Title | A duplicated copy of id2b is an unusual sex-determining candidate gene on the Y chromosome of arapaima (Arapaima gigas). |
Publication Type | Journal Article |
Year of Publication | 2021 |
Authors | Adolfi, MC, Du, K, Kneitz, S, Cabau, C, Zahm, M, Klopp, C, Feron, R, Paixão, RV, Varela, ES, de Almeida, FL, de Oliveira, MA, Nóbrega, RH, Lopez-Roques, C, Iampietro, C, Lluch, J, Kloas, W, Wuertz, S, Schaefer, F, Stöck, M, Guiguen, Y, Schartl, M |
Journal | Sci Rep |
Volume | 11 |
Issue | 1 |
Pagination | 21544 |
Date Published | 2021 Nov 03 |
ISSN | 2045-2322 |
Abstract | Arapaima gigas is one of the largest freshwater fish species of high ecological and economic importance. Overfishing and habitat destruction are severe threats to the remaining wild populations. By incorporating a chromosomal Hi-C contact map, we improved the arapaima genome assembly to chromosome-level, revealing an unexpected high degree of chromosome rearrangements during evolution of the bonytongues (Osteoglossiformes). Combining this new assembly with pool-sequencing of male and female genomes, we identified id2bbY, a duplicated copy of the inhibitor of DNA binding 2b (id2b) gene on the Y chromosome as candidate male sex-determining gene. A PCR-test for id2bbY was developed, demonstrating that this gene is a reliable male-specific marker for genotyping. Expression analyses showed that this gene is expressed in juvenile male gonads. Its paralog, id2ba, exhibits a male-biased expression in immature gonads. Transcriptome analyses and protein structure predictions confirm id2bbY as a prime candidate for the master sex-determiner. Acting through the TGFβ signaling pathway, id2bbY from arapaima would provide the first evidence for a link of this family of transcriptional regulators to sex determination. Our study broadens our current understanding about the evolution of sex determination genetic networks and provide a tool for improving arapaima aquaculture for commercial and conservation purposes. |
DOI | 10.1038/s41598-021-01066-z |
Alternate Journal | Sci Rep |
PubMed ID | 34732792 |
PubMed Central ID | PMC8566520 |