Table 2.
Evidence in literature for cardiac expression of K2P channel subunits at mRNA or protein level in different species.
| K2P Channel Subunit | Species | Protein /mRNA | Observation | Citation |
|---|---|---|---|---|
|
K2P1.1
(TWIK-1) |
Zebrafish | mRNA (RT-PCR, ISH) | Ubiquitous kcnk1a and kcnk1b ortholog mRNA in embryonic heart | [11] |
| Mouse | mRNA (RT-PCR) | No cardiac mRNA abundance | [17] | |
| Mouse | mRNA (RT-qPCR, TaqMan) | Moderate cardiac mRNA abundance, V > A | [16] | |
| Rat | mRNA (RT-PCR) | Moderate cardiac mRNA abundance, A > V | [18] | |
| Rat | mRNA (RT-PCR) | Moderate cardiac mRNA abundance | [15] | |
| Rat | mRNA (RT-qPCR, TaqMan) | Cardiac mRNA abundance mRNA detected in sinoatrial tissue |
[19] | |
| Human | mRNA (NB) | Cardiac mRNA abundance | [20] | |
| Human | mRNA (RT-PCR) | Cardiac mRNA abundance, V > A | [21] | |
| Human | mRNA (RT-qPCR, TaqMan) | Cardiac mRNA abundance, A > V Highest mRNA level among all K2P channels |
[10] | |
| Human | mRNA (RT-qPCR) | Cardiac mRNA abundance, A>V | [13] | |
| Human | mRNA (RT-qPCR) | mRNA detected in human ventricular tissue mRNA detected in iPS-derived cardiomyocytes |
[22] | |
| Human | mRNA (RT-qPCR, TaqMan) | Cardiac mRNA abundance | [23] | |
| Human | mRNA (Affymetrix chip and RT-qPCR, TaqMan) | Cardiac mRNA abundance, A > Purkinje fibers > V | [12] | |
| Human | mRNA (Affymetrix chip, RT-qPCR, TaqMan) and protein (WB) | Cardiac mRNA abundance, A > Purkinje fibers > V Cardiac protein expression, A > V |
[14] | |
|
K2P2.1
(TREK-2) |
Mouse | mRNA (NB) | Cardiac mRNA abundance | [24] |
| Mouse | mRNA (RT-PCR) | Cardiac mRNA abundance, V > A | [17] | |
| Mouse | mRNA (RT-PCR) | Cardiac mRNA abundance | [25] | |
| Mouse | mRNA (RT-qPCR) and protein (WB) | Cardiac mRNA abundance, V > A Cardiac protein expression |
[26] | |
| Mouse | mRNA (RT-qPCR, TaqMan) | Cardiac mRNA levels, V > A | [16] | |
| Mouse | Protein (IF) | Protein expression in isolated ventricular cardiomyocytes | [27] | |
| Rat | mRNA (RT-PCR) | mRNA abundance in isolated ventricular cardiomyocytes | [28] | |
| Rat | mRNA (RT-PCR) | Cardiac mRNA abundance, A and V | [18] | |
| Rat | mRNA (RT-PCR) | Cardiac mRNA abundance, A and V | [29] | |
| Rat | mRNA (RT-PCR) | Endocardial mRNA levels > epicardial mRNA expression | [30] | |
| Rat | mRNA (RT-PCR) | Cardiac mRNA levels, mRNA detected in cardiomyocytes |
[15] | |
| Rat | mRNA (RT-PCR) | Cardiac mRNA abundance | [31] | |
| Rat | mRNA (RT-qPCR) | Cardiac mRNA abundance Cardiac mRNA adult heart > fetal heart |
[18] | |
| Rat | mRNA (RT-qPCR, TaqMan) | Cardiac mRNA abundance in sinoatrial tissue | [19] | |
| Rat | mRNA (RT-PCR)and protein (IF) | Cardiac mRNA abundance, A and V Protein expression in isolated cardiomyocytes |
[32] | |
| Rat | mRNA (RT-PCR) and protein (IF) | mRNA and protein expression in rat cardiomyocytes | [33] | |
| Rat | mRNA (RT-PCR) and protein (WB, IF) | Cardiac mRNA and protein expression, A and V | [34] | |
| Rabbit, mouse | Protein (WB) | Cardiac protein expression, SAN > A > V | [35] | |
