Filling in the gap

ow do you construct a channel between cells ? The first step in answering this question was to isolate the components of one type of channel—the gap junction. H Daniel Goodenough had been pursuing gap junction proteins since his days as a graduate student in the mid-1960s with Jean-Paul Revel, who helped discover the structures (Revel and Karnovsky, 1967; see “Defining gap junctions” JCB 169:379). In 1972, Goodenough demonstrated that gap junctions could be purified biochemically (Goodenough and Stoeckenius, 1972). By the mid-1970s, when Goodenough had his own lab at Harvard Medical School (Boston, MA), the field was struggling with spotty antibodies in its efforts to identify which proteins were forming the junctions. When then graduate student David Paul joined Goodenough, they strove to make a clean enough preparation of rat liver gap junctions to generate a better antibody—hopefully one that could be used for expression cloning. Paul says there was nothing “technically miraculous” about their approach,