Introns

Definition

Introns are non-coding sequences in a gene that are removed during RNA splicing. They do not encode protein sequences and are found in eukaryotic genomes.

5 Must Know Facts For Your Next Test

1. Introns are transcribed into pre-mRNA but are removed before translation.
2. RNA splicing is the process that removes introns from pre-mRNA.
3. Introns can play roles in gene expression regulation and alternative splicing.
4. Eukaryotic genes typically contain more introns than prokaryotic genes, which rarely have them.
5. Intron-exon boundaries are recognized by specific nucleotide sequences.

Review Questions

• What is the primary function of introns?
• How are introns removed from pre-mRNA?
• What roles other than coding for proteins might introns play?

Related terms

Exon: Coding sequences in a gene that remain in mRNA after splicing.

Pre-mRNA: The initial transcript that includes both exons and introns.

Spliceosome: A complex of proteins and RNA molecules responsible for removing introns from pre-mRNA.