| Pig | mRNA (RT-qPCR, TaqMan) and protein (WB) | Cardiac mRNA and protein expression, V = A mRNA and protein expression in sinoatrial and atrioventricular node |
[36] | |
| Pig, human | mRNA (RT-qPCR, TaqMan) | Atrial mRNA expression in human and pig | [37] | |
| Human | mRNA (RT-PCR) | Cardiac mRNA abundance | [31] | |
| Human | mRNA (RT-qPCR) | Low cardiac mRNA abundance | [38] | |
| Human | mRNA (RT-qPCR) | Low cardiac mRNA abundance | [39] | |
| Human | mRNA (RT-qPCR) | Cardiac mRNA abundance, V Low mRNA abundance in iPS-derived cardiomyocytes |
[22] | |
| Human | mRNA (RT-qPCR) | Cardiac mRNA abundance | [39] | |
| Human | mRNA (RT-qPCR, TaqMan) | Cardiac mRNA abundance, V > A | [10] | |
| Human | mRNA (RT-qPCR, TaqMan) | Low cardiac mRNA abundance | [23] | |
| Human | mRNA (RT-qPCR, TaqMan) | Cardiac mRNA levels, V > A | [40] | |
| Human, mouse | mRNA (RT-qPCR, TaqMan) and protein (WB) | Cardiac mRNA and protein expression in human and mice, V > A | [41] | |
| Human | Protein (WB) | Cardiac protein expression | [42] | |
| Human | Protein (WB) | Cardiac protein expression | [43] | |
|
K2P3.1
(TASK-1) |
Chicken embryo | mRNA (ISH) and protein (IF) | Cardiac mRNA and protein expression in chicken embryos | [44] |
| Mouse, human | mRNA (NB) | Human and Mouse: Cardiac mRNA abundance | [45] | |
| Mouse | mRNA (RT-PCR) | Cardiac mRNA abundance | [17] | |
| Mouse | mRNA (RT-qPCR) | Cardiac mRNA levels, V > A | [26] | |
| Mouse | mRNA (RT-PCR) and protein (WB) | Cardiac protein expression | [25] | |
| Mouse, human | mRNA (RT-qPCR, TaqMan) | Cardiac mRNA expression | [46] | |
| Mouse | mRNA (RT-qPCR, TaqMan) and protein (WB) | Cardiac mRNA and protein expression, A and V | [16] | |
| Rat | mRNA (RT-qPCR, TaqMan) | Cardiac mRNA abundance in sinoatrial tissue | [19] | |
| Rat | mRNA (NB, RT-PCR) | Cardiac mRNA abundance, A and V | [47] | |
| Rat | mRNA (RT-PCR) | Cardiac mRNA abundance, cardiomyocyte mRNA abundance | [15] | |
| Rat | mRNA (RT-PCR) | Cardiac mRNA abundance | [48] | |
| Rat | mRNA (RT-PCR) | Cardiac mRNA abundance, A > V | [18] | |
| Rat, guinea pig, human | mRNA (RT-qPCR, TaqMan) | Human: Cardiac mRNA levels, V > A Rat: Cardiac mRNA abundance, A and V Guinea pig: Cardiac mRNA levels, V > A |
[49] | |
| Dog | Protein (WB) | Atrial protein expression | [50] | |
| Pig | mRNA (RT-qPCR, TaqMan) and protein (WB) | Cardiac mRNA and protein expression mRNA abundance in sinoatrial and atrioventricular node |
[51] | |
| Pig | mRNA (RT-qPCR, TaqMan) and protein (WB) | Cardiac mRNA and protein expression | [52] | |
| Human | mRNA (RT-qPCR) | Low cardiac mRNA abundance | [38] | |
| Human | mRNA (RT-qPCR) | mRNA abundance in Purkinje fibers | [5] | |
| Human | mRNA (RT-qPCR) | Cardiac mRNA abundance, A > V Cardiac mRNA adult heart > fetal heart |
[39] | |
| Human | mRNA (RT-qPCR) | Low mRNA abundance in human ventricular tissue mRNA abundance in iPS-derived cardiomyocytes |
[22] | |
| Human | mRNA (RT-qPCR, TaqMan) | mRNA levels in isolated atrial cardiomyocytes > in isolated atrial fibroblasts | [53] | |
| Human | mRNA (RT-qPCR, TaqMan) | Cardiac mRNA abundance | [23] | |
| Human | mRNA (RT-qPCR, TaqMan) | Cardiac mRNA levels, A > V | [54] | |
