24-nt reproductive phasiRNAs are broadly present in angiosperms

Nat Commun. 2019 Feb 7;10(1):627. doi: 10.1038/s41467-019-08543-0.


Small RNAs are key regulators in plant growth and development. One subclass, phased siRNAs (phasiRNAs) require a trigger microRNA for their biogenesis. In grasses, two pathways yield abundant phasiRNAs during anther development; miR2275 triggers one class, 24-nt phasiRNAs, coincident with meiosis, while a second class of 21-nt phasiRNAs are present in premeiotic anthers. Here we report that the 24-nt phasiRNA pathway is widely present in flowering plants, indicating that 24-nt reproductive phasiRNAs likely originated with the evolutionary emergence of anthers. Deep comparative genomic analyses demonstrated that this miR2275/24-nt phasiRNA pathway is widely present in eudicots plants, however, it is absent in legumes and in the model plant Arabidopsis, demonstrating a dynamic evolutionary history of this pathway. In Solanaceae species, 24-nt phasiRNAs were observed, but the miR2275 trigger is missing and some loci displaying 12-nt phasing. Both the miR2275-triggered and Solanaceae 24-nt phasiRNAs are enriched in meiotic stages, implicating these phasiRNAs in anther and/or pollen development, a spatiotemporal pattern consistent in all angiosperm lineages that deploy them.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Gene Expression Regulation, Plant
  • Magnoliopsida / genetics*
  • Magnoliopsida / metabolism*
  • Plant Proteins / genetics
  • Plant Proteins / metabolism
  • RNA, Plant / genetics
  • RNA, Plant / metabolism*
  • RNA, Small Interfering / genetics
  • RNA, Small Interfering / metabolism*
  • Solanaceae / genetics
  • Solanaceae / metabolism


  • Plant Proteins
  • RNA, Plant
  • RNA, Small Interfering