DNA polymerase III holoenzyme assembles in stages, generating an enzyme complex that synthesizes the DNA of both new strands.\

Binding to DNA changes the conformation of the site on B that binds to the clamp loader, and as a result it now has a high affinity for the core polymerase.

First the clamp loader uses hydrolysis ofATPtobindbeta subunits to a template primercomplex.

Binding to DNA changes the conformation of the site on B that binds to the clamp loader, and as a result it now has a high affinity for the core polymerase.

tau. dimer binds to the core polymerase, and provides a dimerization function thatbinds a second core polymerase (associated with another B2 

TLS Online TPP Program

#Id: 2646

#Unit 13. Methods in Biology

A G-less cassette, or stretch of nucleotides lacking guanines in the nontemplate strand, is inserted just downstream of the promoter. This template is transcribed in vitro with CTP, ATP, and UTP, one of which is labeled, but no GTP.

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#Id: 2647

#Unit 13. Methods in Biology

In G-less cassette, transcription will stop at the end of the cassette where the first G is required, yielding an aborted transcript of predictable size (based on the size of the G-less cassette, which is usually a few hundred base pairs long).

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#Id: 2648

#Unit 13. Methods in Biology

Primer extension, S1 mapping, and Northern blotting are useful for determining the concentrations of specific transcripts in a cell at a given time, but they do not necessarily tell us the rates of synthesis of the transcripts.

TLS Online TPP Program

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#Unit 13. Methods in Biology

In Run-on transcription- the RNA polymerase that has already initiated transcription in vivo simply “runs on” or continues to elongate the same RNA chains. 

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#Unit 13. Methods in Biology

The run-on reaction is usually done in the presence of labeled nucleotides so the products will be labeled.

TLS Online TPP Program

#Id: 2737

#Unit 13. Methods in Biology

Nuclear run-on transcription is a way of ascertaining which genes are active in a given cell by allowing transcription of these genes to continue in isolated nuclei.