cells and air meet. As the cell layer is very smooth and thin, optical interference occurs and the reflected colors merge. This creates a white sheen, which makes the petals seem glossy.” This kind of thin pigmented film is unique in the world of plants. “Butterflies use similar structures to produce color, as do some birds, but buttercups are the only known flowers to do so,” says Dr. Van der Kooi. The structure of the epidermis has been described before, but Dr. Van der Kooi and colleagues are the first to measure light spectra and conclude that the cell layer acts as a thin film.

Protein Once Thought Exclusive to Neurons Helps Aggressive Cancers Grow, Spread, Defy Death

How we think and fall in love are controlled by lightning-fast electrochemical signals across synapses, the dynamic spaces between nerve cells. Until now, nobody knew that cancer cells can repurpose tools of neuronal communication to fuel aggressive tumor growth and spread. University of Texas (UT) Southwestern Medical Center researchers report these findings in two recent studies, one in PNAS and the second in Developmental Cell. The PNAS article (online January 3, 2017) is titled “TRAIL-Death Receptor Endocytosis and Apoptosis Are Selectively Regulated by Dynamin-1 Activation,” and the Developmental Cell article (online February 6, 2017) is titled “Crosstalk Between CLCb/Dyn1-Mediated Adaptive Clathrin-Mediated Endocytosis and Epidermal Growth Factor Receptor Signaling Increases Metastasis.” “Many properties of aggressive cancer growth are driven by altered cell signaling,” said Dr. Sandra Schmid, senior author of both papers and Chair of Cell Biology at UT Southwestern. “We found that cancer cells are taking a page from the neuron’s signaling playbook to maintain certain beneficial signals and to squelch signals that would harm the cancer cells.” The two studies find that dynamin1 (Dyn1) – a protein once thought to be present only in nerve cells of the brain and spinal cord – is also found in aggressive cancer cells. In nerve cells, or neurons, Dyn1 helps sustain neural transmission by causing rapid endocytosis – the uptake of signaling molecules and receptors into the cell – and their recycling back to the cell surface. These processes ensure that the neurons keep healthy supplies at the ready to refire in rapid succession and also help to amplify or suppress important nerve signals as necessary, Dr. Schmid explained. “This role is what the cancer cells have figured out.

First Controllable Electronic Switch Within Single DNA Molecule

DNA, the stuff of life, may very well also pack quite the jolt for engineers trying to advance the development of tiny, low-cost electronic devices. Much like flipping your light switch at home---only on a scale 1,000 times smaller than that of a human hair---an Arizona Statte University (ASU)-led team has now developed the first controllable DNA switch to regulate the flow of electricity within a single, atomic-sized molecule. The new study, led by ASU Biodesign Institute researcher Dr. Nongjian Tao, was published online on February 20, 2017 in Nature Communications. The open-access article is titled “Gate-Controlled Conductance Switching in DNA.” "It has been established that charge transport is possible in DNA, but for a useful device, one wants to be able to turn the charge transport on and off. We achieved this goal by chemically modifying DNA," said Dr. Tao, who directs the Biodesign Center for Bioelectronics and Biosensors and is a professor in the Fulton Schools of Engineering. "Not only that, but we can also adapt the modified DNA as a probe to measure reactions at the single-molecule level. This provides a unique way for studying important reactions implicated in disease, or photosynthesis reactions for novel renewable energy applications." Engineers often think of electricity like water, and the research team's new DNA switch acts to control the flow of electrons on and off, just like water coming out of a faucet. Previously, Dr. Tao's research group had made several discoveries to understand and manipulate DNA to more finely tune the flow of electricity through it.

Estrogen Explains Exosome-Carried Messenger Profile in Circulation Among Postmenopausal Women

A study at the Gerontology Research Center at University of Jyväskylä in Finland has demonstrated that, in blood circulation, the exosome-carried messenger molecule profile differs between post- and premenopausal women. The differences were associated with circulating estrogen and cholesterol levels, as well as body composition and other health indicators. These findings enable using the studied molecules in the evaluation of health status. The studied messenger molecules are packed in the exosomes, which are released by the cells into the circulation. Exosomes are spherical nanoscale lipid vesicles. These small packages carry microRNA molecules, among other molecules, which are considered to be messengers between the cells regulating gene function, says Docent Eija Laakkonen. The study was the first to show that specific exosome-packed microRNAs are sensitive to the estrogen levels in the circulation, which are influenced both by age and the use of hormonal therapies. The results can be exploited in evaluating the effects of hormonal contraceptives and hormone replacement therapies on the overall physiological status of women. When the regulatory mechanisms of the microRNAs are better understood, the microRNA profile can be used for recognizing individuals with a high risk for metabolic disorders, or even lowering the risk. It seems, therefore, that the postmenopausal declining amount of circulating estrogen changes the cargo inside the exosomes. When these exosome packages are delivered to the target tissues, the contents are released to the correct recipient cell. These delivered messages change the function of the cell, explains doctoral candidate Reeta Kangas.

