Publications by authors named "Guohua Xu"

215 Publications

Rolipram plays an anti-fibrotic effect in ligamentum flavum fibroblasts by inhibiting the activation of ERK1/2.

BMC Musculoskelet Disord 2021 Sep 23;22(1):818. Epub 2021 Sep 23.

Department of Orthopedics, Changzheng Hospital, Naval Medical University, Shanghai, 200003, People's Republic of China.

Background: Fibrosis is an important factor and process of ligamentum flavum hypertrophy. The expression of phosphodiesterase family (PDE) is related to inflammation and fibrosis. This article studied the expression of PDE in hypertrophic ligamentum flavum fibroblasts and investigated whether inhibition of PDE4 activity can play an anti-fibrotic effect.

Methods: Samples of clinical hypertrophic ligamentum flavum were collected and patients with lumbar disc herniations as a control group. The collagenase digestion method is used to separate fibroblasts. qPCR is used to detect the expression of PDE subtypes, type I collagen (Col I), type III collagen (Col III), fibronectin (FN1) and transforming growth factor β1 (TGF-β1). Recombinant TGF-β1 was used to stimulate fibroblasts to make a fibrotic cell model and treated with Rolipram. The morphology of the cells treated with drugs was observed by Sirius Red staining. Scratch the cells to observe their migration and proliferation. WB detects the expression of the above-mentioned multiple fibrotic proteins after drug treatment. Finally, combined with a variety of signaling pathway drugs, the signaling mechanism was studied.

Results: Multiple PDE subtypes were expressed in ligamentum flavum fibroblasts. The expression of PDE4A and 4B was significantly up-regulated in the hypertrophic group. Using Rolipram to inhibit PDE4 activity, the expression of Col I and TGF-β1 in the hypertrophic group was inhibited. Col I recovered to the level of the control group. TGF-β1 was significantly inhibited, which was lower than the control group. Recombinant TGF-β1 stimulated fibroblasts to increase the expression of Col I/III, FN1 and TGF-β1, which was blocked by Rolipram. Rolipram restored the increased expression of p-ERK1/2 stimulated by TGF-β1.

Conclusion: The expressions of PDE4A and 4B in the hypertrophic ligamentum flavum are increased, suggesting that it is related to the hypertrophy of the ligamentum flavum. Rolipram has a good anti-fibrosis effect after inhibiting the activity of PDE4. This is related to blocking the function of TGF-β1, specifically by restoring normal ERK1/2 signal.
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http://dx.doi.org/10.1186/s12891-021-04712-9DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8461931PMC
September 2021

Treatment of thoracolumbar fractures by temporary posterior instrumentation with selective fusion schemes.

Br J Neurosurg 2021 Sep 15:1-8. Epub 2021 Sep 15.

Department of Orthopedic Surgery, Spine Center, Second Affiliated Hospital of Naval Medical University, Shanghai, P. R. China.

Objective: This retrospective study investigated the clinical and radiographic outcomes following temporary transpedicular posterior instrumentation between two cohorts of patients with thoracolumbar fractures (TLF) who underwent selective or bi-segments intervertebral articular process fusion.

Methods: Patients with TLF who underwent the temporary posterior fixation with selective fusion (Group SF), or bi-segments fusion (Group BF) were studied. Superior intervertebral articular process and interlaminar fusion were performed in Group SF, whereas in Group BF, the patients underwent bi-segments fusion in both superior and inferior articular processes, as well as interlaminar fusion. We measured the distal and proximal intervertebral mobility, regional kyphotic angle, and vertebral height before and after surgery in both groups. Greenough Low-Back Outcome Score was used to assess the clinical outcomes.

Results: Sixty-five patients with TLF from T12 to L2 fractures were enrolled in the study period: 33 patients in the Group SF and 32 patients in the Group BF. All the patients experienced fracture healing (mean follow-up time: 19.7 months). The mean postoperative functional outcomes were 65.0 ± 2.0 points for the Low-Back Outcome Score in the Group SF and 65.2 ± 1.8 for the Group BF. A progressive regional kyphotic angle was observed with time regardless of fusion but was not significantly different between the two groups. There was a statistical difference between unfused inferior proximal adjacent and inferior distal adjacent segment regardless of fracture segments.

Conclusions: The strategy of selective fusion is reported to be useful for the treatment of patients with TLF. The motion in the un-fused and adjacent segment could be better regained after instrumentation removal in the selective fusion group.

Level Of Evidence: Level 3.
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http://dx.doi.org/10.1080/02688697.2021.1976391DOI Listing
September 2021

OsWRKY108 is an integrative regulator of phosphorus homeostasis and leaf inclination in rice.

Plant Signal Behav 2021 Sep 15:1976545. Epub 2021 Sep 15.

State Key Laboratory of Crop Genetics and Germplasm Enhancement, Nanjing Agricultural University, Nanjing, China.

Phosphorus (P), which is taken up by plants as inorganic phosphate (Pi), is one of the most important macronutrients for plant growth and development. Meanwhile, it determines plant architecture in several ways, including leaf inclination. However, the molecular basis underlying the crosstalk between the signaling pathways of plant P homeostasis and architecture maintenance remains elusive. We recently characterized a WRKY transcription factor, OsWRKY108, in rice (). It functions redundantly with OsWRKY21 to promote Pi uptake in response to Pi supply. Overexpression of either or led to up-regulation of Pi transporter genes and thus enhanced Pi accumulation. By contrast, transgenic rice plants expressing OsWRKY21-SRDX (a fusion protein transforming OsWRKY21 from an activator into a dominant repressor) but not the OsWRKY108-SRDX fusion showed decreased Pi accumulation under Pi-replete conditions. Here, we report that OsWRKY108 acts as a positive regulator of leaf inclination. overexpressors showed increased leaf inclination and plants showed an erect-leaf phenotype, irrespective of the Pi regimes. Nevertheless, the response of leaf inclination to Pi starvation was largely impaired upon overexpression. Moreover, in both plants and overexpressors, the 'percentage of leaf angle alteration relative to wild-type' under Pi-starvation condition was more significant than that under Pi-replete condition. These results suggest that the regulation of OsWRKY108 on leaf inclination is in part dependent on Pi availability. Altogether, our findings demonstrate that OsWRKY108 is an integrative regulator of P homeostasis and leaf inclination, serving as a link between plant nutrient signaling and developmental cues.
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http://dx.doi.org/10.1080/15592324.2021.1976545DOI Listing
September 2021

Marine-Derived Collagen as Biomaterials for Human Health.

