Archive for June, 2011

By Beth Liles

The MBL hosted a meet-and-greet barbeque on the Swope Terrace for 23 undergraduates who will spend the summer up to their elbows in research in Woods Hole. Swapping stories around the picnic tables were 13 students in the Partnership in Education Program (PEP) and 10 in the Biological Discovery in Woods Hole/REU program.

PEP and BDWH students, standing, from left: Jacob Cravens (Boston College), Norian Caporale-Berkowitz (Brown University), Rachel Noyes (Ithaca College), Miles Borgen (Western Washington University), Morgan Kelly (Harvard University). Seated, from left: Kari Jackson (Morehouse College), Matt Birk (UNC Wilmington), Michelle Frank (St. Olaf), Emma Tran (University of Texas)

The Biological Diversity in Woods Hole program is a Research Experiences for Undergraduates initiative funded by the National Science Foundation.

PEP is a partnership between the Woods Hole Diversity Initiative (whose members include MBL, NOAA/National Marine Fisheries Service, Woods Hole Oceanographic Institution, USGS Woods Hole Science Center, SEA Education Association, and Woods Hole Research Center) and the University of Maryland Eastern Shore.

Front table, clockwise from lower left: Stephani Fogerson (William Jewel College), Cloe Howard (Spelman College), Andrew Klein (University of Maryland, College Park), Dr. Ambrose Jearld (PEP director; NOAA/NMFS), Joel Ramkhelawan (Universidad del Este, Puerto Rico), Jesse Diaz (UPR Cayey), Onjale Scott (PEP coordinator), Janeea Ventour (Tuskegee University)

Clockwise from lower left: Ann Thompson (Humboldt State University), Lakiah Clark (Tuskegee University), Jan-Alexis Barry (University of the Virgin Islands), James Lewis (University of Maryland, College Park), Al Mensinger (BDWH/REU program co-director; University of Minnesota, Duluth), Cassandra Ruff (Humboldt State University), Jamie Medina (Bridgewater State College), Katie Laushman (Earlham College), Alicia Perez (Humboldt State University)

From left: Allen Mensinger (BDWH/REU director; University of Minnesota, Duluth); George Liles (PEP program manager; NOAA/NMFS); R. Paul Malchow (BDWH/REU director; University of Illinois at Chicago); Ambrose Jearld (PEP director; NOAA/NMFS)

By Amanda Rose Martinez

Venture into the Grass Lab this summer on the second floor of Rowe and you’re liable to hear the amorous calls of singing fish.

This week, Liz Whitchurch, a 2011 Grass Fellow who hails from the University of Washington, was busy building the fictitious nests she’ll use to study the auditory behavior of plainfin midshipman, a type of fish that sings to attract its mates.

Grass Fellow Liz Whitchurch is building fictitious nests for her study species, the plainfin midshipman. Photo by Amanda R. Martinez

Whitchurch sets the scene. On spring nights all along the West Coast, randy, male midshipman flood the intertidal zone. They rapidly contract a muscle on their swim bladder, which results in a low, resonant hum that lady midshipman find irresistible.

“They’re calling to the females: ‘Come lay your eggs in my nest,’ ” says Whitchurch. “And the females, out there somewhere in the water, then have the task of localizing that call.” They zero in on the male whose call is most alluring and lay their eggs in his nest. The male then cares for the eggs for the rest of the summer. All told, not a bad deal.

Whitchurch will use a micro-electrode as thin as a strand of hair to measure the midshipman's response to mating calls. Photo by Amanda R. Martinez

“These fish are really interesting because they rely entirely on their auditory sense to reproduce,” Whitchurch explains. But while scientists have observed how the midshipman’s brain encodes sound underwater, to date, studies have only looked at immobilized fish.

“The whole idea is to understand how auditory cues are encoded in the brain while these fish are actually swimming around,” says Whitchurch, who plans to measure the phenomenon for the first time by monitoring midshipman in a six-foot-diameter tank in the MBL’s Marine Resources Center. “If you understand how fish navigate using sound, you can imagine building machines that navigate in the same way,” she says.

In a lab upstairs, Grass Fellow Raquel Vasconcelos, from the University of Lisbon, is investigating the behavior of a different singing fish—the toadfish. Emitting sounds that conjure a boat horn, male toadfish also depend on vocalizations to woo their would-be mates.

