 |
|
|
|
|
|
|
|
|
|
|
 |
|
|
 Marine Animals
|
|
|
 |
|
|
|
|
|
|
 |
|
|
 |
|
|
|
Clams and Cancer
 With transparent eggs and embryos, clams are uniquely suited for studies of cell division. As clam eggs develop, they offer biologists a clear view of the processes that enable a single cell to give rise to a complete organism— processes common to clams, cobras, and cab drivers.
In the early 1980s, MBL researchers Joan Ruderman and Tim Hunt discovered a previously unknown protein in fertilized clam eggs. Interestingly, the protein accumulated and then disappeared as cells prepared to divide and then divided. The protein, dubbed cyclin, turned out to be a regulator of cell division.
This major discovery was made during lab work for one of the summer courses, with students on hand to take part in the excitement of "breaking" science. Further work by Ruderman and others revealed that some cancer cells produce too much of a particular kind of cyclin at the wrong time, causing cells to divide inappropriately and contributing to cancer. Today, physicians are exploring the use of cyclins for early diagnosis of breast cancer.
|
|
 |
|
|
| The surf clam is helping biologists clear up long-standing mysteries about how cells divide, leading to potential new cancer therapies for humans. |
|
Squid and Neurological Disorders
Nerves are the highways of action, a fantastically complex network that carries information about the external world and our reactions to it. Endowed with a stunningly large nerve cell (or axon), the Woods Hole squid has contributed so much to the study of nerve structure and function that one biologist has suggested the animal should receive a Nobel Prize.
Big enough to be seen with the unaided eye (and mistaken by early biologists for a blood vessel), the squid's famous "giant axon" is one of the most thoroughly studied cells on earth. Three generations of MBL researchers have used the giant axon to shed light on most of the puzzles in neuroscience, including the mechanisms that underpin human consciousness.
Nerve cells, the stuff of spinal cords and brains, are so wondrously complicated that 60 years of research have not begun to exhaust the lessons the axon can teach. Today investigators come to Woods Hole from Argentina and Connecticut, Germany and Texas, looking to the axon for clues to diseases such as Alzheimer's disease, multiple sclerosis, and Lou Gehrig's disease.
|
|
|
|
 |
|
|
The axons, or long nerve fibers, of the Woods Hole squid (above) are unusually large and therefore easily studied by scientists seeking clues to a variety of diseases affecting the human nervous system. |
|
|
|
Toadfish and Balance
Probably only two creatures on Earth find a toadfish beautiful—another toadfish and a biologist. The fish's broad, flat head gives it the alarming look of an enormous polliwog. That shape, however, also accounts for the animal's unique nerve wiring, which in turn helps account for Steve Highstein's 20-year interest in toadfish.
The nerves leading to and from the toadfish brain are easy to sort out, with few of the intertwining's common to other creatures (like humans) who must cram their nerves through relatively small openings in the skull.
Our vestibular (or balance) system relies on fluid filled canals in the ear that tell us which end is up. The toadfish's vestibular system is similar enough to ours to make comparisons meaningful, but the nerve layout of the fish is easier to explore. Research by Highstein and others may point the way to improved therapies for motion sickness, Meniere's Disease and other balance disorders, and some hearing impairments.
|
|
 |
|
|
| For decades biologists have come to the MBL to study the toadfish (above). One or another aspect of its anatomy makes it a good model for research into insulin secretion and diabetes, hearing, and dizziness, and nausea and motion sickness. |
|
Horseshoe Crabs and Vision
 A contemporary of the dinosaurs, the horseshoe crab is so successful that it has changed little in several hundred million years. One of the animal's successful adaptations is its eye, a relatively simple organ that nonetheless functions well in a range of lighting intensities that vary by a factor of one million.
MBL researchers have been studying the horseshoe crab's eyes for decades, in the process uncovering a large part of what is known about the molecular and cellular basis of human vision. It was in the horseshoe crab's eye, for instance, that MBL researcher Keffer Hartline discovered the mechanisms of "lateral inhibition," a processing strategy in which retinas enhance light signals to trick the brain into seeing sharper borders and edges. Hartline won the 1967 Nobel Prize for his vision research.
Today, Hartline's last student, Robert Barlow, is using computer models of eyes and brains to process data gathered from horseshoe crab eyes. He is attempting to break the neural code for visual signals, a feat that could help explain and possibly point the way to treatments for human visual disorders.
|
|
|
|
 |
|
|
| The light-sensitive cells of the horsecrab's lateral eyes are large enough to be seen with the naked eye and number only about 1000 as compared with more than 150 millions rods and cones found in the human eye. |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| |
|
|
|
|
|
