Skip to main content
U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Intron and Exons

Published

Author(s)

Arlin B. Stoltzfus

Abstract

An intron (or intervening sequence) is a segment of RNA excised from a gene transcript, with concomitant ligation of flanking segments called exons. Introns of some type are found in every kingdom of cellular life, and also in viruses, bacteriophages and plasmids. The spliceosomal introns are the most familiar class of introns, and are found primarily in protein-coding genes in the eukaryotic nucleus. For group I and group II self-splicing introns, the introns RNA plays a primary role in the biochemistry of splicing, in some cases being sufficient for splicing in vitro. Introns apparently have no general role in gene expression, through in specific cases, introns and splicing figure importantly in developmental gene expression.
Citation
Encyclopedia of Genetics

Keywords

exon, intron, splicing

Citation

Stoltzfus, A. (2001), Intron and Exons, Encyclopedia of Genetics (Accessed December 13, 2024)

Issues

If you have any questions about this publication or are having problems accessing it, please contact reflib@nist.gov.

Created October 16, 2001, Updated February 19, 2017