Propidium iodide and the thiol-specific reagent DACM as a dye pair for fluorescence resonance energy transfer analysis: an application to mouse sperm chromatin.

摘要: The dyes N-(-7-dimethylamino-4-methyl-coumarinyl) maleimide and propidium iodide, specific for the thiol group DNA, respectively, were considered as a donor-acceptor couple suitable investigating “in situ” relative spatial distribution of DNA protamines in mouse spermatozoa chromatin. two are characterized by favourable spectral properties, so that simplified analytical procedure, based on measurement both donor acceptor emission double-stained samples, can be applied to evaluate efficiency energy transfer process its topological distribution. results obtained indicate during maturation process: 1) basic arrangement protamine-DNA complex does not undergo structure changes, 2) oxidation sulfhydryl disulfide groups, resulting chromatin stabilization, first involves protamine thiols spatially closer DNA. Fluorescence imaging suggests stabilization starts midportion sperm head, then spreads towards periphery. © 1994 Wiley-Liss, Inc.