The RNA-dependent DNA methylation pathway is required to restrict SPOROCYTELESS/NOZZLE expression to specify a single female germ cell precursor in Arabidopsis.
Development
; 147(23)2020 12 13.
Article
en En
| MEDLINE
| ID: mdl-33158925
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.
Palabras clave
Texto completo:
1
Bases de datos:
MEDLINE
Asunto principal:
Proteínas Represoras
/
Proteínas Nucleares
/
Arabidopsis
/
Metilación de ADN
/
Proteínas de Dominio MADS
/
Proteínas de Arabidopsis
Tipo de estudio:
Prognostic_studies
Idioma:
En
Revista:
Development
Asunto de la revista:
BIOLOGIA
/
EMBRIOLOGIA
Año:
2020
Tipo del documento:
Article
País de afiliación:
Italia