Table 2. Summary of some of the most used organelle-targeted indicators.

GEI	Organelle targeted
	PM	Nucleus	ER/SR	GA	Mitochondria	Acidic compartments	Peroxisomes
ATP:ADP	Pellegatti et al., 2005	Imamura et al., 2009	Vishnu et al., 2014		Gajewski et al., 2003; Imamura et al., 2009; Nakano et al., 2011; Lefkimmiatis et al., 2013
Calcium	Marsault et al., 1997; Mao et al., 2008	Brini et al., 1993; Bengtson et al., 2010; Giacomello et al., 2010; Simonetti et al., 2013	Kendall et al., 1992; Palmer et al., 2004; Tang et al., 2011; Kipanyula et al., 2012; de la Fuente et al., 2013; Rodriguez-Garcia et al., 2014; Suzuki et al., 2014; Henderson et al., 2015; Rodríguez-Prados et al., 2015; Waldeck-Weiermair et al., 2015; Navas-Navarro et al., 2016	Pinton et al., 1998; Lissandron et al., 2010; Wong et al., 2013; Aulestia et al., 2015; Rodríguez-Prados et al., 2015	Rizzuto et al., 1992, 1994; Arnaudeau et al., 2001; Griesbeck et al., 2001; Nagai et al., 2001; Rapizzi et al., 2002; Filippin et al., 2003, 2005; Palmer et al., 2006; Giacomello et al., 2010; Park et al., 2010; Alam et al., 2012; Jean-Quartier et al., 2012; Loro et al., 2012; Akerboom et al., 2013	Mitchell et al., 2001; Shen et al., 2012; McCue et al., 2013; Albrecht et al., 2015; Ronco et al., 2015	Drago et al., 2008; Lasorsa et al., 2008
cAMP	DiPilato et al., 2004; Dyachok et al., 2006; Terrin et al., 2006	DiPilato et al., 2004			DiPilato et al., 2004; Terrin et al., 2006; Di Benedetto et al., 2013; Lefkimmiatis et al., 2013
DG	Sato et al., 2006		Sato et al., 2006	Sato et al., 2006	Sato et al., 2006
ERK activity		Harvey et al., 2008
Glucose		Fehr et al., 2004	Fehr et al., 2005
Hydrogen Peroxide (H2O2)		Malinouski et al., 2011	Merksamer et al., 2008		Belousov et al., 2006; Malinouski et al., 2011; Ermakova et al., 2014		Malinouski et al., 2011
Phosphoinositides (PI3P2, PI3P3)	Sato, 2014	Ananthanarayanan et al., 2005	Sato, 2014	Sato, 2014	Sato, 2014
InsP3		Sato et al., 2005; Kapoor et al., 2014
Lactate		Barros et al., 2013
Mg2+		Lindenburg et al., 2013b
NADH-NAD+		Zhao et al., 2011			Hung et al., 2011; Zhao et al., 2011; Bilan et al., 2014
pH	Mukhtarov et al., 2013			Llopis et al., 1998; Miesenböck et al., 1998; Wu et al., 2000	Kneen et al., 1998; Llopis et al., 1998; Abad et al., 2004; Porcelli et al., 2005; Azarias and Chatton, 2011; Poburko et al., 2011; Tantama et al., 2011	Miesenböck et al., 1998; Ohara-Imaizumi et al., 2002; Zhu et al., 2009; Li and Tsien, 2012	Jankowski et al., 2001; Lasorsa et al., 2008
PKA	Allen and Zhang, 2006; Depry et al., 2011	Allen and Zhang, 2006	Liu et al., 2011		Allen and Zhang, 2006; Lefkimmiatis et al., 2013
PKC	Gallegos et al., 2006	Gallegos et al., 2006		Gallegos et al., 2006	Gallegos et al., 2006
Redox state/ROS			van Lith et al., 2011		Hanson et al., 2004; Gutscher et al., 2008; Liu et al., 2012a; Albrecht et al., 2014		Yano et al., 2010
Voltage	Storace et al., 2016
Zn2+			Qin et al., 2011	Qin et al., 2011	Dittmer et al., 2009; Miranda et al., 2012	Vinkenborg et al., 2009

References are provided for original works or reviews. For most of these sensors, the cytosolic forms are available and are not included in this table. Sensors for glutamate (Marvin et al., 2013), pyruvate (San Martín et al., 2014), G protein activation (van Unen et al., 2016), cGMP (Russwurm et al., 2007), and phosphate (Gu et al., 2006) are currently available only in the form localized in the cytosol.