PUBLICATION HIGHLIGHT
Hidden in the muscle: The structure of myosin
It has long been known that actin and myosin, two major protein filaments, are involved in the contraction of muscles. Sarcomeric myosins can form regular bipolar thick filaments and, in conjunction with actin thin filaments, form the functional contractile unit of both skeletal and cardiac muscle. Consequently, at the center of the pumping ability of the heart and the movement of body is this incredibly important interaction between actin and myosin.
However, despite this vast physiological importance in the body, the structure of the myosin rod remained relatively unknown. This structure is especially relevant due to the fact that a great number of mutations in the myosin rod lead to skeletal and cardiac myopathies. This lack of understanding is mainly due to the complications introduced by the nature of the myosin rod. For example, crystallization of the rod became difficult since high salt conditions would be needed to form the higher-level structure. Additionally, skip residues introduce flexibility between the coiled segments of the protein, providing further complications.
As a result, the researchers, including SBGrid member Ivan Rayment, worked to elucidate this structure by dividing this myosin rod into smaller protein segments using globular proteins, specifically Gp6 and Xrcc4, to enhance the crystallization.
Consequently, these researchers used a computational approach to combine these sections of the myosin rod into one extended model of the protein. In doing so, they have laid the groundwork for an expanded understanding of the myosin rod which is integral in skeletal and cardiac muscle contraction.
Read about this discovery in Protein.
Kristen Rodrigues is a graduate of the Harvard-MIT Health Sciences & Technology PhD program in Medical Engineering and Medical Physics with a concentration in Biological Engineering.
Originally published at https://www.tumblr.com on December 7, 2015.
