Arrizubieta M J, Bandman E
Department of Food Science and Technology, University of California, Davis 95616, USA.
Biochem Biophys Res Commun. 1998 Mar 17;244(2):588-93. doi: 10.1006/bbrc.1998.8105.
Interhelical electrostatic interactions at specific heptad positions can regulate dimerization specificity of alpha-helical coiled-coils. We have analyzed 20 vertebrate myosin sequences from a variety of organisms and tissues in order to determine if interhelical ionic interactions correlate with the observed myosin dimerization specificity. We find that the sites for potential interhelical ion pairing are identical in virtually all sarcomeric myosins whether they form homo- or heterodimers. We also show that smooth muscle and non-muscle myosin rod sequences exhibit a different conserved pattern of potential interhelical ion pairing. These observations suggest that myosin rod residues involved in interhelical electrostatic interactions do not regulate dimerization specificity, but may contribute to the specific arrangements of myosin molecules that determine differences in the filament morphology of sarcomeric and non-sarcomeric muscles.
特定七肽位置的螺旋间静电相互作用可调节α-螺旋卷曲螺旋的二聚化特异性。我们分析了来自多种生物体和组织的20个脊椎动物肌球蛋白序列，以确定螺旋间离子相互作用是否与观察到的肌球蛋白二聚化特异性相关。我们发现，几乎所有肌节肌球蛋白中潜在的螺旋间离子配对位点都是相同的，无论它们形成同二聚体还是异二聚体。我们还表明，平滑肌和非肌肉肌球蛋白杆序列表现出不同的潜在螺旋间离子配对保守模式。这些观察结果表明，参与螺旋间静电相互作用的肌球蛋白杆残基并不调节二聚化特异性，但可能有助于肌球蛋白分子的特定排列，这些排列决定了肌节和非肌节肌肉细丝形态的差异。
