Annotated Bibliography On Prokaryotic Transcription Essay example

1612 Words Nov 30th, 2016 7 Pages
Prokaryotic transcription is the process from DNA to mRNA. DNA is used as the blueprint during transcription and aids in the formation of a coded RNA sequence, which is later translated into proteins. Transcription includes, a coding strand that has a promoter sequence embedded in it from the 5’ to the 3’ end. The promoter controls the transcription start site, 8 to 10 nucleotides downstream from the -10 sequence. Along with the template strand also known as the complimentary strand to the coding strand, starting from 3’ to 5’ end. Transcription is composed of 3 stages, initiation, elongation, and termination. Initiation starts when the sigma factor binds to RNA polymerase and together they bind to the promoter sequence, which creates a closed complex called initiation complex after it binds to the promoter. The initiation complex is made up of the promoter (-10 & -35), sigma factor, and RNA polymerase bound to the DNA template strand. This complex starts breaking the Hydrogen bonds between Adenine-Thymine & Cytosine-Guanine, converting the closed complex into an open complex. Without the sigma factor RNA polymerase cannot bind to the promoter, and without binding it cannot synthesize a new mRNA strand. Likewise, during elongation RNA polymerase begins adding ribonucleotides to the 3’ template strand after it proceeds to the +1 transcription start site. Upon the completion of transcribing about 15 nucleotides a change must occur to RNA polymerase, and the sigma complex must…

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