The RNA-dependent DNA methylation pathway is required to restrict SPOROCYTELESS/NOZZLE expression to specify a single female germ cell precursor in Arabidopsis
Files
(Published Version)
Date
2020
Authors
Mendes, M.A.
Petrella, R.
Cucinotta, M.
Vignati, E.
Gatti, S.
Pinto, S.C.
Bird, D.C.
Gregis, V.
Dickinson, H.
Tucker, M.R.
Editors
Advisors
Journal Title
Journal ISSN
Volume Title
Type:
Journal article
Citation
Development, 2020; 147(23):dev194274.-1-dev194274.-11
Statement of Responsibility
Marta A. Mendes, Rosanna Petrella, Mara Cucinotta, Edoardo Vignati, Stefano Gatti, Sara C. Pinto, Dayton C. Bird, Veronica Gregis, Hugh Dickinson, Matthew R. Tucker and Lucia Colombo
Conference Name
Abstract
In higher plants, the female germline is formed from the megaspore mother cell (MMC), a single cell in the premeiotic ovule. Previously, it was reported that mutants in the RNA-dependent DNA methylation (RdDM) pathway might be involved in restricting the female germline to a single nucellus cell. We show that the DRM methyltransferase double mutant drm1drm2 also presents ectopic enlarged cells, consistent with supernumerary MMC-like cells. In wild-type ovules, MMC differentiation requires SPOROCYTELESS/NOZZLE (SPL/NZZ), as demonstrated by the spl/nzz mutant failing to develop an MMC. We address the poorly understood upstream regulation of SPL/NZZ in ovules, showing that the RdDM pathway is important to restrict SPL/NZZ expression. In ago9, rdr6 and drm1drm2 mutants, SPL/NZZ is expressed ectopically, suggesting that the multiple MMC-like cells observed might be attributable to the ectopic expression of SPL/NZZ. We show that the ovule identity gene, SEEDSTICK, directly regulates AGO9 and RDR6 expression in the ovule and therefore indirectly regulates SPL/NZZ expression. A model is presented describing the network required to restrict SPL/NZZ expression to specify a single MMC.
School/Discipline
Dissertation Note
Provenance
Description
Access Status
Rights
© 2020. Published by The Company of Biologists Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution and reproduction in any medium provided that the original work is properly attributed.