Fluorescent Proteins: Empty Backbones

The following tables list many popular fluorescent proteins and empty backbones for expression and cloning of fusion proteins, along with key parameters to help you plan your experiment. Tables are organized by color of the fluorescent protein.

The content for this page was originally compiled with the help of Erik Snapp.

Note for all tables:

• Brightness is the product of exctinction coefficient and quantum yield divided by 1,000. Note that the effective brightness of a fluorescent protein may vary depending on experimental conditions.
• pKa is the pH at which fluorescence intensity drops to half its maximum value.
• Maturation is the time for fluorescence to reach half its maximal value.
• Structure describes the oligomeric state of the protein. Many FPs are monomers at low concentration but are prone to dimerization at high concentration. Proteins that are derived from GFP and contain the A206K mutation are monomeric at all concentrations, so this is mutation is noted when present.

Looking for more empty backbones? Visit our Empty Backbones page or search our complete collection and filter by vector type, popularity, and more.

Blue/UV

Protein	Excitation (nm)	Emission (nm)	Brightness	pKa	Maturation	Structure	Plasmids
Sirius	355	424	4	3.0		Prone to dimerization	Sirius-N1 - Mammalian Expression
SBFP2	380	446	16	5.5		Monomer (A206K)	pSBFP2-C1 - Mammalian Expression
Azurite	383	450	14	5		Prone to dimerization	pLV-Azurite - Mammalian Lentiviral expression pB18cmBFPAzurite - Bacterial Expression
mAzurite	383	450	14	5		Monomer (A206K)	mAzurite-N1 - Mammalian Expression mAzurite-C1 - Mammalian Expression
EBFP2	383	448	18	5.3	25 min	Prone to dimerization	pBad-EBFP2 - Bacterial Expression EBFP2-N1 - Mammalian Expression EBFP2-C1 - Mammalian Expression EBFP2-pBAD - Bacterial Expression
moxBFP	385	448	17			Monomer (A206K)	moxBFP - Mammalian Expression
mKalama1	385	456	16	5.5		Monomer (A206K)	pBad-mKalama1 - Bacterial Expression
mTagBFP2	399	456	32	2.7	12 min	Prone to dimerization	mTagBFP2-pBAD - Bacterial Expression

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Cyan

Protein	Excitation (nm)	Emission (nm)	Brightness	pKa	Maturation	Structure	Plasmids
Aquamarine	420	474	23	3.3		Prone to dimerization	pPROEX Aqua - Bacterial Expression pAquaN1 - Mammalian Expression
ECFP	433	475	13	4.7		Prone to dimerization	pcDNA3-CFP - Mammalian Expression pCAG-CFP - Mammalian Expression
mCerulean	433	475	27	4.7		Monomer (A206K)	Cerulean - Mammalian Expression pCS2+8CCerulean - Zebrafish/Xenopus/Worm/Sea urchin pCS2+8NCerulean - Zebrafish/Xenopus/Worm/Sea urchin mCerulean N1 - Mammalian Expression mCerulean C1 - Mammalian Expression
mCerulean3	433	475	32	3.2		Monomer (A206K)	mCerulean3-N1 - Mammalian Expression mCerulean3-C1 - Mammalian Expression
moxCerulean3	434	474	36	3.2		Monomer (A206K)	moxCerulean3 - Mammalian Expression
SCFP3A	433	474	17	4.5		Monomer (A206K)	pSCFP3A-C1 - Mammalian Expression
mTurquoise2	434	474	28	3.1	33.5 min	Monomer (A206K)	pmTurquoise2-C1 - Mammalian Expression pmTurquoise2-N1 - Mammalian Expression
CyPet	435	477	18	5		Monomer	pCEP4CyPet-MAMM - Mammalian Expression pCyPet-C1 - Mammalian Expression pCyPet-His - Bacterial Expression CYPet-N1 - Mammalian Expression CYPet-C1 - Mammalian Expression
AmCyan1	453	486	11			Tetramer	AmCyan1-N1 - Mammalian Expression
mTFP1	462	492	54	4.3		Monomer	mTFP1-N1 - Mammalian Expression mTFP1-C1 - Mammalian Expression pNH082 - Worm Expression mTFP1-pBAD - Bacterial Expression
MiCy (Midoriishi-Cyan)	472	495	25	6.6		Dimer	MiCy-N1 - Mammalian Expression MiCy-C1 - Mammalian Expression MiCy-pBAD - Bacterial Expression

