DESCRIPTION: (Adapted from abstract.) Homeotic genes are expressed in restricted domains along the body axis of the fruitfly, Drosophila melanogaster. Transcriptional silencing plants the dominant role in establishing and maintaining the restricted domains of expression that are observed. The investigators propose to examine the molecular mechanism of silencing by the silencing maintenance element MCP from the Abd-B gene of the biothorax complex. The first aim of this proposal is to ask if positional information is required by the MCP element for maintaining silenced domains, or if they are propagated without such cues. The second aim is to identify the minimal sequence required for maintenance of the silencing. The third aim is to identify proteins that bind to the MCP element.