Enhanced sustainable green revolution yield via nitrogen-responsive chromatin modulation in rice

Abstract

Because environmentally degrading inorganic fertilizer use underlies current worldwide cereal yields, future agricultural sustainability demands enhanced nitrogen use efficiency. We found that genome-wide promotion of histone H3 lysine 27 trimethylation (H3K27me3) enables nitrogen-induced stimulation of rice tillering: APETALA2-domain transcription factor NGR5 (NITROGEN-MEDIATED TILLER GROWTH RESPONSE 5) facilitates nitrogen-dependent recruitment of polycomb repressive complex 2 to repress branching-inhibitory genes via H3K27me3 modification. NGR5 is a target of gibberellin receptor GIBBERELLIN INSENSITIVE DWARF1 (GID1)–promoted proteasomal destruction. DELLA proteins (characterized by the presence of a conserved aspartate-glutamate-leucine-leucine-alanine motif) competitively inhibit the GID1-NGR5 interaction and explain increased tillering of green revolution varieties. Increased NGR5 activity consequently uncouples tillering from nitrogen regulation, boosting rice yield at low nitrogen fertilization levels. NGR5 thus enables enhanced nitrogen use efficiency for improved future agricultural sustainability and food security.

Comparative Transcriptomics of Rice Genotypes with Contrasting Responses to Nitrogen Stress Reveals Genes Influencing Nitrogen Uptake through the Regulation of Root Architecture

“…This observation suggests the superiority of the Pokkali allele in enhancing N uptake under N stress. A recent study discovered the role of GID1 and nitrogen-mediated tiller growth response 5 (NGR5 (LOC_Os5g32270)) in gibberellin signaling by nitrogen fertilization to enhance tillering in rice [49]. NGR5, an APETALA2-domain transcription factor responsible for recruiting polycomb repressive complex 2 (PRC2) to regulate the transcription of tillering repressing genes, is dependent on nitrogen application.…”

How does nitrogen shape plant architecture?

“…In general, the effect of the level of N supply on plant height can be predicted, whereas its effect on other architecture components, such as tiller number, filled grains per panicle, 1000-grain weight, and grain yield, is complicated. Sufficient N supply stimulates shoot elongation and ensures that the plant will reach the expected height in both rice and wheat ( Wu et al , 2020 ), while excess N prevents secondary cell wall formation, resulting in poor lodging resistance ( Wu et al , 2017 ; Zhang et al , 2017 ). The tiller number is affected by the N supply level and growth stage.…”

Integrative Metabolomic and Transcriptomic Analyses Reveal Metabolic Changes and Its Molecular Basis in Rice Mutants of the Strigolactone Pathway

“…Our work also provides new insights into the crosstalk of SLs with GAs, mutants of which in various cereals led to the green revolution [67]. GAs and SLs have been shown to regulate a largely overlapping set of genes in Arabidopsis [68].…”

“…Most of the biosynthetic genes of SLs are repressed by GAs [69]. Most recently, D14 has been proven to be positively controlled by GAs via histone H3 lysine 27 trimethylation [67]. By and large, these studies clarified that GAs work upstream of SLs by regulating the biosynthesis and signal transduction of the latter.…”