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1.
Rice (N Y) ; 17(1): 66, 2024 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-39443408

RESUMO

The yield potential of large-panicle rice is often limited by grain-filling barriers caused by the development of inferior spikelets (IS). Photoassimilates, which are the main source of rice grain filling, mainly enter the caryopsis through the dorsal vascular bundle. The distribution of assimilates between superior spikelets (SS) and IS is influenced by auxin-mediated apical dominance; however, the mechanism involved is still unclear. In this study, the effect of auxin signaling on the grain filling of SS and IS was investigated in two large-panicle japonica rice varieties, W1844 and CJ03. Compared to SS, IS displayed delayed initiation of filling and a significantly lower grain weight. Furthermore, the endosperm development in IS remained stagnant at the coenocytic stage. The development of the dorsal vascular bundle in the IS was also slow, and poor sucrose-unloading was observed during the initial grain filling stage. However, the endosperm development in IS immediately started after the improvement of dorsal vascular bundle development. GUS activity staining further revealed that indole-3-acetic (IAA) was localized in the dorsal vascular bundle and surrounding areas, suggesting that the low IAA content observed in the IS during the initial grain filling stage may have delayed the development of the dorsal vascular bundle. Therefore, these results demonstrate that IAA may control sugar transport and unloading by regulating dorsal vascular bundle development, consequently affecting endosperm development in IS.

2.
iScience ; 27(10): 110862, 2024 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-39319271

RESUMO

Rhabdomyosarcoma (RMS) is the most common soft tissue sarcoma in childhood and adolescence. The availability of appropriate and well-characterized preclinical models for RMS is limited, posing a challenge for investigating the molecular mechanisms and evaluating new targeted compounds in preclinical settings. Here, we collected 51 RMS specimens (referred to as ZJUCH-RMS cohort) and established 9 patient-derived cells (PDCs) and validated the identity of these cells by the expression of RMS-specific markers. Whole-transcriptome analysis identified high-confidence mutations in ZJUCH-RMS cohort including RAS, TP53, ARID1A, MYOD1, and MYCN. Further studies showed that RMS PDCs retained the genetic alterations and the expression of RMS hallmark and dependency genes in matched primary tumors and acted as valuable tools to assess drug responses and pharmacogenomic interactions. Our study provides unique PDCs that are available for preclinical studies of RMS and further advances the feasibility of RMS PDCs as valuable tools for developing personalized treatments for patients.

3.
Nat Commun ; 15(1): 8108, 2024 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-39284820

RESUMO

Conventionally, rocking-chair batteries capacity primarily depends on cation shuttling. However, intrinsically high-charge-density metal-ions, such as Al3+, inevitably cause strong Coulombic ion-lattice interactions, resulting in low practical energy density and inferior long-term stability towards rechargeable aluminium batteries (RABs). Herein, we introduce tunable quantum confinement effects and tailor a family of anion/cation co-(de)intercalation superlattice cathodes, achieving high-voltage anion charge compensation, with extra-capacity, in RABs. The optimized superlattice cathode with adjustable van der Waals not only enables facile traditional cation (de)intercalation, but also activates O2- compensation with an extra anion reaction. Furthermore, the constructed cathode delivers high energy-density (466 Wh kg-1 at 107 W kg-1) and one of the best cycle stability (225 mAh g-1 over 3000 cycles at 2.0 A g-1) in RABs. Overall, the anion-involving redox mechanism overcomes the bottlenecks of conventional electrodes, thereby heralding a promising advance in energy-storage-systems.

