Professor of Biology, Don Mykles holds one of the 300 tropical land crabs he collected last summer from the northeast coast of Puerto Rico. Crabs'ability to shrink their muscle tissue before molting may help scientists learn more about human muscle-wasting disease.
Stacked on metal racks in a climate-controlled animal research lab on the Colorado State University campus are 35 plastic cages holding a total of 300 tropical land crabs that could help scientists begin to understand and possibly prevent the muscle wasting that occurs in muscular dystrophy, cancer, serious infection, and other conditions.
Before crabs can shed their shells, their large claw muscles must shrink sufficiently so that they can be pulled through the small joints of the exoskeleton. Though this process is necessary and natural, it is similar to the tissue atrophy that occurs in many muscular diseases in humans, explained Professor of Biology Don Mykles. After molting, the crab's next task is to restore the muscle by building protein.
"Understanding how the muscle atrophy stops and then reverses itself could have human application," Mykles said. The key to unlocking this process may be found in "calpains," a family of calcium-dependent enzymes that break down protein. Mykles says there are at least four calpains in crab muscle tissue. He and several students last spring cloned one type of calpain and hope to complete clones of the other three within a year or so. Cloning would enable the scientists to measure the amounts of each calpain type, giving them a better idea of the function of each.
April Becker, a sophomore in biological sciences, is helping Mykles with related research on the Australian yabby, a type of freshwater crayfish. Becker is studying various claw muscle fiber types in the yabby to determine the role that each plays in muscle atrophy. From the perspective of an undergraduate student, the experience is hard to beat.
"What I learn in the lab is above and beyond what I'm studying in the basic 100- and 200-level classes," said Becker, who is a Hughes Undergraduate Research Scholar. "It's a great way to be exposed to practical applications of biology while giving a little help to a researcher at the same time."