Different roles fulfilled by the same transcription factors. Steroid receptors (white shapes) bind to their response elements (REs) after being activated by their ligands (black dots). (a) Binding to different REs recruits a common cofactor and an element-specific cofactor (black octagon and grey shapes, resp.) (b) Binding to adjacent RE recruits a bridging factor. (c) Binding to negative REs recruits corepressors [18].