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Green

Protein	Excitation (nm)	Emission (nm)	Brightness	pKa	Maturation	Structure	Plasmids
AcGFP1	475	505	28			Prone to dimerization	AcGFP1-N1 - Mammalian Expression AcGFP1-C1 - Mammalian Expression
sfGFP (superfolder GFP)	485	507	54		14 min	Prone to dimerization	sfGFP-N1 - Mammalian Expression sfGFP-C1 - Mammalian Expression sfGFP-pBAD - Bacterial Expression
moxGFP	486	510	50		17 min	Monomer (A206K)	moxGFP - Mammalian Expression
mEmerald	487	509	39	6	11 min	Monomer (A206K)	mEmerald-N1 - Mammalian Expression mEmerald-C1 - Mammalian Expression mEmerald-pBAD - Bacterial Expression
EGFP	488	507	34	6	25 min	Prone to dimerization	pcDNA3-EGFP - Mammalian Expression pCAG-GFP - Mammalian Expression pLV-eGFP - Mammalian Lentiviral Expression Ac5-STABLE1-neo - Insect Expression pCS2+8CeGFP - Zebrafish/Xenopus/Worm/Sea urchin pCS2+8NeGFP - Zebrafish/Xenopus/Worm/Sea urchin pKT0128 - Yeast Expression EGFP-pBAD - Bacterial Expression
mEGFP	488	507	34	6		Monomer (A206K)	pmEGFP-1 - Mammalian Expression mEGFP-N1 - Mammalian Expression mEGFP-C1 - Mammalian Expression mEGFP-pBAD - Bacterial Expression
mAzamiGreen	492	505	41	5.8		Monomer	mAzami Green-N1 (mAG) - Mammalian Expression mAzami Green-C1 (mAG) - Mammalian Expression
cfSGFP2	493	517	34	5.4		Monomer (A206K)	cfSGFP2-N - Mammalian Expression (cysteine-free SGFP2)
ZsGreen	493	505	39			Tetramer	pHIV-Zsgreen - Mammalian Expression (this is a bicistronic vector rather than a fusion protein vector) ZsGreen1-N1 - Mammalian Expression
mWasabi	493	509	56	6.5		Monomer	mWasabi-N1 - Mammalian Expression mWasabi-C1 - Mammalian Expression
SGFP2	495	512	32	5.9		Monomer (A206K)	pSGFP2-C1 - Mammalian Expression
mStayGold (StayGold-E138D)	497	504	126	4.6	14 min	Monomer	pcDNA3-10His-mStayGold (E138D) - Mammalian Expression pET-MCN-10His-mStayGold (E138D) - Bacterial Expression pJRA110 - Plant Expression
mStayGold	499	510	136	4.8		Monomer	pRSETB/mStayGold - Bacterial Expression
mBaoJin (mStayGold)	500	508	119	4.4	7.6 min	Monomer	pBADHisB-Sumo-mBaoJin - Bacterial Expression P415 ymBaojin - Yeast Expression
mGreenLantern	503	514	73	5.6	14 min	Monomer (A206K)	pcDNA3.1-mGreenLantern - Mammalian Expression pAAV-CAG-mGreenLantern - Mammalian AAV Expression pBAD-mGreenLantern - Yeast Expression
Clover	505	515	84	6.1	30 min	Prone to dimerization	pcDNA3-Clover - Mammalian Expression pFA6a-link-yoClover-Kan - Yeast Expression
dClover2	505	515				Dimer (A206K)	dClover2-N1 - Mammalian Expression dClover2-C1 - Mammalian Expression
mClover3	506	518	85	6.5	44 min	Monomer (A206K)	pNCS-mClover3 - Bacterial Expression
mNeonGreen	506	517	93	5.7	10 min	Monomer	pCS2+mNeonGreen-C Cloning Vector - Mammalian Expression

