Soil salinization and blast disease are major constraints on global rice production.Although plants modulate oxidative homeostasis to withstand such stresses,the genetic components that coordinate abiotic and biotic s...Soil salinization and blast disease are major constraints on global rice production.Although plants modulate oxidative homeostasis to withstand such stresses,the genetic components that coordinate abiotic and biotic stress responses through reactive oxygen species scavenging remain poorly defined.Here,we identify STBR1,a BAHD acyltransferase-encoding gene,as a key regulator that confers both saline-alkali stress tolerance and blast resistance.Through association analysis and transgenic validation,we show that STBR1 overexpression enhances stress tolerance and increases grain yield.Mechanistically,yeast twohybrid,co-immunoprecipitation,and biochemical analyses reveal that STBR1 physically interacts with and stabilizes the non-canonical catalase CATA,thereby promoting H 2 O 2 scavenging and mitigating oxidative damage.We further identified a natural elite haplotype,STBR1-T,which harbors a promoter mutation that weakens binding by the transcriptional repressor NAC2-as confirmed by electrophoretic mobility shift assay and chromatin immunoprecipitation-qPCR-resulting in elevated STBR1 expression and enhanced stress resilience in rice.Together,our findings define the NAC2-STBR1-CATA regulatory module as a central hub that coordinates oxidative homeostasis under combined abiotic and biotic stresses.The STBR1-T allele represents a valuable genetic resource for breeding high-yielding rice cultivars with robust,broad-spectrum stress resistance.展开更多
Pentatricopeptide repeat(PPR) proteins, composing one of the largest protein families in plants,are involved in RNA binding and regulation of organelle RNA metabolism at the posttranscriptional level. Although several...Pentatricopeptide repeat(PPR) proteins, composing one of the largest protein families in plants,are involved in RNA binding and regulation of organelle RNA metabolism at the posttranscriptional level. Although several PPR proteins have been implicated in endosperm development in rice(Oryza sativa), the molecular functions of many PPRs remain obscure. Here, we identified a rice endosperm mutant named floury endosperm 18(flo18) with pleiotropic defects in both reproductive and vegetative development.Map-based cloning and complementation tests showed that FLO18 encodes a mitochondriontargeted P-type PPR protein with 15 PPR motifs.Mitochondrial function was disrupted in the flo18 mutant, as evidenced by decreased assembly of Complex I in the mitochondrial electron transport chain and altered mitochondrial morphology. Loss of FLO18 function resulted in defective 5′-end processing of mitochondrial nad5 transcripts encoding subunit 5 of nicotinamide adenine dinucleotide hydrogenase. These results suggested that FLO18 is involved in 5′-end processing of nad5 messenger RNA and plays an important role in mitochondrial function and endosperm development.展开更多
基金supported by the Foundation of Biological Breeding Zhongshan Lab(ZSBBL-KY2024-01)Scientific Innovation 2030 Project(2022ZD0401703)+4 种基金the National Key Research and Development Project(2022YFD1201702)the National Natural Science Foundation of China(32401844)the Natural Science Foundation of Jiangsu Province(BK20220997,BK20230982,and BK20221276)the Jiangsu Funding Program for Excellent and Postdoctoral Talent(2022ZB351 and 2023ZB492)the China Postdoctoral Science Foundation(2023M741753).The funding agencies had no role in study design,data collection and analysis,the decision to publish,or manuscript preparation.
文摘Soil salinization and blast disease are major constraints on global rice production.Although plants modulate oxidative homeostasis to withstand such stresses,the genetic components that coordinate abiotic and biotic stress responses through reactive oxygen species scavenging remain poorly defined.Here,we identify STBR1,a BAHD acyltransferase-encoding gene,as a key regulator that confers both saline-alkali stress tolerance and blast resistance.Through association analysis and transgenic validation,we show that STBR1 overexpression enhances stress tolerance and increases grain yield.Mechanistically,yeast twohybrid,co-immunoprecipitation,and biochemical analyses reveal that STBR1 physically interacts with and stabilizes the non-canonical catalase CATA,thereby promoting H 2 O 2 scavenging and mitigating oxidative damage.We further identified a natural elite haplotype,STBR1-T,which harbors a promoter mutation that weakens binding by the transcriptional repressor NAC2-as confirmed by electrophoretic mobility shift assay and chromatin immunoprecipitation-qPCR-resulting in elevated STBR1 expression and enhanced stress resilience in rice.Together,our findings define the NAC2-STBR1-CATA regulatory module as a central hub that coordinates oxidative homeostasis under combined abiotic and biotic stresses.The STBR1-T allele represents a valuable genetic resource for breeding high-yielding rice cultivars with robust,broad-spectrum stress resistance.
基金This research was supported by grants from the National Transgenic Science and Technology Program(2019ZX08010-003)the Agricultural Science and Technology Innovation Program of CAAS(CAAS-ZDXT2018001)+1 种基金the Fundamental Research Funds for the Central Universities(KYTZ201601)the Postgraduate Research&Practice Innovation Program of Jiangsu Province(KYCX18_0657)。
文摘Pentatricopeptide repeat(PPR) proteins, composing one of the largest protein families in plants,are involved in RNA binding and regulation of organelle RNA metabolism at the posttranscriptional level. Although several PPR proteins have been implicated in endosperm development in rice(Oryza sativa), the molecular functions of many PPRs remain obscure. Here, we identified a rice endosperm mutant named floury endosperm 18(flo18) with pleiotropic defects in both reproductive and vegetative development.Map-based cloning and complementation tests showed that FLO18 encodes a mitochondriontargeted P-type PPR protein with 15 PPR motifs.Mitochondrial function was disrupted in the flo18 mutant, as evidenced by decreased assembly of Complex I in the mitochondrial electron transport chain and altered mitochondrial morphology. Loss of FLO18 function resulted in defective 5′-end processing of mitochondrial nad5 transcripts encoding subunit 5 of nicotinamide adenine dinucleotide hydrogenase. These results suggested that FLO18 is involved in 5′-end processing of nad5 messenger RNA and plays an important role in mitochondrial function and endosperm development.
