Introns

Definition

Introns are non-coding sequences of DNA within a gene that are removed during RNA splicing. They do not encode protein sequences and are transcribed into pre-mRNA but not translated into proteins.

5 Must Know Facts For Your Next Test

1. Introns are found in eukaryotic genes but are generally absent in prokaryotes.
2. During RNA splicing, introns are removed from the pre-mRNA, and exons are joined together to form mature mRNA.
3. The presence of introns allows for alternative splicing, which can produce multiple protein variants from a single gene.
4. Introns often contain regulatory elements that can influence gene expression.
5. Mutations in intron regions can affect splicing and lead to various genetic disorders.

Review Questions

Related terms

Exon: Coding sequences of DNA within a gene that remain in the mRNA after RNA splicing and code for proteins.

RNA Splicing: The process by which introns are removed from pre-mRNA and exons are joined to form mature mRNA.

Alternative Splicing: A mechanism by which different combinations of exons are joined together to produce multiple mRNA variants from a single gene.