
113
Molecular Structure and Order with Second-Harmonic Generation Microscopy
characterized by a high HRS. e possible molecular origin of SHG in the muscle has been studied in
several types of preparations; the rst interesting indication came from the colocalization of the bright
SHG bands with the uorescence from GFP-myosin heavy chain in nematode muscles (Campagnola
etal., 2002). Using mouse myobrils, Plotnikov etal. (2006) showed that SHG signal does not colocal-
ize with either
α
-actinin (immunostained) or actin (labeled at the ends with rhodamine–phalloidin).
Another measurement relevant for the identication of SHG source consists