tdTomato Red Fluorescent Protein | Antibodies & Live-Cell Imaging

tdTomato is a highly bright and photostable red fluorescent protein, widely used for live-cell imaging and multicolor labeling. As a member of the limited orange-red spectral probes derived from coral, it is particularly valuable for in vivo imaging and long-term reporter gene studies.

Overview

tdTomato is a highly bright and photostable red fluorescent protein, widely used for live-cell imaging and multicolor labeling. As a member of the limited orange-red spectral probes derived from coral, it is particularly valuable for in vivo imaging and long-term reporter gene studies.

Biorbyt provides high-quality tdTomato antibody to support detection and quantification in Western blot (WB) and immunofluorescence (IF) experiments.

What is tdTomato

tdTomato is a bright red fluorescent protein derived from coral, part of the limited group of orange-red spectral probes in the 560--650 nm range. It originates from dTomato, a dimeric variant of DsRed, which itself was generated from the intermediate dimer2 during the dissociation of tetrameric DsRed. tdTomato consists of two dTomato monomers connected by a 12-amino-acid linker, giving it two chromophores that confer exceptional brightness and photostability. N- and C-terminal extensions derived from GFP improve compatibility with fusion proteins and reduce mislocalization artifacts.

With an emission peak around 581 nm, tdTomato is ideal for live-cell imaging, multicolor experiments, and protein fusion studies using standard TRITC filter sets. Its high brightness, photostability, and low toxicity in cells and reporter gene mice make it suitable for long-term and in vivo imaging. Although its larger size may occasionally interfere with some fusion proteins, its advantages generally outweigh this limitation. Reliable tdTomato antibodies from Biorbyt further enable detection in Western blot (WB) and immunofluorescence (IF) assays.

Applications of tdTomato

1. Live-Cell Imaging and Multicolor Labeling

• Intrinsic fluorescence allows direct visualization in living cells.
• Suitable for multichannel confocal microscopy.
• Enables real-time tracking of protein localization and dynamics.

2. Protein Fusion Constructs

• tdTomato can be fused to target proteins for precise localization.
• Recombinant tdTomato protein can be used for experimental controls.
• Fusion proteins can be verified via Western blot (WB) or immunofluorescence (IF).

3. In Vivo Imaging / Reporter Gene Studies

• tdTomato is suitable for long-term imaging in cells and model organisms.
• Low toxicity enables use in reporter mice and live-animal imaging.

tdTomato Antibody

Biorbyt provides a series of high-quality tdTomato antibodies optimized for detecting tdTomato protein in a variety of assays. These antibodies allow researchers to validate and quantify tdTomato expression reliably.

Product Name	SKU	Applications	Size / Format	Price
tdTomato Goat Polyclonal Antibody, Literature-Validated (including Nature)	orb182397	ELISA, FACS, IF, IHC-Fr, IHC-P, WB	100 μg	$280
tdTomato Mouse Monoclonal Antibody	orb1338818	WB	100 μg	$600
tdTomato Goat Polyclonal Antibody	orb3127246	IF, IHC-Fr, WB	50 μl	$170

Red Fluorescent Protein Family

The Red Fluorescent Protein (RFP) family originates from DsRed, a tetrameric protein from Discosoma sp. coral. Understanding the family helps researchers select the optimal protein for fusion constructs, live-cell imaging, or multicolor experiments.

Protein	Structure	Emission Peak (nm)	Brightness	Stability	Notes
tdTomato	Tandem Dimer	554 / 581	95	Very High	The bright tandem dimer RFP detailed in the main text; ideal for tracking gene expression.
mCherry	Monomer	587 / 610	16	High	Popular monomeric RFP, strong photostability, widely used for fusion protein labeling and multicolor imaging.
mScarlet / mScarlet-I	Monomer	569 / 594	High	Good	Engineered high-performance monomeric RFP, fast maturation, suitable for live-cell and multicolor imaging.
mOrange	Monomer	548 / 562	49	Medium	Derived from mRFP1, bright orange-red RFP, good for protein tagging.
mPlum	Monomer	590 / 649	4.1	High	Far-red monomeric RFP with reasonable photostability, used in multicolor experiments.
mKate2	Monomer	588 / 635	Medium	Very High	Next-generation far-red RFP; longer emission for multicolor imaging, good brightness and photostability.

Notes: This table emphasizes commonly searched and widely used RFPs suitable for live-cell and in vivo applications. Other derivatives like dTomato and mStrawberry are less commonly used but part of the evolutionary lineage.

FAQ -- tdTomato Red Fluorescent Protein

Q1: Why can antibodies for RFP, mCherry, and tdTomato cross-react with each other?  
A: tdTomato, mCherry, and other RFPs share high sequence homology and conserved epitopes due to their derivation from DsRed. Polyclonal antibodies, and in some cases monoclonals, may recognize overlapping regions across these proteins. Researchers should select antibodies with validated epitope specificity and consider controls to minimize cross-reactivity.

Q2: What are the advantages of using tdTomato over mCherry or mScarlet?  
A: tdTomato's tandem dimer structure gives it extremely high brightness and photostability, making it ideal for tracking gene expression in live cells and in vivo imaging. While mCherry and mScarlet are monomers suited for fusion constructs, tdTomato is preferred when maximal fluorescence and long-term observation are required, provided the larger protein size does not interfere with fusion protein function.

Q3: Which filters are recommended for tdTomato imaging?  
A: tdTomato emits at ~581 nm, which aligns with standard TRITC filter sets. For multicolor imaging, use filter sets that minimize overlap with GFP, BFP, or other fluorophores to ensure clean signal separation.

Q4: Can tdTomato be used for in vivo imaging in animal models?  
A: Yes, tdTomato exhibits low toxicity and high photostability, making it suitable for long-term in vivo imaging in reporter mice or other model organisms. Its brightness allows deep tissue visualization and multi-day experiments without significant photobleaching.

Q5: How should tdTomato fusion proteins be validated?  
A: Fusion proteins should be verified using Western blot (WB) for expression size and immunofluorescence (IF) for subcellular localization. Using tdTomato-specific antibodies from Biorbyt, validated in multiple assays, ensures reliable detection while minimizing cross-reactivity with other RFPs.

Q6: What are the limitations of tdTomato?  
A: The main limitation is its larger molecular size due to the tandem dimer, which may affect fusion protein folding or function. It is not recommended for experiments where minimal tag size is critical. For monomeric fusion applications, mCherry or mScarlet may be preferable.

References

• Shaner, N. C., Campbell, R. E., Steinbach, P. A., Giepmans, B. N., Palmer, A. E., & Tsien, R. Y. (2004). Improved monomeric red, orange and yellow fluorescent proteins derived from Discosoma sp. red fluorescent protein. Nature Biotechnology, 22(12), 1567--1572. https://doi.org/10.1038/nbt1037
• Shaner, N. C., Steinbach, P. A., & Tsien, R. Y. (2005). A guide to choosing fluorescent proteins. Nature Methods, 2(12), 905--909. https://doi.org/10.1038/nmeth819
• Campbell, R. E., Tour, O., Palmer, A. E., Steinbach, P. A., Baird, G. S., Zacharias, D. A., & Tsien, R. Y. (2002). A monomeric red fluorescent protein. Proceedings of the National Academy of Sciences, 99(12), 7877--7882. https://doi.org/10.1073/pnas.082243699
• Shaner, N. C., Lambert, G. G., Chammas, A., et al. (2013). A bright monomeric green fluorescent protein derived from Branchiostoma lanceolatum. Nature Methods, 10, 407--409. https://doi.org/10.1038/nmeth.2413