Andy Chervenak, Graduate Student, Cell and Developmental Biology
The green structure in this picture is the siphon of a marine squid. The siphon sucks water into the squid and then rapidly expels it to propel the squid through the ocean. Surrounding muscles can change the direction of the jet of water, so that the squid can control its direction. Thus, the squid is a wonderful model for the study of muscle development and function, but it is more well known for another specialization, its giant axon, or nerve fiber, that is 1,000 times wider than the axons present in humans. For nearly a century, scientists have studied the squid giant axon to understand how nerves conduct electricity and how nerve cells communicate with muscle and with other nerve cells. Disturbances in these nerve communication functions are responsible for the symptoms in Alzheimer's Disease and other adult-onset neurodegenerative diseases, such as Parkinson's and ALS.