Cover photograph (Copyright © 2002, American Society for Microbiology. All Rights Reserved.): Meiotic prophase analysis in spermatocytes. Germ cell spreads were stained with DAPI to visualize DNA (blue) and antibodies to SCP3 (green) and SUMO-1 (red). SUMO-1 localizes to the sex body, allowing identification of the paired X and Y chromosomes. (See related article in June 2002: issue 7, vol. 22, p. 2294.)