Photoperiod and gravistimulation-associated Tiller Angle Control 1 modulates dynamic changes in rice plant architecture.

KEY MESSAGE: TAC1 is involved in photoperiodic and gravitropic responses to modulate rice dynamic plant architecture likely by affecting endogenous auxin distribution, which could explain TAC1 widespread distribution in indica rice. Plants experience a changing environment throughout their growth, which requires dynamic adjustments of plant architecture in response to these environmental cues. Our previous study demonstrated that Tiller Angle Control 1 (TAC1) modulates dynamic changes in plant architecture in rice; however, the underlying regulatory mechanisms remain largely unknown. In this study, we show that TAC1 regulates plant architecture in an expression dose-dependent manner, is highly expressed in stems, and exhibits dynamic expression in tiller bases during the growth period. Photoperiodic treatments revealed that TAC1 expression shows circadian rhythm and is more abundant during the dark period than during the light period and under short-day conditions than under long-day conditions. Therefore, it contributes to dynamic plant architecture under long-day conditions and loose plant architecture under short-day conditions. Gravity treatments showed that TAC1 is induced by gravistimulation and negatively regulates shoot gravitropism, likely by affecting auxin distribution. Notably, the tested indica rice containing TAC1 displayed dynamic plant architecture under natural long-day conditions, likely explaining the widespread distribution of TAC1 in indica rice. Our results provide new insights into TAC1-mediated regulatory mechanisms for dynamic changes in rice plant architecture.

Tiller Angle Control 1 Is Essential for the Dynamic Changes in Plant Architecture in Rice.

Plant architecture is dynamic as plants develop. Although many genes associated with specific plant architecture components have been identified in rice, genes related to underlying dynamic changes in plant architecture remain largely unknown. Here, we identified two highly similar recombinant inbred lines (RILs) with different plant architecture: RIL-Dynamic (D) and RIL-Compact (C). The dynamic plant architecture of RIL-D is characterized by 'loosetiller angle (tillering stage)-compact (heading stage)-loosecurved stem (maturing stage)' under natural long-day (NLD) conditions, and 'loosetiller angle (tillering and heading stages)-loosetiller angle and curved stem (maturing stage)' under natural short-day (NSD) conditions, while RIL-C exhibits a compact plant architecture both under NLD and NSD conditions throughout growth. The candidate locus was mapped to the chromosome 9 tail via the rice 8K chip assay and map-based cloning. Sequencing, complementary tests, and gene knockout tests demonstrated that Tiller Angle Control 1 (TAC1) is responsible for dynamic plant architecture in RIL-D. Moreover, TAC1 positively regulates loose plant architecture, and high TAC1 expression cannot influence the expression of tested tiller-angle-related genes. Our results reveal that TAC1 is necessary for the dynamic changes in plant architecture, which can guide improvements in plant architecture during the modern super rice breeding.

UBIAD1 protects against oxygen-glucose deprivation/reoxygenation injury via nNOS/NO pathway. / UBIAD1通过抑制nNOS/NO途径减轻氧糖剥夺再灌注损伤.