Front Nutr 2021 24;8:702108. Epub 2021 Aug 24.

Key Laboratory of Resource Biology and Biotechnology in Western China, Department of Life Sciences and Medicine, Ministry of Education, School of Medicine, Northwest University, Xi'an, China.

Collagen is a kind of biocompatible protein material, which is widely used in medical tissue engineering, drug delivery, cosmetics, food and other fields. Because of its wide source, low extraction cost and good physical and chemical properties, it has attracted the attention of many researchers in recent years. However, the application of collagen derived from terrestrial organisms is limited due to the existence of diseases, religious beliefs and other problems. Therefore, exploring a wider range of sources of collagen has become one of the main topics for researchers. Marine-derived collagen (MDC) stands out because it comes from a variety of sources and avoids issues such as religion. On the one hand, this paper summarized the sources, extraction methods and characteristics of MDC, and on the other hand, it summarized the application of MDC in the above fields. And on the basis of the review, we found that MDC can not only be extracted from marine organisms, but also from the wastes of some marine organisms, such as fish scales. This makes further use of seafood resources and increases the application prospect of MDC.
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http://dx.doi.org/10.3389/fnut.2021.702108DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8421607PMC
August 2021

HIF-1-Mediated miR-623 Regulates Apoptosis and Inflammatory Responses of Nucleus Pulposus Induced by Oxidative Stress via Targeting TXNIP.

Oxid Med Cell Longev 2021 3;2021:6389568. Epub 2021 Aug 3.

Department of Orthopedic Surgery, Spine Center, Shanghai Changzheng Hospital, The Second Military Medical University, Shanghai, China.

Excessive apoptosis and inflammatory responses of nucleus pulposus (NP) cells induced by oxidative stress contribute to intervertebral disc degeneration (IVDD). Though some microRNAs are associated with IVDD, the specific microRNA that can mediate apoptotic and inflammatory responses of NP cells induced by oxidative stress synchronously still needs further identification. Here, we find that microRNA-623 (miR-623) is downregulated in IVDD and its expression is regulated by hypoxia-inducible factor-1 (HIF-1) under oxidative stress conditions. Mechanistically, HIF-1 is observed to promote miR-623 expression by directly binding to its promoter region (-1,994/-1,987 bp). Functionally, miR-623 is found to work as an intermediator in alleviating apoptosis and inflammatory responses of NP cells induced by oxidative stress via regulating thioredoxin-interacting protein () expression by directly targeting its 3'-untranslated region (3'-UTR). Thus, on elucidating the expression and functional mechanisms of miR-623, our study suggests that miR-623 can be a valuable therapeutic target for treating oxidative stress-induced IVDD.
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http://dx.doi.org/10.1155/2021/6389568DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8355979PMC
August 2021

Clinical and radiological outcomes of endoscopic foraminoplasty and decompression assisted with preoperative planning software for lumbar foraminal stenosis.

Int J Comput Assist Radiol Surg 2021 Jul 29. Epub 2021 Jul 29.

Department of Spine Surgery, Changzheng Hospital, Second Military Medical University, 415 Fengyang Road, Shanghai, 200003, People's Republic of China.

Purpose: To assess the clinical and radiological outcomes of using endoscopic foraminoplasty and decompression assisted with a preoperative planning software in the treatment of lumbar foraminal stenosis.

Methods: This retrospective study included 43 patients with lumbar foraminal stenosis (Jan 2018 and June 2019). These patients were divided into two groups. Patients in the conventional group (group A) underwent endoscopic lumbar foraminoplasty and decompression. Patients in the experimental group (group B) underwent the same surgery assisted with a preoperative software. The total operation time, puncture-channel establishment time, and the number of intraoperative fluoroscopic images taken were recorded. The Visual Analog Scale (VAS) and Oswestry Disability Index (ODI) were administered preoperatively and postoperatively (at 1-month, 3-month, and 12-month follow-up). The modified MacNab criteria were used to assess the global outcome at 12-month follow-up.

Results: Patients in group B had shorter operation time, puncture-channel establishment time, and less number of intraoperative fluoroscopic images taken, as compared with group A. The VAS and ODI scores were significantly lower than pre-operation for both groups at all follow-ups. No significant difference was observed between these two groups. Based on the modified MacNab criteria, the excellent-to-good rate was 86.4% in group A and 90.5% in group B, respectively. After the operation, no patients had residual osteophytes in group B, while two patients still had residual osteophytes and foraminal stenosis in group A.

Conclusion: For endoscopic surgery treating lumbar foraminal stenosis, using preoperative planning software could reduce the puncture-channel establishment time, operation time, and the number of intraoperative fluoroscopic images taken without affecting the clinical outcomes.
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http://dx.doi.org/10.1007/s11548-021-02453-7DOI Listing
July 2021

Recent advances in the epigenetics of bone metabolism.

J Bone Miner Metab 2021 Jul 11. Epub 2021 Jul 11.

Key Laboratory of Metabolism and Molecular Medicine, Ministry of Education, Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Fudan University, Shanghai, China.

Osteoporosis is a common form of metabolic bone disease that is costly to treat and is primarily diagnosed on the basis of bone mineral density. As the influences of genetic lesions and environmental factors are increasingly studied in the pathological development of osteoporosis, regulated epigenetics are emerging as the important pathogenesis mechanisms in osteoporosis. Recently, osteoporosis genome-wide association studies and multi-omics technologies have revealed that susceptibility loci and the misregulation of epigenetic modifiers are key factors in osteoporosis. Over the past decade, extensive studies have demonstrated epigenetic mechanisms, such as DNA methylation, histone/chromatin modifications, and non-coding RNAs, as potential contributing factors in osteoporosis that affect disease initiation and progression. Herein, we review recent advances in epigenetics in osteoporosis, with a focus on exploring the underlying mechanisms and potential diagnostic/prognostic biomarker applications for osteoporosis.
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http://dx.doi.org/10.1007/s00774-021-01249-8DOI Listing
July 2021

Mussel-Inspired Bisphosphonated Injectable Nanocomposite Hydrogels with Adhesive, Self-Healing, and Osteogenic Properties for Bone Regeneration.