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Yellow

Protein	Excitation (nm)	Emission (nm)	Brightness	pKa	Maturation	Structure	Plasmids
EYFP	513	527	51	6.9		Prone to dimerization	pcDNA3-YFP - Mammalian Expression
Topaz	514	527	57			Prone to dimerization	Topaz-N1 - Mammalian Expression Topaz-C1 - Mammalian Expression Topaz-pBAD - Bacterial Expression
mTopaz	514	527				Monomer (A206K)	mTopaz-N1 - Mammalian Expression mTopaz-C1 - Mammalian Expression mTopaz-pBAD - Bacterial Expression
moxVenus	514	526	44			Monomer (A206K)	moxVenus - Mammalian Expression
mVenus	515	528	53	6		Monomer (A206K)	mVenus N1 - Mammalian Expression mVenus C1 - Mammalian Expression pKT0090 - Yeast Expression mVenus-pBAD - Bacterial Expression
SYFP2	515	527	69	6		Monomer (A206K)	pSYFP2-C1 - Mammalian Expression
Hyperfolder YFP (hfYFP)	514	529	72	5.6	21 min	Prone to dimerization	pcDNA3.1-hfYFP - Mammalian Expression pBAD-hfYFP - Bacterial Expression
mhYFP	515	529	77	5.7	27 min	Monomer	pcDNA3.1-mhYFP - Mammalian Expression pBAD-mhYFP - Bacterial Expression
mGold	515	530	68	5.9		Monomer	pJL-mGold - Yeast Expression pCaggs-mGold - Mammalian Expression
mGold2s	517	529	90	5.1	15 min	Monomer (A206K)	pNCS-mGold2s - Bacterial Expression pJL-mGold2s - Yeast Expression pCaggs-mGold2s - Mammalian Expression
mGold2t	515	527	88	5.4	13 min	Monomer (A206K)	pNCS-mGold2t - Bacterial Expression pJL-mGold2t - Yeast Expression pCaggs-mGold2t - Mammalian Expression
mCitrine	516	529	59	5.7		Monomer (A206K)	mCitrine-N1 - Mammalian Expression mCitrine-C1 - Mammalian Expression pCS2+8CmCitrine - Zebrafish/Xenopus/Worm/Sea urchin pCS2+8NmCitrine - Zebrafish/Xenopus/Worm/Sea urchin pET mCitrine LIC cloning vector (u-mCitrine) - Bacterial Expression mCitrine-pBAD - Bacterial Expression
YPet	517	530	80	5.6		Prone to dimerization	pCEP4YPet-MAMM - Mammalian Expression pYPet-His - Bacterial Expression YPet-N1 - Mammalian Expression YPet-C1 - Mammalian Expression YPet-pBAD - Bacterial Expression
ZsYellow1	529	539	8			Tetramer	ZsYellow1-N1 - Mammalian Expression
mPapaya1	530	541	36	6.8		Monomer	mPapaya1-N1 - Mammalian Expression mPapaya1-C1 - Mammalian Expression
mCyRFP1	528	594	18	5.6		Monomer	pNCS-mCyRFP1 - Bacterial Expression mCyRFP1-C1 - Mammalian Expression

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Orange

Protein	Excitation (nm)	Emission (nm)	Brightness	pKa	Maturation	Structure	Plasmids
mKusabira-Orange (mKO)	548	559	31	5	4.5 h	Monomer	pQC mKorange IX - Mammalian Expression mKusabira Orange-C1 (mKO) - Mammalian Expression mKO-pBAD - Bacterial Expression
mOrange	548	562	49	6.5	2.5 h	Monomer	pET mOrange LIC cloning vector (u-mOrange) - Bacterial Expression pCS2+8CmOrange - Zebrafish/Xenopus/Worm/Sea urchin pCS2+8NmOrange - Zebrafish/Xenopus/Worm/Sea urchin mOrange-N1 - Mammalian Expression mOrange-C1 - Mammalian Expression mOrange-pBAD - Bacterial Expression
mOrange2	549	565	35	6.5	4.5 h	Monomer	mOrange2-N1 - Mammalian Expression mOrange2-C1 - Mammalian Expression mOrange2-pBAD - Bacterial Expression
mKO2	551	565	40	5.5		Monomer	mKO2-N1 - Mammalian Expression mKO2-C1 - Mammalian Expression mKO2-pBAD - Bacterial Expression
TurboRFP	553	574	62	4.4	1.5 h	Dimer	TurboRFP-pBAD - Bacterial Expression
tdTomato	554	581	95	4.7	1 h	Tandem-dimer	pCSCMV:tdTomato - Mammalian Expression pFA6a-link-tdTomato-SpHis5 - Yeast Expression tdTomato-N1 - Mammalian Expression tdTomato-C1 - Mammalian Expression tdTomato-pBAD - Bacterial Expression

