Visualization of head-head interactions in the inhibited state of smooth muscle myosin

Citation
T. Wendt et al., Visualization of head-head interactions in the inhibited state of smooth muscle myosin, J CELL BIOL, 147(7), 1999, pp. 1385-1389
Citations number
30
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Cell & Developmental Biology
Journal title
JOURNAL OF CELL BIOLOGY
ISSN journal
0021-9525 → ACNP
Volume
147
Issue
7
Year of publication
1999
Pages
1385 - 1389
Database
ISI
SICI code
0021-9525(199912)147:7<1385:VOHIIT>2.0.ZU;2-N
Abstract
The structural basis for the phosphorylation-dependent regulation of smooth muscle myosin ATPase activity was investigated by forming two-dimensional (2-D) crystalline arrays of expressed un phosphorylated and thiophosphoryla ted smooth muscle heavy meromyosin (HMM) on positively charged lipid monola yers. A comparison of averaged 2-D projections of both forms at 2.3-nm reso lution reveals distinct structural differences, In the active, thiophosphor ylated form, the two heads of HMM interact intermolecularly with adjacent m olecules. In the unphosphorylated or inhibited state, intramolecular intera ctions position the actin-binding interface of one head onto the converter domain of the second head, thus providing a mechanism whereby the activity of both heads could be inhibited.