Protein phosphorylation and hydrogen ions modulate calcium-induced closure of gap junction channels
| Autor: | F. Ramon, R. O. Arellano, A. Rivera |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 1990 |
| Předmět: |
Calmodulin
Biophysics chemistry.chemical_element Astacoidea Calcium In Vitro Techniques Cell junction Calcium in biology Ion Channels Calcium Chloride Animals Protein phosphorylation Egtazic Acid Ion channel biology Tight junction Chemistry Electric Conductivity Hydrogen-Ion Concentration Axons Cell biology Intercellular Junctions biology.protein Phosphorylation Ganglia Protein Kinases Research Article |
| Popis: | The regulation of the cell-to-cell pathway formed by gap junctions seems to involve the interaction of the junctional channels with either calcium or hydrogen ions, as well as protein phosphorylation and calmodulin. These mechanisms of junctional regulation have been considered to act independently on specific sites of the gap junction protein; however, the possibility that they may be interrelated has not been adequately explored mainly due to the difficulties involved in simultaneous measurement of intracellular cations and protein phosphorylation. To further understanding of mechanisms regulating gap junctions, we have internally perfused coupled lateral axons from crayfish with solutions containing different calcium and hydrogen concentrations under conditions favoring phosphorylation, while monitoring the junctional conductance. We found that calcium ions regulate cell communication probably through a direct interaction with the channel protein. Phosphorylation and low pH do not alter junctional conductance themselves, but appear only to modulate the effects of calcium, possibly by altering the affinity of the channel for calcium. We propose that a combination of free intracellular calcium and protein phosphorylation form an important physiological mechanism regulating intercellular communication. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|