pre-mRNA

genetics

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July 21, 2026

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In genetics, transcription is the process of synthesizing RNA from DNA. This is the first step in gene expression, where genetic information flows from DNA to RNA, and then to protein.12

In eukaryotes, the initial product of transcription is called pre-mRNA. This pre-mRNA molecule is an exact copy of the gene but contains intervening sequences called introns that must be removed through a process called RNA splicing. After splicing and other modifications, the mature mRNA is ready to be transported to the cytoplasm for translation, where its code is used to build proteins. Unlike the stable DNA, RNA is unstable and is continuously broken down and replaced, allowing cells to alter their protein synthesis patterns.32

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transcription
…of transcription is called a pre-mRNA. Pre-mRNA is extensively edited through splicing before the mature mRNA is produced and ready for translation by the ribosome, the cellular organelle that serves as the site of protein synthesis. Transcription of any one gene takes place at the chromosomal location of that gene,…
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…of transcription is called a pre-mRNA. Pre-mRNA is extensively edited through splicing before the mature mRNA is produced and ready for translation by the ribosome, the cellular organelle that serves as the site of protein synthesis. Transcription of any one gene takes place at the chromosomal location of that gene,…
Read More