Table 2.

Reported interactions of gap junction proteins with tight junction components

TJ protein	Via its	Cx	Cx motif	Main approachesa	Cell typesb	References
ZO-1	PDZ-2	Cx30		cl ci at	Mouse brain and spinal cord	[95]
	PDZ-2	Cx31.9	The most C-terminal residues	cl ci	HEK 293 cells	[38]
		Cx32		cl ci	Cultured rat hepatocytes	[22]
	PDZ-1	Cx35	Last 15 a.a. of C-terminus	cl ci at	Goldfish hindbrain	[45]
	PDZ-1	Cx36	Four C-terminal residues (SAYV)	cl ci em at	Mouse brain, HeLa cells	[43]
	PDZ-1		A 14-residue C-terminal fragment	cl ci at	HeLa cells, βTC-3, mouse pancreas and adrenal gland cells	[44]
				cl ci	PC12 cells	[118]
		Cx40		cl ci	Porcine vascular endothelial cells	[24]
	PDZs	Cx43	C-terminal 5 residues	cl ci at	HEK 293 cells, rat cardiomyocytes	[55]
	PDZ-2		Extreme C-terminal	cl ci dh	COS-7, Rat-1, mink lung epithelial cells	[56]
	PDZ-2		C-terminal 5 residues	cl ci em	Rat adult ventricular myocytes	[119]
				cl ci	42GPA9 cells, rat testis lysates	[120]
	PDZ-2		C-terminal	ci at	C57B16 mouse cortical astrocytes	[121]
	PDZ-2		Last 19 C-terminal residues	nmr		[35]
	PDZ-2		C-terminal (residues at the -3 position)	cl ci dh	MDCK cells	[37]
	PDZ-2			cl ci at	Mouse brain and spinal cord	[95]
	PDZ-2		C-terminal (amino acids 374–382)	cl at	HeLa cells, rat cardiomyocytes	[52]
				cl ci	Porcine vascular endothelial cells	[24]
	PDZ-2			cl ci	NRK and HEK293 cells	[98]
				cl ci	Newborn rat ventricular myocytes	[53]
		Cx43, Cx45		cl ci at	ROS 17/2.8 cells	[48,122]
	PDZs	Cx45	Four C-terminal residues (SVWI)	cl ci dh	MDCK cells	[39]
	PDZs		12 most C-terminal residues	cl ci at	ROS 17/2.8 cells	[57,123]
	PDZ-2			cl ci em at	HeLa cells	[29]
	PDZ-2	Cx46, Cx50	Most C-terminal residues	cl ci	Mouse lens	[40]
	PDZ-2		Most C-terminal residues	cl ci em at	Mouse lens	[42]
	PDZ-2	Cx47		cl ci em at	Mouse brain, HeLa cells	[41]
ZO-2		Cx43	C-terminal end	at	NRK cells	[124]
	PDZ-2	Cx43	C-terminal end	cl ci at	NRK, HEK 293T cells, heart tissues	[125]
ZO-3	PDZs	Cx45	C-terminal 4 residues	cl ci dh	MDCK cells	[39]
Occludin		Cx26		at	Human intestinal cell line T84	[23]
		Cx40, Cx43		cl ci	Porcine vascular endothelial cells	[24]
		Cx32		cl ci	CHST8 cells	[21]
				cl ci	Cultured rat hepatocytes	[22]
Claudin-1		Cx32		cl ci	Cultured rat hepatocytes	[22]
Claudin-5		Cx40, Cx43		cl ci	Porcine vascular endothelial cells	[24]

^abt: biochemical techniques (cell-free assays, chimeras, truncated connexins, mimetic peptides, oligomerization assays, chemical cross-linking tests, etc); cl: colocalization; ci: co-immunoprecipitation; dh: double hybrid; em: electron microscopy immuno labelling: at: affinity techniques (pull-down, affinity binding assays, surface plasmon resonance); nmr: nuclear magnetic resonance.

^bIn roman characters, cells where Cxs were endogenously expressed; in italics, cells where Cxs were exogenously expressed, surexpressed or mutated.