4.
Chemosphere ; 364: 143084, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39142394

RESUMO

BACKGROUND: There are a few reports on the associations between fine particulate matter (PM2.5)-bound heavy metals and lung function. OBJECTIVES: To evaluate the associations of single and mixed PM2.5-bound heavy metals with lung function. METHODS: This study included 316 observations of 224 Chinese adults from the Wuhan-Zhuhai cohort over two study periods, and measured participants' personal PM2.5-bound heavy metals and lung function. Three linear mixed models, including the single constituent model, the PM2.5-adjusted constituent model, and the constituent residual model were used to evaluate the association between single metal and lung function. Mixed exposure models including Bayesian kernel machine regression (BKMR) model, weighted quantile sum (WQS) model, and Explainable Machine Learning model were used to assess the relationship between PM2.5-bound heavy metal mixtures and lung function. RESULTS: In the single exposure analyses, significant negative associations of PM2.5-bound lead, antimony, and cadmium with peak expiratory flow (PEF) were observed. In the mixed exposure analyses, significant decreases in forced expiratory volume in 1 s (FEV1)/forced vital capacity (FVC), maximal mid-expiratory flow (MMF), and forced expiratory flow at 75% of the pulmonary volume (FEF75) were associated with the increased PM2.5-bound heavy metal mixture. The BKMR models suggested negative associations of PM2.5-bound lead and antimony with lung function. In addition, PM2.5-bound copper was positively associated with FEV1/FVC, MMF, and FEF75. The Explainable Machine Learning models suggested that FEV1/FVC, MMF, and FEF75 decreased with the elevated PM2.5-bound lead, manganese, and vanadium, and increased with the elevated PM2.5-bound copper. CONCLUSIONS: The negative relationships were detected between PM2.5-bound heavy metal mixture and FEV1/FVC, MMF, as well as FEF75. Among the PM2.5-bound heavy metal mixture, PM2.5-bound lead, antimony, manganese, and vanadium were negatively associated with FEV1/FVC, MMF, and FEF75, while PM2.5-bound copper was positively associated with FEV1/FVC, MMF, and FEF75.


Assuntos
Poluentes Atmosféricos , Pulmão , Metais Pesados , Material Particulado , Humanos , Material Particulado/análise , Metais Pesados/análise , Masculino , Feminino , Pessoa de Meia-Idade , Adulto , Poluentes Atmosféricos/análise , China , Pulmão/efeitos dos fármacos , Exposição Ambiental/estatística & dados numéricos , Testes de Função Respiratória , Volume Expiratório Forçado , Teorema de Bayes , Capacidade Vital , Estudos de Coortes , Poluição do Ar/estatística & dados numéricos , Idoso , População do Leste Asiático
5.
Physiol Plant ; 176(4): e14469, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39129660

RESUMO

Poor grain filling in inferior spikelets (IS), which is influenced by the remobilization of nonstructural carbohydrates (NSC) stored in the sheath and internode of rice plants, limits the expected high yield of large-panicle rice. NSC remobilization from the sheath to the panicle is regulated by the T6P/SnRK1 pathway. However, in large-panicle rice, it is unclear whether IS grain filling is related to the NSC remobilization mediated by T6P/SnRK1 signaling. In this study, two large-panicle cultivars-W1844 and CJ03-with distinct differences in IS grain filling were used to explore the physiological mechanism mediating IS development. Compared to W1844, CJ03 IS showed lower expression of the genes related to sucrose uploading, later sucrose peaking, and delayed starch accumulation. In the CJ03, low OsSUTs expression and NSC output, transport rate, and contribution rate were detected in the sheaths and internodes. These results suggest that poor NSC remobilization results in insufficient assimilate supply for the IS, and consequently, poor IS grain filling. Furthermore, poor NSC remobilization coincided with the increased T6P content and decreased SnRK1 activity during grain filling in CJ03 IS. The expression levels of genes related to T6P metabolism and those encoding the catalytic subunit of SnRK1 were consistent with the observed T6P content and SnRK1 activity in the sheaths and internodes. Therefore, IS grain filling is potentially affected by T6P/SnRK1 signaling-mediated NSC remobilization in large-panicle rice.


Assuntos
Regulação da Expressão Gênica de Plantas , Oryza , Proteínas de Plantas , Oryza/genética , Oryza/metabolismo , Oryza/crescimento & desenvolvimento , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Amido/metabolismo , Sacarose/metabolismo , Metabolismo dos Carboidratos/genética , Grão Comestível/genética , Grão Comestível/metabolismo , Grão Comestível/crescimento & desenvolvimento , Sementes/genética , Sementes/metabolismo , Sementes/crescimento & desenvolvimento
6.
J Acoust Soc Am ; 156(2): 1413-1424, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39213459