ACS Appl Mater Interfaces 2021 Jul 6;13(28):32673-32689. Epub 2021 Jul 6.

Department of Polymer Materials, School of Materials Science and Engineering, Shanghai University, Shanghai 200444, PR China.

Injectable hydrogels have received much attention because of the advantages of simulation of the natural extracellular matrix, microinvasive implantation, and filling and repairing of complex shape defects. Yet, for bone repair, the current injectable hydrogels have shown significant limitations such as the lack of tissue adhesion, deficiency of self-healing ability, and absence of osteogenic activity. Herein, a strategy to construct mussel-inspired bisphosphonated injectable nanocomposite hydrogels with adhesive, self-healing, and osteogenic properties is developed. The nano-hydroxyapatite/poly(l-glutamic acid)-dextran (nHA/PLGA-Dex) dually cross-linked (DC) injectable hydrogels are fabricated via Schiff base cross-linking and noncovalent nHA-BP chelation. The chelation between bisphosphonate ligands (alendronate sodium, BP) and nHA favors the uniform dispersion of the latter. Moreover, multiple adhesion ligands based on catechol motifs, BP, and aldehyde groups endow the hydrogels with good tissue adhesion. The hydrogels possess excellent biocompatibility and the introduction of BP and nHA both can effectively promote viability, proliferation, migration, and osteogenesis differentiation of MC3T3-E1 cells. The incorporation of BP groups and HA nanoparticles could also facilitate the angiogenic property of endothelial cells. The nHA/PLGA-Dex DC hydrogels exhibited considerable biocompatibility despite the presence of a certain degree of inflammatory response in the early stage. The successful healing of a rat cranial defect further proves the bone regeneration ability of nHA/PLGA-Dex DC injectable hydrogels. The developed tissue adhesive osteogenic injectable nHA/PLGA-Dex hydrogels show significant potential for bone regeneration application.
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http://dx.doi.org/10.1021/acsami.1c06058DOI Listing
July 2021

Overexpression of OsPHR3 improves growth traits and facilitates nitrogen use efficiency under low phosphate condition.

Plant Physiol Biochem 2021 Sep 24;166:712-722. Epub 2021 Jun 24.

State Key Laboratory of Crop Genetics and Germplasm Enhancement, Key Laboratory of Plant Nutrition and Fertilization in Low-Middle Reaches of the Yangtze River, Ministry of Agriculture and Rural Affairs, Nanjing Agricultural University, Nanjing, 210095, China. Electronic address:

Phosphorus (P) and nitrogen (N) are both essential macronutrients for maintaining plant growth and development. In rice (Oryza sativa L.), OsPHR3 is one of the four paralogs of PHR1, which acts as a central regulator of phosphate (Pi) homeostasis, as well being involved in N homeostasis. However, the functions of OsPHR3 in N utilization under different Pi conditions have yet to be fully studied. In this study, we aimed to dissect the effect of OsPHR3-overexpression on N utilization under Pi deficient regimes. Biochemical, molecular and physiological assays were performed to determine the N-influx, translocation, and accumulation in OsPHR3-overexpressing rice lines, grown under Pi-sufficient and -deficient conditions, in both hydroponic and soil systems. Furthermore, important agronomic traits of these plants were also evaluated. The overexpression of OsPHR3 increased N uptake under Pi stress regimes. Increased N uptake also elevated total N concentrations in these plants by inducing N transporter genes expression. Furthermore, overexpression of OsPHR3 increased N use efficiency, 1000-grain weight and grain yield under different Pi conditions. We established new findings that OsPHR3-overexpression facilitates N utilization under Pi deficient conditions. This will help achieving higher yields by coordinating the utilization of N and P.
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http://dx.doi.org/10.1016/j.plaphy.2021.06.041DOI Listing
September 2021

Clinical Outcomes of Posterior Percutaneous Endoscopic Cervical Foraminotomy and Discectomy Assisted with SNRB in Treating Cervical Radiculopathy with Diagnostic Uncertainty.

Pain Physician 2021 07;24(4):E483-E492

Department of Orthopedic Surgery, Changzheng Hospital, Second Military Medical University, Shanghai, China.

Background: Selective nerve root block (SNRB) has been used to facilitate the diagnostic process when radiologic abnormalities are not correlated with clinical symptomatology in patients with cervical radiculopathy. Meanwhile, minimally invasive posterior percutaneous endoscopic cervical foraminotomy and discectomy (PPECFD) has been widely used to treat cervical radiculopathy because of its advantages. However, combination of these 2 procedures in the treatment of cervical radiculopathy with diagnostic uncertainty has not been reported.

Objectives: To examine the clinical outcomes of PPECFD assisted with SNRB in patients who had cervical radiculopathy with diagnostic uncertainty.

Study Design: A retrospective design was used.

Setting: This study was conducted in a university-affiliated tertiary hospital in Shanghai, China.

Methods: Thirty consecutive patients with cervical radicular pain who had diagnostic uncertainty were included (January 2018 to January 2019). Diagnostic SNRB was performed to identify the responsible nerve root(s). PPECFD was selected as the treatment when the SNRB result was positive. Clinical outcomes were assessed by the Visual Analog Scale (VAS), Neck Disability Index (NDI), and modified Macnab criteria. Pre- and post-operative radiologic and clinical parameters were evaluated. Other information was retrieved from the electronic records.

Results: All patients had successful SNRB procedures. Four were excluded from the analysis because of the negative results of the SNRB. Among the remaining 26 patients who underwent the subsequent PPECFD surgery, the mean follow-up was 14 months. Compared with preoperative values, the mean VAS scores for radicular arm pain and neck pain, as well as the NDI score, improved significantly. According to the Macnab criteria, 22 patients (84.6%) had excellent or good results. No major peri- and postoperative complications were observed.

Limitations: This study used a retrospective design with relatively small sample size and medium follow-up duration.

Conclusions: Diagnostic SNRB may be a helpful tool to identify the origin of cervical radicular pain for patients with diagnostic uncertainty. With the guidance of SNRB, PPECFD is likely to be an effective and safe option for the treatment of cervical radiculopathy with diagnostic uncertainty.
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July 2021

NMR backbone resonance assignment of Japanese encephalitis virus capsid protein.

