On the cover: Placement of connexins in the vessel and possible roles in mediating cell-cell interactions. Three modes of intercellular signaling are shown: (1) water-filled channel, (2) hemichannel, and (3) direct molecular signaling. This figure shows transcellular connexin-connexin signaling mediated by molecular interaction 3. This highlights the suggestion that other molecules, such as signaling kinases and ion channels, may be part of the gap junctional signaling complex. (See page 804.)