RESUMO

Active road noise control (ARNC) systems have been widely investigated for low-frequency road noise attenuation in vehicle cabins. Multiple reference and error sensors are usually required to ensure noticeable noise reduction. However, this tends to slow down the convergence speed of adaptive algorithms due to the coupling of secondary paths and the cross correlation of reference signals. Furthermore, the high computational burden of normally utilized multichannel control algorithms exacerbates the difficulty of practical implementations. In this paper, an online decoupling-whitening frequency domain filtered-error least mean square (ODW-FDFeLMS) algorithm is proposed to address the aforementioned problems. Secondary path decoupling through inner-outer product decomposition and online reference whitening through spectral factorization effectively accelerate the convergence rate. Additionally, the utilization of the filtered-error algorithm based on frequency domain processing mitigates the computational complexity. Simulations with measured road noise data confirm the superiority of the ODW-FDFeLMS algorithm over existing algorithms in terms of convergence speed and computational complexity. Real-time experiments in a vehicle cabin further confirm the effectiveness of the proposed algorithm.

8.
World J Clin Cases ; 12(19): 3950-3955, 2024 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-38994291

RESUMO

BACKGROUND: We report a case of eye-penetrating injury in which a massive silicone oil migration into the patient's subconjunctival space and orbit occurred after vitrectomy. CASE SUMMARY: A 30-year-old male patient sought medical attention at Ganzhou People's Hospital after experiencing pain and vision loss in his left eye due to a nail wound on December 9, 2023. Diagnosis of penetrating injury caused by magnetic foreign body retention in the left eye and hospitalization for treatment. On December 9, 2023, pars plana vitrectomy was performed on the left eye for intraocular foreign body removal, abnormal crystal extraction, retinal photocoagulation. Owing to the discovery of retinal detachment at the posterior pole during surgery, silicone oil was injected to fill the vitreous body, following which upper conjunctival bubble-like swelling was observed. Postoperative orbital computed tomography (CT) review indicated migration of silicone oil to the subconjunctival space and orbit through a self-permeable outlet. On December 18, 2023, the patient sought treatment at the First Affiliated Hospital of Nanchang University, China. The patient presented with a pronounced foreign body sensation following left eye surgery. On December 20, 2023, the foreign body was removed from the left eye frame and an intraocular examination was conducted. The posterior scleral tear had closed, leading to termination of the surgical procedure following supplementary laser treatment around the tear. The patient reported a significant reduction in ocular surface symptoms just one day after surgery. Furthermore, a notable decrease in the migration of silicone oil was observed in orbital CT scans. CONCLUSION: The timing of silicone oil injection for an eye-penetrating injury should be carefully evaluated to avoid the possibility of silicone oil migration.

11.
J Acoust Soc Am ; 155(6): 3678-3689, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38847592

RESUMO

Numerous advanced and lightweight signal processing methods have been presented for single-channel speech enhancement (SE). It is imperative to carefully explore how to efficiently combine, integrate, and balance these methods. This paper proposes a more effective and less resource-intensive SE system, focused on the integration and adaptation of several approaches, especially the temporal cepstrum smoothing (TCS). First, a more robust fundamental frequency estimator is employed within TCS, mitigating the performance limitations caused by the inaccuracy of the original estimator. Additionally, a harmonic enhancement mechanism is introduced, effectively recovering the weak harmonic components. By incorporation of the modified TCS in the a posteriori speech presence probability estimation, the unbiased minimum mean square error noise power spectral density estimator can be refined. The modified TCS is also utilized for the a priori signal-to-noise ratio estimation. Moreover, this paper enhances the log-spectral amplitude estimator by applying both super-Gaussian speech priors and speech presence uncertainty for further improvement. Experimental evaluations demonstrate that the proposed method yields an improvement in speech quality while maintaining modest computational and storage requirements. Furthermore, the proposed system exhibits comparable performance to several baseline systems based on lightweight deep neural networks.

