Cyan fluorescent protein TagCFP
- Bright cyan fluorescence
- Monomeric protein with successful performance in fusions
- Fast maturation, high pH-stability and photostability
- Proven suitability to generate stably transfected cell lines
- Recommended for protein labeling
TagCFP is a cyan monomeric protein generated on the basis of the wild-type GFP-like protein from jellyfish Aequorea macrodactyla [Xia et al., 2002]. It possesses bright fluorescence with excitation/emission maxima at 458 and 480 nm, respectively. TagCFP is significantly brighter than commonly used ECFP.
TagCFP 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.
TagCFP normalized excitation (thin line) and emission (thick line) spectra.
Spectra viewer tool
Download TagCFP spectra (xls)
|* Brightness is a product of extinction coefficient and quantum yield, divided by 1000.|
|Molecular weight, kDa||26.7|
|Polypeptide length, aa||239|
|Excitation maximum, nm||458|
|Emission maximum, nm||480|
|Extinction coefficient, M-1cm-1||37 000|
|Brightness, % of EGFP||64|
|Maturation rate at 37°C||fast|
|Cell toxicity||not observed|
|Main advantages||bright cyan monomeric fluorescent protein|
Recommended filter sets and antibodies
TagCFP can be recognized using Anti-Tag(CGY)FP antibody (Cat.# AB121) or Anti-GFP antibody (Cat.# AB011) available from Evrogen.
TagCFP can be detected using fluorescence filter sets for ECFP and the similar. Recommended Omega Optical filter sets are XF114-2 and XF130-2.
Performance and use
TagCFP can be easily expressed and detected in a wide range of organisms. Mammalian cells transiently transfected with TagCFP expression vectors produce bright fluorescence in 10-12 hrs after transfection. No cytotoxic effects or visible protein aggregation are observed.
TagCFP performance in fusions has been demonstrated in human cytoplasmic β-actin, α-tubulin, and mitochondria models.
TagCFP use for protein labeling.
Confocal microscopy of transiently transfected mammalian cells expressing TagCFP-tagged fusions: (A) α-tubulin; (B) β-actin.
See also 3D vizualization of TagCFP-α-tubulin fusion
TagCFP suitability to generate stably transfected cells has been proven by Marinpharm company. Cell lines expressing TagCFP are commercially available.
TagCFP use for labeling of cells and cellular orgenelles.
(A) Confocal microscopy of transiently transfected mammalian cells expressing TagCFP; (B) Mitochondria-targeted TagCFP in stably transfected U-205 cell line. Image was kindly provided by Dr. Christian Petzelt (Marinpharm).
TagCFP can be used in multicolor labeling applications with blue, green, yellow, red, and far-red fluorescent dyes.
Available variants and fusions
|Variant||Description||Related vector||Cat.#||Click for image|
TagCFP 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.
Human β-actin is fused to the TagCFP C-terminus. When expressed in mammalian cells, this fusion provides cyan fluorescent labeling of β-actin in living cells.
A mitochondrial targeting sequence (MTS) is fused to the TagCFP 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 cyan fluorescent labeling of mitochondria.
Haas J, Park EC, Seed B.
Codon usage limitation in the expression of HIV-1 envelope glycoprotein.
Curr Biol. 1996; 6 (3):315-24. / pmid: 8805248
Rizzuto R, Brini M, Pizzo P, Murgia M, Pozzan T.
Chimeric green fluorescent protein as a tool for visualizing subcellular organelles in living cells.
Curr Biol. 1995; 5 (6):635-42. / pmid: 7552174
Rizzuto R, Nakase H, Darras B, Francke U, Fabrizi GM, Mengel T, Walsh F, Kadenbach B, DiMauro S, Schon EA.
A gene specifying subunit VIII of human cytochrome c oxidase is localized to chromosome 11 and is expressed in both muscle and non-muscle tissues.
J Biol Chem. 1989; 264 (18):10595-600. / pmid: 2543673
Xia NS, Luo WX, Zhang J, Xie XY, Yang HJ, Li SW, Chen M, Ng MH.
Bioluminescence of Aequorea macrodactyla, a common jellyfish species in the East China Sea.
Mar Biotechnol (NY). 2002; 4 (2):155-62. / pmid: 14961275