Biomol NMR Assign 2021 Oct 25;15(2):403-407. Epub 2021 Jun 25.

Key Laboratory of Magnetic Resonance in Biological Systems, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, National Center for Magnetic Resonance in Wuhan, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, Wuhan, 430071, People's Republic of China.

Japanese encephalitis virus (JEV) is a flavivirus in the same family as West Nile virus (WNV), dengue virus (DENV) and yellow fever virus (YFV), which are transmitted by mosquitoes. About 68 thousand people are infected with JEV every year. In many Asian countries, JEV is the main cause of viral encephalitis. There are no specific antiviral drugs for Japanese encephalitis. Capsid protein C is the core protein of virus particles. Many studies have revealed that capsid protein C plays an important role in the life cycle of flaviviruses. Although the structure of JEV capsid protein (JEVC) has been determined by X-ray crystallography, the mechanism of how it assembles into an inner core to encapsulate the virus genome remains elusive. What's more, the disordered N-terminal region that is reported to affect its assembly is absent in the crystal structure. NMR spectroscopy has distinct advantages over other technologies in the characterization of conformational dynamics. Here we report the backbone H, C and N chemical shift assignments of JEVC by heteronuclear multidimensional spectroscopy and predict its secondary structure in solution using TALOS+.
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http://dx.doi.org/10.1007/s12104-021-10037-4DOI Listing
October 2021

Backbone resonance assignment of PDI b'xa' domain construct.

Biomol NMR Assign 2021 Oct 24;15(2):409-413. Epub 2021 Jun 24.

Key Laboratory of Magnetic Resonance in Biological Systems, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, National Center for Magnetic Resonance in Wuhan, Wuhan Institute of Physics and Mathematics, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, Wuhan, 430071, People's Republic of China.

Human protein disulfide isomerase (PDI), a protein containing 4 domains a, b, b', a', disordered x linker and C-terminus, plays critical roles in disulfide bond reactions and proper protein folding in the endoplasmic reticulum. The bb' domain contributes to client binding, the a, a' domain catalyse the rearrangement of the disulfide bonds. The x linker and a' domain were the main dynamics region for full-length PDI and the b'xa' construct has the minimum functional domain within full-length PDI. Herein, we report a new preparation strategy with 1, 6-hexandiol and backbone NMR chemical shift assignments for the monomer b'xa' domain.
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http://dx.doi.org/10.1007/s12104-021-10038-3DOI Listing
October 2021

Sulfoquinovosyl diacylglycerol synthase 1 impairs glycolipid accumulation and photosynthesis in phosphate-deprived rice.

J Exp Bot 2021 Sep;72(18):6510-6523

Institute of Eco-Environment and Plant Protection, Shanghai Academy of Agricultural Sciences, Shanghai, 201403,China.

Phosphate (Pi)-starved crops utilize phospholipids as a source for internal Pi supply by replacing non-phosphorus glycolipids. In rice, sulfoquinovosyl diacylglycerol synthase 1 (OsSQD1) functions as a key enzyme in the first step to catalyze sulfoquinovosyldiacylglycerol (SQDG) formation. Here we study differential expression of OsSQD1 in response to Pi, nitrogen, potassium, and iron-deficiencies in rice. Electrophoretic mobility shift assay suggested that OsSQD1 is regulated by OsPHR2 (Phosphate Starvation Response2), a MYB (v-myb avian myeloblastosis viral oncogene homolog) domain-containing transcription factor. The concentrations of different lipid species in ossqd1 knockout mutant demonstrated that OsSQD1 silencing increased the phospholipid content and altered fatty acid composition under Pi-deficiency. Moreover, OsSQD1 silencing reduces glycolipid accumulation under Pi-deficiency, and triggered the saturation of fatty acids in phospholipids and glycolipids treated with different Pi regimes. Relative amounts of transcripts related to phospholipid degradation and glycolipid synthesis were assessed to explore the mechanism by which OsSQD1 exerts an effect on lipid homeostasis under P-deficiency. Furthermore, OsSQD1 silencing inhibited photosynthesis, especially under Pi-deficient conditions, by down-regulating glycolipids in rice shoots. Taken together, our study reveals that OsSQD1 plays a key role in lipid homeostasis, especially glycolipid accumulation under Pi-deficiency, which results in the inhibition of photosynthesis.
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http://dx.doi.org/10.1093/jxb/erab300DOI Listing
September 2021

Injectable and thermosensitive hydrogels mediating a universal macromolecular contrast agent with radiopacity for noninvasive imaging of deep tissues.

Bioact Mater 2021 Dec 23;6(12):4717-4728. Epub 2021 May 23.

State Key Laboratory of Molecular Engineering of Polymers, Department of Macromolecular Science, Shanghai Stomatological Hospital, Fudan University, Shanghai, 200438, China.

It is very challenging to visualize implantable medical devices made of biodegradable polymers in deep tissues. Herein, we designed a novel macromolecular contrast agent with ultrahigh radiopacity (iodinate content > 50%) via polymerizing an iodinated trimethylene carbonate monomer into the two ends of poly(ethylene glycol) (PEG). A set of thermosensitive and biodegradable polyester-PEG-polyester triblock copolymers with varied polyester compositions synthesized by us, which were soluble in water at room temperature and could spontaneously form hydrogels at body temperature, were selected as the demonstration materials. The addition of macromolecular contrast agent did not obviously compromise the injectability and thermogelation properties of polymeric hydrogels, but conferred them with excellent X-ray opacity, enabling visualization of the hydrogels at clinically relevant depths through X-ray fluoroscopy or Micro-CT. In a mouse model, the 3D morphology of the radiopaque hydrogels after injection into different target sites was visible using Micro-CT imaging, and their injection volume could be accurately obtained. Furthermore, the subcutaneous degradation process of a radiopaque hydrogel could be non-invasively monitored in a real-time and quantitative manner. In particular, the corrected degradation curve based on Micro-CT imaging well matched with the degradation profile of virgin polymer hydrogel determined by the gravimetric method. These findings indicate that the macromolecular contrast agent has good universality for the construction of various radiopaque polymer hydrogels, and can nondestructively trace and quantify their degradation . Meanwhile, the present methodology developed by us affords a platform technology for deep tissue imaging of polymeric materials.
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http://dx.doi.org/10.1016/j.bioactmat.2021.05.013DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8165329PMC
December 2021

Plant DNA methylation is sensitive to parent seed N content and influences the growth of rice.