Synthetic Compound Developed at Moscow State University Slows Down Aging of Mice with Mutated Mitochondria

A group of Russian and Swedish scientists has recently published a breakthrough paper, reporting results of a joint study by Lomonosov Moscow State University and Stockholm university. The article was published in the U.S. journal Aging. The major goal of the study was to investigate the role of intracellular powerstations -- mitochondria -- in the process of aging of organisms. Importantly, scientists made an attempt to slow down aging using a novel compound: artificial antioxidant SkQ1 precisely targeted into mitochondria. This compound was developed at the Moscow State University by the most cited Russian biologist Professor Vladimir Skulachev. Experiments involved a special strain of genetically-modified mice created and characterized in Sweden. A single mutation was introduced into the genome of these mice resulting in the substantially accelerated mutagenesis in mitochondria. This leads to accelerated agiing and early death of the mutant mice. They live less than 1 year (normal mouse lives more than 2 years). The mutation promotes development of many age-related defects and diseases indicating that the major defect of these mice is indeed aging. Starting from the age of 100 days one group of mutant mice was treated with small doses of SkQ1 (approxamtely 12 micrograms) added into their drinking water. Per scientists' hypothesis, the compound must protect animal cells from the toxic byproducts of mitochondria -- free radicals (reactive oxygen species). Another group of animals served as a control group receiving pure water. Differences between the two groups became obvious starting from the age 200-250 days. Animals in the control group aged rapidly as expected.

Gene Editing Can Complement Traditional Food-Animal Improvements

Gene editing -- one of the newest and most promising tools of biotechnology -- enables animal breeders to make beneficial genetic changes, without bringing along unwanted genetic changes. And, following in the footsteps of traditional breeding, gene editing has tremendous potential to boost the sustainability of livestock production, while also enhancing food-animal health and welfare, argues University of California (UC) Davis animal scientist Dr. Alison Van Eenennaam. She examined the potential benefits of genome editing on Friday, February 17, 2017 at the annual meeting of the American Association for the Advancement of Science, to be held in Boston's Hynes Convention Center. Her presentation was part of a 3 p.m. EST session titled "The Potential of Gene Editing to Revolutionize Agriculture," moderated by acclaimed molecular biologist Dr. Nina Federoff. Dr. Van Eenennaam was also scheduled to participate in a news briefing on this topic at noon EST on Saturday, February 18, 2017 in Room 103 of the convention center. Thanks to improvements made in the dairy industry through traditional breeding, a glass of milk today is associated with just one third of the greenhouse gas emissions linked to producing a glass of milk in the 1940s, says Dr. Van Eenennaam, a UC Cooperative Extension biotechnology specialist in the UC Davis Department of Animal Science. That was accomplished as traditional selective breeding improved the productivity of dairy cows so much that the number of dairy cows in the United States dropped from a high of 25.6 million in 1944 to about 9 million today, even as the country experienced a 1.6-fold increase in total milk production, she says.

Capricor to Focus on Advancing Cardiac Cell and Exsosome-Based Therapeutic Candidates

On February 16, 2017, Capricor Therapeutics, Inc. (NASDAQ: CAPR), a clinical-stage biotechnology company developing first-in-class biological therapies for cardiac and other medical conditions, announced that it has elected to terminate its license agreement with the Mayo Clinic relating to natriuretic peptide receptor agonists, including Cenderitide. "Our decision to return these rights is a strategic move as we prioritize our efforts to advance our core cell and exosome-based therapeutic development programs," said Dr. Linda Marbán, Ph.D., President and Chief Executive Officer. "We enter 2017 with the anticipation of several key events to occur this year. These include our expected announcement early next quarter of top-line results of our randomized Phase I/II HOPE clinical trial of CAP-1002 (allogeneic cardiosphere-derived cells) in people with Duchenne muscular dystrophy (DMD)-associated heart disease, as well our expectation to clinically evaluate CAP-1002 for its ability to improve peripheral and respiratory muscle in DMD in a trial that is currently being planned. We are also committing increased attention to our exosomes program, and we expect to file an Investigation New Drug application for CAP-2003 (cardiosphere-derived cell exosomes) in the second half of this year," added Dr. Marbán. Capricor Therapeutics (formerly Nile Therapeutics, Inc.) entered into an Amended and Restated Technology License Agreement in 2013 around the time of the corporate merger. Since that time, Capricor has completed two small Phase II studies of Cenderitide, also known as CD-NP, in subjects with chronic, stable heart failure. Capricor Therapeutics, Inc.

