Clathrin and Cx43 gap junction plaque endoexocytosis

Gap Junctions

“…Gap junctions are also removed from the cell surface by gross internalization of the entire plaque, leaving large double-membrane vesicles in the cytoplasm (Albertini and Anderson 1975;Larsen et al 1979;Jordan et al 2001). Studies with cultured cells suggest that internalization is a clathrin-mediated process (Piehl et al 2007;Nickel et al 2008). The relationship between the removal of connexins from the center of pre-existing junctional plaques and the clathrin-dependent endocytosis of whole junctional plaques remains unclear.…”

Protein Kinase Cδ-mediated Phosphorylation of Connexin43 Gap Junction Channels Causes Movement within Gap Junctions followed by Vesicle Internalization and Protein Degradation

“…The monomeric GTPase Rab4 is associated with early endosomes, regulates recycling vesicle formation, and provides for vesicle sorting, before it reaches lysosomes for degradation (37,38). Clathrin also has been shown to play a role in endocytosis of clathrin-coated Cx43 containing vesicles internalized from gap junctions (39).…”

Smad ubiquitination regulatory factor-2 controls gap junction intercellular communication by modulating endocytosis and degradation of connexin43

“…Gap junctions are highly dynamic plasma membrane domains, and Cx43 has a half-life of 1.5-5 hours in most tissue types (Fallon and Goodenough, 1981;Laird et al, 1991). Cx43 is continually removed from the center of the gap junction plaque by clathrin-mediated endocytosis (Falk et al, 2009;Nickel et al, 2008;Piehl et al, 2007). During endocytosis of gap junctions, both membranes of the junction are internalized into one of the contacting cells, forming a double-membrane vesicle called an annular gap junction or connexosome (Falk et al, 2009;Jordan et al, 2001;Larsen and Hai-Nan, 1978;Leithe et al, 2006a;Leithe et al, 2012;Nickel et al, 2008;Piehl et al, 2007).…”

“…Cx43 is continually removed from the center of the gap junction plaque by clathrin-mediated endocytosis (Falk et al, 2009;Nickel et al, 2008;Piehl et al, 2007). During endocytosis of gap junctions, both membranes of the junction are internalized into one of the contacting cells, forming a double-membrane vesicle called an annular gap junction or connexosome (Falk et al, 2009;Jordan et al, 2001;Larsen and Hai-Nan, 1978;Leithe et al, 2006a;Leithe et al, 2012;Nickel et al, 2008;Piehl et al, 2007). Following endocytosis, connexins are degraded in lysosomes (Falk et al, 2009;Jordan et al, 2001;Laing et al, 1997;Leithe and Rivedal, 2004b;Leithe et al, 2006a;Naus et al, 1993;Nickel et al, 2008;Piehl et al, 2007;VanSlyke et al, 2000;Vaughan and Lasater, 1992).…”