BMC Plant Biol 2021 May 11;21(1):211. Epub 2021 May 11.

State Key Laboratory of Crop Genetics and Germplasm Enhancement, MOA Key Laboratory of Plant Nutrition and Fertilization in Low-Middle Reaches of the Yangtze River, Nanjing Agricultural University, Nanjing, 210095, China.

Background: Nitrogen (N) is an important nutrient for plant growth, development, and agricultural production. Nitrogen stress could induce epigenetic changes in plants. In our research, overexpression of the OsNAR2.1 line was used as a testing target in rice plants with high nitrogen-use efficiency to study the changes of rice methylation and growth in respond of the endogenous and external nitrogen stress.

Results: Our results showed that external N deficiency could decrease seed N content and plant growth of the overexpression line. During the filial growth, we found that the low parent seed nitrogen (LPSN) in the overexpression line could lead to a decrease in the filial seed nitrogen content, total plant nitrogen content, yield, and OsNAR2.1 expression (28, 35, 23, and 55%, respectively) compared with high parent seed nitrogen (HPSN) in high nitrogen external supply. However, such decreases were not observed in wild type. Furthermore, methylation sequencing results showed that LPSN caused massive gene methylation changes, which enriched in over 20 GO pathways in the filial overexpression line, and the expression of OsNAR2.1 in LPSN filial overexpression plants was significantly reduced compared to HPSN filial plants in high external N, which was not shown in wild type.

Conclusions: We suggest that the parent seed nitrogen content decreased induced DNA methylation changes at the epigenetic level and significantly decreased the expression of OsNAR2.1, resulting in a heritable phenotype of N deficiency over two generations of the overexpression line.
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http://dx.doi.org/10.1186/s12870-021-02953-3DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8111971PMC
May 2021

Modulation of plant root traits by nitrogen and phosphate: transporters, long-distance signaling proteins and peptides, and potential artificial traps.

Breed Sci 2021 Feb 25;71(1):62-75. Epub 2020 Dec 25.

State Key Laboratory of Crop Genetics and Germplasm Enhancement, Nanjing Agricultural University, Nanjing 210095, China.

As sessile organisms, plants rely on their roots for anchorage and uptake of water and nutrients. Plant root is an organ showing extensive morphological and metabolic plasticity in response to diverse environmental stimuli including nitrogen (N) and phosphorus (P) nutrition/stresses. N and P are two essential macronutrients serving as not only cell structural components but also local and systemic signals triggering root acclimatory responses. Here, we mainly focused on the current advances on root responses to N and P nutrition/stresses regarding transporters as well as long-distance mobile proteins and peptides, which largely represent local and systemic regulators, respectively. Moreover, we exemplified some of the potential pitfalls in experimental design, which has been routinely adopted for decades. These commonly accepted methods may help researchers gain fundamental mechanistic insights into plant intrinsic responses, yet the output might lack strong relevance to the real situation in the context of natural and agricultural ecosystems. On this basis, we further discuss the established-and yet to be validated-improvements in experimental design, aiming at interpreting the data obtained under laboratory conditions in a more practical view.
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http://dx.doi.org/10.1270/jsbbs.20102DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7973493PMC
February 2021

Plasma membrane H-ATPase overexpression increases rice yield via simultaneous enhancement of nutrient uptake and photosynthesis.

Nat Commun 2021 02 2;12(1):735. Epub 2021 Feb 2.

Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization, College of Resources and Environment Sciences, Nanjing Agricultural University, Nanjing, China.

Nitrogen (N) and carbon (C) are essential elements for plant growth and crop yield. Thus, improved N and C utilisation contributes to agricultural productivity and reduces the need for fertilisation. In the present study, we find that overexpression of a single rice gene, Oryza sativa plasma membrane (PM) H-ATPase 1 (OSA1), facilitates ammonium absorption and assimilation in roots and enhanced light-induced stomatal opening with higher photosynthesis rate in leaves. As a result, OSA1 overexpression in rice plants causes a 33% increase in grain yield and a 46% increase in N use efficiency overall. As PM H-ATPase is highly conserved in plants, these findings indicate that the manipulation of PM H-ATPase could cooperatively improve N and C utilisation, potentially providing a vital tool for food security and sustainable agriculture.
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http://dx.doi.org/10.1038/s41467-021-20964-4DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7854686PMC
February 2021

Expressing Phosphate Transporter PvPht2;1 Enhances P Transport to the Chloroplasts and Increases Arsenic Tolerance in .

Environ Sci Technol 2021 02 26;55(4):2276-2284. Epub 2021 Jan 26.

Institute of Soil and Water Resources and Environmental Science, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, Zhejiang 310058, China.

Arsenic (As) contamination in soils is of great concerns due to its toxicity to plants. As an analogue, phosphorus plays an important role in protecting plants from As toxicity. In this study, we identified a new phosphate transporter 2 (PHT2), PvPht2;1, from As-hyperaccumulator and analyzed its functions in As and P transport in a yeast mutant, and model plant . PvPht2;1 contained 12 transmembrane domains, sharing high identity with PHT2 genes in diverse plants. Further, independent of external P or As levels, was mainly expressed in fronds with the expression being 3-4 folds higher than that in the roots and rhizomes. Localized to the chloroplasts based on GFP-fused PvPht2;1 in model plant tobacco, PvPht2;1 functioned as a low-affinity P transporter. Under As exposure, PvPht2;1 yeast transformants showed comparable growth with the control while high-affinity P transporter PvPht1;3 transformants showed better growth, suggesting that PvPht2;1 transported P but slower than PvPht1;3 transporter. Expressing in increased its shoot P concentration without influencing its As accumulation. Further, the chloroplasts' P content in transgenic increased by 37-59% than wild-type (WT) plants. Under As exposure, the photosynthesis of -expressing remained stable but that of WT plants decreased. The data indicate that, under As stress, expressing in enhanced its P transport to the chloroplasts and protected its photosynthesis. In short, highly expressed in the fronds and not impacted by As exposure, chloroplast-located may have protected As-hyperaccumulator from As toxicity by efficiently transporting only P to its chloroplasts.
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http://dx.doi.org/10.1021/acs.est.0c03316DOI Listing
February 2021

The Potassium Transporter OsHAK5 Alters Rice Architecture via ATP-Dependent Transmembrane Auxin Fluxes.