Yeast Found in Babies’ Guts Increases Risk of Asthma

University of British Columbia (UBC) microbiologists have found a yeast in the gut of new babies in Ecuador that appears to be a strong predictor that they will develop asthma in childhood. The new research furthers our understanding of the role microscopic organisms play in our overall health. "Children with this type of yeast called Pichia were much more at risk of asthma," said Dr. Brett Finlay, a microbiologist at UBC. "This is the first time anyone has shown any kind of association between yeast and asthma." In previous research, Dr. Finlay and his colleagues identified four gut bacteria in Canadian children that, if present in the first 100 days of life, seem to prevent asthma. In a follow-up to this study, DR. Finlay and his colleagues repeated the experiment using fecal samples and health information from 100 children in a rural village in Ecuador. Canada and Ecuador both have high rates of asthma with about 10 per cent of the population suffering from the disease. The scientists found that while gut bacteria play a role in preventing asthma in Ecuador, it was the presence of a microscopic fungus or yeast known as Pichia that was more strongly linked to asthma. Instead of helping to prevent asthma, however, the presence of Pichia in those early days puts children at risk. Dr. Finlay also suggests there could be a link between the risk of asthma and the cleanliness of the environment for Ecuadorian children. As part of the study, the researchers noted whether children had access to clean water. "Those that had access to good, clean water had much higher asthma rates and we think it is because they were deprived of the beneficial microbes," said Dr. Finlay. "That was a surprise because we tend to think that clean is good, but we realize that we actually need some dirt in the world to help protect you." Now Dr.

Gene Sequences Reveal Secrets of Symbiosis

Advances in genomic research are helping scientists to reveal how corals and algae cooperate to combat environmental stresses. King Abdullah University of Science & Technology (KAUST) researchers have sequenced and compared the genomes of three strains of Symbiodinium, a member of the dinoflagellate algae family, to show their genomes have several features that promote a prosperous symbiotic relationship with corals. The article was published online on December 22, 2016 in Scienctific Reports. The open-access article is titled “Genomes of Dinoflagellate Symbionts Highlight Evolutionary Adaptations Conducive to a Symbiotic Lifestyle.” Dinoflagellates are among the most prolific organisms on the planet, forming the basis of the oceanic food chain, and their close symbiotic relationships with corals help maintain healthy reefs. However, because dinoflagellates have unusually large genomes, very few species have been sequenced, leaving the exact nature of their symbiosis with corals elusive. "We had access to two Symbiodinium genomes, S.minutum and S.kawagutii, and we decided to sequence a third, S. microadriaticum," said Assistant Professor of Marine Science Dr. Manuel Aranda at the University's Red Sea Research Center, who led the project with his Center colleague Associate Professor of Marine Science Dr. Christian Voolstra and colleagues from the University's Computational Bioscience Research Center and Environmental Epigenetics Program. "This allowed us to compare the three genomes for common and disparate features and functions and hopefully to show how the species evolved to become symbionts to specific corals."

Powerful Optical Imaging Technology (SICLON) Resolves Natural Fluorescence of DNA

Many of the secrets of cancer and other diseases lie in the cell's nucleus. But getting way down to that level -- to see and investigate the important genetic material housed there -- requires creative thinking and extremely powerful imaging techniques. Dr. Vadim Backman and Dr. Hao Zhang, nanoscale imaging experts at Northwestern University, have developed a new imaging technology that is the first to see DNA "blink," or fluoresce. The tool enables the researchers to study individual biomolecules as well as important global patterns of gene expression, which could yield insights into cancer. Dr. Backman was to discuss the tool and its applications -- including the new concept of macrogenomics, a technology that aims to regulate the global patterns of gene expression without gene editing – on Friday (February 17, 2017) at the American Association for the Advancement of Science (AAAS) annual meeting in Boston. The talk, entitled "Label-Free Super-Resolution Imaging of Chromatin Structure and Dynamics," is part of the symposium "Optical Nanoscale Imaging: Unraveling the Chromatin Structure-Function Relationship," which was to be held from 1 to 2:30 p.m. Eastern Time February 17 in Room 206, Hynes Convention Center. The Northwestern tool features six-nanometer resolution and is the first to break the 10-nanometer resolution threshold. It tool image DNA, chromatin, and proteins in cells in their native states, without the need for labels. For decades, textbooks have stated that macromolecules within living cells, such as DNA, RNA and proteins, do not have visible fluorescence on their own. "People have overlooked this natural effect because they didn't question conventional wisdom," said Dr. Backman, the Walter Dill Professor of Biomedical Engineering in the McCormick School of Engineering at Northwestern.

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