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Red

Protein	Excitation (nm)	Emission (nm)	Brightness	pKa	Maturation	Structure	Plasmids
mScarlet-H	551	592	15	4.8	4.4 h	Monomer	pmScarlet-H_C1 - Mammalian Expression
mNectarine	558	578	26	6.9	30 min	Monomer	pBAD-mNectarine - Bacterial Expression
DsRed	558	583	49		> 24 h	Tetramer	mDsRed-C1 - Mammalian Expression mDsRed-N1 - Mammalian Expression
mRuby3	558	592	58	4.8	2.3 h	Monomer	pNCS-mRuby3 - Bacterial Expression mRuby3-C1 - Mammalian Expression
mRuby2	559	600	43	5.3	2.5 h	Monomer	pcDNA3-mRuby2 - Mammalian Expression pFA6a-link-yomRuby2-SpHis5 - Yeast Expression mRuby2-N1 - Mammalian Expression mRuby2-C1 - Mammalian Expression
eqFP611	559	611	35			Tetramer	eqFP611-N1 - Mammalian Expression
DsRed2	563	582	24			Tetramer	pCAG-DsRed2 - Mammalian Expression DsRed2-N1 - Mammalian Expression DsRed2-C1 - Mammalian Expression DsRed2-pBAD - Bacterial Expression
mApple	568	592	37	6.5	30 min	Monomer	mApple-N1 - Mammalian Expression mApple-C1 - Mammalian Expression mApple-pBAD - Bacterial Expression
mScarlet-I3	568	592	68	4.2	2 min	Monomer	pmScarlet-I3_C1 - Mammalian Expression pWXC078 - Worm Expression
mScarlet3	569	592	78	4.5	37 min	Monomer	pmScarlet3_C1 - Mammalian Expression pWXC077 - Worm Expression
mScarlet	569	594	71	5.3	2.9 h	Monomer	pmScarlet_C1 - Mammalian Expression pCS2+mScarlet-C Cloning Vector - Mammalian Expression
mScarlet-I	569	593	57	5.4	36 min	Monomer	pmScarlet-i_C1 - Mammalian Expression
mStrawberry	574	596	26	4.5	50 min	Monomer	mStrawberry-N1 - Mammalian Expression
FusionRed	580	608	18			Monomer	FusionRed-pBAD - Bacterial Expression
mRFP1	584	607	13	4.5	1 h	Monomer	pcDNA3-mRFP - Mammalian Expression pMXs-mRFP1 - Mammalian Retroviral Expression
mCherry	587	610	16	4.5	15 min	Monomer	pcDNA3 mCherry LIC cloning vector (6B) - Mammalian Expression pLV-mCherry - Mammalian Lentiviral Expression pCS2+8CmCherry - Zebrafish/Xenopus/Worm/Sea urchin pCS2+8NmCherry - Zebrafish/Xenopus/Worm/Sea urchin pET mCherry LIC cloning vector (u-mCherry) - Bacterial Expression pFA6a-link-yomCherry-SpHis5 - Yeast Expression
mCherry2	587	610				Monomer	mCherry2-N1 - Mammalian Expression mCherry2-C1 - Mammalian Expression