Plant Commun 2020 Sep 29;1(5):100052. Epub 2020 Apr 29.

State Key Laboratory of Crop Genetics and Germplasm Enhancement, MOA Key Laboratory of Plant Nutrition and Fertilization in Lower-Middle Reaches of the Yangtze River, Nanjing Agricultural University, Nanjing 210095, China.

Plant HAK/KUP/KT family members function as plasma membrane (PM) H/K symporters and may modulate chemiosmotically-driven polar auxin transport (PAT). Here, we show that inactivation of , a rice K transporter gene, decreased rootward and shootward PAT, tiller number, and the length of both lateral roots and root hairs, while overexpression increased PAT, tiller number, and root hair length, irrespective of the K supply. Inhibitors of ATP-binding-cassette type-B transporters, NPA and BUM, abolished the -overexpression effect on PAT. The mechanistic basis of these changes included the OsHAK5-mediated decrease of transmembrane potential (depolarization), increase of extracellular pH, and increase of PM-ATPase activity. These findings highlight the dual roles of OsHAK5 in altering cellular chemiosmotic gradients (generated continuously by PM H-ATPase) and regulating ATP-dependent auxin transport. Both functions may underlie the prominent effect of OsHAK5 on rice architecture, which may be exploited in the future to increase crop yield via genetic manipulations.
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http://dx.doi.org/10.1016/j.xplc.2020.100052DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7747981PMC
September 2020

Setting Characteristics and High Compressive Strength of an Anti-washout, Injectable Calcium Phosphate Cement Combined with Thermosensitive Hydrogel.

Materials (Basel) 2020 Dec 17;13(24). Epub 2020 Dec 17.

Department of Orthopedic Surgery, Spine Center, Naval Medical University, Shanghai 200003, China.

In this work, a thermosensitive poly(D,L-lactide-co-glycolide)-poly(ethylene glycol)-poly(D,L-lactide-co-glycolide) (PLGA-PEG-PLGA) hydrogel was introduced into calcium phosphate cement (CPC) to enhance the anti-washout property of CPC. The effects of the hydrogel on the setting time, injectability, anti-washout property and compressive strength of CPC were thoroughly investigated. The results showed that the hydrogel significantly increased the injectability and anti-washout property of CPC, meanwhile maintained the setting time with an acceptable range. Moreover, the hydrogel improved the initial compressive strength of CPC. The composite cement with 20% / hydrogel in the liquid phase showed fine crystals of hydration product, a more compact microstructure and lower porosity compared with control CPC. The analysis of X-ray diffraction (XRD), infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS) indicated that suitable volume ratio of hydrogel (20% /) in the setting liquid of CPC could promote the formation of hydroxyapatite in the early hydration period. The degradation behavior of the cement was characterized by immersion tests in simulated body fluid. The hydrogel had no adverse effect on the degradation rate of CPC over the immersion period of 23 days. This study indicated that incorporating PLGA-PEG-PLGA hydrogel could be a promising strategy to reinforce the handing properties and initial compressive strength of calcium phosphate cement.
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http://dx.doi.org/10.3390/ma13245779DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7766756PMC
December 2020

Nitrogen Mediates Flowering Time and Nitrogen Use Efficiency via Floral Regulators in Rice.

Curr Biol 2021 02 4;31(4):671-683.e5. Epub 2020 Dec 4.

State Key Laboratory of Crop Genetics and Germplasm Enhancement, Key Laboratory of Plant Nutrition and Fertilization in Low-Middle Reaches of the Yangtze River, Ministry of Agriculture, Nanjing Agricultural University, Nanjing 210095, China. Electronic address:

High nitrogen (N) fertilization for maximizing crop yield commonly leads to postponed flowering time (heading date in rice) and ripening, thus affecting resources use efficiency and followed planting time. We found that N-mediated heading date-1 (Nhd1) can directly activate florigen gene OsHd3a in rice. Inactivation of either Nhd1 or OsHd3a results in delay and insensitivity to N supply of flowering time. Knockout of Nhd1 increases N uptake and utilization efficiency at low-to-moderate N level under both short- and long-day field conditions. Increasing glutamine, the product of N assimilation, can upregulate expression of Nhd1, which in turn downregulates OsFd-GOGAT expression and OsFd-GOGAT activity, displaying a Nhd1-controlled negative feedback regulatory pathway of N assimilation. Moreover, N fertilization effect on rice flowering time shows genetically controlled diversity, and single-nucleotide polymorphism in Nhd1 promoter may relate to different responses of flowering time to N application. Nhd1 thus balances flowering time and N use efficiency in addition to photoperiod in rice.
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http://dx.doi.org/10.1016/j.cub.2020.10.095DOI Listing
February 2021

Two ADP-glucose pyrophosphorylase subunits, OsAGPL1 and OsAGPS1, modulate phosphorus homeostasis in rice.

Plant J 2020 12 6;104(5):1269-1284. Epub 2020 Nov 6.

State Key Laboratory of Crop Genetics and Germplasm Enhancement, Nanjing Agricultural University, Nanjing, 210095, China.

Plant acclimatory responses to phosphate (Pi) starvation stress include the accumulation of carbohydrates, namely sugar and starch. However, whether altered endogenous carbohydrate profile could in turn affect plant Pi starvation responses remains widely unexplored. Here, two genes encoding the large and small subunits of an ADP-glucose pyrophosphorylase (AGP) in rice (Oryza sativa), AGP Large Subunit 1 (AGPL1) and AGP Small Subunit 1 (AGPS1), were functionally characterized with regard to maintenance of phosphorus (P) homeostasis and regulation of Pi starvation signaling. AGPL1 and AGPS1 were both positively responsive to nitrogen (N) or Pi deprivation, and expressed in almost all the tissues except in the meristem and mature zones of root. AGPL1 and AGPS1 physically interacted in chloroplast, and catalyzed the rate-limiting step of starch biosynthesis. Low-N- (LN) and low-Pi (LP)-triggered starch accumulation in leaves was impaired in agpl1, agps1 and apgl1 agps1 mutants compared with the wild-type plants. By contrast, mutation of AGPL1 and/or AGPS1 led to an increase in the content of the major sugar, sucrose, in leaf sheath and root under control and LN conditions. Moreover, the Pi accumulation was enhanced in the mutants under control and LN conditions, but not LP conditions. Notably, the LN-induced suppression of Pi accumulation was compromised attributed to the mutation of AGPL1 and/or AGPS1. Furthermore, the increased Pi accumulation was accompanied by the specific suppression of OsSPX2 and activation of several Pi transporter genes. These results indicate that a balanced level of carbohydrates is vital for maintaining plant P homeostasis.
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http://dx.doi.org/10.1111/tpj.14998DOI Listing
December 2020

UV-irradiation induced biological activity and antibacterial activity of ZnO coated magnesium alloy.

