Pioneer factors

(a) Comparison with nonpioneer transcription factors. (b) Attributes of pioneer factors(a) Comparison with nonpioneer transcription factors. (b) Attributes of pioneer factors

(a) Comparison with other transcription factors Most transcription factors Pioneer transcription factors cannot access their binding can access their binding sites sites in heterochromatin in heterochromatin. (b) Attributes W Partially bound, inactive enhancer module + additional activators for induction Fully bound, active enhancer module Can have an active role in Can have a role poising inducible openinq heterchromatin. qenes for rapid induction.