Conventional boundary crossed

The myosins are a large and diverse group of proteins that interact with actin to generate motility at the tissue level and within the subcellular environment, but only a few members of this superfamily have been characterized. In the July 25 Journal of Biological Chemistry, Steven Rosenfeld and colleagues at the University of Alabama report the biochemical analysis of the kinetics and enzymology of the myosin IIB isoform. Myosin II is the predominant class found in muscles and is historically referred to as "conventional" myosin; the other 19 classes are currently referred to as the "unconventional" myosins. The IIB isoform constitutes most of the myosin found in the central nervous system and all of the nonmuscle myosin in the heart. Their analyses reveal that myosin IIB, although a conventional myosin, exhibits properties of unconventional myosins (Journal of Biological Chemistry, DOI:10.1074/jbc.M302555200, July 25, 2003).

Rosenfeld et al. synthesized myosin IIB protein ...