Mater Sci Eng C Mater Biol Appl 2020 Sep 5;114:110997. Epub 2020 May 5.

Department of Orthopedic Surgery, Changzheng Hospital, Second Military Medical University, Shanghai 200003, China. Electronic address:

In order to improve the biological activity and antibacterial activity of magnesium alloy, the single zinc oxide (ZnO) coating was prepared on magnesium alloys using microwave aqueous synthesis method and followed heat treatment. Then, the coated magnesium alloys were irradiated with ultraviolet (UV) light for different time and subsequently immersed in simulated body fluids (SBF). The influences of UV-irradiated time on the morphology, composition, in vitro biological activity and antibacterial activity were investigated. The results indicated that the ability of the apatite formation on the ZnO coated magnesium alloys surface was significantly enhanced as UV irradiation time prolonged, and the bone-like apatite was formed after UV irradiation for 24 h and then immersing into SBF for 2 weeks, the newly formed apatite was dense and integrate, implying that UV irradiation could activate ZnO coating to improve the biological activity. Moreover, after immersing in SBF for 2 weeks, the antibacterial experiment results demonstrated that ZnO coated magnesium alloys with UV irradiation time of 24 h exhibited more effective antibacterial activity than those of naked magnesium alloys and ZnO coated magnesium alloys which were not irradiated by ultraviolet (UV) light. This work afforded a surface strategy for designing magnesium alloy implant with desirable osseointegration ability and antibacterial property simultaneously for orthopedic and dental applications.
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http://dx.doi.org/10.1016/j.msec.2020.110997DOI Listing
September 2020

Near-infrared light-triggered NO release for spinal cord injury repair.

Sci Adv 2020 Sep 25;6(39). Epub 2020 Sep 25.

Shanghai Key Laboratory of Green Chemistry and Chemical Processes, School of Chemistry and Molecular Engineering, East China Normal University, Shanghai 200062, P. R. China.

Traumatic spinal cord injury (SCI) is caused by external physical impacts and can induce complex cascade events, sometimes converging to paralysis. Existing clinical drugs to traumatic SCI have limited therapeutic efficacy because of either the poor blood-spinal cord barrier (BSCB) permeability or a single function. Here, we suggest a "pleiotropic messenger" strategy based on near-infrared (NIR)-triggered on-demand NO release at the lesion area for traumatic SCI recovery via the concurrent neuroregeneration and neuroprotection processing. This NO delivery system was constructed as upconversion nanoparticle (UCNP) core coated by zeolitic imidazolate framework-8 (ZIF-8) with NO donor (CysNO). This combined strategy substantial promotes the repair of SCI in vertebrates, ascribable to the pleiotropic effects of NO including the suppression of gliosis and inflammation, the promotion of neuroregeneration, and the protection of neurons from apoptosis, which opens intriguing perspectives not only in nerve repair but also in neurological research and tissue engineering.
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http://dx.doi.org/10.1126/sciadv.abc3513DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7518874PMC
September 2020

OsWRKY21 and OsWRKY108 function redundantly to promote phosphate accumulation through maintaining the constitutive expression of OsPHT1;1 under phosphate-replete conditions.

New Phytol 2021 02 10;229(3):1598-1614. Epub 2020 Oct 10.

State Key Laboratory of Crop Genetics and Germplasm Enhancement, Nanjing Agricultural University, Nanjing, 210095, China.

Plant Phosphate Transporter 1 (PHT1) proteins, probably the only influx transporters for phosphate (Pi) uptake, are partially degraded on sufficient Pi levels to prevent excessive Pi accumulation. Therefore, the basal/constitutive expression level of PHT1 genes is vital for maintaining Pi uptake under Pi-replete conditions. Rice (Oryza sativa) OsPHT1;1 is a unique gene as it is highly expressed and not responsive to Pi, however the mechanism for maintaining its basal/constitutive expression remains unknown. Using biochemical and genetic approaches, we identified and functionally characterised the transcription factors maintaining the basal/constitutive expression of OsPHT1;1. OsWRKY21 and OsWRKY108 interact within the nucleus and both bind to the W-box in the OsPHT1;1 promoter. Overexpression of OsWRKY21 or OsWRKY108 led to increased Pi accumulation, resulting from elevated expression of OsPHT1;1. By contrast, oswrky21 oswrky108 double mutants showed decreased Pi accumulation and OsPHT1;1 expression in a Pi-dependent manner. Moreover, similar to ospht1;1 mutants, plants expressing the OsWRKY21-SRDX fusion protein (a chimeric dominant suppressor) were impaired in Pi accumulation in Pi-replete roots, accompanied by downregulation of OsPHT1;1 expression. Our findings demonstrated that rice WRKY transcription factors function redundantly to promote Pi uptake by activating OsPHT1;1 expression under Pi-replete conditions, and represent a novel pathway independent of the central Pi signalling system.
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http://dx.doi.org/10.1111/nph.16931DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7820984PMC
February 2021

Co-Overexpression of and Increased Agronomic Nitrogen Use Efficiency in Transgenic Rice Plants.

Front Plant Sci 2020 12;11:1245. Epub 2020 Aug 12.

State Key Laboratory of Crop Genetics and Germplasm Enhancement, MOA Key Laboratory of Plant Nutrition and Fertilization in Low-Middle Reaches of the Yangtze River, Nanjing Agricultural University, Nanjing, China.

