Project description:<p>Pigmented rice (<em>Oryza sativa L.</em>) is a rich source of nutrients, but pigmented lines typically have long life cycles and limited productivity. Here we generated genome assemblies of 5 pigmented rice varieties and evaluated the genetic variation among 51 pigmented rice varieties by resequencing an additional 46 varieties. Phylogenetic analyses divided the pigmented varieties into four varietal groups: Geng-japonica, Xian-indica, circum-Aus and circum-Basmati. Metabolomics and ionomics profiling revealed that black rice varieties are rich in aromatic secondary metabolites. We established a regeneration and transformation system and used CRISPR-Cas9 to knock out three flowering time repressors (Hd2, Hd4 and Hd5) in the black Indonesian rice Cempo Ireng, resulting in an early maturing variety with shorter stature. Our study thus provides a multi-omics resource for understanding and improving Asian pigmented rice.</p>
Project description:The rice blast disease, caused by Magnaporthe oryzae , devastates cultivated rice (Oryza sativa L.), resulting in extensive global crop loss. We employed a label-free quantitative proteomics approach to discover novel proteins associated with M. oryzae pathogenicity and rice defense. We identified 990 significantly modulated proteins in rice leaves including various pattern recognition receptors (PRRs) and pathogenesis-related (PR) proteins that were induced in response to M. oryzae inoculation. Additionally, 123 M. oryzae proteins were also identified and screened for their cell death-inducing activity by an in-silico approach. Among these, we found a novel protein MoXYL1 (endo-1,4-beta-xylanase) protein, which induces cell death in Nicotiana benthamiana leaves. Transgenic rice plants (PDUF26::MoXYL1) expressing MoXYL1 derived by rice domain of unknown function protein 26 (DUF26) promoter exhibited resistance against the M. oryzae and Cochliobolus miyabeanus and enhanced expression of pathogen-responsive genes and hormone-related genes. Furthermore, the application of data-independent acquisition (DIA) mass spectrometry (MS)-based proteomics on these transgenic rice plants revealed 1,833 significantly modulated proteins in response to M. oryzae, with 219 and 410 proteins responsive to MoXYL1 and M. oryzae, respectively. Based on these results, we propose a signaling network model induced by MoXYL1 and M. oryzae. In summary, our findings highlight the crucial role of MoXYL1 in rice innate immunity against M. oryzae and its potential to enhance rice disease resistance.