By Riley Galton, Genetics ’14 Deoxyribonucleic acid, or DNA, encodes all of the instructions necessary for the beautiful figures and forms that can be found in the biological world. All plants, animals, and humans— subjects that are so familiar to the photographer—share the same underlying, four-letter genetic code. It is this simple molecular code that gives rise to the incredible diversity of living things, which in turn makes them so rewarding to photograph. My goal for this project was to investigate the form of the DNA itself—a form that is seldom seen, but always there. To do this, I isolated DNA from strawberries and photographed it using a macro lens.
By John Tran, Biochemistry & Molecular Biology ’14 Have you ever wanted to learn more about the plant model organism? Plants have many unique properties that make them especially important to all aspects of life. They provide oxygen, food, and energy, so you could imagine that there are many cellular and molecular processes that are involved in plants. For these reasons, we want to better understand plants using a model organism called Arabidopsis. Here, we talk about the properties of Arabidopsis and present an example of a genetic experiment, which could be used to improve the quality of apple trees. Photo credit: “Arabidopsis thaliana – Acker-Schmalwand” by Nuuuuuuuuuuul is licensed by CC BY 2.0
By Jennifer Jahncke, Psychology ’14 Something we talk about a lot in neuroscience in terms of topics like visual perception and locomotion is population vectors. A population vector is the sum of each component vector. In this image, with the trees converging to a vanishing point, the population vector would be the vector in the center of the cluster (though not quite to scale; in reality it would have a larger magnitude).
By Renata Vidovic, Evolution and Ecology ’15 To some, the phrase climate change evokes images of dry lakes, melting icebergs, and rising oceans. However, the effects of global warming are not simply cataclysmic geological changes. There are links between all biotic and abiotic features of an ecosystem. Unsurprisingly, climate change has an immense impact on frog populations around the world. Home range, abundance, breeding cycles, pathogen epidemics, and physical degradation in frogs are all affected by the changing climate.
By: Jenny Cade, Biochemistry & Molecular Biology ‘15 One of the biggest challenges in neuroscience today is mapping the wiring of the nervous system. Looking at the spatial arrangement of neural networks can tell us a lot about how information is relayed, but accurate 3D mapping of neurons is an enormously challenging task, even with the aid of computer analysis. One group of researchers at MIT has harnessed the power of crowdsourcing to tackle this problem.
By Marisa Sanchez, Molecular and Cellular Biology, ‘15 One feature that sets humans apart from other primates is the thickness of tooth enamel. Scientists at Duke University have recently discovered evidence on how evolution has resulted in thickened enamel for human teeth. By comparing the human genome to five other primate species, geneticists and evolutionary anthropologists were able to identify two segments of DNA where natural selection may have played a role in giving rise to thick enamel. Differences in enamel thickness have been linked to the difference in diet among primates. Humans consume foods that are tougher to chew relative to the food eaten by other primates, which is why humans have developed thicker enamel through natural selection.
By David Ivanov, Biochemistry and Molecular Biology, ’15 A group of researchers studying brain cells have found a new potential target for pharmacological therapies that may help treat Alzheimer’s disease. Beta amyloid plaque, which appears to be a toxic build up of fragments of amyloid precursor protein (APP) in the brain, has long been associated with Alzheimer’s disease, and has been one of the major targets for Alzheimer’s treatment. Amyloid precursor protein plays an important role in the brain, and when this protein is broken down in nerve cells the toxic byproduct beta amyloid is formed.
One of the central pursuits of modern human genetics is to move beyond genomic correlation. That is, to demonstrate experimentally why a specific genetic variant may be associated with a disease. New work in Nature Genetics from an international team lead by Philippe Froguel at Imperial College in London does just this – demonstrating an interesting link between saliva and obesity. Basically, all humans express amylase, a salivary enzyme that breaks down complex carbohydrates into absorbable sugars. The researchers found that people with more copies of the gene had a significantly decreased risk of developing obesity. People with fewer copies expressed less amylase, and it was hypothesized that this alteration in gastrointestinal carbohydrate metabolism affected insulin signaling, blood sugar levels, […]
By Mubasher Ahmed, Genetics ‘15 Viral evolution is an emerging field in biology that has great implications for human health. T7 is a phage virus, meaning it infects bacteria, and is a powerful model system in evolutionary virology. In a recent experiment, a team of biologists sought to understand the degree to which genetic elements engineered into the T7 phage genome affected the phage’s rate of propagation. In this context, the genetic elements are sequences of DNA that are inserted between genes that allow for researchers to manipulate gene regulatory networks. This allows biologists to probe how phenotypes change when gene-gene interactions are perturbed. Previous studies had shown that such genomic elements led to decreased fitness for the virus, but […]
By: Jenny Cade, Biochemistry and Molecular Biology ‘15 In a paper published in Nature Communications on April 15, researchers profiled the gut microbiota of a group of hunter-gatherers in Tanzania known as the Hadza. They compared the results to those of people living in Italy, and found that the two groups have very different species composition. The Hadza don’t only have different kinds of gut microbes than Westerners, but a more diverse collection of microbes as well. The researchers say that this is most likely due to the dramatic difference between hunter-gatherer and Western diets.