| Human | mRNA (Affymetrix chip and RT-qPCR, TaqMan) | Cardiac mRNA abundance, A | [55] | |
| Human | mRNA (Affymetrix chip and RT-qPCR, TaqMan) | Cardiac mRNA levels, A > V Expression in Purkinje fibers |
[14] | |
| Human | mRNA (Affymetrix chip and RT-qPCR, TaqMan) | Cardiac mRNA expression, A > V | [12] | |
| Human | mRNA (RT-qPCR) and protein (IF) | Cardiac mRNA and protein expression | [56] | |
| Human | mRNA (RT-qPCR, TaqMan) and protein (WB) | Cardiac mRNA levels, A > V Cardiac protein expression, A |
[40] | |
| Human | mRNA (RT-qPCR, TaqMan) and protein (WB) | Cardiac mRNA levels, A > V Cardiac protein expression, A |
[10] | |
| Human | mRNA (bulk RNAseq) | Cardiac mRNA levels, A > V | [57] | |
|
K2P4.1
(TRAAK) |
Mouse | mRNA (RT-PCR, NB) | No cardiac mRNA detectable | [58] |
| Mouse | mRNA (RT-qPCR) | Human: no cardiac mRNA detectable Mouse: Low cardiac mRNA abundance, A > V |
[41] | |
| Mouse | mRNA (qRT-PCR) and protein (WB) | Cardiac mRNA abundance | [26] | |
| Mouse | mRNA (RT-qPCR, TaqMan) | No cardiac mRNA levels detectable | [16] | |
| Rat | mRNA (RT-PCR) | No cardiac mRNA levels | [15] | |
| Rat | mRNA (RT-PCR) | Low cardiac mRNA levels, A and V | [18] | |
| Human | mRNA (RT-qPCR) | mRNA abundance in human ventricular tissue mRNA abundance in iPS-derived cardiomyocytes |
[22] | |
| Human | mRNA (RT-qPCR) | Low cardiac mRNA levels | [59] | |
| Human | mRNA (RT-qPCR, TaqMan) | Very low cardiac mRNA levels | [10] | |
| Human | mRNA (RT-qPCR, TaqMan) | No cardiac mRNA abundance | [23] | |
|
K2P5.1
(TASK-2) |
Mouse | mRNA (RT-PCR) | Cardiac mRNA abundance | [17] |
| Mouse | mRNA (RT-PCR) | Cardiac mRNA levels, A and V | [26] | |
| Mouse | mRNA (RT-PCR) | Low cardiac mRNA abundance | [25] | |
| Mouse | mRNA (RT-qPCR, TaqMan) | Cardiac mRNA levels, A > V | [16] | |
| Rat | mRNA (NB) | No cardiac mRNA abundance | [60] | |
| Rat | mRNA (RT-PCR) | Low cardiac mRNA levels, A and V | [18] | |
| Rat | mRNA (RT-qPCR, TaqMan) | Cardiac mRNA abundance in sinoatrial tissue | [19] | |
| Human | mRNA (RT-PCR) | Cardiac mRNA abundance | [61] | |
| Human | mRNA (RT-qPCR, TaqMan) | Cardiac mRNA abundance | [23] | |
| Human | mRNA (RT-qPCR) | mRNA abundance in human ventricular tissue mRNA abundance in iPS-derived cardiomyocytes |
[22] | |
| Human | mRNA (RT-qPCR) | Cardiac mRNA abundance | [56] | |
| Human | mRNA (RT-qPCR, TaqMan) | Cardiac mRNA levels, A > V | [10] | |
| Human | mRNA (Affymetrix chip and RT-qPCR, TaqMan) | Cardiac mRNA levels, A > V mRNA abundance in Purkinje fibers |
[14] | |
| Human | mRNA (RT-qPCR) and protein (WB) | Very low cardiac mRNA levelsDetectable protein levels | [38] | |
|
K2P6.1
(TWIK-2) |
Mouse | mRNA (RT-qPCR, TaqMan) | Moderate cardiac mRNA abundance, A and V | [16] |
| Mouse | mRNA (RT-qPCR) and protein (WB) | Low cardiac mRNA abundance, A and V Cardiac protein expression |
[26] | |
| Rat | mRNA (RT-PCR) | Cardiac mRNA abundance Cardiac mRNA adult heart > fetal heart Highest mRNA abundance in right atrium |
[18] | |
| Rat | mRNA (RT-PCR) | Cardiac mRNA abundance | [62] | |