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Far-Red

Protein	Excitation (nm)	Emission (nm)	Brightness	pKa	Maturation	Structure	Plasmids
mCrimson3	588	615				Monomer	mCrimson3-N1 - Mammalian Expression mCrimson3-C1 - Mammalian Expression
HcRed1	588	618	0.3			Dimer	pCAG-HcRed - Mammalian Expression HcRed1-N1 - Mammalian Expression HcRed1-C1 - Mammalian Expression
dKatushka	588	635	22	5.5		Dimer	dKatushka-pBAD - Bacterial Expression
mKate1.31 (aka mKate2)	588	635	25			Monomer	mKate1.31-pBAD - Bacterial Expression
mPlum	590	649	4	4.5	100 min	Monomer	pQC mPlum IX - Mammalian Expression mPlum-N1 - Mammalian Expression mPlum-C1 - Mammalian Expression mPlum-pBAD - Bacterial Expression
mRaspberry	598	625	13		55 min	Monomer	mRaspberry-N1 - Mammalian Expression
TagRFP675	598	675	4	5		Prone to dimerization	pTagRFP675-N1 - Mammalian Expression pBAD/HisD-TagRFP675 - Bacterial Expression
mNeptune	600	650	13	5.4	35 min	Prone to dimerization	pcDNA3-mNeptune2-N - Mammalian Expression
mNeptune2	600	650	21			Prone to dimerization	mNeptune2-N1 - Mammalian Expression mNeptune2-C1 - Mammalian Expression
mCarmine	603	675	5.81	5.58		Monomer	mCarmine in pcDNA3 - Mammalian Expression mCarmine in pRSETB - Bacterial Expression
mCardinal	604	659	17	5.3	27 min	Prone to dimerization	mCardinal-N1 - Mammalian Expression mCardinal-C1 - Mammalian Expression mCardinal-pBAD - Bacterial Expression
mMaroon1	609	657	8.8	6.2	20 min	Monomer	mMaroon-N1 - Mammalian Expression mMaroon-C1 - Mammalian Expression
E2-Crimson	611	646	29	4.5	24 min	Tetramer	pAAV-CAG-E2-Crimson - Mammalian AAV Expression pEB2-E2-Crimson - Bacterial Expression
TagRFP657	611	657	0.34	5.3	27 min	Prone to dimerization	pTagRFP657-N1 - Mammalian Expression pTagRFP657-C1 - Mammalian Expression pFA6a-link-yoTagRFP657-Kan - Yeast Expression
smURFP	642	670	32	3.2	39 min	Prone to dimerization	pLenti-smURFP - Mammalian Expression

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Near-Infrared

Protein	Excitation (nm)	Emission (nm)	Brightness	pKa	Maturation	Structure	Plasmids
emiRFP670	642	670	12	4.5		Monomer	pemiRFP670-N1 - Mammalian Expression
miRFP670	642	670	12	4.5	3 h	Monomer	pmiRFP670-N1 - Mammalian Expression pLenti6.2_miRFP670 - Mammalian Lentiviral Expression pBAD/His-miRFP670 - Bacterial Expression
iRFP670	643	670	13	4	~5 h	Dimer	piRFP670-N1 - Mammalian Expression pBAD/HisB-iRFP670 - Bacterial Expression
miRFP670nano3	645	670	24	4.2		Monomer	pcDNA-miRFP670nano3 - Mammalian Expression pAAV-hSYN-miRFP670nano3-WPRE-hGHpA - Mammalian AAV Expression pBAD/His-miRFP670nano3 - Bacterial Expression
miRFP680	661	680	14	4.5		Monomer	pmiRFP680-N1 - Mammalian Expression pAAV-CAG-miRFP680 - Mammalian AAV Expression pDRF1 ymiRFP680 - Yeast Expression
iRFP682	663	682	10	4.5	~5 h	Dimer	piRFP682-N1 - Mammalian Expression pBAD/HisB-iRFP682 - Bacterial Expression
miRFP703	673	703	8	4.5		Monomer	pmiRFP703-N1 - Mammalian Expression pBAD/His-miRFP703 - Bacterial Expression
iRFP702	673	702	7.4	4.5	~5 h	Dimer	piRFP702-N1 - Mammalian Expression pBAD/HisB-iRFP702 - Bacterial Expression
emiRFP703	674	703	8	4.5		Monomer	pemiRFP703-N1 - Mammalian Expression
miRFP709	683	709	4	4.5		Monomer	pmiRFP709-N1 - Mammalian Expression pBAD/His-miRFP709 - Bacterial Expression
mIFP	683	704	7	3.5		Monomer	mIFP-N1 - Mammalian Expression mIFP24-C1 - Mammalian Expression
IFP2.0	684	708	7			Prone to dimerization	IFP2.0-N1 - Mammalian Expression IFP2.0-C1 - Mammalian Expression
iRFP (aka iRFP713)	690	713	6	4.5	2.8 h	Dimer	piRFP - Mammalian Expression pBAD/His-B-iRFP - Bacterial Expression
miRFP713	690	713	7	3.5		Monomer	pAAV-CAG-miRFP713 - Mammalian AAV Expression pmiRFP713-N1 - Bacterial Expression
iRFP720	702	720	6	4.5	~5 h	Dimer	piRFP720-N1 - Mammalian Expression pBAD/HisB-iRFP720 - Bacterial Expression
miRFP720	702	720	6	4.5		Monomer	pmiRFP720-N1 - Mammalian Expression pAAV-CAG-miRFP720 - Mammalian AAV Expression

