Dataset Information

Ecological genomics in the Northern krill uncovers loci for local adaptation across ocean basins.

ABSTRACT: Krill are vital as food for many marine animals but also impacted by global warming. To learn how they and other zooplankton may adapt to a warmer world we studied local adaptation in the widespread Northern krill (Meganyctiphanes norvegica). We assemble and characterize its large genome and compare genome-scale variation among 74 specimens from the colder Atlantic Ocean and warmer Mediterranean Sea. The 19 Gb genome likely evolved through proliferation of retrotransposons, now targeted for inactivation by extensive DNA methylation, and contains many duplicated genes associated with molting and vision. Analysis of 760 million SNPs indicates extensive homogenizing gene-flow among populations. Nevertheless, we detect signatures of adaptive divergence across hundreds of genes, implicated in photoreception, circadian regulation, reproduction and thermal tolerance, indicating polygenic adaptation to light and temperature. The top gene candidate for ecological adaptation was nrf-6, a lipid transporter with a Mediterranean variant that may contribute to early spring reproduction. Such variation could become increasingly important for fitness in Atlantic stocks. Our study underscores the widespread but uneven distribution of adaptive variation, necessitating characterization of genetic variation among natural zooplankton populations to understand their adaptive potential, predict risks and support ocean conservation in the face of climate change.

SUBMITTER: Unneberg P

PROVIDER: S-EPMC11294593 | biostudies-literature | 2024 Aug

REPOSITORIES: biostudies-literature

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Ecological genomics in the Northern krill uncovers loci for local adaptation across ocean basins.

Unneberg Per P Larsson Mårten M Olsson Anna A Wallerman Ola O Petri Anna A Bunikis Ignas I Vinnere Pettersson Olga O Papetti Chiara C Gislason Astthor A Glenner Henrik H Cartes Joan E JE Blanco-Bercial Leocadio L Eriksen Elena E Meyer Bettina B Wallberg Andreas A

Nature communications 20240801 1

Krill are vital as food for many marine animals but also impacted by global warming. To learn how they and other zooplankton may adapt to a warmer world we studied local adaptation in the widespread Northern krill (Meganyctiphanes norvegica). We assemble and characterize its large genome and compare genome-scale variation among 74 specimens from the colder Atlantic Ocean and warmer Mediterranean Sea. The 19 Gb genome likely evolved through proliferation of retrotransposons, now targeted for inac ...[more]

PMID: 39090106

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Dataset Information

Ecological genomics in the Northern krill uncovers loci for local adaptation across ocean basins.

Publications

Ecological genomics in the Northern krill uncovers loci for local adaptation across ocean basins.

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