In:
New Phytologist, Wiley, Vol. 212, No. 4 ( 2016-12), p. 1094-1105
Kurzfassung:
Argonaute (Ago) proteins are important effectors in RNA silencing pathways, but they must interact with other machinery to trigger silencing. Ago hooks have emerged as a conserved motif responsible for interaction with Ago proteins, but little is known about the sequence surrounding Ago hooks that must restrict or enable interaction with specific Argonautes. Here we investigated the evolutionary dynamics of an Ago‐binding platform in NRPE 1, the largest subunit of RNA polymerase V. We compared NRPE 1 sequences from 〉 50 species, including dense sampling of two plant lineages. This study demonstrates that the Ago‐binding platform of NRPE 1 retains Ago hooks, intrinsic disorder, and repetitive character while being highly labile at the sequence level. We reveal that loss of sequence conservation is the result of relaxed selection and frequent expansions and contractions of tandem repeat arrays. These factors allow a complete restructuring of the Ago‐binding platform over 50–60 million yr. This evolutionary pattern is also detected in a second Ago‐binding platform, suggesting it is a general mechanism. The presence of labile repeat arrays in all analyzed NRPE 1 Ago‐binding platforms indicates that selection maintains repetitive character, potentially to retain the ability to rapidly restructure the Ago‐binding platform.
Materialart:
Online-Ressource
ISSN:
0028-646X
,
1469-8137
DOI:
10.1111/nph.2016.212.issue-4
Sprache:
Englisch
Verlag:
Wiley
Publikationsdatum:
2016
ZDB Id:
208885-X
ZDB Id:
1472194-6
