Minding the Gaps - and the Junctions, Too
Platelets may be small, but their behavior in vivo is governed by molecular mechanisms every bit as complex as those in larger cells and new molecules that provide unexpected insights turn up with surprising regularity. One recent example is the connexin family member, Cx37 or GJA4. The role of Cx37 in platelets is examined in this issue by Vaiyapuri et al.1, but a related study by Angelillo-Scherer, et al.2 appeared here a year ago and both will be considered together. Cx37 is a member of a family of gap junction proteins that can assemble a comparatively non-selective channel when cells come into close contact with each other. These channels are large enough to allow free passage of soluble molecules such as cAMP, Ca++ and IP3 between cells. They are formed by the interaction of two Cx37 hemichannels on the surface of opposing cells. Hemichannels themselves can also pass small molecules, but with different specificities than the complete channel (see Kar, et al.3 for a recent review). (SELECT FULL TEXT TO CONTINUE)
- Received April 9, 2012.
- Accepted April 10, 2012.
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