OsLCD3 interacts with OsSAMS1 to regulate grain size via ethylene/polyamine homeostasis control.

A fundamental question in developmental biology is how to regulate grain size to improve crop yields. Despite this, little is still known about the genetics and molecular mechanisms regulating grain size in crops. Here, we provide evidence that a putative protein kinase-like (OsLCD3) interacts with the S-adenosyl-L-methionine synthetase 1 (OsSAMS1) and determines the size and weight of grains. OsLCD3 mutation (lcd3) significantly increased grain size and weight by promoting cell expansion in spikelet hull, whereas its overexpression caused negative effects, suggesting that grain size was negatively regulated by OsLCD3. Importantly, lcd3 and OsSAMS1 overexpression (SAM1OE) led to large and heavy grains, with increased ethylene and decreased polyamines production. Based on genetic analyses, it appears that OsLCD3 and OsSAMS1 control rice grain size in part by ethylene/polyamine homeostasis. The results of this study provide a genetic and molecular understanding of how the OsLCD3-OsSAMS1 regulatory module regulates grain size, suggesting that ethylene/polyamine homeostasis is an appropriate target for improving grain size and weight.

RNA modification-related EIF4G2 is an immunotherapy determinant in osteosarcoma: A single-cell sequencing analysis.

The clinical outcomes of osteosarcoma are relatively dismal. As immunotherapy has revolutionized treatment for solid tumors, exploring novel immunotherapy-related therapeutic targets for osteosarcoma is important. In this study, we aimed to establish the connection between RNA modification and immunotherapy in osteosarcoma to identify novel therapeutic targets. An RNA modification-related signature was first developed using weight gene correlation network analysis and a machine-learning algorithm, random forest. The signature's prognostic value, drug prediction, and immune characteristics were analyzed. EIF4G2 from the signature was next identified as a critical immunotherapy determinant. EIF4G2 could also promote tumor proliferation, migration, and M2 macrophage migration by single-cell sequencing analysis and in vitro validation. Our signature and EIF4G2 are expected to provide valuable insights into the clinical management of osteosarcoma.

shinyTempSignal: an R shiny application for exploring temporal and other phylogenetic signals.

The molecular clock model is fundamental for inferring species divergence times from molecular sequences. However, its direct application may introduce significant biases due to sequencing errors, recombination events, and inaccurately labeled sampling times. Improving accuracy necessitates rigorous quality control measures to identify and remove potentially erroneous sequences. Furthermore, while not all branches of a phylogenetic tree may exhibit a clear temporal signal, specific branches may still adhere to the assumptions, with varying evolutionary rates. Supporting a relaxed molecular clock model better aligns with the complexities of evolution. The root-to-tip regression method has been widely used to analyze the temporal signal in phylogenetic studies and can be generalized for detecting other phylogenetic signals. Despite its utility, there remains a lack of corresponding software implementations for broader applications. To address this gap, we present shinyTempSignal, an interactive web application implemented with the shiny framework, available as an R package and publicly accessible at https://github.com/YuLab-SMU/shinyTempSignal. This tool facilitates the analysis of temporal and other phylogenetic signals under both strict and relaxed models. By extending the root-to-tip regression method to diverse signals, shinyTempSignal helps in the detection of evolving features or traits, thereby laying the foundation for deeper insights and subsequent analyses.

Enhancement of de novo lipogenesis by the IDH1 and IDH2-dependent reverse TCA cycle maintains the growth and angiogenic capacity of bone marrow-derived endothelial progenitor cells under hypoxia.

