Repositorium
Rice Interploidy Crosses Disrupt Epigenetic Regulation, Gene Expression, and Seed Development
bearbeiten
355
Typ / Jahr
Journal Article / 2018
Autoren
Wang, Limei; Yuan, Jingya; Ma, Yujie; Jiao, Wu; Ye, Wenxue; Yang, Dong-Lei; Yi, Chuandeng; Chen, Z. Jeffrey
Abstract
Seed development in angiosperms requires a 2:1 maternal-to-paternal genome ratio (2m:1p) in the endosperm. When the ratio is disrupted, the seed development is impaired. Rice interploidy crosses result in endosperm failures, but the underlying molecular mechanisms remain unclear. Here, we report that the defective endosperm in rice interploidy crosses was associated with nonadditive expression of small RNAs and protein-coding genes. Interestingly, 24-nt small interfering RNAs were enriched in the 50 and 30 flanking sequences of nonadditively expressed genes in the interploidy crosses and were negatively associated with the expression of imprinted genes. Furthermore, some PRC2 family genes and DNA methylation-related genes including OsMET1b and OsCMT3a were upregulated in the 234 cross (pollinating a diploid ‘‘mother’’ with a tetraploid ‘‘father’’) but repressed in the reciprocal cross. These different epigenetic effects could lead to precocious or delayed cellularization during endosperm development. Notably, many endosperm-preferred genes, including starch metabolic and storage protein genes during grain filling, were found to be associated with DNA methylation or H3K27me3, which are repressed in both 234 and 432 crosses. WUSCHEL homeobox2 (WOX2)-like (WOX2L), an endosperm-preferred gene, was expressed specifically in the rice endosperm, in contrast to WOX2 expression in the Arabidopsis embryo. Disruption of WOX2L in transgenic rice by CRISPR/Cas9-mediated gene editing blocked starch and protein accumulation, resulting in seed abortion. In addition to gene repression, disrupting epigenetic process in the interploidy crosses also induced expression of stress-responsive genes. Thus, maintaining the 2m:1p genome ratio in the endosperm is essential for normal grain development in rice and other cereal crops.
Keywords
endosperm; Epigenetics; gene expression; Polyploidy; Seed; Small RNA
Periodical
Molecular plant
Periodical Number
2
Page range
300–314
Volume
11
DOI
10.1016/j.molp.2017.12.006
Techniques
ID | Corresponding Author Country |
Plant Species | GE Technique Sequence Identifier |
Trait Type of Alteration |
Progress in Research Key Topic |
---|---|---|---|---|---|
829 |
Chen, Z. Jeffrey China; USA |
Oryza sativa |
CRISPR/Cas9 WOX2L |
Samenverkümmerung SDN1 |
Basic research Basic research |
830 |
Chen, Z. Jeffrey China; USA |
Oryza sativa |
CRISPR/Cas9 Os03g38210 |
No information SDN1 |
Basic research Basic research |