The two H2A.H2B dimers each associate with 30 bp of DNA on either side of the central 60 bp of DNA bound by H3 and H4.

TLS Online TPP Program

#Id: 6461

#Unit 3. Fundamental Processes

A significant difference between the transcription of eukaryotic and prokaryotic RNAs is that in bacteria, transcription takes place on  RNA polymerase III synthesizes small RNAs in the nucleoplasm

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#Id: 6462

#Unit 3. Fundamental Processes

A typical gene transcribed by RNA polymerase II has a promoter that extends upstream from the site where transcription is initiated.

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#Id: 6463

#Unit 3. Fundamental Processes

A regulatory site that binds more negative regulators than positive regulators to control transcription is called a silencer.

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#Id: 6464

#Unit 3. Fundamental Processes

Promoters that are constitutively expressed and needed in all cells (their genes are sometimes called housekeeping genes) have upstream sequence elements that are recognized by ubiquitous activators.

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#Id: 6465

#Unit 3. Fundamental Processes

Proteins bound at enhancer elements interact with proteins bound at promoter elements via DNA looping, very often through intermediates called coactivators.

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#Id: 6466

#Unit 3. Fundamental Processes

Eukaryotic transcription is most often under positive regulation: A transcription factor is provided under tissue-specific control to activate a promoter or set of promoters that contain a common target sequence.