BACKGROUND: Bone marrow-derived endothelial progenitor cells (EPCs) play a dynamic role in maintaining the structure and function of blood vessels. But how these cells maintain their growth and angiogenic capacity under bone marrow hypoxic niche is still unclear. This study aims to explore the mechanisms from a perspective of cellular metabolism. METHODS: XFe96 Extracellular Flux Analyzer was used to analyze the metabolic status of EPCs. Gas Chromatography-Mass Spectrometry (GC-MS) was used to trace the carbon movement of 13C-labeled glucose and glutamine under 1 % O2 (hypoxia) and ∼20 % O2 (normoxia). Moreover, RNA interference, targeting isocitrate dehydrogenase-1 (IDH1) and IDH2, was used to inhibit the reverse tricarboxylic acid (TCA) cycle and analyze metabolic changes via isotope tracing as well as changes in cell growth and angiogenic potential under hypoxia. The therapeutic potential of EPCs under hypoxia was investigated in the ischemic hindlimb model. RESULTS: Compared with normoxic cells, hypoxic cells showed increased glycolysis and decreased mitochondrial respiration. Isotope metabolic tracing revealed that under hypoxia, the forward TCA cycle was decreased and the reverse TCA cycle was enhanced, mediating the conversion of α-ketoglutarate (α-KG) into isocitrate/citrate, and de novo lipid synthesis was promoted. Downregulation of IDH1 or IDH2 under hypoxia suppressed the reverse TCA cycle, attenuated de novo lipid synthesis (DNL), elevated α-KG levels, and decreased the expression of hypoxia inducible factor-1α (HIF-1α) and vascular endothelial growth factor A (VEGFA), eventually inhibiting the growth and angiogenic capacity of EPCs. Importantly, the transplantation of hypoxia-cultured EPCs in a mouse model of limb ischemia promoted new blood vessel regeneration and blood supply recovery in the ischemic area better than the transplantation of normoxia-cultured EPCs. CONCLUSIONS: Under hypoxia, the IDH1- and IDH2-mediated reverse TCA cycle promotes glutamine-derived de novo lipogenesis and stabilizes the expression of α-KG and HIF-1α, thereby enhancing the growth and angiogenic capacity of EPCs.

OsGA3ox genes regulate rice fertility and plant height by synthesizing diverse active GA.

Gibberellin (GA) is an important hormone, which is involved in regulating various growth and development. GA biosynthesis pathway and synthetase have been basically clarified. Gibberellin 3ß hydroxylase (GA3ox) is the key enzyme for the synthesis of various active GA. There are two GA3ox genes (OsGA3ox1 and OsGA3ox2) in rice, and their physiological functions have been preliminarily studied. However, it is not clear how they work together to synthesize active GA to regulate rice development. In this study, the knockout mutants ga3ox1 and ga3ox2 were obtained by CRISPR/Cas9 technology. The pollen fertility of ga3ox1 decreased significantly, while the plant height of ga3ox2 decreased significantly. It shows that OsGA3ox1 is necessary for normal pollen development, while OsGA3ox2 is necessary for stem and leaf elongation. Tissue expression analysis showed that OsGA3ox1 was mainly expressed in unopened flowers, while OsGA3ox2 was mainly expressed in unexpanded leaves. The GA in different tissues of wild type (WT), and two ga3ox mutants were detected. It was found that pollen fertility is most closely related to the content of GA7, and plant height is most closely related to the content of GA1. It was found that OsGA3ox1 catalyzes GA9 to GA7 in flowers, which is closely related to pollen fertility; OsGA3ox2 catalyzes the GA20 to GA1 in unexpanded leaves, thereby regulating plant height; OsGA3ox1 catalyzes the GA19 to GA20 in roots, regulating the generation of GA3. OsGA3ox1 and OsGA3ox2 respond to developmental and environmental signals, and cooperate to synthesize endogenous GA in different tissues to regulate rice development. This study provides a reference for clarifying its role in GA biosynthesis pathway and further understanding the function of OsGA3ox.

Promotion of NAD+ recycling by the hypoxia-induced shift in the lactate dehydrogenase isozyme profile reduces the senescence of human bone marrow-derived endothelial progenitor cells.

Expansion of bone marrow-derived endothelial progenitor cells (EPCs) in vitro to obtain required cell numbers for therapeutic applications faces the challenge of growing cell senescence under the traditional normoxic culture condition. We previously found that 1% O2 hypoxic culture condition is favorable for reducing senescence of EPCs, but the mechanisms underlying the favorability are still unclear. Here, we found that, compared with normoxia, hypoxia induced a shift in lactate dehydrogenase (LDH) isozyme profile, which manifested as decreased LDH2 and LDH1 and increased LDH5, LDH4 and total LDHs. Moreover, under hypoxia, EPCs presented higher LDH activity, which could promote the conversion of pyruvate to lactate, as well as a higher level of NAD+, Bcl2 interacting protein 3 (BNIP3) expression and mitophagy. Additionally, under hypoxia, knock-down of the LDHA subunit increased the LDH2 and LDH1 levels and knock-down of the LDHB subunit increased the LDH5 level, while the simultaneous knock-down of LDHA and LDHB reduced total LDHs and NAD+ level. Inhibition of NAD+ recycling reduced BNIP3 expression and mitophagy and promoted cell senescence. Taken together, these data demonstrated that 1% O2 hypoxia induces a shift in the LDH isozyme profile, promotes NAD+ recycling, increases BNIP3 expression and mitophagy, and reduces EPC senescence. Our findings contribute to a better understanding of the connection between hypoxic culture conditions and the senescence of bone marrow-derived EPCs and provide a novel strategy to improve in vitro expansion of EPCs.

