Hybrid exons evolved by coupling transcription initiation and splicing at the nucleotide level.

ABSTRACT: Exons within transcripts are traditionally classified as first, internal or last exons, each governed by different regulatory mechanisms. We recently described the widespread usage of 'hybrid' exons that serve as terminal or internal exons in different transcripts. Here, we employ an interpretable deep learning pipeline to dissect the sequence features governing the co-regulation of transcription initiation and splicing in hybrid exons. Using ENCODE data from human tissues, we identified 80 000 hybrid first-internal exons. These exons often possess a relaxed chromatin state, allowing transcription initiation within the gene body. Interestingly, transcription start sites of hybrid exons are typically centered at the 3' splice site, suggesting tight coupling between splicing and transcriptio

SUBMITTER: Mick ST 

PROVIDER: S-EPMC11797052 | biostudies-literature | 2025 Jan

REPOSITORIES: biostudies-literature