DNA Transcriptio1 - hairpin loop. As you can see, the...

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DNA Transcription Termination RNA synthesis will continue along the DNA template strand until the polymerase encounters a signal that tells it to stop, or terminate, transcription. In prokaryotes, this signal can take two forms, rho-independent and rho-dependent. Rho-independent Terminator The rho-independent terminator is the more simple of the two systems and as a result is also called simple termination. The rho-independent signal is found on the DNA template strand and consists of a region that contains a section that is then repeated a few base pairs away in the inverted sequence. Figure %: Rho-Independent Terminator As is shown in the figure, the patch is followed by a short string of adenines. When this stretch is transcribed into an RNA sequence, the RNA can fold back and base pair with itself forming a
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Unformatted text preview: hairpin loop. As you can see, the string of adenines in the DNA sequence are transcribed into uracils in the RNA sequence. Because the uracil bases will only pair weakly with the adenines, the RNA chain can easily be released from the DNA template, terminating transcription. Rho-Dependent Terminator The rho-dependent terminator received its name because it is dependent on a specific protein called a rho factor. The rho factor is thought to bind to the end of the RNA chain and slide along the strand towards the open complex bubble. When the factor catches the polymerase, it causes the termination of transcription. The mechanism of this termination is unclear, but the rho factor could in some way pull the polymerase complex off of the DNA strand....
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DNA Transcriptio1 - hairpin loop. As you can see, the...

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