AtSAMS regulates floral organ development by DNA methylation and ethylene signaling pathway.

S-adenosylmethionine synthase is the key enzyme involved in the biosynthesis of S-adenosylmethionine, which serves as the universal methyl group donor and a common precursor for the biosynthesis of ethylene and polyamines. However, little is known about how SAMS controls plant development. Here, we report that the abnormal floral organ development in the AtSAMS-overexpressing plants is caused by DNA demethylation and ethylene signaling. The whole-genome DNA methylation level decreased, and ethylene content increased in SAMOE. Wild-type plants treated with DNA methylation inhibitor mimicked the phenotypes and the ethylene levels in SAMOE, suggesting that DNA demethylation enhanced ethylene biosynthesis, which led to abnormal floral organ development. DNA demethylation and elevated ethylene resulted in changes in the expression of ABCE genes, which is essential for floral organ development. Furthermore, the transcript levels of ACE genes were highly correlated to their methylation levels, except for the down-regulation of the B gene, which might have resulted from demethylation-independent ethylene signaling. SAMS-mediated methylation and ethylene signaling might create crosstalk in the process of floral organ development. Together, we provide evidence that AtSAMS regulates floral organ development by DNA methylation and ethylene signaling pathway.

Hypoxia-induced reprogramming of glucose-dependent metabolic pathways maintains the stemness of human bone marrow-derived endothelial progenitor cells.

The benefits of hypoxia for maintaining the stemness of cultured human bone marrow-derived endothelial progenitor cells (BM EPCs) have previously been demonstrated but the mechanisms responsible remain unclear. Growing evidences suggest that cellular metabolism plays an important role in regulating stem cell fate and self-renewal. Here we aimed to detect the changes of glucose metabolism and to explore its role on maintaining the stemness of BM EPCs under hypoxia. We identified the metabolic status of BM EPCs by using extracellular flux analysis, LC-MS/MS, and 13C tracing HPLC-QE-MS, and found that hypoxia induced glucose metabolic reprogramming, which manifested as increased glycolysis and pentose phosphate pathway (PPP), decreased tricarboxylic acid (TCA) and mitochondrial respiration. We further pharmacologically altered the metabolic status of cells by employing various of inhibitors of key enzymes of glycolysis, PPP, TCA cycle and mitochondria electron transport chain (ETC). We found that inhibiting glycolysis or PPP impaired cell proliferation either under normoxia or hypoxia. On the contrary, inhibiting pyruvate oxidation, TCA or ETC promoted cell proliferation under normoxia mimicking hypoxic conditions. Moreover, promoting pyruvate oxidation reverses the maintenance effect of hypoxia on cell stemness. Taken together, our data suggest that hypoxia induced glucose metabolic reprogramming maintains the stemness of BM EPCs, and artificial manipulation of cell metabolism can be an effective way for regulating the stemness of BM EPCs, thereby improving the efficiency of cell expansion in vitro.

Wild-Type Isocitrate Dehydrogenase-Dependent Oxidative Decarboxylation and Reductive Carboxylation in Cancer and Their Clinical Significance.

The human isocitrate dehydrogenase (IDH) gene encodes for the isoenzymes IDH1, 2, and 3, which catalyze the conversion of isocitrate and α-ketoglutarate (α-KG) and are required for normal mammalian metabolism. Isocitrate dehydrogenase 1 and 2 catalyze the reversible conversion of isocitrate to α-KG. Isocitrate dehydrogenase 3 is the key enzyme that mediates the production of α-KG from isocitrate in the tricarboxylic acid (TCA) cycle. In the TCA cycle, the decarboxylation reaction catalyzed by isocitrate dehydrogenase mediates the conversion of isocitrate to α-KG accompanied by dehydrogenation, a process commonly known as oxidative decarboxylation. The formation of 6-C isocitrate from α-KG and CO2 catalyzed by IDH is termed reductive carboxylation. This IDH-mediated reversible reaction is of great importance in tumor cells. We outline the role of the various isocitrate dehydrogenase isoforms in cancer, discuss the metabolic implications of interference with IDH, summarize therapeutic interventions targeting changes in IDH expression, and highlight areas for future research.