OBJECTIVES: Cerebral infarction is a subtype of stroke with high incidence and disability rate. Ischemia reperfusion injury (IRI) is the key point of cerebral infarction treatment. UbiA prenyltransferase domain containing 1 (UBIAD1) is a kind of enzyme with various biological functions including electron transport in mitochondrial respiratory chain, lipid metabolism, and oxidative stress which are related to IRI. The purpose of this study aims to determine the neuroprotective effects and the underlying mechanisms of UBIAD1 in cerebral IRI. METHODS: We employed oxygen-glucose deprivation/reoxygenation (OGD/R) model in mouse neuroblastoma Neuro2a (N2a) cells to mimic cerebral IRI. Lentivirus vector over-expressed UBIAD1 was transfacted into N2a cells to maintain high and stable expression of UBIAD1. In the first part of the experiment, N2a cells were divided into 5 groups: A non-OGD (N2a cells without exposure to OGD) group, groups of reoxygenation 0, 4, 12 and 24 h after 4 h of OGD, respectively. In the second part of the experiment, N2a cells were divided into 6 groups: A Con (normal cell)+non-OGD group, an EV (cell transfected with empty vector)+non-OGD group, an OE (over-expressed UBIAD1)+non-OGD group, a Con+OGD/R group, an EV+OGD/R group, and an OE+OGD/R group. In the third part, the N2a cells were divided into 8 groups: A Con+non-OGD group, an OE+non-OGD group, a Con+non-OGD+nNOS inhibitior 7-nitroindazole (7-NI) group, an OE+non-OGD+7-NI group, a Con+OGD/R group, an OE+OGD/R group, a Con+OGD/R+7-NI group, and an OE+OGD/R+7-NI group. The morphological changes of Golgi apparatus were observed under the confocal laser scanning microscope. The mRNA and protein levels of UBIAD1, secretory pathway Ca2+-ATPase isoform 1 (SPCA1), and NOS were determined by real-time PCR and Western blotting, respectively. Cell apoptosis rate was detected with flow cytometry; cell viability was detected with MTT assay, and NO release was determined with Griess assay. RESULTS: Compared with the non-OGD group, the expression levels of UBIAD1 mRNA and protein in N2a cells in the groups of 0, 4, 12 and 24 h reoxygenation after OGD 4 h decreased significantly (P<0.05 or P<0.01), and the longer the reoxygenation time, the more significant the reduction of UBIAD1 expression. Compared with the Con+OGD/R group and the EV+OGD/R group, mRNA and protein levels of UBIAD1 and SPCA1 were increased (P<0.05 or P<0.01), the apoptosis rate was decreased (all P<0.01), and the cell viability was increased (all P<0.01) in the OE+OGD/R group. The Golgi fragmentation was less in the OE+OGD/R group than that in the Con+ OGD/R group and the EV+OGD/R group. The mRNA and protein levels of endothelial NOS (eNOS) and neuronal NOS (nNOS) were decreased (P<0.05 or P<0.01), and the level of NO was decreased (all P<0.01) in the groups over-expressed UBIAD1 (OE+non-OGD group vs Con+non-OGD group, OE+OGD/R group vs Con+OGD/R group). The level of NO and apoptosis rate of N2a cells were decreased (all P<0.01) in the the groups pretreated with 7-NI (Con+OGD/R+7-NI group vs Con+OGD/R group, OE+OGD/R+7-NI group vs OE+OGD/R group). CONCLUSIONS: UBIAD1 may exerts protective effects on OGD/R induced N2a cells by ameliorating Golgi apparatus dysfunction via the nNOS/NO pathway.

Identification of 4 immune cells and a 5-lncRNA risk signature with prognosis for early-stage lung adenocarcinoma.

BACKGROUND: Lung cancer is the most common cancer and cause of cancer-related mortality worldwide, increasing evidence indicated that there was a significant correlation between tumors and the long non-coding RNAs (lncRNAs), as well as tumor immune infiltration, but their role in early lung adenocarcinoma (LUAD) are still unclear. METHODS: Gene expression data and corresponding clinical data of early-stage LUAD patients were downloaded from GEO and TCGA databases. 24 kinds of tumor-infiltrating immune cells were analyzed by quantity analysis and univariate cox regression analysis, we divided patients into two subgroups using consensus clustering, recognized the differentially expressed genes (DEGs) in the subgroups, then, established lncRNA risk signature by least absolute shrinkage and selection operator (LASSO) regression. RESULTS: A total of 718 patients were enrolled in this study, including 246 from GSE31210 dataset, 127 from GSE50081 dataset and 345 from TCGA-LUAD. We identified that Th2 cells, TFH, NK CD56dim cells and Mast cells were prognosis-related(p < 0.05), then established a 5-lncRNA risk signature (risk score = 0.374600616* LINC00857 + 0.173825706* LINC01116 + (- 0.021398903)* DRAIC + (- 0.113658256)* LINC01140 + (- 0.008403702)* XIST), and draw a nomogram showed that the signature had a well prediction accuracy and discrimination. CONCLUSIONS: We identified 4 immune infiltrating cells related to the prognosis of early-stage LUAD, and established a novel 5 immune-related lncRNA signature for predicting patients' prognosis.