Raquel Vasconcelos prepares an electrode to measure the response of a Lusitanian toadfish to minute sound vibrations. Photo by Amanda R. Martinez

Hunched over a machine designed to mimic minute sound vibrations that occur in the ocean, Vasconcelos prepares to insert an electrode into the nerve of an anesthetized toadfish, staged on the machine’s surface. Richard Fay, an expert on fish hearing and a summer fixture at MBL since 1993, lends a hand.

“We think that the fish ear is stimulated not by sound pressure, as in human hearing, but by the motion of sound particles,” explains Fay. In the natural environment, when sound passes through the fish, it moves in the direction of that sound.

Richard Fay of Loyola University Chicago adjusts the accelerometer of a machine designed to mimic nanoscale sound vibrations that occur in the ocean. Photo by Amanda R. Martinez

In studying how toadfish nerves respond to sound vibrations, Vasconcelos hopes to better understand how the fish ear processes auditory feedback or background noise in the water, and how such feedback may affect the toadfish’s vocal, and thus, mating behavior. “There’ve been a lot of studies about auditory feedback in birds,” Vasconcelos said, “but as far as I know this would be the first that looked at fish.”

“Firsts” and other research innovations are an enduring theme at the Grass Lab, which for 14 weeks every summer since 1952 has served as an oasis for burgeoning leaders in the field of neuroscience. It’s an oasis in the sense that it affords its fellows the chance to fiercely pursue their research goals, while in the company of distinguished peers, using state-of-the-art equipment, and with little threat of distraction.

Felix Schweizer shows the Grass Lab's original door, a relic saved from the lab's former location in Lillie. Photo by Amanda R. Martinez

“What distinguishes it from their home labs,” says Felix Schweizer, a ‘94 Grass Fellow who currently serves as the Lab’s co-director, “is that the preparations they’re working on are all very different, which is exciting, right? Most of these preparations are things that we’ve heard about, like the toadfish. But in my lab, for instance, you would never see a toadfish. And then you come here and you see all of these classic things going on—people who do molecular work or maybe more biophysical work. And then suddenly they’ll hear something about animal behavior that they never really thought about.”

It’s this exposure to diverse disciplines that can profoundly impact the way that Grass Fellows think about their work. The result is often original perspectives and novel research methods that have bequeathed the Grass Lab its reputation for creativity. “It’s a very unique environment to do science in,” Schweizer says.

To apply for a Grass Fellowship, please visit: www.grassfoundation.org. Application deadline is December 5th.

Felix Schweizer expresses the Grass Lab's vibrant legacy. In the background, a portrait shows electrical engineer Albert Grass, who, along with his wife, Ellen, established the Grass Foundation in 1955. Photo by Amanda R. Martinez

By Amanda Rose Martinez

Students in this year’s Embryology course have just six weeks to wrap their heads around a, if not the, fundamental question of biology: How do you start with a single egg and get to a full embryo? As it turns out, explained Nicole King in Tuesday’s lecture on “Animal Origins,” this is also a fundamental question of evolutionary biology: How did multicellular animals evolve from their single-celled ancestors?

“Our goal,” said King, an associate professor of genetics, genomics, and development from the University of California, Berkeley, “is to try and identify genomic and cell biological innovations that might have contributed to this transition.” She then unveiled the two key players that may prove pivotal in helping scientists to uncover such innovations— choanoflagellates and sponges.

Choanoflagellate: evolution's last stop on the way to animals. Photo by Mark Davel

Choanoflagellates have a spherical cell body, bordered at its crown by a collar of minute, hair-like projections, and a long, central appendage called a flagellum that resembles a whip and enables it to swim. King’s allowance that “it’s reasonable to think of these organisms as sperm cells with a collar,” sent a ripple of early-morning snickers through the auditorium. But what’s special about the unicellular choanoflagellates is that they’re the closest living relatives of animals. Just next to the choanoflagellates on an evolutionary chart lies the multicellular sponges, the earliest branching lineage of animals.

A sponge named Oscarella carmela. Photo by Scott Nichols

In this way, choanoflagellates and sponges “bracket the evolution of multicellularity,” said King. “If we can study these organisms at the molecular level, see what they share in common, see what’s different, hopefully someday, we’ll be able to reconstruct the molecular processes that contributed to the origin of animals.”

Later in the Lab…

Tuesday afternoon, the students got their first glimpse of choanoflagellate and sponge cells. Using a standard imaging technique, they added a fluorescent antibody to a structural protein (beta-tubulin) that is common to both organisms. When viewed under a microscope, the antibodies could be seen fluorescing bright green, which served to highlight the outline of each cell body and flagellum, but also emphasized the shared architecture between choanoflagellate and sponge cells.