Exploring Epigenomic Datasets by ChIPseeker.

In many aspects of life, epigenetics, or the altering of phenotype without changes in sequences, play an essential role in biological function. A vast number of epigenomic datasets are emerging as a result of the advent of next-generation sequencing. Annotation, comparison, visualization, and interpretation of epigenomic datasets remain key aspects of computational biology. ChIPseeker is a Bioconductor package for performing these analyses among variable epigenomic datasets. The fundamental functions of ChIPseeker, including data preparation, annotation, comparison, and visualization, are explained in this article. ChIPseeker is a freely available open-source package that may be found at https://www.bioconductor.org/packages/ChIPseeker. © 2022 Wiley Periodicals LLC. Basic Protocol 1: ChIPseeker and epigenomic dataset preparation Basic Protocol 2: Annotation of epigenomic datasets Basic Protocol 3: Comparison of epigenomic datasets Basic Protocol 4: Visualization of annotated results Basic Protocol 5: Functional analysis of epigenomic datasets Basic Protocol 6: Genome-wide and locus-specific distribution of epigenomic datasets Basic Protocol 7: Heatmaps and metaplots of epigenomic datasets.

Stemness Analysis Uncovers That The Peroxisome Proliferator-Activated Receptor Signaling Pathway Can Mediate Fatty Acid Homeostasis In Sorafenib-Resistant Hepatocellular Carcinoma Cells.

Hepatocellular carcinoma (HCC) stem cells are regarded as an important part of individualized HCC treatment and sorafenib resistance. However, there is lacking systematic assessment of stem-like indices and associations with a response of sorafenib in HCC. Our study thus aimed to evaluate the status of tumor dedifferentiation for HCC and further identify the regulatory mechanisms under the condition of resistance to sorafenib. Datasets of HCC, including messenger RNAs (mRNAs) expression, somatic mutation, and clinical information were collected. The mRNA expression-based stemness index (mRNAsi), which can represent degrees of dedifferentiation of HCC samples, was calculated to predict drug response of sorafenib therapy and prognosis. Next, unsupervised cluster analysis was conducted to distinguish mRNAsi-based subgroups, and gene/geneset functional enrichment analysis was employed to identify key sorafenib resistance-related pathways. In addition, we analyzed and confirmed the regulation of key genes discovered in this study by combining other omics data. Finally, Luciferase reporter assays were performed to validate their regulation. Our study demonstrated that the stemness index obtained from transcriptomic is a promising biomarker to predict the response of sorafenib therapy and the prognosis in HCC. We revealed the peroxisome proliferator-activated receptor signaling pathway (the PPAR signaling pathway), related to fatty acid biosynthesis, that was a potential sorafenib resistance pathway that had not been reported before. By analyzing the core regulatory genes of the PPAR signaling pathway, we identified four candidate target genes, retinoid X receptor beta (RXRB), nuclear receptor subfamily 1 group H member 3 (NR1H3), cytochrome P450 family 8 subfamily B member 1 (CYP8B1) and stearoyl-CoA desaturase (SCD), as a signature to distinguish the response of sorafenib. We proposed and validated that the RXRB and NR1H3 could directly regulate NR1H3 and SCD, respectively. Our results suggest that the combined use of SCD inhibitors and sorafenib may be a promising therapeutic approach.

Biobanking in dentistry: A review.

Biobanks are not-for-profit services for the collection, processing, storage and distribution of biological samples and data for research and diagnostic purposes. In dentistry, biological materials and data obtained from questionnaires investigating oral conditions can be stored and used for large-scale studies on oral and systemic diseases. To give some examples: gene expression microarrays obtained on biobanked specimens were used in the identification of genetic alterations in oral cancer; efforts to identify genetic mechanisms behind dental caries have been based on an integrative analysis of transcriptome-wide associations and messenger RNA expression. One of the largest studies on facial pain was conducted using Biobank data. Cryopreservation of dental pulp stem cells is a common practice in tooth biobanks. With the exception of teeth and pulp, also leftover oral soft and hard tissues may represent a source of healthy samples that has rarely been exploited as yet. While biobanks are increasingly attracting the attention of the scientific community and becoming economically sustainable, a systematic approach to this resource in dentistry seems to be lacking. This review illustrates the applications of biobanking in dentistry, describing biobanked pathological and healthy samples and data, and discussing future developments.

