Dataset Information

De-novo emergence of SINE retroposons during the early evolution of passerine birds.

ABSTRACT:

Background

Passeriformes ("perching birds" or passerines) make up more than half of all extant bird species. The genome of the zebra finch, a passerine model organism for vocal learning, was noted previously to contain thousands of short interspersed elements (SINEs), a group of retroposons that is abundant in mammalian genomes but considered largely inactive in avian genomes.

Results

Here we resolve the deep phylogenetic relationships of passerines using presence/absence patterns of SINEs. The resultant retroposon-based phylogeny provides a powerful and independent corroboration of previous sequence-based analyses. Notably, SINE activity began in the common ancestor of Eupasseres (passerines excluding the New Zealand wrens Acanthisittidae) and ceased before the rapid diversification of oscine passerines (suborder Passeri - songbirds). Furthermore, we find evidence for very recent SINE activity within suboscine passerines (suborder Tyranni), following the emergence of a SINE via acquisition of a different tRNA head as we suggest through template switching.

Conclusions

We propose that the early evolution of passerines was unusual among birds in that it was accompanied by de-novo emergence and activity of SINEs. Their genomic and transcriptomic impact warrants further study in the light of the massive diversification of passerines.

SUBMITTER: Suh A

PROVIDER: S-EPMC5729268 | biostudies-literature | 2017

REPOSITORIES: biostudies-literature

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Publications

<i>De-novo</i> emergence of SINE retroposons during the early evolution of passerine birds.

Suh Alexander A Bachg Sandra S Donnellan Stephen S Joseph Leo L Brosius Jürgen J Kriegs Jan Ole JO Schmitz Jürgen J

Mobile DNA 20171214

<h4>Background</h4>Passeriformes ("perching birds" or passerines) make up more than half of all extant bird species. The genome of the zebra finch, a passerine model organism for vocal learning, was noted previously to contain thousands of short interspersed elements (SINEs), a group of retroposons that is abundant in mammalian genomes but considered largely inactive in avian genomes.<h4>Results</h4>Here we resolve the deep phylogenetic relationships of passerines using presence/absence patterns ...[more]

PMID: 29255493

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