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Summary: Lipids and lipid metabolites have essential roles in plant–pathogen interactions. GDSL‐type lipases are involved in lipid metabolism modulating lipid homeostasis. Some plant GDSLs modulate lipid metabolism altering hormone signal transduction to regulate host‐defence immunity. Here, we functionally characterized a rice lipase, OsGELP77, promoting both immunity and yield. OsGELP77 expression was induced by pathogen infection and jasmonic acid (JA) treatment. Overexpression of OsGELP77 enhanced rice resistance to both bacterial and fungal pathogens, while loss‐of‐function of osgelp77 showed susceptibility. OsGELP77 localizes to endoplasmic reticulum and is a functional lipase hydrolysing universal lipid substrates. Lipidomics analyses demonstrate that OsGELP77 is crucial for lipid metabolism and lipid‐derived JA homeostasis. Genetic analyses confirm that OsGELP77‐modulated resistance depends on JA signal transduction. Moreover, population genetic analyses indicate that OsGELP77 expression level is positively correlated with rice resistance against pathogens. Three haplotypes were classified based on nucleotide polymorphisms in the OsGELP77 promoter where OsGELP77Hap3 is an elite haplotype. Three OsGELP77 haplotypes are differentially distributed in wild and cultivated rice, while OsGELP77Hap3 has been broadly pyramided for hybrid rice development. Furthermore, quantitative trait locus (QTL) mapping and resistance evaluation of the constructed near‐isogenic line validated OsGELP77, a QTL for broad‐spectrum disease resistance. In addition, OsGELP77‐modulated lipid metabolism promotes JA accumulation facilitating grain yield. Notably, the hub defence regulator OsWRKY45 acts upstream of OsGELP77 by initiating the JA‐dependent signalling to trigger immunity. Together, OsGELP77, a QTL contributing to immunity and yield, is a candidate for breeding broad‐spectrum resistant and high‐yielding rice. [ABSTRACT FROM AUTHOR]

Summary: Plants have evolved complex signalling networks to regulate growth and defence responses under an ever‐changing environment. However, the molecular mechanisms underlying the growth‐defence tradeoff are largely unclear. We previously reported that rice CALCIUM‐DEPENDENT PROTEIN KINASE 18 (OsCPK18) and MITOGEN‐ACTIVATED PROTEIN KINASE 5 (OsMPK5) mutually phosphorylate each other and that OsCPK18 phosphorylates and positively regulates OsMPK5 to suppress rice immunity. In this study, we found that OsCPK18 and its paralog OsCPK4 positively regulate plant height and yield‐related traits. Further analysis reveals that OsCPK18 and OsMPK5 synergistically regulate defence‐related genes but differentially regulate development‐related genes. In vitro and in vivo kinase assays demonstrated that OsMPK5 phosphorylates C‐terminal threonine (T505) and serine (S512) residues of OsCPK18 and OsCPK4, respectively. The kinase activity of OsCPK18T505D, in which T505 was replaced by aspartic acid to mimic T505 phosphorylation, displayed less calcium sensitivity than that of wild‐type OsCPK18. Interestingly, editing the MAPK phosphorylation motif in OsCPK18 and its paralog OsCPK4, which deprives OsMPK5‐mediated phosphorylation but retains calcium‐dependent activation of kinase activity, simultaneously increases rice yields and immunity. This editing event also changed the last seven amino acid residues of OsCPK18 and attenuated its binding with OsMPK5. This study presents a new regulatory circuit that fine tunes the growth‐defence tradeoff by modulating OsCPK18/4 activity and suggests that CRISPR/Cas9‐mediated engineering phosphorylation pathways could simultaneously improve crop yield and immunity. [ABSTRACT FROM AUTHOR]

Summary: Over the last three decades, the development of new genome editing techniques, such as ODM, TALENs, ZFNs and the CRISPR‐Cas system, has led to significant progress in the field of plant and animal breeding. The CRISPR‐Cas system is the most versatile genome editing tool discovered in the history of molecular biology because it can be used to alter diverse genomes (e.g. genomes from both plants and animals) including human genomes with unprecedented ease, accuracy and high efficiency. The recent development and scope of CRISPR‐Cas system have raised new regulatory challenges around the world due to moral, ethical, safety and technical concerns associated with its applications in pre‐clinical and clinical research, biomedicine and agriculture. Here, we review the art, applications and potential risks of CRISPR‐Cas system in genome editing. We also highlight the patent and ethical issues of this technology along with regulatory frameworks established by various nations to regulate CRISPR‐Cas‐modified organisms/products. [ABSTRACT FROM AUTHOR]

Summary: Multilocular silique is a desirable agricultural trait with great potential for the development of high‐yield varieties of Brassica. To date, no spontaneous or induced multilocular mutants have been reported in Brassica napus, which likely reflects its allotetraploid nature and the extremely low probability of the simultaneous random mutagenesis of multiple gene copies with functional redundancy. Here, we present evidence for the efficient knockout of rapeseed homologues of CLAVATA3 (CLV3) for a secreted peptide and its related receptors CLV1 and CLV2 in the CLV signalling pathway using the CRISPR/Cas9 system and achieved stable transmission of the mutations across three generations. Each BnCLV gene has two copies located in two subgenomes. The multilocular phenotype can be recovered only in knockout mutations of both copies of each BnCLV gene, illustrating that the simultaneous alteration of multiple gene copies by CRISPR/Cas9 mutagenesis has great potential in generating agronomically important mutations in rapeseed. The mutagenesis efficiency varied widely from 0% to 48.65% in T0 with different single‐guide RNAs (sgRNAs), indicating that the appropriate selection of the sgRNA is important for effectively generating indels in rapeseed. The double mutation of BnCLV3 produced more leaves and multilocular siliques with a significantly higher number of seeds per silique and a higher seed weight than the wild‐type and single mutant plants, potentially contributing to increased seed production. We also assessed the efficiency of the horizontal transfer of Cas9/gRNA cassettes by pollination. Our findings reveal the potential for plant breeding strategies to improve yield traits in currently cultivated rapeseed varieties. [ABSTRACT FROM AUTHOR]