The RNA-dependent DNA methylation pathway is required to restrict SPOROCYTELESS/NOZZLE expression to specify a single female germ cell precursor in Arabidopsis

被引：37

作者：

Mendes, Marta A. ^{[1
]}

Petrella, Rosanna ^{[1
]}

Cucinotta, Mara ^{[1
]}

Vignati, Edoardo ^{[1
]}

Gatti, Stefano ^{[1
]}

Pinto, Sara C. ^{[2
]}

Bird, Dayton C. ^{[3
]}

Gregis, Veronica ^{[1
]}

Dickinson, Hugh ^{[4
]}

Tucker, Matthew R. ^{[3
]}

Colombo, Lucia ^{[1
]}

机构：

[1] Univ Milan, Dipartimento Biosci, Via Celoria 26, I-20133 Milan, Italy

[2] Univ Porto, Fac Ciencias, Dept Biol, LAQV REQUIMTE, Rua Campo Alegre S-N, P-4169007 Porto, Portugal

[3] Univ Adelaide, Sch Agr Food & Wine, Waite Campus, Urrbrae, SA 5064, Australia

[4] Univ Oxford, Dept Plant Sci, South Pk Rd, Oxford OX1 3RB, England

来源：

DEVELOPMENT | 2020年 / 147卷 / 23期

基金：

澳大利亚研究理事会; 英国生物技术与生命科学研究理事会;

关键词：

Female germline; MADS-box transcription factors; MMC; RdDM; SPOROCYTELESS; SEEDSTICK; MADS-BOX GENES; OVULE DEVELOPMENT; SEXUAL REPRODUCTION; MOLECULAR-MECHANISM; EPIGENETIC PATHWAY; WILD-TYPE; CYTOKININ; SEEDSTICK; COMPLEX; TARGET;

D O I：

10.1242/dev.194274

中图分类号：

Q [生物科学];

学科分类号：

07 ; 0710 ; 09 ;

摘要：

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 drmldrm2 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 SPU 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 SPU NZZ expression. A model is presented describing the network required to restrict SPL/NZZ expression to specify a single MMC.

引用

页数：11