The NO transporter plays an important role in rice nitrogen acquisition and nitrogen-use efficiency. Our previous studies have shown that the high affinity systems for nitrate uptake in rice is mediated by a two-component NRT2/NAR2 transport system. In this study, transgenic plants were successful developed by overexpression of alone, alone and co-overexpression of and . Our field experiments indicated that transgenic lines expressing or constructs exhibited increased grain yields of approximately 14.1% and 24.6% compared with wild-type (cv. Wuyunjing 7, WT) plants, and the agricultural nitrogen use efficiency increased by 15.8% and 28.6%, respectively. Compared with WT, the N influx in roots of and lines increased 18.9%‑27.8% in response to 0.2 mM, 2.5 mM NO , and 1.25 mM NH NO, while there was no significant difference between and lines; only the N distribution ratio of shoot to root for lines increased significantly. However, there were no significant differences in nitrogen use efficiency, N influx in roots and the yield between the transgenic lines and WT. This study indicated that co-overexpression of and could increase rice yield and nitrogen use efficiency.
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http://dx.doi.org/10.3389/fpls.2020.01245DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7434940PMC
August 2020

Rice plants respond to ammonium stress by adopting a helical root growth pattern.

Plant J 2020 11 22;104(4):1023-1037. Epub 2020 Sep 22.

State Key Laboratory of Crop Genetics and Germplasm Enhancement and MOA Key Laboratory of Plant Nutrition and Fertilization in Lower-Middle Reaches of the Yangtze River, Nanjing Agricultural University, Nanjing, 210095, China.

High levels of ammonium nutrition reduce plant growth and different plant species have developed distinct strategies to maximize ammonium acquisition while alleviating ammonium toxicity through modulating root growth. To date, the mechanisms underlying plant tolerance or sensitivity towards ammonium remain unclear. Rice (Oryza sativa) uses ammonium as its main N source. Here we show that ammonium supply restricts rice root elongation and induces a helical growth pattern, which is attributed to root acidification resulting from ammonium uptake. Ammonium-induced low pH triggers the asymmetric distribution of auxin in rice root tips through changes in auxin signaling, thereby inducing a helical growth response. Blocking auxin signaling completely inhibited this root response. In contrast, this root response is not activated in ammonium-treated Arabidopsis. Acidification of Arabidopsis roots leads to the protonation of indole-3-acetic acid and dampening of the intracellular auxin signaling levels that are required for maintaining root growth. Our study suggests a different mode of action by ammonium on the root pattern and auxin response machinery in rice versus Arabidopsis, and the rice-specific helical root response towards ammonium is an expression of the ability of rice to moderate auxin signaling and root growth to utilize ammonium while confronting acidic stress.
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http://dx.doi.org/10.1111/tpj.14978DOI Listing
November 2020

OsPIN9, an auxin efflux carrier, is required for the regulation of rice tiller bud outgrowth by ammonium.

New Phytol 2021 01 24;229(2):935-949. Epub 2020 Oct 24.

State Key Laboratory of Crop Genetics and Germplasm Enhancement, Key Laboratory of Plant Nutrition and Fertilization in Low-Middle Reaches of the Yangtze River, Ministry of Agriculture, Nanjing Agricultural University, Nanjing, 210095, China.

The degree of rice tillering is an important agronomic trait that can be markedly affected by nitrogen supply. However, less is known about how nitrogen-regulated rice tillering is related to polar auxin transport. Compared with nitrate, ammonium induced tiller development and was paralleled with increased H-indole-acetic acid (IAA) transport and greater auxin into the junctions. OsPIN9, an auxin efflux carrier, was selected as the candidate gene involved in ammonium-regulated tillering based on GeneChip data. Compared with wild-type plants, ospin9 mutants had fewer tillers, and OsPIN9 overexpression increased the tiller number. Additionally, OsPIN9 was mainly expressed in vascular tissue of the junction and tiller buds, and encoded a membrane-localised protein. Heterologous expression in Xenopus oocytes and yeast demonstrated that OsPIN9 is a functional auxin efflux transporter. More importantly, its RNA and protein levels were induced by ammonium but not by nitrate, and tiller numbers in mutants did not respond to nitrogen forms. Further advantages, including increased tiller number and grain yield, were observed in overexpression lines grown in the paddy field at a low-nitrogen rate compared with at a high-nitrogen rate. Our data revealed that ammonium supply and an auxin efflux transporter co-ordinately control tiller bud elongation in rice.
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http://dx.doi.org/10.1111/nph.16901DOI Listing
January 2021

Rice OsLHT1 Functions in Leaf-to-Panicle Nitrogen Allocation for Grain Yield and Quality.

Front Plant Sci 2020 29;11:1150. Epub 2020 Jul 29.

State Key Laboratory of Crop Genetics and Germplasm Enhancement, MOA Key Laboratory of Plant Nutrition and Fertilization in Lower-Middle Reaches of the Yangtze River, Nanjing Agricultural University, Nanjing, China.

Proper allocation of nitrogen (N) from source leaves to grains is essential step for high crop grain yield and N use efficiency. In rice () grown in flooding paddy field, amino acids are the major N compounds for N distribution and re-allocation. We have recently identified that () is the major transporter for root uptake and root-to-shoot allocation of amino acids in rice. In this study, we planted knockout mutant lines of together wild-type (WT) in paddy field for evaluating OsLHT1 function in N redistribution and grain production. OsLHT1 is expressed in vascular bundles of leaves, rachis, and flowering organs. plants showed lower panicle length and seed setting rate, especially lower grain number per panicle and total grain weight. The concentrations of both total N and free amino acids in the flag leaf were similar at anthesis between lines and WT while significantly higher in the mutants than WT at maturation. The seeds contained higher proteins and most of the essential free amino acids, similar total starch but less amylose with lower paste viscosity than WT seeds. The mutant seeds showed lower germination rate than WT. Knockout of decreased N uptake efficiency and physiological utilization efficiency (kg-grains/kg-N) by about 55% and 72%, respectively. Taken together, we conclude that OsLHT1 plays critical role in the translocation of amino acids from vegetative to reproductive organs for grain yield and quality of nutrition and functionality.
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http://dx.doi.org/10.3389/fpls.2020.01150DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7403224PMC
July 2020

Improving nitrogen use efficiency: from cells to plant systems.

J Exp Bot 2020 07;71(15):4359-4364

Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, USA.

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http://dx.doi.org/10.1093/jxb/eraa309DOI Listing
July 2020
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