Today is the last day to apply for a travel award to get to this neuroscience celebration! Details here.

It’s reunion time for the MBL SPINES course, with a day-long symposium planned for this fall in Chicago. Held a day before the annual Society for Neuroscience meeting, the symposium will be a chance to catch up with friends, network, attend presentations, and celebrate the community the SPINES course has created.

The Summer Program in Neuroscience, Ethics, & Survival (SPINES) is an intense, month-long program held each summer at the MBL since 1995. It integrates training in lab techniques, grant writing, ethics, and public speaking, among other skills essential for early-career scientists. The course is also a networking opportunity and a way to build community for underrepresented groups in science, the target audience for the course. This symposium will celebrate the achievements of alumni students and faculty and expand the SPINES network across years and career stages to promote networking and collaboration.

The symposium will be held on October 16th, 2015 at the University of Chicago, and there is still time to apply for a travel award to help get there. More information can be found here, and details on the travel grant can be found here. Please contact Chinonye Nnakwe, Ph.D., at spinessymposium(@)gmail.com with questions.

SPINES students hard at work in the lab. Photo credit: Tim Kleindinst

SPINES students hard at work in the lab. Photo credit: Tim Kleindinst

Call this the Age of the Microbiome. Just a few short years ago, in 2012, the first “map” of the microbial species that live on and in the human body was published. Today, the data just keep coming that reveal the myriad connections between a person’s health—or an organism’s behavior—and the status of his, her or its microbiome, with correlations found in traits ranging from obesity to autism to ulcerative colitis.

One of the researchers at the forefront of microbiome research is Jack Gilbert, group leader for Microbial Ecology at Argonne National Laboratory and Associate Professor at the University of Chicago, as well as a faculty member at MBL. Catch up with Gilbert and the latest frontiers in microbiome research here, in a detailed profile in this month’s issue of The University of Chicago Magazine.

Bacteria-forming-a-mixed-biofilm-on-colon-cancer-tissue.-Credit-Jessica-Mark-Welch,-Blair-Rossetti,-and-Christine-Dejea, MBL

Bacteria forming a mixed biofilm on colon cancer tissue. Credit Jessica Mark Welch, Blair Rossetti, and Christine-Dejea, MBL

By Kelsey Calhoun

Vision has been studied inside and out for more than a century, resulting in some textbooks presenting the visual system as essentially understood. But María Gomez and Enrico Nasi, adjunct scientists at the Marine Biological Laboratory (MBL), don’t agree. They have spent the last several years investigating non-visual photoreceptors, cells whose function remains elusive in eyes filled with rods and cones. They reveal an important clue to how these cells work—how calcium triggers the electrical light response— in a recent paper published in Proceedings of the National Academy of Sciences.

Enrico Nasi and Maria del Pilar Gomez

Enrico Nasi and Maria del Pilar Gomez

Studies of vision traditionally divided light-sensitive cells into two distinct classes: those of vertebrates and those of invertebrates. The two classes were so different from each other that they were thought to represent two separate lines of evolution. But a few phenomena presented problems with this view. The most dramatic is the fact that blind people, who lack functioning rods and cones—the only photoreceptive cells previously thought to exist in vertebrates—can recover from jet lag, somehow sensing the light that resets their circadian rhythms. “A new type of photosensitive cell was later discovered in the mammalian eye that is responsible for these functions,” says Nasi. “Another dogma bites the dust.”

It is these non-visual photoreceptors, sometimes called circadian photoreceptors, that Nasi and Gomez, both professors at the Universidad Nacional de Colombia, were interested in studying. “What are these sensors? The idea that they might be just like photoreceptors of invertebrates—this is beyond blasphemy,” says Nasi. If true, “this leads to rewriting the evolutionary history of vision.” But studying these cells presented a few practical challenges. In vertebrates, the cells are few and far between, and have no unique shapes or markers to make them easy to find.

Amphioxus can grow as long as 2.5 inches, and it is very difficult to tell their head from their tail. Other than that, they are a very useful animal model. Photo by Hans Hillewaert.

Amphioxus can grow as long as 2.5 inches, and it can be difficult to tell the head from the tail. Photo by Hans Hillewaert

So Gomez and Nasi turned to an unassuming, fish-like invertebrate called a lancelet or amphioxus. This creature holds a unique place on the evolutionary tree of life, at the branching point between vertebrates and invertebrates. It has other advantages: the photoreceptors that interest Gomez and Nasi are easy to find in the organism, and manipulate. The evidence they found in the simple amphioxus suggests that vertebrates’ non-visual photoreceptors may mimic those found in amphioxus—that the visual systems of vertebrates and invertebrates are not as different as previously thought.