Reduction of OsMPK6 activity by a R89K mutation induces cell death and bacterial blight resistance in rice.

KEY MESSAGE: The R89 is essential for the kinase activity of OsMPK6 which negatively regulates cell death and defense response in rice. Mitogen-activated protein kinase cascade plays critical roles in various vital activities, including the plant immune response, but the mechanisms remain elusive. Here, we identified and characterized a rice lesion mimic mutant osmpk6 which displayed hypersensitive response-like lesions in company with cell death and hydrogen peroxide hyperaccumulation. Map-based cloning and complementation demonstrated that a G702A single-base substitution in the second exon of OsMPK6 led to the lesion mimic phenotype of the osmpk6 mutant. OsMPK6 encodes a cytoplasm and nucleus-targeted mitogen-activated protein kinase and is expressed in the various organs. Compared with wild type, the osmpk6 mutant exhibited high resistance to the bacterial pathogen Xanthomonas oryzae pv. oryzae (Xoo), likely due to the increased ROS production induced by flg22 and chitin and up-regulated expression of genes involved in pathogenesis, as well as activation of SA and JA signaling pathways after inoculation. By contrast, the OsMPK6-overexpression line (OE-1) was found to be susceptible to the bacterial pathogens, indicating that OsMPK6 negatively regulated Xoo resistance. Furthermore, the G702A single-base substitution caused a R89K mutation at both polypeptide substrate-binding site and active site of OsMPK6, and kinase activity assay revealed that the R89K mutation led to reduction of OsMPK6 activity, suggesting that the R89 is essential for the function of OsMPK6. Our findings provide insight into a vital role of the R89 of OsMPK6 in regulating cell death and defense response in rice.

WB1, a Regulator of Endosperm Development in Rice, Is Identified by a Modified MutMap Method.

Abnormally developed endosperm strongly affects rice (Oryza sativa) appearance quality and grain weight. Endosperm formation is a complex process, and although many enzymes and related regulators have been identified, many other related factors remain largely unknown. Here, we report the isolation and characterization of a recessive mutation of White Belly 1 (WB1), which regulates rice endosperm development, using a modified MutMap method in the rice mutant wb1. The wb1 mutant develops a white-belly endosperm and abnormal starch granules in the inner portion of white grains. Representative of the white-belly phenotype, grains of wb1 showed a higher grain chalkiness rate and degree and a lower 1000-grain weight (decreased by ~34%), in comparison with that of Wild Type (WT). The contents of amylose and amylopectin in wb1 significantly decreased, and its physical properties were also altered. We adopted the modified MutMap method to identify 2.52 Mb candidate regions with a high specificity, where we detected 275 SNPs in chromosome 4. Finally, we identified 19 SNPs at 12 candidate genes. Transcript levels analysis of all candidate genes showed that WB1 (Os04t0413500), encoding a cell-wall invertase, was the most probable cause of white-belly endosperm phenotype. Switching off WB1 with the CRISPR/cas9 system in Japonica cv. Nipponbare demonstrates that WB1 regulates endosperm development and that different mutations of WB1 disrupt its biological function. All of these results taken together suggest that the wb1 mutant is controlled by the mutation of WB1, and that the modified MutMap method is feasible to identify mutant genes, and could promote genetic improvement in rice.

Dural arteriovenous fistula and sinus thrombosis presenting as parkinsonism and dementia: a case report with literature review.

