Horizontal transmission of functionally diverse transposons is a major source of new introns

• 成果类型: Article
• 署名作者: Gozashti, Landen; Nakamoto, Anne; Russell, Shelbi; Corbett-Detig, Russell
• 署名单位: Harvard University; Harvard University; Howard Hughes Medical Institute; Harvard University; University of California System; University of California Santa Cruz; University of California System; University of California Santa Cruz
• 刊物名称: PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
• ISSN/ISSBN: 0027-11250
• DOI: 10.1073/pnas.2414761122
• 发表日期: 2025-05-27
• 关键词: gene-transfer; spliceosomal introns; dna; ELEMENTS; database; EVOLUTION; reveals; viruses; positions; expansion

摘要

Since the discovery of spliceosomal introns in eukaryotic genomes, the proximate molecular and evolutionary processes that generate new introns have remained a critical mystery. Specialized transposable elements (TEs), introners, are thought to be one of the major drivers of intron gain in diverse eukaryotes. However, the molecular mechanism(s) and evolutionary processes driving introner propagation within and between lineages remain elusive. Here, we analyze 8,716 genomes, revealing 1,093 introner families in 201 species spanning 1.7 billion years of evolution. Introners are derived from functionally diverse TEs including families of terminal-inverted-repeat DNA TEs, retrotransposons, cryptons, and helitrons as well as mobile elements with unknown molecular mechanisms. We identify eight cases where introners recently transferred between divergent host species and show that giant viruses that integrate into genomes may facilitate introner transfer across lineages. We propose that ongoing intron gain is primarily a consequence of TE activity in eukaryotes, thereby resolving a key mystery of genome structure evolution.