Their paper tackles the final step of the pathway that lets these photoreceptors translate incoming light into signals to the organism. Most of the pathway was already known, but solid evidence for the last step was elusive: How was light converted to an electrical cell signal that could be communicated to other cells?

Gomez and Nasi investigated the flood of calcium that is released when the circadian photoreceptors were exposed to light. They showed that calcium provoked the electrical cell signal, very similar to what happens with normal light stimulation. “It reproduces the native response,” says Gomez. This flood of calcium is the link that lets these photoreceptors communicate with the rest of the organism.

“We’re rather happy to see something that fully reproduces the light response for the first time,” Nasi says. But, he adds, “We don’t want to make claims that this is going to be general to all species.” Whether this discovery proves to be common in other species or not, it’s clear the field of vision and light-sensing cells still has much to reveal.

Citation:
Peinado G, Orsano T, Gomez M, and Nasi E (2015). Calcium activates the light-dependent conductance in melanopsin-expressing photoreceptors in amphioxus. PNAS, DOI: 10.1073/pnas.1420265112

By Rachel Buhler

Two journalists who received fellowships from the MBL Logan Science Journalism Program are spending the next week with scientists pursuing environmental field research at Toolik Field Station in Arctic Alaska, including studies of global climate change.

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Michael Werner and Meera Subramanian at the Arctic Circle, 150 miles north of Fairbanks.

The two fellows, freelance journalist Meera Subramanian and freelance journalist/ filmmaker Michael Werner, both attended the program’s hands-on course at the MBL in June, undertaking field and laboratory research to “step into the shows of the scientists they cover.”  Last Tuesday, they flew into Fairbanks, Alaska, as the starting point for their journey to Toolik, which entails a minimum eight-hour drive and a passage across the Arctic Circle.

Subramanian has been blogging  — with striking photos and videos of the Arctic tundra and its scientist inhabitants — on the program’s blog, “A Toolik Field Journal.”

Over the years, the Logan Science Journalism Program has granted fellowships to hundreds of journalists from prominent news organizations, including The New York Times, The Wall Street Journal, Science, National Public Radio, The Washington Post, USA Today, CNN, and Scientific American. Journalists from Africa, Brazil, Sweden, India, Japan, the United Kingdom and other countries have also received fellowships.

One of the largely unexplored habitats on Earth lies under the ocean: the sediments, rocks, and fluids layered under the pressure of a gigantic basin of water. What lives down there, and how deep does life go? What strategies do microbes have for surviving in this environment? MBL Associate Scientist Julie Huber is among the people asking these questions, and this week she contributes a commentary in the journal Science on a team’s discovery of the deepest subseafloor life yet.

Julie Huber. Credit: Diana Kenney

Julie Huber. Credit: Diana Kenney

Using a drilling system aboard a research vessel off the Shimokita Peninsula of Japan, the international team “drilled the deepest scientific borehole to date to examine the abundance, taxonomic composition, and biosignatures of subseafloor microbial communities in sediments from 400 to almost 2,500 meters (about 1.5 miles) beneath the seafloor,” Huber writes. They detected microbial life at all depths, including methane-producing archaea in deeply buried coal-bed deposits.

As expected from prior studies, the concentration of microbes decreased steadily with depth in the shallow subseafloor layers. However, microbes were scarce–barely detectable—below about 1,500 meters. This was surprising, given that temperatures in the deep samples didn’t exceed ~60 degrees C, “well within the growth range of most microbes,” and “both carbon and hydrogen are plentiful energy sources, particularly in the coal bed layers,” Huber writes.

“Why so little life, then?” Huber writes. “It is difficulties with biomolecule repair, as the authors suggest, or something else like porosity or pressure? Uncovering what limits the biomass in this unusual environment will certainly be a focus of future studies.”

Huber is associate director of the MBL’s Josephine Bay Paul Center, as well as associate director of the NSF Science and Technology Center for Dark Energy Biosphere Investigations (C-DEBI).

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Huber JA (2015) Making methane down deep. Science 349: 376-377.

Inagaki F et al (2015) Exploring deep microbial life in coal-bearing sediment down to ~2.5 km below the ocean floor. Science 349: 420-424.

Article in The Washington Post quoting Huber on Inagaki et al.

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