Introduction: Dural arteriovenous fistula (DAVF) is an uncommon malformation involving an abnormal connection between dural arteries, or the pachymeningeal branches of cerebral arteries, and dural veins. Its exact pathogenesis remains elusive. Known potential triggers for DAVF include cerebral venous sinus thrombosis (CVST), trauma, ear infections, and cranial surgeries. Due to its rarity and diverse clinical presentations, diagnosing DAVF can be a challenge. Case description: We present a case of DAVF associated with CVST, manifesting as rapidly advancing parkinsonism accompanied by dementia over a month. Brain magnetic resonance imaging (MRI) revealed bilateral symmetric T2 hyperintensities in the basal ganglia and brain stem. Cerebral angiography further confirmed a fistula between the torcular herophili and the transverse-sigmoid sinuses. Despite strong recommendations for transvenous embolization of the fistula, the patient declined the procedure. The anticoagulant therapy and symptomatic treatments administered did not yield any improvement in the patient's condition. Additionally, we reviewed 27 DAVF-derived parkinsonism and dementia cases. Conclusion: DAVF must be considered in the differential diagnosis of cases of rapidly progressive parkinsonism with concurrent dementia. Given its potential for treatment and reversibility, timely diagnosis and intervention for DAVF are paramount.

Case Report: Unusual Varicella-Zoster Virus Meningoencephalitis With Meningomyelitis Mimicking Central Nervous System Leukemia.

Background: Varicella-Zoster Virus (VZV) is a human pathogen from the α-subfamily of herpesviruses. In immunocompromised patients, VZV may produce disease of the central nervous system (CNS). Clinical manifestations of CNS infection with VZV are non-specific and can mimic other infectious and non-infectious diseases. Due to similar symptoms, CNS infection with VZV represents a diagnostic challenge. Here, we report a case of a patient who showed laboratory and imaging manifestations mimicking the neoplastic etiology. Case: A 31-year-old man presented with a 3-day history of headache, 5-h of confusion, generalized tonic-clonic seizures, and transient fever. The patient has a history of acute myelogenous leukemia (AML). His cerebrospinal fluid (CSF) studies revealed markedly elevated protein (10.326 g/L) and atypical cells. Meanwhile, the MRI of brain, cervical, and thoracic spine was reported as extensive (frontal, parieto-occipital and temporal pachymeningeal, and falx cerebri) enhancement and irregular thickening. These examinations suggested a suspicion of CNS involvement of AML. However, based on further investigations with metagenomic next-generation sequencing, a final diagnosis of VZV meningoencephalitis with meningomyelitis was made. With acyclovir and foscarnet sodium therapy, repeated CSF studies revealed normal cell count and protein. No atypical cells were found. The repeated brain MRI also revealed obvious resolution of the previous abnormal pachymeningeal enhancement. Conclusion: This case highlights the importance of recognizing the unusual phenomenon of traditional tests in VZV meningoencephalitis with meningomyelitis, and timely using of further precise examinations to detect viral DNA, which is required to prevent missed diagnosis.

STRIPE3, encoding a human dNTPase SAMHD1 homolog, regulates chloroplast development in rice.

Chloroplast is an important organelle for photosynthesis and numerous essential metabolic processes, thus ensuring plant fitness or survival. Although many genes involved in chloroplast development have been identified, mechanisms underlying such development are not fully understood. Here, we isolated and characterized the stripe3 (st3) mutant which exhibited white-striped leaves with reduced chlorophyll content and abnormal chloroplast development during the seedling stage, but gradually produced nearly normal green leaves as it developed. Map-based cloning and transgenic tests demonstrated that a splicing mutation in ST3, encoding a human deoxynucleoside triphosphate triphosphohydrolase (dNTPase) SAMHD1 homolog, was responsible for st3 phenotypes. ST3 is highly expressed in the third leaf at three-leaf stage and expressed constitutively in root, stem, leaf, sheath, and panicle, and the encoded protein, OsSAMHD1, is localized to the cytoplasm. The st3 mutant showed more severe albino leaf phenotype under exogenous 1-mM dATP/dA, dCTP/dC, and dGTP/dG treatments compared with the control conditions, indicating that ST3 is involved in dNTP metabolism. This study reveals a gene associated with dNTP catabolism, and propose a model in which chloroplast development in rice is regulated by the dNTP pool, providing a potential application of these results to hybrid rice breeding.

Relationship Between Pregnancy and Acute Disseminated Encephalomyelitis: A Single-Case Study.

