Yellow fluorescent protein TagYFP

- Bright yellow fluorescence
- Monomeric protein with successful performance in fusions
- High pH stability and photostability
- Recommended for protein labeling

TagYFP is a monomeric yellow fluorescent protein developed on the basis of GFP-like protein from jellyfish Aequorea macrodactyla [Xia et al., 2002]. TagYFP possesses single excitation maximum at 508 nm, and emission maximum at 524 nm. TagYFP is more pH stable than EYFP. TagYFP is mainly intended for protein labeling in protein localization and interaction studies. It can also be used for cell and organelle labeling and for tracking the promoter activity, although TurboYFP and Phi-Yellow proteins are preferable for such applications because they mature faster and give brighter fluorescent signal.

Main properties

TagYFP normalized excitation (thin line) and emission (thick line) spectra. Download TagYFP spectra (xls)

CHARACTERISTIC *Brightness is a product of extinction coefficient and quantum yield, divided by 1000. Molecular weight, kDa 27.0 Polypeptide length, aa 239 Fluorescence color yellow Excitation maximum, nm 508 Emission maximum, nm 524 Quantum yield 0.62 Extinction coefficient, M-1cm-1 50 000 Brightness* 31 Brightness, % of EGFP 94 pKa 5.5 Structure monomer Aggregation no Maturation rate at 37°C fast Photostability high Cell toxicity not observed Main advantages bright yellow monomeric fluorescent protein

Recommended filter sets and antibodies

The protein can be recognized using Anti-Tag(CGY)FP antibody (Cat.# AB121-AB122) available from Evrogen.

Recommended Omega Optical filter sets for TagYFP are XF104-3 and XF105-2. It can also be detected using Chroma Technology Corp. filter set 41028 Yellow GFP BP (10C/Topaz) or the similar.

Performance and use

TagYFP can be easily expressed and detected in a wide range of organisms. Mammalian cells transiently transfected with TagYFP expression vectors give bright fluorescent signals within 10-12 hrs after transfection. No cell toxic effects and visible protein aggregation are observed.

		TagYFP use for labeling of cells and cellular orgenelles. Confocal microscopy of transiently transfected mammalian cells expressing TagYFP.

TagYFP performance in fusions has been demonstrated in human cytoplasmic β-actin and α-tubulin models. An expected pattern of fluorescence has been obtained in each case.

		TagYFP use for protein labeling. Confocal microscopy of transiently transfected mammalian cells expressing TagYFP fusions.

TagYFP suitability to generate stably transfected cells has been proven by Marinpharm company. Cell lines expressing TagYFP fusions are commercially available.

		Stably transfected cell lines expressing TagYFP fusions. (A) MDCK cells expressing TagYFP-tubulin fusion; (B) U-205 cells expressing TagYFP-actin fusion. Images were kindly provided by Dr. Christian Petzelt (Marinpharm).

TagYFP can be used in multicolor labeling applications with cyan, green, red, and far-red fluorescent dyes.

		Multicolor labeling using TagFPs. (A) TagCFP-tagged β-actin (cyan), TagYFP-tagged α-tubulin (yellow), TagFP635-H2B fusion (red), and Golgi-targeted TagRFP (violet); (B) TagCFP-tagged α-tubulin (cyan), TagFP635-clathrin fusion (red), mitochondria-targeted TagYFP (yellow). Images were kindly provided by Michael W. Davidson (Florida State University).

Available variants and fusions

TagYFP codon usage is optimized for high expression in mammalian cells [Haas et al., 1996], but it can be successfully expressed in many other heterological systems.

TagYFP-mito fusion: A mitochondrial targeting sequence (MTS) is linked to the TagYFP N-terminus. MTS was derived from the subunit VIII of human cytochrome C oxidase [Rizzuto et al., 1989; Rizzuto et al., 1995]. When expressed in mammalian cells, this variant provides yellow fluorescent labeling of mitochondria.

TagYFP-actin fusion: Human β-actin is linked to the TagYFP C-terminus. When expressed in mammalian cells, this fusion provides yellow fluorescent labeling of actin filaments.

TagYFP-tubulin fusion: Human α-tubulin is linked to the TagYFP C-terminus. When expressed in mammalian cells, this fusion provides yellow fluorescent labeling of tubulin filaments.