PROCEEDINGS ARTICLE | February 23, 2012
Proc. SPIE. 8225, Imaging, Manipulation, and Analysis of Biomolecules, Cells, and Tissues X
KEYWORDS: Proteins, Second-harmonic generation, Femtosecond phenomena, Tissues, Imaging systems, Microscopy, Luminescence, Wave propagation, Harmonic generation, Assembly equipment
Utilizing a custom-built, on-stage incubator-combined, two-photon excitation fluorescence (TPEF) and second
harmonic generation (SHG) imaging system, we observed new-sarcomere addition in rat neonatal cardiomyocytes
during 10 hours of on-stage incubation. This addition occurred at one end of an existing myofibril, the sides of
existing myofibrils, and at the interstice of several separated myofibrils; in the cases of the latter two, we observed
mature myofibrils acting as templates. We found that during sarcomeric addition, myosin filaments are assembled
onto the premyofibril laterally. This lateral addition, which proceeds stepwise along the axial direction, plays an
important role in the accumulation of Z-bodies to form mature Z-disks and in the regulation of sarcomeric length
during maturation.