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Long Stokes Shift

These proteins have a large gap between their excitation and emission maxima (Stokes shift), useful for applications like multicolor imaging with better spectral separation.

Protein	Excitation (nm)	Emission (nm)	Brightness	pKa	Maturation	Structure	Plasmids
Free Use GFP (fuGFP)	395	503				Monomer	pUS252 - Mammalian Expression
T-Sapphire	399	511	26	4.9	1.3 h	Prone to dimerization	pFA6a-link-yETSapphire-CaUra3 - Yeast Expression
mT-Sapphire	399	511	26	4.9	2.6 h	Monomer (A206K)	mT-Sapphire-N1 - Mammalian Expression mT-Sapphire-C1 - Mammalian Expression mT-Sapphire-pBAD - Bacterial Expression
LSSmGFP	400	510	18	4.7		Monomer (A206K)	pcDNA3.1-LSSmGFP - Mammalian Expression pBAD-LSSmGFP - Bacterial Expression
mAmetrine	406	526	26	6	1.8 min	Monomer (A206K)	pBad-mAmetrine - Bacterial Expression mAmetrine-N1 - Mammalian Expression mAmetrine-C1 - Mammalian Expression
LSSmOrange	437	572	23	5.7	2.3 h	Monomer	pLSSmOrange-C1 - Mammalian Expression pLSSmOrange-N1 - Mammalian Expression pBAD-LSSmOrange - Bacterial Expression
mKeima (pH sensitive)	440	620	3.5	6.5	3 h	Monomer	pFA6a-link-yomKeima-CaURA3 - Yeast Expression mKeima-Red-N1 - Mammalian Expression mKeima-Red-C1 - Mammalian Expression
dKeima	440	616	7.6	6.5		Dimer	dKeima-Red-N1 - Mammalian Expression
LSSmCherry1	450	610	10	6.2		Monomer	pBAD-LSSmCherry1 - Bacterial Expression
LSS-mKate1	463	624	2.5	3.2	100 min	Monomer	pLSSmKate1-N1 - Mammalian Expression pLSSmKate1-C1 - Mammalian Expression pBAD/HisD-LSSmKate1 - Bacterial Expression
LSSmKate2	460	605	4.4	2.7	2.5 h	Monomer	pLSSmKate2-N1 - Mammalian Expression pBAD/HisD-LSSmKate2 - Bacterial Expression LSSmKate2-C1 - Mammalian Expression

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Photoactivatable (Off to On)

Excitation and Emission wavelengths after activation.

