During transcription of mRNA, is helicase needed to separate the two strands of the DNA double helix?
Transcription is the process used to make RNA based off of a DNA template. Transcription is used to make all types of RNA, including messenger RNA, transfer RNA, and ribosomal RNA. The process for each of these is similar.
Answer and Explanation:
It's easy to think of RNA transcription as a very straightforward process: DNA opens, nucleotides come in, RNA is made. While this is mostly true, there are actually a lot of players involved in helping make this process happen smoothly.
RNA polymerase is an essential protein for transcription, but it's actually not just one single piece. There are actually several proteins, called transcription factors, that join together to make something called the RNA polymerase holoenzyme (essentially, whole enzyme). One of the transcription factors that makes up this holoenzyme acts a helicase enzyme, separating the two strands of DNA.
Basically, helicase is already a part of the RNA polymerase enzyme. Therefore, a separate helicase is not required for transcription of mRNA.
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fromChapter 9 / Lesson 2
Learn about mRNA transcription. Discover where and how DNA is transcribed into RNA in prokaryotes and eukaryotes, and examine the final product of transcription.