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Phytochrome (Phy)‐regulated light signalling plays important roles in plant growth, development, and stress responses. However, its function in rice defence against sheath blight disease (ShB) remains unclear. Here, we found that PhyB mutation or shade treatment promoted rice resistance to ShB, while resistance was reduced by PhyB overexpression. Further analysis showed that PhyB interacts with phytochrome‐interacting factor‐like 15 (PIL15), brassinazole resistant 1 (BZR1), and vascular plant one‐zinc‐finger 2 (VOZ2). Plants overexpressing PIL15 were more susceptible to ShB in contrast to bzr1‐D‐overexpressing plants compared with the wild‐type, suggesting that PhyB may inhibit BZR1 to negatively regulate rice resistance to ShB. Although BZR1 is known to regulate brassinosteroid (BR) signalling, the observation that BR signalling negatively regulated resistance to ShB indicated an independent role for BZR1 in controlling rice resistance. It was also found that the BZR1 ligand NAC028 positively regulated resistance to ShB. RNA sequencing showed that cinnamyl alcohol dehydrogenase 8B (CAD8B), involved in lignin biosynthesis was upregulated in both bzr1‐D‐ and NAC028‐overexpressing plants compared with the wild‐type. Yeast‐one hybrid, ChIP, and transactivation assays demonstrated that BZR1 and NAC028 activate CAD8B directly. Taken together, the analyses demonstrated that PhyB‐mediated light signalling inhibits the BZR1‐NAC028‐CAD8B pathway to regulate rice resistance to ShB. Summary Statement: Phytochrome B mutation‐mediated shading condition increased rice resistance to sheath blight. In the light, Phytochrome B translocated from cytosol to nucleus where it interacts with and inhibits BZR1 function. BZR1 interacts with NAC028 to directly activate CAD8B to increase lignin contents by which rice resistance to sheath blight. [ABSTRACT FROM AUTHOR]

SUMMARY: Phytochrome B (PhyB), a red‐light receptor, plays important roles in diverse biological processes in plants; however, its function in NH4+ uptake and stress responses of plants is unclear. Here, we observed that mutation in indeterminate domain 10 (IDD10), which encodes a key transcription factor in NH4+ signaling, led to NH4+‐sensitive root growth in light but not in the dark. Genetic combinations of idd10 and phy mutants demonstrated that phyB, but not phyA or phyC, suppressed NH4+‐sensitive root growth of idd10. PhyB mutants and PhyB overexpressors (PhyB OXs) accumulated more and less NH4+, respectively, compared with wild‐type plants. Real time quantitative polymerase chain reaction (RT‐qPCR) revealed that PhyB negatively regulated NH4+‐mediated induction of Ammonium transporter 1;2 (AMT1;2). AMT1 RNAi plants with suppressed AMT1;1, AMT1;2, and AMT1;3 expression exhibited shorter primary roots under NH4+ conditions. This suggested that NH4+ uptake might be positively associated with root growth. Further, PhyB interacted with and inhibited IDD10 and brassinazole‐resistant 1 (BZR1). IDD10 interacted with BZR1 to activate AMT1;2. NH4+ uptake is known to promote resistance of rice (Oryza sativa) to sheath blight (ShB) and saline–alkaline stress. Inoculation of Rhizoctonia solani demonstrated that PhyB and IDD10 negatively regulated and AMT1 and BZR1 positively regulated resistance of rice to ShB. In addition, PhyB negatively regulated and IDD10 and AMT1 positively regulated resistance of rice to saline–alkaline stress. This suggested that PhyB–IDD10–AMT1;2 signaling regulates the saline–alkaline response, whereas the PhyB–BZR1–AMT1;2 pathway modulates ShB resistance. Collectively, these data prove that mutation in the PhyB gene enhances the resistance of rice to ShB and saline–alkaline stress by increasing NH4+ uptake. Significance Statement: PhyB interacts with and inhibits the activity of IDD10 and BZR1 to increase rice (Oryza sativa) resistance to sheath blight and saline–alkaline stress. [ABSTRACT FROM AUTHOR]

Summary: Sheath blight (ShB) significantly threatens rice yield production. However, the underlying mechanism of ShB defence in rice remains largely unknown. Here, we identified a highly ShB‐susceptible mutant Ds‐m which contained a mutation at the ammonium transporter 1;1 (AMT1;1) D358N. AMT1;1 D358N interacts with AMT1;1, AMT1;2 and AMT1;3 to inhibit the ammonium transport activity. The AMT1 RNAi was more susceptible and similar to the AMT1;1 D358N mutant; however, plants with higher NH4+ uptake activity were less susceptible to ShB. Glutamine synthetase 1;1 (GS1;1) mutant gs1;1 and overexpressors (GS1;1 OXs) were more and less susceptible to ShB respectively. Furthermore, AMT1;1 overexpressor (AMT1;1 OX)/gs1;1 and gs1;1 exhibited a similar response to ShB, suggesting that ammonium assimilation rather than accumulation controls the ShB defence. Genetic and physiological assays further demonstrated that plants with higher amino acid or chlorophyll content promoted rice resistance to ShB. Interestingly, the expression of ethylene‐related genes was higher in AMT1;1 OX and lower in RNAi mutants than in wild‐type. Also, ethylene signalling positively regulated rice resistance to ShB and NH4+ uptake, suggesting that ethylene signalling acts downstream of AMT and also NH4+ uptake is under feedback control. Taken together, our data demonstrated that the AMT1 promotes rice resistance to ShB via the regulation of diverse metabolic and signalling pathways. [ABSTRACT FROM AUTHOR]

