Year: 2026
Type: preprint
Abstract: Two rounds of whole-genome duplication (2R-WGD) in the vertebrate lineage are thought to have driven gene diversification. Mammals have four genes encoding five nebulin superfamily proteins ( LASP1 , LASP2/NEBL , NEB , and NRAP ) hypothesised to have arisen from invertebrate LASP via WGD. Here, we examined the evolutionary fate of the nebulin superfamily after an additional WGD, teleost-specific genome duplication (TGD). Genome and transcriptome analysis of zebrafish ( Danio rerio ) and medaka ( Oryzias latipes ), of which the complete genomes were recently determined, showed only lasp family genes retained duplicate copies. Zebrafish retained two LASP2/NEBL -derived ohnologs; one ( LASP2L ) had been misidentified as a nebulette gene in the Zebrafish Information Network (ZFIN) despite lacking nebulette-specific exons. Another ( LASP2/NEBL ) is newly identified in this study because it lies in a newly determined region of the latest genome assembly. Contrastingly, medaka retained two LASP1 ohnologs and one LASP2/NEBL . The duplicated lasp family proteins showed overlapping and specific tissue expression patterns. We confirmed all three zebrafish lasp proteins bound actin and co-localized with actin-rich structures when ectopically expressed in cultured fibroblasts. This supports that TGD-derived lasp duplicates underwent lineage-specific retention and expression divergence in teleosts whilst conserving core actin-binding properties.
Language: English
Subfield: Genetics
Domain: Life Sciences
Open Access status: green
OpenAlex ID: W7221113705