Zebrafish study yields observation of muscle formation

Understanding how muscle cells form is crucial to developing new treatments for diseases such as muscular dystrophy and to treating muscle injuries. However, while scientists have focused on muscle cells in culture, they know little about how muscle cells form in a developing embryo.

In this month’s issue of the journal Developmental Cell, Clarissa Henry, assistant professor in the University of Maine Dept. of Biological Sciences, reports findings from a study of muscle cell development in zebrafish embryos. Looking at the formation of two types of muscle fibers, Henry and co-author Sharon L. Amacher of the University of California, Berkeley, describe a process regulated by a gene known as Hedgehog.

The article is titled “Zebrafish Slow Muscle Cell Migration Induces a Wave of Fast Muscle Morphogenesis.” It is based on research at the University of California, Berkeley where Henry was a post-doctoral scientist before coming to UMaine.

The authors show that cells leading to the formation of so-called “slow twitch” muscle fibers can induce the formation of “fast twitch” fibers. These two types of fibers differ in their structure and ability to exert force for extended periods of time.

The mechanism of communication between slow and fast twitch cells is unknown, but it is likely, the authors write, that similar examples will be found in other types of tissues.

The findings describe “how fast muscle fibers form in zebrafish, which is a fantastic model system for development in general and muscular dystrophy in particular,” says Henry.