The article offers information on the role of the vesicle-associated membrane proteins (VAMPs) and the plant growth materials to regulate the Brassinosteroids (BRs) BRI1 plasma membrane targeting to control plant growth in Arabidopsis. It discusses Brassinosteroids as the bioactive steroid molecules that act as plant hormones. It mentions the SYP22, plant growth hormone for overexpressing transgenic plants.

DEP1-Myc + LPA1-GFP or DEP1-Myc + GFP were transfected into tobacco leaves. Mutation of G-protein subunit DEP1 increases planting density and resistance to sheath blight disease in rice (q) LPA1-GFP protein levels in LPA1-GFP and dep1-ko/LPA1-GFP transgenic plants were examined. Keywords: DEP1; tiller angle; sheath blight disease; LPA1; rice EN DEP1 tiller angle sheath blight disease LPA1 rice 418 420 3 03/15/21 20210301 NES 210301 One of the important goals of crop breeding is yield improvement. [Extracted from the article]

Tissue-specific activation of DOF11 promotes rice resistance to sheath blight disease and increases grain weight via activation of SWEET14 (iii) One-thousand-grain weight of WT, sweet14, DOF11-VP16 and sweet14/DOF11-VP16 plants. (u) Western blot analysis was performed to detect DOF11-VP16-Myc levels using anti-Myc antibody in WT, dof11 and dof11/DOF11-VP16-Myc plants (#1, #2). Keywords: SWEET14; yield; sheath blight disease; DOF11; rice EN SWEET14 yield sheath blight disease DOF11 rice 409 411 3 03/15/21 20210301 NES 210301 Sugar will eventually be exported transporter (SWEET) is a family of sugar transporters that plays a critical role during host and pathogen interaction (Bezrutczyk I et al i ., 2018). [Extracted from the article]

Summary: Pathogen–host interaction is a complicated process; pathogens mainly infect host plants to acquire nutrients, especially sugars. Rhizoctonia solani, the causative agent of sheath blight disease, is a major pathogen of rice. However, it is not known how this pathogen obtains sugar from rice plants. In this study, we found that the rice sugar transporter OsSWEET11 is involved in the pathogenesis of sheath blight disease. Quantitative real‐time polymerase chain reaction (qRT‐PCR) and β‐ d‐glucuronidase expression analyses showed that R. solani infection significantly enhanced OsSWEET11 expression in leaves amongst the clade III SWEET members. The analyses of transgenic plants revealed that Ossweet11 mutants were less susceptible, whereas plants overexpressing OsSWEET11 were more susceptible, to sheath blight compared with wild‐type controls, but the yield of OsSWEET11 mutants and overexpressors was reduced. SWEETs become active on oligomerization. Split‐ubiquitin yeast two‐hybrid, bimolecular fluorescence complementation and co‐immunoprecipitation assays showed that mutated OsSWEET11 interacted with normal OsSWEET11. In addition, expression of conserved residue mutated AtSWEET1 inhibited normal AtSWEET1 activity. To analyse whether inhibition of OsSWEET11 function in mesophyll cells is related to defence against this disease, mutated OsSWEET11 was expressed under the control of the Rubisco promoter, which is specific for green tissues. The resistance of transgenic plants to sheath blight disease, but not other disease, was improved, whereas yield production was not obviously affected. Overall, these results suggest that R. solani might acquire sugar from rice leaves by the activation of OsSWEET11 expression. The plants can be protected from infection by manipulation of the expression of OsSWEET11 without affecting the crop yield. [ABSTRACT FROM AUTHOR]

Indeterminate domain ( IDD) genes are a family of plant transcriptional regulators that function in the control of development and metabolism during growth. Here, the function of Oryza sativa indeterminate domain 10 ( OsIDD10) has been explored in rice plants. Compared with wild-type roots, idd10 mutant roots are hypersensitive to exogenous ammonium. This work aims to define the action of IDD10 on gene expression involved in ammonium uptake and nitrogen ( N) metabolism., The ammonium induction of key ammonium uptake and assimilation genes was examined in the roots of idd10 mutants and IDD10 overexpressors. Molecular studies and transcriptome analysis were performed to identify target genes and IDD10 binding cis-elements., IDD10 activates the transcription of AMT1;2 and GDH2 by binding to a cis-element motif present in the promoter region of AMT1;2 and in the fifth intron of GDH2. IDD10 contributes significantly to the induction of several genes involved in N-linked metabolic and cellular responses, including genes encoding glutamine synthetase 2, nitrite reductases and trehalose-6-phosphate synthase. Furthermore, the possibility that IDD10 might influence the N-mediated feedback regulation of target genes was examined., This study demonstrates that IDD10 is involved in regulatory circuits that determine N-mediated gene expression in plant roots. [ABSTRACT FROM AUTHOR]