Taxonomy of introns and the evolution of minor introns

Olthof, AM; Schwoerer, CF; Girardini, KN; Weber, AL; Doggett, K; Mieruszynski, S; Heath, JK; Moore, TE; Biran, J; Kanadia, RN

Author(s): Olthof, AM; Schwoerer, CF; Girardini, KN; Weber, AL; Doggett, K; Mieruszynski, S; Heath, JK; Moore, TE; Biran, J; Kanadia, RN;
Details: Publication Year 2024-06-29,Volume 52,Issue #15,Page 9247-9266
Journal Title: Nucleic Acids Research
Abstract: Classification of introns, which is crucial to understanding their evolution and splicing, has historically been binary and has resulted in the naming of major and minor introns that are spliced by their namesake spliceosome. However, a broad range of intron consensus sequences exist, leading us to here reclassify introns as minor, minor-like, hybrid, major-like, major and non-canonical introns in 263 species across six eukaryotic supergroups. Through intron orthology analysis, we discovered that minor-like introns are a transitory node for intron conversion across evolution. Despite close resemblance of their consensus sequences to minor introns, these introns possess an AG dinucleotide at the -1 and -2 position of the 5' splice site, a salient feature of major introns. Through combined analysis of CoLa-seq, CLIP-seq for major and minor spliceosome components, and RNAseq from samples in which the minor spliceosome is inhibited we found that minor-like introns are also an intermediate class from a splicing mechanism perspective. Importantly, this analysis has provided insight into the sequence elements that have evolved to make minor-like introns amenable to recognition by both minor and major spliceosome components. We hope that this revised intron classification provides a new framework to study intron evolution and splicing.
Publisher: Oxford Academic
Keywords: *Introns/genetics; *Evolution, Molecular; *Spliceosomes/genetics; *RNA Splicing; Humans; RNA Splice Sites; Animals; Consensus Sequence; Eukaryota/genetics/classification; Base Sequence
Research Division(s): Inflammation; Epigenetics And Development; Epigenetics and Development
PubMed ID: 38943346
Publisher's Version: https://doi.org/10.1093/nar/gkae550
Open Access at Publisher's Site: https://doi.org/10.1093/nar/gkae550
Terms of Use/Rights Notice: Refer to copyright notice on published article.

Creation Date: 2024-07-03 09:58:50

Last Modified: 2024-09-02 10:58:36