Landscape of Fluid Sets of Hairpin-Derived 21-/24-nt-Long Small RNAs at Seed Set Uncovers Special Epigenetic Features in Picea glauca.

ABSTRACT: Conifers' exceptionally large genome (20-30 Gb) is scattered with 60% retrotransposon (RT) components and we have little knowledge on their origin and evolutionary implications. RTs may impede the expression of flanking genes and provide sources of the formation of novel small RNA (sRNAs) populations to constrain events of transposon (TE) proliferation/transposition. Here we show a declining expression of 24-nt-long sRNAs and low expression levels of their key processing gene, pgRTL2 (RNASE THREE LIKE 2) at seed set in Picea glauca. The sRNAs in 24-nt size class are significantly less enriched in type and read number than 21-nt sRNAs and have not been documented in other species. The architecture of MIR loci generating highly expressed 24-/21-nt sRNAs is featured by long terminal repeat-re

SUBMITTER: Liu Y 

PROVIDER: S-EPMC5381586 | biostudies-literature | 2017 Jan

REPOSITORIES: biostudies-literature