Structure, Regulation and Function of Gap Junctions in Liver

Figures & data

Figure 1. Structure of gap junctions. Gap junctions are formed by the docking of two hemichannels or connexons from neighboring cells, which in turn are built up by six connexins. Connexins share a similar structure consisting of four transmembrane domains (TM), two extracellular loops (EL), one cytosolic loop (CL), one cytosolic carboxyterminal tail (COOH) and one cytosolic aminotail (NH₂).

Table 1. Expression of connexins in liver.

Connexin species	Cell type	References
Cx26	Hepatocytes	Kuraoka et al. (1993), Nicholson et al. (1987) and Zhang and Nicholson (1989)
	Stellate cells	Fischer et al. (2005)
	Sinusoidal endothelial cells	Fischer et al. (2005)
	Kupffer cells	Fischer et al. (2005)
Cx32	Hepatocytes	Fischer et al. (2005), Fowler et al. (2013), Kumar and Gilula (1986), Kuraoka et al. (1993), Nakashima et al. (2004), Nicholson et al. (1987), Paul (1986) and Temme et al. (1998)
	Biliary endothelial cells	Bode et al. (2002)
	Sinusoidal endothelial cells	Fischer et al. (2005)
Cx37	Hepatic artery endothelial cells	Chaytor et al. (2001), Hernández-Guerra et al. (2014) and Shiojiri et al. (2006)
	Portal vein endothelial cells	Chaytor et al. (2001), Hernández-Guerra et al. (2014) and Shiojiri et al. (2006)
Cx40	Hepatic artery endothelial cells	Chaytor et al. (2001), Hernández-Guerra et al. (2014) and Shiojiri et al. (2006)
	Portal vein eindothelial cells	Chaytor et al. (2001), Hernández-Guerra et al. (2014) and Shiojiri et al. (2006)
Cx43	Biliary epithelial cells	Balasubramaniyan et al. (2013), Bode et al. (2002), Cogliati et al. (2011), Nathanson et al. (1999), Oyamada et al. (1990), Wang et al. (2013) and Zhang et al. (2007)
	Kupffer cells	Eugenin et al. (2007), Fischer et al. (2005), Gonzalez et al. (2002) and Saez et al. (1997)
	Stellate cells	Fischer et al. (2005) and Hernández-Guerra et al. (2014)
	Sinusoidal enothelial cells	Fischer et al. (2005) and Hernández-Guerra et al. (2014)
	Hepatic artery endothelial cells	Chaytor et al. (2001), Hernández-Guerra et al. (2014) and Shiojiri et al. (2006)
	Portal vein endothelials cells	Chaytor et al. (2001), Hernández-Guerra et al. (2014) and Shiojiri et al. (2006)

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