TIME OUT - DEVELOPMENTAL REGULATION OF HETEROCHROMATIC SILENCING IN DROSOPHILA

Transcriptional silencing by heterochromatin represents a model for de velopmental gene silencing. Current models of heterochromatin envision DNA-protein complexes that prevent access by euchromatic transcriptio n factors. Here, we summarize the evidence that heterochromatin acts a t the chromatin level to silence genes and the status of current model s of heterochromatin silencing, and we highlight some recent progress in understanding the composition and regulation of heterochromatin in Drosophila.