Protein	Excitation (nm)	Emission (nm)	Activation (nm)	Brightness	pKa	Maturation	Structure	Plasmids
PA-sfGFP	485	511	400				Prone to dimerization	PA-sfGFP-N1 - Mammalian Expression PA-sfGFP-C1 - Mammalian Expression
mPA-Emerald	487	509	400				Monomer (A206K)	mPA-Emerald-N1 - Mammalian Expression mPA-Emerald-C1 - Mammalian Expression
PA-GFP	504	517	400	14			Monomer (A206K)	pPAGFP-N1 - Mammalian Expression pPAGFP-C1 - Mammalian Expression pRSETA-PAGFP - Bacterial Expression pFA6a-PA-GFP-kanMX6 - Yeast Expression pFA6a-link-yEPAGFP-CaUra3 - Yeast Expression
PATagRFP	562	595	405	25	5.3	75 min	Prone to dimerization	pBAD/HisD-PATagRFP - Bacterial Expression
PAmCherry1	564	595	405	8	6.3	23 min	Monomer	pPAmCherry1-N1 - Mammalian Expression pPAmCherry1-C1 - Mammalian Expression pBAD/HisB-PAmCherry1 - Bacterial Expression
PAmCherry2	570	596	405	13	6.2	18 min	Monomer	pPAmCherry2-C1 - Mammalian Expression
PAmCherry3	570	596	405	5	6.2	25 min	Monomer	pPAmCherry3-C1 - Mammalian Expression
PAmKate	568	628	405	5	5.6	19 min	Monomer	pPAmKate-N1 - Mammalian Expression pBAD/HisB-PAmKate - Bacterial Expression
PAiRFP1	690	717	660 or 750	3			Dimer	pPAiRFP1-N1 - Mammalian Expression pBAD/HisB-PAiRFP1 - Bacterial Expression
PAiRFP2	692	719	660 or 750	3			Dimer	pPAiRFP2-N1 - Mammalian Expression pBAD/HisB-PAiRFP2 - Bacterial Expression

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Photoconvertible (e.g. Green to Red)

Protein	Excitation (nm)	Emission (nm)	Transition (nm)	Brightness	pKa	Maturation	Structure	Plasmids
Dendra2	490 553	507 573	405	23 19	6.6 6.9		Monomer	pcDNA3.1 Dendra2 - Mammalian Expression pEG545 - Worm Expression
mMaple3	491 568	506 583	405	5.8 12			Monomer	pmMaple3-CAM - Bacterial Expression
mEos2	506 571	516 581	405	47 30	5.6 6.4		Prone to dimerization	pRSETa mEos2 - Bacterial Expression pFA6a-link-yomEos2-CaURA3 - Yeast Expression
mEos3.2	507 572	516 580	405	53 18	5.4 5.8	20 min	Monomer	mEos3.2-N1 - Mammalian Expression mEos3.2-C1 - Mammalian Expression
mEos4a	505 569	516 581	405 or 480	72 43	5.3 5.7		Monomer	mEos4a-N1 - Mammalian Expression mEos4a-C1 - Mammalian Expression
mEos4b	505 569	516 581	405	66 39	5.5 5.8		Monomer	mEos4b-N1 - Mammalian Expression mEos4b-C1 - Mammalian Expression
tdEos	505 569	516 581	405	55 20			Tandem dimer	tdEos-N1 - Mammalian Expression tdEos-C1 - Mammalian Expression
mKikGR	507 583	517 593	390	18 34	5.2 6.6		Monomer	mKikGR-N1 - Mammalian Expression mKikGR-C1 - Mammalian Expression
Kaede	508 572	518 580	380	87 20	5.6 5.6		Tetramer	Kaede-N1 - Mammalian Expression Kaede-C2 - Mammalian Expression
PSmOrange	548 634	565 662	480	58 9	6.2 5.6	1.6 h	Monomer	pPSmOrange-N1 - Mammalian Expression pPSmOrange-C1 - Mammalian Expression pFA6a-link-yoPSmOrange-SpHis5 - Yeast Expression
PSmOrange2	546 619	561 651	489	31 7	6.6 5.4	3.5 h	Monomer	pPSmOrange2-N1 - Mammalian Expression pBAD-PSmOrange2 - Bacterial Expression

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Reversibly Photoswitchable (e.g. Off to On to Off)

