Imaging 'intact' myofibrils with a near-field scanning optical microscope.
Fluorescently labelled myofibrils were imaged in physiological salt solution by near-field scanning optical microscopy and shear-force microscopy. These myofibrils were imaged in vitro, naturally adhering to glass while retaining their ability to contract. The Z-line protein structure of the myofibrils was antibody labelled and easily identified in the near-field fluorescence images. The distinctive protein banding structure of the myofibril was also seen clearly in the shear-force images without any labelling requirement. With the microscope in the transmission mode, resolution of the fluorescence images was degraded significantly by excessive specimen thickness (> 1 micron), whereas the shear-force images were less affected by specimen thickness and more affected by poor adherence to the substrate. Although the exact mechanism generating contrast in the shear-force images is still unknown, shear-force imaging appears to be a promising new imaging modality.
Seibel
E J
EJ
Centre for Bioengineering, University of Washington, Seattle 98195, USA. seibel@bioeng.washington.edu
Pollack
G H
GH
D000818:Animals; D005453:Fluorescence; D005455:Fluorescent Antibody Technique; D007091:Image Processing, Computer-Assisted; D008853:Microscopy / Q000295:instrumentation / Q000379:methods*; D008854:Microscopy, Electron; D009210:Myofibrils / Q000648:ultrastructure*; D016658:Psoas Muscles / Q000648:ultrastructure; D011817:Rabbits