RT Journal Article SR Electronic T1 Small RNAs reflect grandparental environments in apomictic dandelion JF bioRxiv FD Cold Spring Harbor Laboratory SP 099572 DO 10.1101/099572 A1 Lionel Morgado A1 Veronica Preite A1 Carla Oplaat A1 Sarit Anava A1 Julie Ferreira de Carvalho A1 Oded Rechavi A1 Frank Johannes A1 Koen J.F. Verhoeven YR 2017 UL http://biorxiv.org/content/early/2017/01/11/099572.abstract AB Plants can show long-term effects of environmental stresses and in some cases a stress ‘memory’ has been reported to persist across generations, potentially mediated by epigenetic mechanisms. However, few documented cases exist of transgenerational effects that persist for multiple generations and it remains unclear if or how epigenetic mechanisms are involved. Here we show that the composition of small regulatory RNAs in apomictic dandelion lineages reveals a footprint of drought stress and salicylic acid treatment experienced two generations ago. Overall proportions of 21nt and 24nt RNA pools were shifted due to grandparental treatments. While individual genes did not show strong up- or downregulation of associated sRNAs, the subset of genes that showed the strongest shifts in sRNA abundance was significantly enriched for several GO terms including stress-specific functions. This indicates that a stress-induced signal was transmitted across multiple unexposed generations leading to persistent and functional changes in epigenetic gene regulation.