12.
Adv Mater ; 36(30): e2404172, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38734973

RESUMO

Aqueous aluminum ion batteries (AAIBs) hold significant potential for grid-scale energy storage owing to their intrinsic safety, high theoretical capacity, and abundance of aluminum. However, the strong electrostatic interactions and delayed charge compensation between high-charge-density aluminum ions and the fixed lattice in conventional cathodes impede the development of high-performance AAIBs. To address this issue, this work introduces, for the first time, high-entropy Prussian blue analogs (HEPBAs) as cathodes in AAIBs with unique lattice tolerance and efficient multipath electron transfer. Benefiting from the intrinsic long-range disorder and robust lattice strain field, HEPBAs enable the manifestation of the lattice respiration effect and minimize lattice volume changes, thereby achieving one of the best long-term stabilities (91.2% capacity retention after 10 000 cycles at 5.0 A g-1) in AAIBs. Additionally, the interaction between the diverse metal atoms generates a broadened d-band and reduced degeneracy compared with conventional Prussian blue and its analogs (PBAs), which enhances the electron transfer efficiency with one of the best rate performance (79.2 mAh g-1 at 5.0 A g-1) in AAIBs. Furthermore, exceptional element selectivity in HEPBAs with unique cocktail effect can facile tune electrochemical behavior. Overall, the newly developed HEPBAs with a high-entropy effect exhibit promising solutions for advancing AAIBs and multivalent-ion batteries.

13.
J Neural Eng ; 21(2)2024 04 09.
Artigo em Inglês | MEDLINE | ID: mdl-38565124

RESUMO

Objective.Recent studies have shown that integrating inertial measurement unit (IMU) signals with surface electromyographic (sEMG) can greatly improve hand gesture recognition (HGR) performance in applications such as prosthetic control and rehabilitation training. However, current deep learning models for multimodal HGR encounter difficulties in invasive modal fusion, complex feature extraction from heterogeneous signals, and limited inter-subject model generalization. To address these challenges, this study aims to develop an end-to-end and inter-subject transferable model that utilizes non-invasively fused sEMG and acceleration (ACC) data.Approach.The proposed non-invasive modal fusion-transformer (NIMFT) model utilizes 1D-convolutional neural networks-based patch embedding for local information extraction and employs a multi-head cross-attention (MCA) mechanism to non-invasively integrate sEMG and ACC signals, stabilizing the variability induced by sEMG. The proposed architecture undergoes detailed ablation studies after hyperparameter tuning. Transfer learning is employed by fine-tuning a pre-trained model on new subject and a comparative analysis is performed between the fine-tuning and subject-specific model. Additionally, the performance of NIMFT is compared to state-of-the-art fusion models.Main results.The NIMFT model achieved recognition accuracies of 93.91%, 91.02%, and 95.56% on the three action sets in the Ninapro DB2 dataset. The proposed embedding method and MCA outperformed the traditional invasive modal fusion transformer by 2.01% (embedding) and 1.23% (fusion), respectively. In comparison to subject-specific models, the fine-tuning model exhibited the highest average accuracy improvement of 2.26%, achieving a final accuracy of 96.13%. Moreover, the NIMFT model demonstrated superiority in terms of accuracy, recall, precision, and F1-score compared to the latest modal fusion models with similar model scale.Significance.The NIMFT is a novel end-to-end HGR model, utilizes a non-invasive MCA mechanism to integrate long-range intermodal information effectively. Compared to recent modal fusion models, it demonstrates superior performance in inter-subject experiments and offers higher training efficiency and accuracy levels through transfer learning than subject-specific approaches.


Assuntos
Gestos , Reconhecimento Psicológico , Rememoração Mental , Fontes de Energia Elétrica , Redes Neurais de Computação , Eletromiografia
14.
Polymers (Basel) ; 16(7)2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38611176

RESUMO

Within the realm of dental material innovation, this study pioneers the incorporation of tung oil into polyurea coatings, setting a new precedent for enhancing self-healing functionality and durability. Originating from an ancient practice, tung oil is distinguished by its outstanding water resistance and microbial barrier efficacy. By synergizing it with polyurea, we developed coatings that unite mechanical strength with biological compatibility. The study notably quantifies self-healing efficiency, highlighting the coatings' exceptional capacity to mend physical damages and thwart microbial incursions. Findings confirm that tung oil markedly enhances the self-repair capabilities of polyurea, leading to improved wear resistance and the inhibition of microbial growth, particularly against Streptococcus mutans, a principal dental caries pathogen. These advancements not only signify a leap forward in dental material science but also suggest a potential redefinition of dental restorative practices aimed at prolonging the lifespan of restorations and optimizing patient outcomes. Although this study lays a substantial foundation for the utilization of natural oils in the development of medical-grade materials, it also identifies the critical need for comprehensive cytotoxicity assays. Such evaluations are essential to thoroughly assess the biocompatibility and the safety profile of these innovative materials for clinical application. Future research will concentrate on this aspect, ensuring that the safety and efficacy of the materials align with clinical expectations for dental restorations.