| Rat | mRNA (RT-PCR) | Moderate cardiac mRNA abundance | [15] | |
| Rat | mRNA (RT-qPCR, TaqMan) | Cardiac mRNA abundance in sinoatrial tissue | [19] | |
| Human | mRNA (NB) | No cardiac mRNA abundance | [17] | |
| Human | mRNA (Hybridization array) | Cardiac mRNA levels, V > A | [62] | |
| Human | mRNA (RT-qPCR) | mRNA abundance in human ventricular tissue mRNA abundance in iPS-derived cardiomyocytes |
[22] | |
| Human | mRNA (RT-qPCR, TaqMan) | Low cardiac mRNA abundance | [23] | |
| Human | mRNA (RT-qPCR, TaqMan) | Cardiac mRNA levels, V > A | [10] | |
|
K2P7.1
(TWIK-3) |
Mouse | mRNA (RT-qPCR, TaqMan) | No cardiac mRNA abundance detectable | [16] |
| Human | mRNA (RT-qPCR) | Cardiac mRNA abundance | [63] | |
| Human | mRNA (RT-qPCR, TaqMan) | Cardiac mRNA abundance | [23] | |
| Human | mRNA (RT-qPCR, TaqMan) | Very low cardiac mRNA levels, A > V | [10] | |
|
K2P9.1
(TASK-3) |
Mouse | mRNA (RT-qPCR, TaqMan) | No cardiac mRNA abundance detectable | [16] |
| Mouse | mRNA (RT-qPCR) | Low cardiac mRNA abundance | [26] | |
| Mouse | mRNA (RT-PCR) | Low cardiac mRNA abundance | [25] | |
| Rat | mRNA (RT-PCR) | Low cardiac mRNA abundance, A and V | [18] | |
| Rat | mRNA (RT-PCR) | Cardiac mRNA abundance | [48] | |
| Rat | mRNA (RT-PCR) | Cardiac mRNA abundance, cardiomyocyte mRNA expression | [15] | |
| Rat, guinea pig, human | mRNA (RT-qPCR, TaqMan) | Human: very low cardiac mRNA abundance Rat: no cardiac mRNA abundance Guinea pig: low cardiac mRNA abundance, V > A |
[49] | |
| Guinea pig | mRNA (RT-PCR) | No cardiac mRNA abundance | [64] | |
| Human | mRNA (RT-qPCR) | Moderate mRNA abundance in human ventricular tissue mRNA abundance in iPS-derived cardiomyocytes |
[22] | |
| Human | mRNA (RT-qPCR, TaqMan) | Very low cardiac mRNA levels, A > V | [10] | |
| Human | mRNA (RT-qPCR, TaqMan) | Cardiac mRNA abundance | [23] | |
| Human | mRNA (RT-qPCR) an protein (IF) | Strong cardiac mRNA and protein expression | [56] | |
|
K2P10.1
(TREK-2) |
Mouse | mRNA (RT-qPCR, TaqMan) | No cardiac mRNA abundance detectable | [16] |
| Rat | mRNA (RT-PCR) | Cardiac mRNA levels, A > V | [18] | |
| Rat | mRNA (RT-PCR) | Moderate cardiac abundance | [15] | |
| Rat | mRNA (RT-PCR, NB) | No cardiac mRNA abundance | [65] | |
| Human | mRNA (RT-qPCR) | mRNA abundance in human ventricular tissue mRNA abundance in iPS-derived cardiomyocytes |
[22] | |
| Human | mRNA (RT-qPCR, TaqMan) | Mild cardiac mRNA abundance, A > V | [41] | |
| Human | mRNA (RT-qPCR, TaqMan) | Low cardiac mRNA abundance | [23] | |
| Human | mRNA (RT-qPCR, TaqMan) | Low cardiac mRNA levels, A > V | [10] | |
|
K2P12.1
(THIK-2) |
Mouse | mRNA (RT-PCR) | Very low cardiac mRNA abundance | [15] |
| Mouse | mRNA (RT-qPCR, TaqMan) | No cardiac mRNA levels detectable | [16] | |
| Rat | mRNA (RT-PCR) | No cardiac mRNA abundance | [66] | |
| Human | mRNA (NB) | Cardiac mRNA abundance | [67] | |
| Human | mRNA (RT-qPCR, TaqMan) | Very low cardiac mRNA abundance, A and V | [10] | |
|
K2P13.1
(THIK-1) |
Zebrafish | mRNA (RT-PCR) | Cardiac mRNA abundance | [68] |
| Mouse | mRNA (RT-PCR) | Cardiac mRNA abundance | [15] | |
| Mouse | mRNA (RT-qPCR) | Cardiac mRNA abundance | [26] | |