Protein	Excitation (nm)	Emission (nm)	Activation (nm)	Brightness	pKa	Maturation	Structure	Plasmids
rsTagRFP	567	585	440 (Off to On) 567 (On to Off)	4.0	6.6	43 min	Prone to dimerization	prsTagRFP-N1 - Mammalian Expression prsTagRFP-C1 - Mammalian Expression pBAD/HisD-rsTagRFP - Bacterial Expression
iLOV	447	497	467 (On to Off) Spontaneous (Off to On)				Monomer	pEiLOV-N1 - Mammalian Expression pGEX iLOV - Bacterial Expression iLOV-N1 - Mammalian Expression iLOV-C1 - Mammalian Expression
rsEGFP2	478	503	408 (Off to On) 503 (On to Off)	18	5.8	20 min		pcDuex2-rsEGFP2-E - Mammalian Expression pQE31-rsEGFP2 - Bacterial Expression
rsEGFP1	493	510	405 (Off to On) 491 (On to Off)	17	6.5	3 h		rsGFP1-pBAD - Bacterial Expression
Dronpa3	490	515	405 (Off to On) 490 (On to Off)	19			Monomer	Dronpa3-N1 - Mammalian Expression Dronpa3-C1 - Mammalian Expression
Dronpa	503	518	400 (Off to On) 503 (On to Off)	81		40 min	Monomer	pcDuex2-Dronpa - Mammalian Expression
Skylan-NS	499	511	405 (Off to On) 488 (On to Off)	79	5.7		Monomer	pSkylan-NS-N1 - Mammalian Expression
mGeos-M	503	514	405 (Off to On) 488 (On to Off)	44	4.7		Monomer	mGeos-M-N1 - Mammalian Expression mGeos-M-C1 - Mammalian Expression

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Fluorescent Timers

Fluorescent protein variants that change their fluorescence from the blue to red over time, allowing tracking of processes such as intracellular trafficking or cell cycle dynamics.

Protein	Excitation (nm)	Emission (nm)	Brightness	pKa	Maturation	Structure	Plasmids
Fast-FT	403 583	466 606	14.9 6.8	2.8 4.1	7.1 h (red)	Monomer	pFast-FT-N1 - Mammalian Expression pTRE-Fast-FT - Mammalian Expression pSCMV-H2B-FT-Fast - Mammalian Expression pBAD/HisB-Fast-FT - Bacterial Expression
Medium-FT	401 579	464 600	18.4 5.8	2.7 4.7	3.9 h (red)	Monomer	pMedium-FT-N1 - Mammalian Expression pTRE-Medium-FT - Mammalian Expression pSCMV-H2B-FT-Medium - Mammalian Expression pBAD/HisB-Medium-FT - Bacterial Expression
Slow-FT	402 583	465 604	11.7 4.2	2.6 4.6	28 h (red)	Monomer	pSlow-FT-N1 - Mammalian Expression pTRE-Slow-FT - Mammalian Expression pSCMV-H2B-FT-Slow - Mammalian Expression pBAD/HisB-Slow-FT - Bacterial Expression

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Self-Labeling Tags

These tags have been engineered to covalently bind a synthetic substrate conjugated to an organic fluorophore or other small molecule. By using different ligand-dye conjugates, you can label one fusion protein with different colors as needed for your experiments. Learn more about the flexibility of self-labeling tags on our blog.

Protein	Ligand	Plasmids
HaloTag	Chloralkane (CA)	pMH-Halo tag - Mammalian Gateway Destination Vector pENTR4-HaloTag (w876-1) - Gateway Entry Vector pCS2+/C-Halo, pCS2+/N-Halo - Xenopus Expression pET51b-His-TEV-HaloTag7 - Bacterial Expression
SNAP-Tag	Benzylguanine (BG)	pSNAP-tag (m) Vector - Mammalian Expression pSNAPf-C1 - Mammalian Expression pENTR4-SNAPf (w878-1) - Gateway Entry Vector pCS2+/C-SNAPf, pCS2+/N-SNAPf - Xenopus Expression pSNAP-tag (T7) Vector - Bacterial Expression
CLIP-Tag	Benzylcytosine (BC)	pCLIP-tag (m) Vector - Mammalian Expression pENTR4-CLIPf (w877-2) - Gateway Entry Vector pET51b-His-TEV-CLIP-tag - Bacterial Expression

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Additional Resources

Plasmid Kits and Collections

• Empty Backbone Collection
• Michael Davidson Fluorescent Protein Collection
• Botman-Teusink Yeast Fluorescent Protein Collection
• Hamdoun Lab Fluorescent Protein Fusion Construct Kit
• Neveu Lab MXS Chaining Kit
• Luciferase Plasmid Collection
• Promega Plasmid Collection

Reading and Resources

• Addgene Blog: Which Fluorescent Protein Should I Use?
• Addgene Blog: Choosing Your Fluorescent Proteins for Multi-Color Imaging
• FPbase: an open-source, community-editable database for fluorescent proteins created by Talley Lambert

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Content last reviewed: 25 September 2025