Engineering Of Living Cells For The Expression Of Holo-phycobiliprotein-based Constructs

University of California System: University of California, Berkeley
posted on 05/28/2009

• request more info 
•   
•  LICENSE ONLINE

Purified native phycobiliproteins and their subunits fluoresce strongly and, since 1982, have been widely used as labels for cell sorting and analysis, and in a wide range of other fluorescence based assays. This invention embodies the use of phycobiliproteins and phycobiliprotein fusions as in vivo fluorescent protein probes.

Fluorescent protein probes expressed in vivo, such as Aequorea victoria green fluorescent protein (GFP) and its variants are of great value in many fields of research in cell biology, such as studies of protein localization in cells, cell division, organelle dynamics and vesicle trafficking, developmental biology, reporting gene expression, assessing uptake and expression of DNA in transfection experiments, etc.
Phycobiliproteins can be used in all of the applications that currently use GFPs. Moreover, phycobiliproteins are superior fluorophores to GFPs. They absorb and emit at higher wavelengths than GFPs, and have comparable quantum yields but much higher extinction coefficients [see, A. J. Tooley, Y. A. Cai, and A. N. Glazer (2001) Proc. Natl. Acad. Sci. USA, Vol. 98, 10560-10565].

Furthermore, these probes can be used in conjunction with GFPs or phytofluors [J.T. Murphy and J.C. Lagarias (1997) Curr. Biol. 7, 870-876; G. A. Gambetta and J. C.Lagarias (2001) Proc. Natl. Acad. Sci. USA, Vol. 98, 10566-10571] where it is desired to use multiple intracellular fluorescent labels, or in applications that require fluorescence energy transfer (FRET).