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Molecular dissection of a natural transposable element invasion.

ABSTRACT: The first tracking of the dynamics of a natural invasion by a transposable element (TE) provides unprecedented details on the establishment of host defense mechanisms against TEs. We captured a D. simulans population at an early stage of a P-element invasion and studied the spread of the TE in replicated experimentally evolving populations kept under hot and cold conditions. We analyzed the factors controlling the invasion by NGS, RNA-FISH, and gonadal dysgenesis assays. Under hot conditions, the P-element spread rapidly for 20 generations, but no further spread was noted later on. This plateauing of the invasion was mediated by the rapid emergence of P-element-specific piRNAs. Under cold conditions, we observed a lower expression of the P-element and a slower emergence of the piRNA defense, resulting in a three times slower invasion that continued beyond 40 generations. We conclude that the environment is a major factor determining the evolution of TEs in their host.

SUBMITTER: Kofler R

PROVIDER: S-EPMC5991514 | biostudies-literature | 2018 Jun

REPOSITORIES: biostudies-literature

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Molecular dissection of a natural transposable element invasion.

Kofler Robert R Senti Kirsten-André KA Nolte Viola V Tobler Ray R Schlötterer Christian C

Genome research 20180430 6

The first tracking of the dynamics of a natural invasion by a transposable element (TE) provides unprecedented details on the establishment of host defense mechanisms against TEs. We captured a D. simulans population at an early stage of a P-element invasion and studied the spread of the TE in replicated experimentally evolving populations kept under hot and cold conditions. We analyzed the factors controlling the invasion by NGS, RNA-FISH, and gonadal dysgenesis assays. Und ...[more]

PMID: 29712752

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