Moxibustion Ameliorates Ovarian Reserve in Rats by Mediating Nrf2/HO-1/NLRP3 Anti-Inflammatory Pathway.

Diminished ovarian reserve (DOR) is an increasingly emerging reproductive disorder that disturbs reproductive-aged women, which is closely linked with inflammation. In clinic, moxibustion has already been applied for reproductive problems. In the present study, we examined the involvement of inflammation in DOR and investigated the effect of moxibustion for its anti-inflammatory activities. Methods. DOR rat model was established using tripterygium glycosides A tablets (TGs) suspension by intragastric administration and was then treated with either moxibustion or hormone replacement therapy (HRT), respectively. Estrus cycles were observed through vaginal cytology. Ovarian morphological alterations were observed by HE staining. The serum levels of follicle-stimulating hormone (FSH), estradiol (E 2), anti-Müllerian hormone (AMH), tumor necrosis factor alpha (TNF-α), and interleukin-10 (IL-10) were measured through ELISA. The expression levels of Nrf2, HO-1, and NLRP3 were detected using immunohistochemistry. Nrf2, HO-1, and NLRP3 mRNA were examined by RT-PCR. Results. Moxibustion improved estrus cycles, FSH, E 2, and AMH levels relative to DOR rats as well as HRT, while also inhibiting ovarian tissue injury. Anti-inflammatory cytokine IL-10 in peripheral blood was upregulated, and proinflammatory factor TNF-α was decreased after treatment with moxibustion. Moxibustion enhanced the expression of mRNA and protein of nuclear factor erythroid 2-related factor (Nrf2) and heme oxygenase-1 (HO-1); in the mean time, nucleotide-binding oligomerization domain-like receptor protein 3 (NLRP3) was suppressed. Conclusions. We demonstrated that moxibustion could ameliorate the ovarian reserve in rats induced by TGs. Overall, the effect of moxibustion was comparable to that of HRT. The underlying mechanism could be attributed to the anti-inflammatory effects of moxibustion, which suppressed NLRP3 activation by upregulating Nrf2/HO-1 signaling pathway.

[Effect of moxibustion on Nrf2/HO-1 signaling pathway in rats with diminished ovarian reserve].

OBJECTIVE: To observe the effect of moxibustion on Nrf2/HO-1 signaling pathway in rats with diminished ovarian reserve (DOR), and to explore the protective mechanism of moxibustion on ovarian reserve function. METHODS: Forty SD rats were randomly divided into a blank group, a model group, a moxibustion group and a hormone group, 10 rats in each group. The rats in the model group, moxibustion group and hormone group were treated with intragastric administration of tripterysium glycosides turbid liquid to prepare DOR model. The rats in the blank group were treated with intragastric administration of sodium chloride solution with the same volume, once a day for 14 days. The rats in the hormone group were treated with hormone sequential therapy for 14 days from the day of modeling; the rats in the moxibustion group were treated with moxibustion at bilateral "Shenshu" (BL 23) or "Guanyuan" (CV 4) and "Zhongwan" (CV 12) from the day of modeling, and the two groups acupoints were alternated every other day, 10 min each time, for 14 consecutive days. The estrus cycle was observed every day by vaginal exfoliated cell smear, and the estrus cycle disorder rate in each group was calculated. After the intervention, the HE staining was used to observe the histological morphology of ovaries; ELISA was used to detect the contents of follicle stimulating hormone (FSH), luteinizing hormone (LH), estradiol (E2), anti Mullerian hormone (AMH), superoxide dismutase (SOD) and malondialdehyde (MDA); the protein levels of Nrf2 and HO-1 in ovarian tissue were detected by immunohistochemistry; real-time PCR (TaqMan probe method) was used to detect the expression of Nrf2 and HO-1 mRNA. RESULTS: Compared with the blank group, the rate of estrus cycle disorder in the model group was increased (P<0.01); compared with the model group, the rate of estrus cycle disorder in the moxibustion group and hormone group was decreased (P<0.01). Compared with the blank group, the serum contents of FSH, LH and MDA in the model group were increased (P<0.01), and the serum contents of E2, AMH and SOD were decreased (P<0.01). Compared with the model group, the serum contents of FSH, LH and MDA in the moxibustion group and hormone group were decreased (P<0.01, P<0.05), and the serum contents of E2, AMH and SOD were increased (P<0.01). Compared with the blank group, the protein and mRNA expression of Nrf2 and HO-1 in the model group were decreased (P<0.01); compared with the model group, the protein and mRNA expressions of Nrf2 and HO-1 in the moxibustion group and hormone group were increased (P<0.01). CONCLUSION: Moxibustion could reduce the rate of estrus cycle disorder, improve the level of serum sex hormones and antioxidant stress in DOR rats, and the mechanism may be related to the regulation of Nrf2/HO-1 signaling pathway.