15.
J Exp Bot ; 75(10): 2917-2932, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38465908

RESUMO

Sucrose non-fermenting-1-related protein kinase 1 (SnRK1) and AMP-activated protein kinase (AMPK) are highly conserved. Compound 991 is an AMPK activator in mammals. However, whether 991 also activates SnRK1 remains unknown. The addition of 991 significantly increased SnRK1 activity in desalted extracts from germinating rice seeds in vitro. To determine whether 991 has biological activity, rice seeds were treated with different concentrations of 991. Germination was promoted at low concentrations but inhibited at high concentrations. The effects of 991 on germination were similar to those of OsSnRK1a overexpression. To explore whether 991 affects germination by specifically affecting SnRK1, germination of an snrk1a mutant and the wild type under 1 µM 991 treatment was compared. The snrk1a mutant was insensitive to 991. Phosphoproteomic analysis showed that the differential phosphopeptides induced by 991 and OsSnRK1a overexpression largely overlapped. Furthermore, SnRK1 might regulate rice germination in a dosage-dependent manner by regulating the phosphorylation of three phosphosites, namely S285-PIP2;4, S1013-SOS1, and S110-ABI5. These results indicate that 991 is a specific SnRK1 activator in rice. The promotion and inhibition of germination by 991 also occurred in wheat seeds. Thus, 991 is useful for exploring SnRK1 function and the chemical regulation of growth and development in crops.


Assuntos
Germinação , Oryza , Proteínas Serina-Treonina Quinases , Sementes , Oryza/genética , Oryza/crescimento & desenvolvimento , Oryza/metabolismo , Oryza/fisiologia , Sementes/crescimento & desenvolvimento , Sementes/genética , Sementes/metabolismo , Sementes/fisiologia , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Serina-Treonina Quinases/genética , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Proteínas Quinases Ativadas por AMP/metabolismo , Proteínas Quinases Ativadas por AMP/genética
16.
Small ; 20(29): e2312086, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38412409

RESUMO

Rechargeable aqueous aluminum batteries (AABs) are promising energy storage technologies owing to their high safety and ultra-high energy-to-price ratio. However, either the strong electrostatic forces between high-charge-density Al3+ and host lattice, or sluggish large carrier-ion diffusion toward the conventional inorganic cathodes generates inferior cycling stability and low rate-capacity. To overcome these inherent confinements, a series of promising redox-active organic materials (ROMs) are investigated and a π-conjugated structure ROMs with synergistic C═O and C═N groups is optimized as the new cathode in AABs. Benefiting from the joint utilization of multi-redox centers and rich π-π intermolecular interactions, the optimized ROMs with unique ion coordination storage mechanism facilely accommodate complex active ions with mitigated coulombic repulsion and robust lattice structure, which is further validated via theoretical simulations. Thus, the cathode achieves enhanced rate performance (153.9 mAh g-1 at 2.0 A g-1) and one of the best long-term stabilities (125.7 mAh g-1 after 4,000 cycles at 1.0 A g-1) in AABs. Via molecular exploitation, this work paves the new direction toward high-performance cathode materials in aqueous multivalent-ion battery systems.

