Transcription is the process by which genetic information in DNA is transcribed into RNA. The sequence of steps in transcription is as follows:
1. Transcription bubble formation (A): The process begins with the unwinding of DNA, forming a transcription bubble. This exposes the template strand for RNA synthesis.
2. Phosphorylation of CTD tail (B): The C-terminal domain (CTD) of RNA polymerase II undergoes phosphorylation. This modification is essential for transitioning the polymerase from the initiation phase to elongation.
3. Recruitment of elongation factors (C): During the elongation phase, various elongation factors are recruited to stabilize the transcription complex and assist RNA polymerase in synthesizing the RNA strand.
4. Dephosphorylation of CTD tail (D): At the end of transcription, the CTD tail is dephosphorylated, facilitating the termination of transcription and release of the RNA transcript.
List I | List II |
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(A) Radiation hybrid mapping | (I) DNA can be cut into large fragments and circularized for use in chromosome walking |
(B) Sequence tagged site (STS) mapping | (II) Useful for cloning of overlapping DNA fragments (restricted to about 200 kb) |
(C) Chromosome jumping | (III) Fragment genome into large pieces and locate markers and genes |
(D) Chromosome walking | (IV) Applicable to any part of DNA sequence if some sequence information is available |