In summary, vascular connexins are central to the structural and functional organization of the vascular bed. Functionally, they are overwhelmingly important for normal vascular development and in the regulation of vascular tone. The formation of gap-junctional channels is a complex process that is subject to plasticity and depends upon cell type and connexin subtype specificity. However, several questions remain. For instance, more needs to be understood with respect to the role of vascular connexins in pathological states. This role may be extensive and highly facilitatory to disease progression, especially in the vascular involvement in inflammation, in atherosclerotic plaque formation, and in abnormalities of blood coagulation. The emerging role of gap junctions in the consideration of vascular patho-biology promises to be fertile ground for future research.
Connexin: Channel-forming transmembrane protein subunit. A complete gap junction channel consists of six connexins in one cell pairing with six connexins in an adjacent cell that allow direct transfer of small cyto-plasmic molecules from one cell to an adjacent cell.
Gap junction: Originally defined by electron microscopy as a class of cell-cell contact sites with a uniform ~16-nm "gap" between the cells as opposed to tight junctions that show no gap. Gap junctions consist of an array of connexin-based channels that mediate cell-cell communication.
Heteromeric: A gap junction channel composed of two or more different types of connexins completely intermixed.
Heterotypic: Head-to-head interaction between one type of connexin in one cell and a different type of connexin in an adjacent cell.
Homomeric: A gap junction channel composed of a single type of connexin.
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Dr. Koval's laboratory studies the molecular mechanisms of membrane protein assembly and roles for intercellular communication in regulating pulmonary function. His work on gap junctions started more than a decade ago and is supported by grants from the NIH and American Heart Association.
Dr. Bhattacharya's laboratory investigates intercellular connectivity and coordination in proinflammatory signaling in microvessels. Using lung inflammation as a model, the Bhattacharya group has developed optical imaging methods to quantify signaling mechanisms in cells in situ.
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