Polycomb Silencing Mechanisms in Drosophila
This extract was created in the absence of an abstract.
Excerpt
Homeotic genes are a preeminent target for epigeneticmechanisms that program and maintain a chromatin state.The study of their function in Drosophila originally allowed the identification of Polycomb Group (PcG) genes,although we now know that PcG mechanisms regulatemany other genes. Homeotic genes must be expressed inspecific segmental domains of the Drosophila body planthroughout development. The expression domains are setin the earliest stages of embryonic development by transient regulators localized in specific regions of the embryo by maternal cues. Shortly after blastoderm, PcGcomplexes take over to maintain the repressed state inthose cells in which the target genes had not been activated in the first 3 hours of development. The descendants of these cells maintain this silent state of the targetgenes for the rest of development...
