The cover shows panning for ion channel protein. The patch-clamp electrode is attached to a human embryonic kidney (HEK293) cell transiently expressing Kv1.3 ion channel and tyrosine kinase signaling proteins of interest. Because not all cells equally take up the cDNA-lipid complex during the transfection, red polypropylene beads are linked to an antibody that recognizes one of the expressed proteins so that the patch-clamper can identify a "good cell." For details see the article by Cook and Fadool, pages 13268-13280.