Cover picture: Inositol trisphosphate receptors (IP₃Rs,type 1; in green) in the I band of the sarcoplasmic reticulum (cross striations) and in a motor end plate region from dissociated mouse diaphragm muscle. A cluster of nuclei (blue) encircled by membrane of the postsynaptic gutter, marked by alpha-bungarotoxin labeling of acetylcholine receptors (AChR; in red), marks the position of the motor end plate. The overlap of IP₃Rs and AChRs leads to the orange tint of the AChR staining. There are some nuclei above the motor end plate region that are surrounded by IP₃Rs;these we identify as belonging to muscle satellite cells. A heavily stained cell, which we identify as a Schwann cell, is visible just below the motor end plate. For details, see the article by Powell in this issue (pages 8185–8192).