Dataset Information

RADseq provides evidence for parallel ecotypic divergence in the autotetraploid Cochlearia officinalis in Northern Norway.

ABSTRACT: Speciation encompasses a continuum over time from freely interbreeding populations to reproductively isolated species. Along this process, ecotypes - the result of local adaptation - may be on the road to new species. We investigated whether three autotetraploid Cochlearia officinalis ecotypes, adapted to different habitats (beach, estuary, spring), are genetically differentiated and result from parallel ecotypic divergence in two distinct geographical regions. We obtained genetic data from thousands of single nucleotide polymorphisms (SNPs) from restriction-site associated DNA sequencing (RADseq) and from six microsatellite markers for 12 populations to assess genetic divergence at ecotypic, geographic and population level. The genetic patterns support differentiation among ecotypes as suggested by morphology and ecology. The data fit a scenario where the ancestral beach ecotype has recurrently and polytopically given rise to the estuary and spring ecotypes. Several ecologically-relevant loci with consistent non-random segregating patterns are identified across the recurrent origins, in particular around genes related to salt stress. Despite being ecologically distinct, the Cochlearia ecotypes still represent an early stage in the process of speciation, as reproductive isolation has not (yet) developed. A sequenced annotated genome is needed to specifically target candidate genes underlying local adaptation.

SUBMITTER: Brandrud MK

PROVIDER: S-EPMC5514025 | biostudies-literature | 2017 Jul

REPOSITORIES: biostudies-literature

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RADseq provides evidence for parallel ecotypic divergence in the autotetraploid Cochlearia officinalis in Northern Norway.

Brandrud Marie K MK Paun Ovidiu O Lorenzo Maria T MT Nordal Inger I Brysting Anne K AK

Scientific reports 20170717 1

Speciation encompasses a continuum over time from freely interbreeding populations to reproductively isolated species. Along this process, ecotypes - the result of local adaptation - may be on the road to new species. We investigated whether three autotetraploid Cochlearia officinalis ecotypes, adapted to different habitats (beach, estuary, spring), are genetically differentiated and result from parallel ecotypic divergence in two distinct geographical regions. We obtained genetic data from thou ...[more]

PMID: 28717144

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Dataset Information

RADseq provides evidence for parallel ecotypic divergence in the autotetraploid Cochlearia officinalis in Northern Norway.

Publications

RADseq provides evidence for parallel ecotypic divergence in the autotetraploid Cochlearia officinalis in Northern Norway.

Similar Datasets

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