The relationship between pregnancy and autoimmune diseases is unclear. This study investigated the possible role of local immune changes and the activation state of the HMGB1/TLR4/Nf-κB/IL-6 pathway at the maternal-fetal interface during pregnancy in the pathogenesis of acute disseminated encephalomyelitis (ADEM). Clinical data and blood samples of a patient with ADEM were collected to observe the dynamic changes in lymphocyte populations after an abortion. The expression of HMGB1, TLR4, Nf-κB, AQP4, IL-2, IL-4, IL-6, and TNF-α in the fetal membrane and placenta was compared between the patient with pregnancy-related ADEM and a woman with a normal pregnancy using Real-time qPCR and western blotting (WB). The patient was diagnosed with ADEM in the early stage of pregnancy after showing limb weakness symptoms. In the third month of gestation, the symptoms worsened, with a disturbance of consciousness and breathing. After the abortion, the patient relapsed with vertigo and visual rotation. Analysis of lymphocyte subsets by flow cytometry showed that B lymphocytes increased, while natural killer T lymphocytes decreased. WB and Real-time qPCR showed that the expression levels of HMGB1, TLR4, Nf-κB, AQP4, and IL-6 in the fetal membrane and placenta were higher in the patient with pregnancy-related ADEM than in the woman with a normal pregnancy, while those of IL-2 were lower in the patient than in the woman with a normal pregnancy. The local immune changes and the activation of the HMGB1/TLR4/Nf-κB/IL-6 pathway at the maternal-fetal interface may be related to the pathogenesis of ADEM.

Characterization and genetic analysis of the oshpl3 rice lesion mimic mutant showing spontaneous cell death and enhanced bacterial blight resistance.

Plant lesion mimic mutants have been used as ideal materials for studying pathogen defense mechanisms due to their spontaneous activation of defense responses in plants. Here, we report the identification and characterization of a rice lesion mimic mutant, oshpl3. The oshpl3 mutant initially displayed white spots on leaves of 7-day-old seedlings, and the white spots gradually turned into large brown spots during plant development, accompanied by poor metrics of major agronomic traits. Histochemical analysis showed that spontaneous cell death and H2O2 hyperaccumulation occurred in oshpl3. Defense responses were induced in the oshpl3 mutant, such as enhanced ROS signaling activated by recognition of pathogen-associated molecular patterns, and also upregulated expression of genes involved in pathogenesis and JA metabolism. These defense responses enhanced resistance to bacterial blight caused by Xanthomonas oryzae pv. oryzae. The mutated gene was identified as OsHPL3 (LOC_Os02g02000) by map-based cloning. A G1006A mutation occurred in OsHPL3, causing a G-to-D mutation of the 295th amino acid in the transmembrane region of OsHPL3. OsHPL3 localized to the chloroplast, cytoplasm, and another unknown organelle, while the mutated protein OsHPL3G295D was not obviously observed in the chloroplast, suggesting that the G295D mutation affected its chloroplast localization. Based on our findings, the G295D mutation in OsHPL3 is most likely responsible for the phenotypes of the oshpl3 mutant. Our results provide new clues for studying the function of the OsHPL3 protein.

Soluble epoxide hydrolase inhibition decreases reperfusion injury after focal cerebral ischemia.

Epoxyeicosatrienoic acids (EETs) are produced by cytochrome P450 epoxygenases from arachidonic acid, and their rapid metabolism is mainly through soluble epoxide hydrolase (sEH). EETs exert vasodilatory, anti-inflammatory, anti-apoptotic, and pro-angiogenic effects. Administration of sEH inhibitors before or at the onset of stroke is protective, but the effects of post-treatment at reperfusion, when inflammation is augmented, has not been as well studied. We tested the hypothesis that 1-Trifluoromethoxyphenyl-3-(1-propionylpiperidin-4-yl)urea (TPPU), a potent and highly selective sEH inhibitor, suppresses inflammation and protects the brain when administered at reperfusion. Vehicle or 1 mg/kg TPPU was administered at reperfusion after 90 minutes of focal ischemia and again 24 hours later. Protein expression and activity of sEH increased after reperfusion and activity was decreased by TPPU administration. TPPU decreased infarct volume by 50%, reduced neurologic deficits and improved performance on sensorimotor tasks. Furthermore, TPPU significantly lowered the mRNA expression of interleukin-1beta by 3.5-fold and tumor necrosis factor-alpha by 2.2-fold, increased transforming growth factor-beta mRNA by 1.8-fold, and augmented immunostaining of vascular endothelial growth factor in peri-infarct cortex. Thus, inhibition of sEH at reperfusion significantly reduces infarction and improves sensorimotor function, possibly by suppressing early proinflammatory cytokines and promoting reparative cytokines and growth factors.

