Journal article icon

Journal article

Lineage-specific rediploidization is a mechanism to explain time-lags between genome duplication and evolutionary diversificiation

Abstract:

Background

The functional divergence of duplicate genes (ohnologues) retained from whole genome duplication (WGD) is thought to promote evolutionary diversification. However, species radiation and phenotypic diversification is often temporally separated from WGD. Salmonid fish, whose ancestor underwent WGD by autotetraploidization ~95 Ma fit such a 'time-lag' model of post-WGD radiation, which occurred alongside a major delay in the rediploidization process. Here we propose a model, 'lineage-specific ohnologue resolution' (LORe), to address the consequences of delayed rediploidization. Under LORe, speciation precedes rediploidization, allowing independent ohnologue divergence in sister lineages sharing an ancestral WGD event.

Results

Using cross-species sequence capture, phylogenomics and genome-wide analyses of ohnologue expression divergence, we demonstrate the major impact of LORe on salmonid evolution. One quarter of each salmonid genome, harbouring at least 4,550 ohnologues, has evolved under LORe, with rediploidization and functional divergence occurring on multiple independent occasions > 50 Myr post-WGD. We demonstrate the existence and regulatory divergence of many LORe ohnologues with functions in lineage-specific physiological adaptations that potentially facilitated salmonid species radiation. We show that LORe ohnologues are enriched for different functions than 'older' ohnologues that began diverging in the salmonid ancestor.

Conclusions

LORe has unappreciated significance as a nested component of post-WGD divergence that impacts the functional properties of genes, whilst providing ohnologues available solely for lineage-specific adaptation. Under LORe, which is predicted following many WGD events, the functional outcomes of WGD need not appear 'explosively', but can arise gradually over tens of Myr, promoting lineage-specific diversification regimes under prevailing ecological pressures.

Publication status:
Published
Peer review status:
Peer reviewed

Actions

Access Document

Publisher copy:
10.1186/s13059-017-1241-z

Authors


Publisher:
BioMed Central
Journal:
Genome Biology More from this journal
Volume:
18
Pages:
111
Publication date:
2017-06-01
Acceptance date:
2017-05-15
DOI:
EISSN:
1465-6906
ISSN:
1474-760X


Keywords:
Pubs id:
pubs:695414
UUID:
uuid:dcc8ccb0-6bd8-405c-99e7-1ad3220ff332
Local pid:
pubs:695414
Source identifiers:
695414
Deposit date:
2017-05-15
ARK identifier:

Terms of use


Views and Downloads






If you are the owner of this record, you can report an update to it here: Report update to this record

TO TOP