24-nt reproductive phasiRNAs are broadly present in angiosperms

• Published in: Nature communications Vol. 10; no. 1; p. 627
• Main Authors: Xia, Rui, Chen, Chengjie, Pokhrel, Suresh, Ma, Wuqiang, Huang, Kun, Patel, Parth, Wang, Fuxi, Xu, Jing, Liu, Zhongchi, Li, Jianguo, Meyers, Blake C.
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 07.02.2019; Nature Publishing Group; Nature Portfolio
• Subjects: 14; 14/32; 38; 38/91; 45; 631/337/384/2054; 631/449/2679/1743; Angiosperms; Anthers; Biological evolution; Biology; Flowering; Flowers & plants; Gene Expression Regulation, Plant; Genomes; Genomic analysis; Grasses; Humanities and Social Sciences; Laboratories; Legumes; Magnoliopsida - genetics; Magnoliopsida - metabolism; Meiosis; MicroRNAs; miRNA; multidisciplinary; Plant growth; Plant Proteins - genetics; Plant Proteins - metabolism; Plant reproductive structures; Plants (botany); Pollen; Regulators; Ribonucleic acid; RNA; RNA, Plant - genetics; RNA, Plant - metabolism; RNA, Small Interfering - genetics; RNA, Small Interfering - metabolism; Science; Science (multidisciplinary); siRNA; Soil sciences; Solanaceae; Solanaceae - genetics; Solanaceae - metabolism
• ISSN: 2041-1723; 2041-1723
• 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. 24-nt phased siRNA (phasiRNA) regulate reproduction in grasses, yet are absent from Arabidopsis , and were thought to be monocot-specific. Here, Xia et al. show that 24-nt phasiRNAs are in fact broadly distributed among eudicots and are consistently enriched during meiosis, despite possibly arising from distinct biogenesis pathways.