Improving the -3 dB bandwidth of micro-size LEDs through p-electrode patterns for visible light communication.

We systematically studied the effect of p-electrode patterns on the optical properties and -3dB bandwidth of micro-size LEDs. The current spreading distribution can be effectively improved via adjusting the number and shape of the p-electrode branch, thus increasing the injection saturation current density and decreasing the series resistance. Compared with the micro-size LED using a disk p-electrode, the saturation light output power and -3dB bandwidth of the micro-size LED using a six-branches spiral p-electrode increase by 39.48% and 76.61%, respectively. Such a p-electrode pattern is a promising solution for micro-size LED applications in both illumination and visible light communication systems.

Profiling miRNA expression in photo-thermo-sensitive male genic sterility line (PTGMS) PA64S under high and low temperature.

Peiai64S (PA64S) is a photo-thermo-sensitive genic male sterile line (PTGMS), with wide application in hybrid seed production in rice (Oryza sativa L.). Micro-RNAs are 21-24 nt, endogenously expressed small RNAs that have been characterized in various developmental stages of rice, but none have been studied with respect to the regulation of TGMS in rice. Here, we employed high-throughput sequencing to identify expression profiles of miRNAs in the anthers of PA64S at high (PA64S-H) and low temperature (PA64S-L). Two small RNA libraries from PA64S-H and PA64-L anthers were sequenced, and 263 known and 321 novel candidate miRNAs were identified. Based on the number of sequencing reads, a total of 133 known miRNAs were found to be differentially expressed between PA64S-H and PA64S-L. Target prediction showed that the target genes encode MYB and TCP transcription factors, and bHLH proteins. These target genes are related to pollen development and male sterility, suggesting that miRNA/targets may play roles in regulating TGMS in rice. Further, starch and sucrose metabolism pathways, sphingolipid metabolism, arginine and proline metabolism, and plant hormone signal transduction pathways were enriched by KEGG pathway annotation. These findings contribute to our understanding of the role of miRNAs during anther development and TGMS occurrence in rice.

The trehalose-6-phosphate synthase TPS5 negatively regulates ABA signaling in Arabidopsis thaliana.

KEY MESSAGE: The TPS5 negatively regulates ABA signaling by mediating ROS level and NR activity during seed germination and stomatal closure in Arabidopsis thaliana. Trehalose metabolism is important in plant growth and development and in abiotic stress response. Eleven TPS genes were identified in Arabidopsis, divided into Class I (TPS1-TPS4) and Class II (TPS5-TPS11). Although Class I has been shown to have TPS activity, the function of most members of Class II remains enigmatic. Here, we characterized the biological function of the trehalose-6-phosphate synthase TPS5 in ABA signaling in Arabidopsis. TPS5 expression was induced by ABA and abiotic stress, and expression in epidermal and guard cells was dramatically increased after ABA treatment. Loss-of-function analysis revealed that tps5 mutants (tps5-1 and tps5-cas9) are more sensitive to ABA during seed germination and ABA-mediated stomatal closure. Furthermore, the H2O2 level increased in the tps5-1 and tps5-cas9 mutants, which was consistent with the changes in the expression of RbohD and RbohF, key genes responsible for H2O2 production. Further, TPS5 knockout reduced the amounts of trehalose and other soluble carbohydrates as well as nitrate reductase (NR) activity. In vitro, trehalose and other soluble carbohydrates promoted NR activity, which was blocked by the tricarboxylic acid cycle inhibitor iodoacetic acid. Thus, this study identified that TPS5 functions as a negative regulator of ABA signaling and is involved in altering the trehalose content and NR activity.