| Mouse | mRNA (RT-qPCR, TaqMan) | Very low cardiac mRNA abundance | [16] | |
| Rat | mRNA (RT-PCR) | Cardiac mRNA abundance | [66] | |
| Human | mRNA (RT-qPCR) | mRNA abundance in human ventricular tissue mRNA abundance in iPS-derived cardiomyocytes |
[22] | |
| Human | mRNA (RT-qPCR, TaqMan) | Low cardiac mRNA abundance | [23] | |
| Human | mRNA (RT-qPCR, TaqMan) | Low cardiac mRNA abundance, A > V | [10] | |
|
K2P15.1
(TASK-5) |
Mouse | mRNA (RT-qPCR) | Cardiac mRNA abundance | [26] |
| Mouse | mRNA (RT-qPCR, TaqMan) | Very low cardiac mRNA abundance | [16] | |
| Rat | mRNA (RT-PCR) | No cardiac mRNA abundance | [48] | |
| Rat | mRNA (RT-PCR) | Moderate cardiac abundance | [15] | |
| Human | mRNA (RT-PCR) | Cardiac mRNA abundance | [69] | |
| Human | mRNA (RT-PCR, NB) | No cardiac mRNA abundance | [70] | |
| Human | mRNA (RT-qPCR, TaqMan) | Low cardiac mRNA abundance, A and V | [10] | |
|
K2P16.1
(TALK-1) |
Rat | mRNA (NB) | No cardiac mRNA abundance | [60] |
| Rat | mRNA (RT-PCR) | Moderate cardiac abundance | [15] | |
| Human | mRNA (NB) | No cardiac mRNA abundance | [67] | |
| Human | mRNA (RT-PCR, NB) | No cardiac mRNA abundance | [71] | |
| Human | mRNA (RT-qPCR, TaqMan) | Very low cardiac mRNA abundance, A and V | [10] | |
|
K2P17.1
(TALK-2) |
Zebrafish | mRNA (RT-PCR) | No cardiac abundance | [72] |
| Rat | mRNA (NB) | Cardiac mRNA abundance | [60] | |
| Human | mRNA (NB) | Cardiac mRNA abundance | [67] | |
| Human | mRNA (RT-PCR) | Cardiac mRNA levels, A > V | [73] | |
| Human | mRNA (RT-qPCR) | mRNA abundance in human ventricular tissue mRNA abundance in iPS-derived cardiomyocytes |
[22] | |
| Human | mRNA (RT-qPCR) | Cardiac mRNA abundance | [56] | |
| Human | mRNA (RT-qPCR) | Cardiac mRNA abundance mRNA abundance in sinoatrial and atrioventricular node Purkinje fibers > A > V |
[5] | |
| Human | mRNA (single cell RT-qPCR) and protein (IF) | mRNA and protein abundance in iPS-derived cardiomyocytes |
[74] | |
| Human | mRNA (RT-qPCR, TaqMan) | Cardiac mRNA levels, A > V | [10] | |
| Human | mRNA (RT-qPCR, TaqMan) and protein (WB) | Cardiac mRNA and protein expression | [40] | |
| Human | Protein (WB) | Cardiac protein expression, A | [75] | |
|
K2P18.1
(TRESK) |
Zebrafish | mRNA (ISH) | No cardiac abundance | [76] |
| Mouse | mRNA (RT-qPCR, TaqMan) | Very low cardiac mRNA abundance | [77] | |
| Mouse | mRNA (RT-qPCR, TaqMan) | Very low cardiac mRNA abundance | [16] | |
| Human | mRNA (RT-PCR) | No cardiac mRNA abundance | [61] | |
| Human | mRNA (RT-PCR) | No cardiac mRNA abundance | [78] | |
| Human | mRNA (RT-qPCR, TaqMan) | Very low cardiac mRNA abundance | [10] |
A, expression in atrial tissue; IF, immunofluorescence; iPS, induced pluripotent stem cell; ISH, in situ hybridization; LA, left atrium; NB, Northern blot; RT-PCR, reverse transcriptase PCR; RT-qPCR, reverse transcriptase quantitative PCR; RA, right atrium; TAC, transverse aortic constriction; TaqMan, reverse transcriptase quantitative PCR employing TaqMan® hydrolyse probes to increase specificity; V, expression in ventricular tissue; WB, Western blot.