Probing myosin structural conformation in vivo by second-harmonic generation microscopy.

ABSTRACT: Understanding of complex biological processes requires knowledge of molecular structures and measurement of their dynamics in vivo. The collective chemomechanical action of myosin molecules (the molecular motors) in the muscle sarcomere represents a paradigmatic example in this respect. Here, we describe a label-free imaging method sensitive to protein conformation in vivo. We employed the order-based contrast enhancement by second-harmonic generation (SHG) for the functional imaging of muscle cells. We found that SHG polarization anisotropy (SPA) measurements report on the structural state of the actomyosin motors, with significant sensitivity to the conformation of myosin. In fact, each physiological/biochemical state we probed (relaxed, rigor, isometric contraction) produced a distinct

SUBMITTER: Nucciotti V 

PROVIDER: S-EPMC2867856 | biostudies-literature | 2010 Apr

REPOSITORIES: biostudies-literature