| upstream activation site | A DNA sequence that regulates transcription like an enhancer but does notwork if its located downstream from a promoter. (09 Oct 1997) |
|---|---|
| fragile site | Places on chromosomes that tend to break more often than other places. These places also tend to be where chromosomal translocations (a type of chromosomal mutation) occur. (09 Oct 1997) |
| ligand binding site | The site on a protein's surface that binds a ligand; equivalent to the active site if the ligand is the substrate of an enzyme. (05 Mar 2000) |