PMID- 15955306
OWN - NLM
STAT- MEDLINE
DCOM- 20050728
LR  - 20181113
IS  - 0006-3002 (Print)
IS  - 0006-3002 (Linking)
VI  - 1711
IP  - 2
DP  - 2005 Jun 10
TI  - Connexin-based gap junction hemichannels: gating mechanisms.
PG  - 215-24
AB  - Connexins (Cxs) form hemichannels and gap junction channels. Each gap junction 
      channel is composed of two hemichannels, also termed connexons, one from each of 
      the coupled cells. Hemichannels are hexamers assembled in the ER, the Golgi, or a 
      post Golgi compartment. They are transported to the cell surface in vesicles and 
      inserted by vesicle fusion, and then dock with a hemichannel in an apposed 
      membrane to form a cell-cell channel. It was thought that hemichannels should 
      remain closed until docking with another hemichannel because of the leak they 
      would provide if their permeability and conductance were like those of their 
      corresponding cell-cell channels. Now it is clear that hemichannels formed by a 
      number of different connexins can open in at least some cells with a finite if 
      low probability, and that their opening can be modulated under various 
      physiological and pathological conditions. Hemichannels open in different kinds 
      of cells in culture with conductance and permeability properties predictable from 
      those of the corresponding gap junction channels. Cx43 hemichannels are 
      preferentially closed in cultured cells under resting conditions, but their open 
      probability can be increased by the application of positive voltages and by 
      changes in protein phosphorylation and/or redox state. In addition, increased 
      activity can result from the recruitment of hemichannels to the plasma membrane 
      as seen in metabolically inhibited astrocytes. Mutations of connexins that 
      increase hemichannel open probability may explain cellular degeneration in 
      several hereditary diseases. Taken together, the data indicate that hemichannels 
      are gated by multiple mechanisms that independently or cooperatively affect their 
      open probability under physiological as well as pathological conditions.
FAU - Saez, Juan C
AU  - Saez JC
AD  - Departamento de Ciencias Fisiologicas, Pontificia Universidad Catolica de Chile, 
      Santiago, Chile. jsaez@bio.puc.cl
FAU - Retamal, Mauricio A
AU  - Retamal MA
FAU - Basilio, Daniel
AU  - Basilio D
FAU - Bukauskas, Feliksas F
AU  - Bukauskas FF
FAU - Bennett, Michael V L
AU  - Bennett MV
LA  - eng
GR  - NS36706/NS/NINDS NIH HHS/United States
GR  - NS45837/NS/NINDS NIH HHS/United States
GR  - R21 NS045837/NS/NINDS NIH HHS/United States
GR  - R01 NS036706/NS/NINDS NIH HHS/United States
GR  - R01 NS036706-06/NS/NINDS NIH HHS/United States
GR  - R01 NS036706-09/NS/NINDS NIH HHS/United States
PT  - Journal Article
PT  - Research Support, N.I.H., Extramural
PT  - Research Support, Non-U.S. Gov't
PT  - Research Support, U.S. Gov't, P.H.S.
PT  - Review
DEP - 20050302
PL  - Netherlands
TA  - Biochim Biophys Acta
JT  - Biochimica et biophysica acta
JID - 0217513
RN  - 0 (Connexin 43)
RN  - 0 (Connexins)
RN  - 0 (Ion Channels)
SB  - IM
MH  - Animals
MH  - Connexin 43/physiology
MH  - Connexins/*physiology
MH  - Gap Junctions/*physiology
MH  - Humans
MH  - Ion Channel Gating/*physiology
MH  - Ion Channels/*physiology
MH  - Oxidation-Reduction
MH  - Phosphorylation
PMC - PMC3617572
MID - NIHMS122258
EDAT- 2005/06/16 09:00
MHDA- 2005/07/29 09:00
PMCR- 2013/04/05
CRDT- 2005/06/16 09:00
PHST- 2004/11/02 00:00 [received]
PHST- 2005/01/20 00:00 [revised]
PHST- 2005/01/26 00:00 [accepted]
PHST- 2005/06/16 09:00 [pubmed]
PHST- 2005/07/29 09:00 [medline]
PHST- 2005/06/16 09:00 [entrez]
PHST- 2013/04/05 00:00 [pmc-release]
AID - S0005-2736(05)00052-0 [pii]
AID - 10.1016/j.bbamem.2005.01.014 [doi]
PST - ppublish
SO  - Biochim Biophys Acta. 2005 Jun 10;1711(2):215-24. doi: 
      10.1016/j.bbamem.2005.01.014. Epub 2005 Mar 2.