Transposon insertion causes <i>ctnnb2</i> transcript instability that results in the maternal effect zebrafish <i>ichabod</i> (<i>ich</i>) mutation.

ABSTRACT: The maternal-effect mutation ichabod (ich) results in ventralized zebrafish embryos due to impaired induction of the dorsal canonical Wnt-signaling pathway. While previous studies linked the phenotype to reduced ctnnb2 transcript levels, the causative mutation remained unidentified. Using long-read sequencing, we discovered that the ich phenotype stems from the insertion of a non-autonomous CMC-Enhancer/Suppressor-mutator (CMC-EnSpm) transposon in the 3'UTR of the gene. Through reporter assays, we demonstrate that while wild type ctnnb2 mRNAs exhibit remarkably high stability throughout the early stages of development, the insertion of the transposon dramatically reduces transcript stability. Genome-wide mapping of the CMC-EnSpm transposons across multiple zebra

SUBMITTER: Varga Z 

PROVIDER: S-EPMC11908130 | biostudies-literature | 2025 Mar

REPOSITORIES: biostudies-literature