[J. Kirkband]

When an RNA transcript is first made in a eukaryotic cell, it is considered a pre-mRNA and must be processed into a messenger RNA (mRNA). A 5’ cap is added to the beginning of the RNA transcript, and a 3’ poly-A tail is added to the end. In splicing, some sections of the RNA transcript (introns) are removed, and the remaining sections (exons) are stuck back together.

So yes, all RNAs start out as primary transcripts before they can be translated into proteins.

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