“The hope is that these students have interests that are unique and eclectic, and that they’ll take these techniques and apply them in novel ways for their areas of interest,” said Stephen Fairclough, a graduate student in King’s lab at UC Berkeley and one of the teaching assistants for this year’s course.

 

Yi-Ju Chen (R) of Caltech gets advice on sample preparation from Embryology faculty member Nicole King (L). Photo by Amanda R. Martinez

Eclectic interests indeed. A quick canvas of the room revealed Yi-Ju Chen, a graduate student in physics from Caltech interested in evolutionary theory and pattern formation; Valerie Virta, a postdoc at the National Institute of Child Health and Human Development (NICHD), who is investigating the mechanism that causes some cells to stop moving and become the bones that form the face; and Joseph Campanale, a PhD student at the Scripps Institution of Oceanography, who studies how embryos eliminate or detoxify environmental chemicals during development.

Joseph Campanale of Scripps readies a piece of sponge for viewing under a microscope. Photo by Amanda R. Martinez

Valerie Virta of NICHD prepares humidification chambers for her samples. Photo by Amanda R. Martinez

By Amanda Rose Martinez

The Neural Systems and Behavior course (NS&B) was already humming with activity last week as it prepared to kick off its 33rd year. Setting up equipment in Loeb Laboratory on Wednesday was a group of the course’s seasoned regulars, including faculty Lidia Szczupak and Ron Calabrese and teaching assistant Michael Wright.

His eyes glued to a small, circular level, Wright, who is in his fourth year with the course, meticulously adjusted the legs of what could be called the pièce de résistance of the NS&B’s lab equipment: the floating air table.

Michael Wright (L) of Emory University and Herb Luther of MBL Education precision the alignment of an air table in the NS&B lab. Photo by Amanda Martinez

“Very minute vibrations on a preparation that has two electrodes on neurons can just be the end of the experiment,” says Szczupak, who is from the Universidad de Buenos Aires and is marking her 11th summer with NS&B.

Photo by Amanda Martinez

To create a flawlessly stable surface, each table is covered with a metal plate that rests on top of a pocket of air. Everything—microscopes, cells, electrodes, micromanipulators—is affixed to the plate through a series of metal holes on its surface. This way, any vibrations from the footsteps of people walking around or a slammed door are evenly distributed throughout the sensitive experiment’s components.

Come 9 AM Monday this week, 20 students from around the world began the first of four two-week cycles, each of which explores the neural system of a different animal. First up is the leech, which, with its simple nervous system and neurons that are easily recognized with a microscope, is an ideal starting organism.

Lidia Szczupak. Photo by Amanda Martinez

“The goal is to get the kids to approach live neurons with their own hands,” says Szczupak. Come back in two days, she says, and “you’ll see people who never worked with a single neuron before. They’ll be familiar with putting electrodes in the cells, recording resting potential, action potential, and learning what this means.”

If there’s one event in this cycle that NS&B faculty are eagerly anticipating, it’s an appearance by John Nicholls, “one of the ‘Fathers of the Leech,’ ” as Szczupak calls him. Nicholls, formerly of SISSA in Italy and lately teaching in countries around the world, will give a talk on the significance of the leech in neurophysiology research. No stranger to NS&B, Nicholls can be identified among the instructors in the course’s earliest class photos, which are posted in the hall outside the lab.

John Nicholls is 3rd row, 2nd from right (sleeves rolled up) in the 1979 NS&B class photo.

Veteran NS&B faculty member Ron Calabrese. Photo by Amanda Martinez

But when asked what they’re most looking forward to and consequently, the thing that keeps them coming back year after year, NS&B faculty unanimously cited two things—camaraderie and friendships, old and new. “It’s just a lot of fun,” says Ron Calabrese of Emory University, who joined the course as a TA in 1979 and has been back every year since. “I like meeting people. I like seeing what they’re about.”

“We’ve been on the same team with minor differences for ten years,” Szczupak says. “We became friends and it’s very nice to be together doing this.”

Photo by Pam Wilmot

Hot weather appeared abruptly in Woods Hole this week, and along with it came a flock of early birds. With radios playing and adrenaline pumping, faculty and teaching assistants in Loeb Laboratory began unpacking crates of lab equipment, hooking it up, testing it out, and making sure all systems are go before the first MBL summer courses begin on Monday. There have also been sightings of early-arriving Whitman Investigators in Rowe Laboratory.
 
A warm welcome back to the MBL!