Inhibition of sphingomyelin synthase 1 affects ceramide accumulation and hydrogen peroxide-induced apoptosis in Neuro-2a cells.

Oxidative stress plays a key role in brain injury after cerebral ischemia-reperfusion, which contributes toward excessive apoptosis of nerve cells. Therefore, it would be beneficial to identify a therapy that could interfere with the progression of apoptosis and protect the brain from ischemia-reperfusion injury. As ceramide, a well-known second messenger of apoptosis, can be metabolized by sphingomyelin synthase 1 (SMS1), recent research has focused on the link between SMS1 and apoptosis in different cells. To investigate whether SMS1 is involved in the process of oxidative stress-induced apoptosis in neurons and to explore the possible underlying mechanism, we treated mouse neuroblastoma Neuro-2A (N2a) cells with hydrogen peroxide (H2O2). Incubation with H2O2 significantly upregulated the expression of SMS1, increased the intracellular levels of ceramide and sphingomyelin synthase activity, and induced apoptosis. Moreover, pretreatment of N2a cells with D609, an sphingomyelin synthase inhibitor, or SMS1-silencing RNA (siRNA) further increased ceramide and potentiated H2O2-induced apoptosis which could be reversed by SB203580 (a p38 inhibitor). Thus, our study has shown that SMS1 regulates ceramide levels in N2a cells and plays a potent protective role in this oxidative stress-induced apoptosis partly through the p38 pathway.

Study of GOLPH3: a potential stress-inducible protein from Golgi apparatus.

Although the Golgi apparatus has been studied extensively for over 100 years, the complex structure-function relationships have yet to be elucidated. It is well known that the Golgi complex plays an important role in the transport, processing, sorting, and targeting of numerous proteins and lipids destined for secretion, plasma membrane, and lysosomes. Increasing evidence suggests that the Golgi apparatus is a sensor and common downstream effector of stress signals in cell death pathways. It undergoes disassembly and fragmentation in several neurological disorders. Recent studies indicate that Golgi phosphoprotein 3 (GOLPH3 also known as GPP34/GMx33/MIDAS), a peripheral membrane protein of trans-Golgi network, represents an exciting new class of oncoproteins involved in cell signal transduction and is potentially mobilized by stress. In this review, we focus on the importance of GOLPH3 in vesicular trafficking, Golgi architecture maintenance, receptor sorting, protein glycosylation, and further discuss its potential in signal sensing in stress response.

Morphology of platelet Golgi apparatus and their significance after acute cerebral infarction.

Blood samples were harvested from the antecubital vein of 20 fasting patients with acute cerebral infarction at 1, 7 and 15 days after onset to prepare blood platelet suspension. Fasting antecubital vein blood was collected from an additional 20 normal adults as controls. Under transmission tron microscope, platelet Golgi tubules and vesicles became significantly thickened, enlarged, and irregular after acute cerebral infarction. Alpha granules in platelets significantly reduced in number, especially 1 day after cerebral infarction. Under immunoelectron microscopy, a few alpha granules aggregated around Golgi tubules and vesicles after infarction. These results suggested that platelet Golgi apparatus displayed significant morphological changes, which were possibly associated with enhanced synthetic and secretory functions of activated platelets after acute cerebral infarction. This study used Golgi apparatus blocking agent Brefeldin A to block Golgi apparatus in an aim to study the effects of Golgi apparatus on CD40L expression on the surface of activated platelets. Flow cytometry revealed that CD40L expression on activated platelet surfaces decreased significantly when Golgi apparatus was blocked, which indicated that Golgi apparatus participated in the synthesis and transport of CD40L to the platelet surface.