This wiki is being tested. With FB2013_01, released January 23rd, 2013, FlyBase is testing this wiki for gene summarization as part of our community curation effort. A more formal release is planned for FB2013_03, scheduled May 3rd, 2013. Please help us by sending in feedback using this form.
Ahmad and Henikoff, 2001, Cell 104(6): 839--847
| Ahmad and Henikoff, 2001, Cell 104(6): 839--847 | |
|---|---|
| FlyBase Identifier | FBrf0135679 |
| FlyBase URL | http://flybase.org/reports/FBrf0135679.html |
| Publication Type | paper |
| Publication Year | 2001 |
| PubMed ID | 11290322 |
| PubMed URL | http://www.ncbi.nlm.nih.gov/pubmed/11290322 |
Title
Modulation of a transcription factor counteracts heterochromatic gene silencing in Drosophila.
Abstract
Variegation is a common feature of gene silencing phenomena, yet the basis for stochastic on/off expression is unknown. We used a conditional system that allows probing of heterochromatin at a reporter GFP gene by altering GAL4 transcription factor levels during Drosophila eye development. Surprisingly, the frequency of gene silencing is exquisitely sensitive to GAL4 levels, as though binding site occupancy affects the silenced state. The silent state is plastic, as spontaneous derepression occasionally occurs in both mitotically active and differentiating cells. By simultaneously assaying expression of a nearby gene, we further show that the size of an activated region within heterochromatin is small. We propose that variegation occurs because heterochromatin inhibits the transient exposure of factor binding sites.
Genes from Reference
| Gene(s) | Dmel\w |
|---|