The present invention provides novel, water-soluble, red-emitting
fluorescent rhodamine dyes and red-emitting fluorescent energy-transfer
dye pairs, as well as labeled conjugates comprising the same and methods
for their use. The dyes, energy-transfer dye pairs and labeled conjugates
are useful in a variety of aqueous-based applications, particularly in
assays involving staining of cells, protein binding, and/or analysis of
nucleic acids, such as hybridization assays and nucleic acid sequencing.