MiR2118-triggered phased siRNAs are differentially expressed during the panicle development of wild and domesticated African rice species Ta K. N. auteur aut IRD Sabot François auteur aut IRD Adam Hélène auteur aut IRD Vigouroux Yves auteur aut IRD De Mita Stéphane auteur aut IRD Ghesquière Alain auteur aut IRD Do N. V. auteur aut IRD Gantet Pascal auteur aut IRD Jouannic Stefan auteur aut IRD text journalArticle eng text/pdf reformatted digital access Background: Rice exhibits a wide range of panicle structures. To explain these variations, much emphasis has been placed on changes in transcriptional regulation, but no large-scale study has yet reported on changes in small RNA regulation in the various rice species. To evaluate this aspect, we performed deep sequencing and expression profiling of small RNAs from two closely related species with contrasting panicle development: the cultivated African rice Oryza glaberrima and its wild relative Oryza barthii. Results: Our RNA-seq analysis revealed a dramatic difference between the two species in the 21 nucleotide small RNA population, corresponding mainly to miR2118-triggered phased siRNAs. A detailed expression profiling during the panicle development of O. glaberrima and O. barthii using qRT-PCRs and in situ hybridization, confirmed a delayed expression of the phased siRNAs as well as their lncRNA precursors and regulators (miR2118 and MEL1 gene) in O. glaberrima compared to O. barthii. We provide evidence that the 21-nt phasiRNA pathway in rice is associated with male-gametogenesis but is initiated in spikelet meristems. Conclusion: Differential expression of the miR2118-triggered 21-nt phasiRNA pathway between the two African rice species reflects differential rates of determinate fate acquisition of panicle meristems between the two species. specialized Panicle Meristem Small RNAs phasiRNAs miR2118 Domestication Oryza barthii Oryza glaberrima AFRIQUE 076 Rice 9 art. 10 [14 ] 2016 1939-8425 https://www.documentation.ird.fr/hor/fdi:010068865 10.1186/s12284-016-0082-9 1939-8425 [F B010068865] https://www.documentation.ird.fr/hor/fdi:010068865 https://horizon.documentation.ird.fr/exl-doc/pleins_textes/divers17-02/010068865.pdf IRD - Base Horizon / Pleins textes 2017-03-02 2020-06-02 fdi:010068865 fre