Cover photograph (Copyright © 2003, American Society for Microbiology. All Rights Reserved.): Binding of Drosophila Polycomblike (PCL) to the Ubx Polycomb response element (PRE) in vivo. The binding sites of PCL (red) on the distal portion of chromosome arm 3L (blue) are shown in a wild-type larva (top) and in a transformant (bottom) containing the 670-bp PstI/NdeI fragment of the Ubx PRE inserted at 65B. A landmark site at 65D which is bound by PCL is indicated by a white line. (See related article on p. 3352.)