Recombinant cells which express a fluorescent holo-phycobiliprotein fusion
protein and methods of use are described. The cells comprises a bilin, a
recombinant bilin reductase, an apo-phycobiliprotein fusion protein
precursor of the fusion protein comprising a corresponding
apo-phycobiliprotein domain, and a recombinant phycobiliprotein
domain-bilin lyase, which components react to form the
holo-phycobiliprotein fusion protein. Also described are
holo-phycobiliprotein based transcription reporter cells and assays, which
cells conditionally express a heterologous-to-the-cell, fluorescent, first
holo-phycobiliprotein domain.
