Connexin and pannexin mediated cell-cell communication

The Dominick P. Purpura Department of Neuroscience, Albert Einstein College of Medicine, NY, 10461, USA.
Neuron Glia Biology (Impact Factor: 6.64). 08/2007; 3(3):199-208. DOI: 10.1017/S1740925X08000069
Source: PubMed

ABSTRACT In this review, we briefly summarize what is known about the properties of the three families of gap junction proteins, connexins, innexins and pannexins, emphasizing their importance as intercellular channels that provide ionic and metabolic coupling and as non-junctional channels that can function as a paracrine signaling pathway. We discuss that two distinct groups of proteins form gap junctions in deuterostomes (connexins) and protostomes (innexins), and that channels formed of the deuterostome homologues of innexins (pannexins) differ from connexin channels in terms of important structural features and activation properties. These differences indicate that the two families of gap junction proteins serve distinct, complementary functions in deuterostomes. In several tissues, including the CNS, both connexins and pannexins are involved in intercellular communication, but have different roles. Connexins mainly contribute by forming the intercellular gap junction channels, which provide for junctional coupling and define the communication compartments in the CNS. We also provide new data supporting the concept that pannexins form the non-junctional channels that play paracrine roles by releasing ATP and, thus, modulating the range of the intercellular Ca(2+)-wave transmission between astrocytes in culture.

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Available from: Eliana Scemes, Jul 30, 2015
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    • "stem cells which implement regeneration are not locally controlled ( since the cells were direct neighbours until the scalpel separated them ) but must communicate with the remaining tissue to decide what anatomical structures must be formed . It was shown recently that this long - range communication occurs via GJ - mediated electrical synapses ( Scemes et al . 2007 ; Marder , 2009 ; Pereda et al . 2013 ) , and works together with a bioelectric circuit that determines head vs . tail identity in each end ' s blastema ( Beane et al . 2011 , 2013 ) . Importantly , it was shown that inhibition of this gap junction - mediated communication , using octanol , results in worm fragments forming heads at bot"
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    The Journal of Physiology 06/2014; 592(Pt 11):2295-2305. DOI:10.1113/jphysiol.2014.271940
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    • "The mechanism of entry, and in some cases exit, is still not clear for either RNA or DNA although caveoli and pinocytosis seem to be implicated their entry into cells. As yet, there is no information as the possible rôles that connexins, innexins and pannexins might play in the intercellular movement of nuceic acids (Scemes et al. 2007; Nguyen et al. 2009). Both naked DNA and the newly-synthesised, spontaneously released DNA complex released into the blood can move to other parts of the organism and into host cells. "
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    • "Connexins (Cx) control intercellular communication by coordinating multicellular responses in organs, via chemical or electrical signals [1] [2] [3]. Six Cx subunits assemble into a connexon, which can exist as free, unopposed hemichannels or as head-by-head apposed hemichannels that form gap junctions [4] [5]. "
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    Biochemical and Biophysical Research Communications 01/2013; DOI:10.1016/j.bbrc.2013.01.066
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