Work

Requirement of the two‐headed structure for the phosphorylation dependent regulation of smooth muscle myosin

Year: 1995

Type: article

Abstract: It is known for smooth muscle myosin that while acto-HMM ATPase activity is regulated by phosphorylation, acto-S-1 ATPase activity is not regulated. To clarify the heavy chain structure required for the regulation, smooth muscle myosin containing 7 different lengths of the S-2 portion were expressed in Sf9 insect cells using Baculovirus expression system. Myosin containing longer than 991 residues of heavy chain formed a stable two-headed structure while myosin with shorter than 944 residues of heavy chain formed a single-headed structure, indicating that the residues Gln945-Asp991 are critical for the formation of the two-headed structure. The actin activated ATPase activity of myosin mutants having a two-headed structure was activated by phosphorylation while that of myosin mutants that failed to form the two-headed structure was completely independent of phosphorylation. These results suggest that the two-headed structure is critical for the phosphorylation-dependent regulation.

Source: FEBS Letters

DOI: 10.1016/0014-5793(95)00326-5

Authors: Motoi Matsu-ura, Mitsuo Ikebe

Institutions: Case Western Reserve University, Meiji (Japan)

Language: English

Topic: Cardiomyopathy and Myosin Studies

Subfield: Cardiology and Cardiovascular Medicine

Field: Medicine

Domain: Health Sciences

Open Access status: bronze

Funders: National Institutes of Health, National Heart, Lung, and Blood Institute, National Institute of Arthritis and Musculoskeletal and Skin Diseases