18.
BMC Genomics ; 24(1): 617, 2023 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-37848864

RESUMO

BACKGROUND: Oculomotor nerve palsy (ONP) is a neuroparalytic disorder resulting in dysfunction of innervating extraocular muscles (EOMs), of which the pathological characteristics remain underexplored. METHODS: In this study, medial rectus muscle tissue samples from four ONP patients and four constant exotropia (CXT) patients were collected for RNA sequencing. Differentially expressed circular RNAs (circRNAs) were identified and included in functional enrichment analysis, followed by interaction analysis with microRNAs and mRNAs as well as RNA binding proteins. Furthermore, RT-qPCR was used to validate the expression level of the differentially expressed circRNAs. RESULTS: A total of 84 differentially expressed circRNAs were identified from 10,504 predicted circRNAs. Functional enrichment analysis indicated that the differentially expressed circRNAs significantly correlated with skeletal muscle contraction. In addition, interaction analyses showed that up-regulated circRNA_03628 was significantly interacted with RNA binding protein AGO2 and EIF4A3 as well as microRNA hsa-miR-188-5p and hsa-miR-4529-5p. The up-regulation of circRNA_03628 was validated by RT-qPCR, followed by further elaboration of the expression, location and clinical significance of circRNA_03628 in EOMs of ONP. CONCLUSIONS: Our study may shed light on the role of differentially expressed circRNAs, especially circRNA_03628, in the pathological changes of EOMs in ONP.


Assuntos
MicroRNAs , RNA Circular , Humanos , RNA Circular/genética , Músculos Oculomotores/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Regulação para Cima , Análise de Sequência de RNA , Fator de Iniciação 4A em Eucariotos/genética , Fator de Iniciação 4A em Eucariotos/metabolismo , RNA Helicases DEAD-box/genética , RNA Helicases DEAD-box/metabolismo
19.
Adv Mater ; 35(51): e2301538, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37876329

RESUMO

The strong electrostatic interaction between high-charge-density zinc ions (112 C mm-3 ) and the fixed crystallinity of traditional oxide cathodes with delayed charge compensation hinders the development of high-performance aqueous zinc-ion batteries (AZIBs). Herein, to intrinsically promote electron transfer efficiency and improve lattice tolerance, a revolutionary family of high-entropy oxides (HEOs) materials with multipath electron transfer and remarkable structural stability as cathodes for AZIBs is proposed. Benefiting from the unique "cock-tail" effect, the interaction of diverse type metal-atoms in HEOs achieves essentially broadened d-band and lower degeneracy than monometallic oxides, which contribute to convenient electron transfer and one of the best rate-performances (136.2 mAh g-1 at 10.0 A g-1 ) in AZIBs. In addition, the intense lattice strain field of HEOs is highly tolerant to the electrostatic repulsion of high-charge-density Zn2+ , leading to the outstanding cycling stability in AZIBs. Moreover, the super selectability of elements in HEOs exhibits significant potential for AZIBs.

20.
Plant Physiol Biochem ; 203: 108048, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37757719

RESUMO

The redistribution of nonstructural carbohydrates (NSCs) in rice (Oryza sativa) sheaths contributes greatly to grain filling. Sucrose nonfermenting-1-related protein kinase 1 (SnRK1) regulates sheath-to-panicle transport of NSCs during rice grain filling; however, it is unknown whether elevated activity of SnRK1 in sheaths improves NSC transport and grain filling. Expression of OsSnRK1a is mainly responsible for regulating SnRK1 activity in rice sheaths. Analysis of transgenic rice plants containing the OsSnRK1a promoter::GUS construct indicated that OsSnRK1a is widely expressed in rice. Notably, OsSnRK1a is highly expressed in mesophyll cells of sheaths. Therefore, a green tissue promoter specifically expressed in sheaths and leaf parenchyma cells and phloem tissue was used to over-express OsSnRK1a in japonica rice. The transgenic lines exhibited increased SnRK1a expression and SnRK1 activity in sheaths. The NSC and starch in the transgenic lines and WT all showed accumulation before heading and during the early-filling stage, and declining at the peak filling stage. But the starch and NSC content in transgenic lines was lower than that of WT. Moreover, the transgenic lines showed lower sucrose contents and higher sucrose efflux rates. The accelerated sheath NSC transport improved grain filling, and stimulated panicle development in transgenic lines. SnRK1a expression and SnRK1 activity were also increased in the leaves of transgenic lines, which improved leaf photosynthetic activity and contributed to optimal grain filling and panicle development. These results verify the promotion of high SnRK1 activity in sheath NSC transport, and also provide a new approach to improving sheath NSC transport and rice yield.

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