Table 2. FRET sensor expression in adult mouse cardiomyocytes.

FRET probe	Citation	Full name	Detects	Donor	Acceptor	Linker	FRET time window (h)	Basal YFP intensity (a.u.)	Basal CFP intensity (a.u.)	Maximum YFP intensity (a.u.)	Maximum CFP intensity (a.u.)
AKAR3	Allen and Zhang, 2006	A kinase activity reporter 3	PKA activity	eCFP	Tandem cp173Venus pair	Binding domain from kemptide and substrate domain from 14-3-3, with a 14-aa sequence in between	35–50	980–1,010	313–330	1,049–1,080	255–265
cGi500	Russwurm et al., 2007	cGMP indicator-500 nM	[cGMP]	eCFP	eYFP	Cyclic nucleotide monophosphate binding domains A and B from PKG (Gln79-Tyr345)	35–50	3,803–3,901	1,049–1,101	3,471–3,207	1,143–1,208
Camui	Takao et al., 2005	Camui	CaMKII activity	CFP-S175G	Venus	Rat CaMKIIα	35–50	5,366–5,410	1,561–1,610	5,140–5,190	1,655–1,701
ICUE3	DiPilato and Zhang, 2009	Indicator of cAMP using Epac	[cAMP]	eCFP	Tandem cp194Venus pair	Epac1	n/a	2,108–2,210	660–810	2,120–2,209	659–808
Epac-SH187	Klarenbeek et al., 2015	Epac-based sensor #H187	[cAMP]	mTurquoise2	Tandem cp173Venus pair	Catalytically dead Epac1 with deletion of the membrane targeting sequence and a point mutation of Q270E	30–40	1,624–1,709	246–260	1,186–1,198	353–369