A Node-Expressed Transporter OsCCX2 Is Involved in Grain Cadmium Accumulation of Rice.

Excessive cadmium (Cd) accumulation in grains of rice (Oryza sativa L.) is a risk to food security. The transporters in the nodes of rice are involved in the distribution of mineral elements including toxic elements to different tissues such as grains. However, the mechanism of Cd accumulation in grains is largely unknown. Here, we report a node-expressed transporter gene, OsCCX2, a putative cation/calcium (Ca) exchanger, mediating Cd accumulation in the grains of rice. Knockout of OsCCX2 caused a remarkable reduction of Cd content in the grains. Further study showed that disruption of this gene led to a reduced root-to-shoot translocation ratio of Cd. Moreover, Cd distribution was also disturbed in different levels of internode and leaf. OsCCX2 is localized to plasma membrane, and OsCCX2 is mainly expressed in xylem region of vascular tissues at the nodes. OsCCX2 might function as an efflux transporter, responsible for Cd loading into xylem vessels. Therefore, our finding revealed a novel Cd transporter involved in grain Cd accumulation, possibly via a Ca transport pathway in the nodes of rice.

RPS9M, a Mitochondrial Ribosomal Protein, Is Essential for Central Cell Maturation and Endosperm Development in Arabidopsis.

During double fertilization of angiosperms, the central cell of the female gametophyte fuses with a sperm cell to produce the endosperm, a storage tissue that nourishes the developing embryo within the seed. Although many genetic mutants defective in female gametophytic functions have been characterized, the molecular mechanisms controlling the specification and differentiation of the central cell are still not fully understood. Here, we report a mitochondrial ribosomal protein, RPS9M, is required for central cell maturation. RPS9M was highly expressed in the male and female gametophytes before and after double fertilization. The female gametophytes were defective in the rps9m mutant specifically concerning maturation of central cells. The morphological defects include unfused polar nuclei and smaller central vacuole in central cells. In addition, embryo initiation and early endosperm development were also severely affected in rps9m female gametophytes even after fertilized with wild type pollens. The RPS9M can interact with ANK6, an ankyrin-repeat protein in mitochondria previously reported to be required for fertilization. The expression pattern and mutant phenotype of RPS9M are similar to those of ANK6 as well, suggesting that RPS9M may work together with ANK6 in controlling female gametophyte development, possibly by regulating the expression of some mitochondrial proteins.

Comparison of dietary energy and macronutrient intake at different levels of glucose metabolism.

The aim of this study was to evaluate energy and glycolipid metabolism by determining the intake of energy and macronutrients in persons with differing glucose metabolisms. In total, 147 patients who were newly diagnosed with pre-diabetes, 177 patients with diabetes, 139 patients who were previously diagnosed with diabetes, and 140 patients with normal blood sugar were selected from the 103rd Regiment of Xinjiang. All patients had Han nationality and were over 30 years old. Their energy and macronutrient intakes were analyzed from data obtained from a 3-day food weighing household investigation. Compared to the normal group, the patients in the previously and newly diagnosed diabetic groups were older, less educated, and had a greater prevalence of hypertension (P<0.05). Compared to the normal group, patients with abnormal glucose metabolism had larger waist circumferences; higher systolic and diastolic blood pressure; higher postprandial glucose; higher total cholesterol; lower high-density lipoprotein cholesterol (HDL-C; P<0.05); higher intakes of energy, carbohydrates, and fat; and lower intakes of protein and fiber. In addition, the newly and previously diagnosed patients had higher fasting glucose levels (P<0.05). Compared to the normal group, patients with abnormal glucose metabolism in each sex subgroup also had larger waist circumferences, and more men had abdominal obesity (P<0.05). Diabetes or pre-diabetes patients had a higher intake of energy, carbohydrates, and fat, but a lower intake of proteins and fiber. They had severe abdominal obesity, a greater prevalence of hypertension, higher total cholesterol levels, lower HDL-C, and poor blood glucose and glycosylated hemoglobin levels, especially postprandial plasma glucose levels.