Coding region: Difference between revisions

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Revision as of 17:53, 30 May 2021

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== Structure and function ==

[[File:Coding Region in DNA.png|thumb|398x398px|'''Transcription''': RNA Polymerase (RNAP) uses a template DNA strand and begins coding at the promoter sequence (green) and ends at the terminator sequence (red) in order to encompass the entire coding region into the product pre-mRNA (teal). ''[IThe havepre-mRNA ais doubt if thepolymerised 5' andto 3' endand arethe showntemplate incorrectlyDNA inread this3' figure]'to 5']] [[File:Transcription label en.jpg|thumb|An electron-micrograph of DNA strands decorated by hundreds of RNAP molecules too small to be resolved. Each RNAP is transcribing an RNA strand, which can be seen branching off from the DNA. "Begin" indicates the 3' end of the DNA, where RNAP initiates transcription; "End" indicates the 5' end, where the longer RNA molecules are completely transcribed.]]

In [[DNA]], the coding region is flanked by the [[Promoter (genetics)|promoter sequence]] on the 5' end of the [[template strand]] and the termination sequence on the 3' end. During [[Transcription (biology)|transcription]], the [[RNA Polymerase|RNA Polymerase (RNAP)]] binds to the promoter sequence and moves along the template strand to the coding region. RNAP then adds RNA [[nucleotide]]s complementary to the coding region in order to form the [[mRNA]], substituting [[uracil]] in place of [[thymine]].<ref name=":2">Overview of transcription. (n.d.). Retrieved from <nowiki>https://www.khanacademy.org/science/biology/gene-expression-central-dogma/transcription-of-dna-into-rna/a/overview-of-transcription</nowiki>.</ref> This continues until the RNAP reaches the termination sequence.<ref name=":2" />