Molecular function

GO:0001104, GO:0016455

transcription cofactor activity, transcriptional co-regulator

A transcription regulator activity that modulates the transcription of specific gene sets via binding to a DNA-bound DNA-binding transcription factor, either on its own or as part of a complex. Coregulators often act by altering chromatin structure and modifications. For example, one class of transcription coregulators modifies chromatin structure through covalent modification of histones. A second class remodels the conformation of chromatin in an ATP-dependent fashion. A third class modulates interactions of DNA-bound DNA-binding transcription factors with other transcription coregulators.

RNA polymerase II transcriptional cofactor activity

Usage guidance: Most transcription coregulators do not bind DNA. Those that do usually bind DNA either in a non-specific or non-direct manner. If a protein binds DNA specifically, consider annotating to GO:0003700 DNA binding transcription factor activity.