What is the role of transcription factors and cofactors in gene regulation and how do they interact with RNA polymerase II?

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Multiple Choice

What is the role of transcription factors and cofactors in gene regulation and how do they interact with RNA polymerase II?

Transcription factors recognize specific DNA sequences in promoters and enhancers and recruit RNA polymerase II by assembling the general transcription factors into the preinitiation complex, effectively guiding Pol II to start site and activating transcription. Cofactors—often not binding DNA directly—act as bridges and chromatin modifiers: they remodel or chemically modify histones to loosen chromatin and create an accessible environment, and they help assemble or stabilize the transcriptional machinery, including Pol II, at the promoter. Through these coordinated actions, transcription factors and cofactors control when and how much a gene is transcribed in response to signals. Note that these factors are not degraders of mRNA, nor do they recruit ribosomes for translation; their role is at the level of transcription initiation and chromatin regulation.

Transcription factors recognize specific DNA sequences in promoters and enhancers and recruit RNA polymerase II by assembling the general transcription factors into the preinitiation complex, effectively guiding Pol II to start site and activating transcription. Cofactors—often not binding DNA directly—act as bridges and chromatin modifiers: they remodel or chemically modify histones to loosen chromatin and create an accessible environment, and they help assemble or stabilize the transcriptional machinery, including Pol II, at the promoter. Through these coordinated actions, transcription factors and cofactors control when and how much a gene is transcribed in response to signals. Note that these factors are not degraders of mRNA, nor do they recruit ribosomes for translation; their role is at the level of transcription initiation and chromatin regulation.

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