Design and Realization of Visual and Contact-Type Fast Charging Power Source.

Charging power supplies with both fast and visualization functions have a wide range of applications in the information and new energy industries. In this paper, the visualized and contact-type fast charging power supply based on WO3 film and Zn sheet is presented, and the prototype devices are fabricated. Different with the charging method of conventional batteries, charging is achieved by a Zn sheet contacting with a WO3 film moistened with water, resulting in a rapid discoloration of WO3. Theoretical investigation indicates that the interaction between Zn sheet and water molecules is the primary cause of the color change in the WO3 film. The WO3 film completes the colouring state within 10 s in the presence of Zn sheet and water, and the open-circuit voltage of the device is 0.7 V, which can be used to drive various electronics by series-parallel connection. This research introduces a novel method to induce colouring of WO3 films and proposes a fast charging mode different from traditional power sources. It provides valuable insights for the future development of fast charging in the field of electrical energy.

Enhanced Low-Temperature Resistance of Lithium-Metal Rechargeable Batteries Based on Electrolyte Including Ethyl Acetate and LiDFOB Additives.

To meet the demand for higher energy density in lithium-ion batteries and expand their application range, coupling lithium metal anodes with high-voltage cathodes is an ideal solution. However, the compatibility between lithium metal batteries and electrolytes affects their applicability. In this study, proposes a locally concentrated electrolyte based on ethyl acetate (EA) as the solvent, lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) as the lithium salt, and lithium difluorooxoborate (LiDFOB) as a sacrificial agent to enhance the low-temperature and high-voltage endurance of Li//Lithium cobalt oxide (LCO) batteries. The Li//LCO battery can operate within the voltage range of 3 to 4.5 V, with an initial discharge specific capacity of 174.5 mAh g-1 at 20 °C. At -40 °C, after 200 cycles, the capacity retention rate is 87.7 %. It can operate under extreme conditions of -70 °C, with a discharge specific capacity of 112.6 mAh g-1. Additionally, LCO//HC batteries using this electrolyte demonstrate excellent performance. Present work provides a new perspective for the optimization of electrolytes for low-temperature lithium-ion batteries.

Concentration controlling of carboxylic ester-based electrolyte for low temperature lithium-ion batteries.

Low temperature has been a major challenge for lithium-ion batteries (LIBs) to maintain satisfied electrochemical performance, and the main reason is the deactivation of electrolyte with the decreasing temperature. To address this point, in present work, we develop a low-temperature resistant electrolyte which includes ethyl acetate (EA) and fluoroethylene carbonate (FEC) as solvent and lithium difluoro(oxalato)borate (LiDFOB) as the primary lithium salt. Due to the preferential decomposition of LiDFOB and FEC, a solid electrolyte interface rich in LiF is formed on the lithium metal anodes (LMAs) and lithium cobalt oxide (LCO) cathodes, contributing to higher stability and rapid desolvation of Li+ ions. The batteries with the optimized electrolyte can undergo cycling tests at -40 °C, with a capacity retention of 83.9 % after 200 cycles. Furthermore, the optimized electrolyte exhibits excellent compatibility with both LCO cathodes and graphite (Gr) anodes, enabling a Gr/LCO battery to maintain a capacity retention of 90.3 % after multiple cycles at -25 °C. This work proposes a cost-effective electrolyte that can activate potential LIBs in practical scenarios, especially in low-temperature environments.

Enhanced low-temperature resistance of lithium-ion batteries based on methyl propionate-fluorinated ethylene carbonate electrolyte.

Low temperature has been a major challenge for lithium-ion batteries to maintain satisfied electrochemical performance, as it leads to poor rechargeability and low capacity retention. Traditional carbonate solvents, vinyl carbonate and dimethyl carbonate are indispensable components of commercial electrolytes. However, the higher melting point of these carbonate solvents causes their electrical conductivity to be easily reduced when temperatures drop below zero, limiting their ability to facilitate lithium ion transport. In this work, we demonstrate that the use of methyl propionate (MP) carboxylate and fluorocarbonate vinyl (FEC) electrolytes can overcome the limitations of low temperature cycling. Compared with carbonate electrolyte, MP has the characteristics of low melting point, low viscosity and low binding energy with Li+, which is crucial to improve the low temperature performance of the battery, while FEC is an effective component to inhibit the side reaction between MP and lithium metal. The carefully formulated MP-based electrolyte can generate a solid electrolyte interface with low resistance and rich in inorganic substances, which is conducive to the smooth diffusion of Li+, allowing the battery to successfully cycle at a high rate of 0.5 C at -20 °C, and giving it a reversible capacity retention rate of 65.3% at -40oC. This work designs a promising advanced electrolyte and holds the potential to overcome limitations of lithium-ion batteries in harsh conditions.

Flexible Self-Powered Energy Systems Based on H2 O/Ni2+ Intercalated Nix V2 O5 ⋠nH2 O.

The development of portable electronic devices has created greater demands for multifunctional energy integration systems. Self-powered systems have gained widespread interest because they can collect and storage renewable environmental energy and provide stable electricity to electronic devices. Herein, we developed a flexible self-charging energy system, involving textile-based zinc-ion hybrid (ZIHC) and triboelectric nanogenerator (TENG), which demonstrates wearable, compatibility, lightweight and can quickly harvest and store energy. Nix V2 O5 ⋅ nH2 O (NVO) loaded on carbon cloth (CC) with Ni2+ /H2 O ions intercalated as the cathode was assembled with activated CC to form a ZIHC, which has a voltage range of 2.0 V and capacitance value of 267.1 mF cm-2 as well as good charge and discharge rates and excellent cycling stability. At the same time, the NVO/CC can be assembled with PDMS to form a TENG achieving a maximum instantaneous power of 18.5 mW cm-2 . The device can be flexibly worn over the body to continuously harvest and store biomechanical energy and charge the electronic wristwatch successfully. This work demonstrates great convenience and promising practical applications as sustainable flexible energy system for portable electronic devices.

Flexible, Wash-Resistant Human Mechanical Energy Harvesting and Storage System for Monitoring Human Movement.

The rapid development of personal portable electronic devices has brought an increasingly urgent need for flexible and portable power sources. Herein, a low-cost, wearable, efficient, sustainable energy harvesting and storage system for human motion detection has been developed, based on a supercapacitor (SC) and triboelectric nanogenerator (TENG). Carbon cloth (CC)-loaded ZnO/ZnS nanoarrays and a PVD-treated polyurethane conductive sponge are employed as positive and negative triboelectric friction layers, respectively. Besides, flexible and robust silicone rubber provides stable output performance and enables the TENG to harvest mechanical energy from human motion even under complex conditions. As a result, it shows excellent electrical output performance in terms of the open-circuit voltage, short-circuit current, and average power density, reaching 175 V, 12 µA, and 816.7 mW m-2, respectively. These outstanding performances enable the TENG to effectively charge an all-solid-state symmetrical SC (MnO2/LiMn2O4@CC//MnO2/LiMn2O4@CC) and subsequently store it as electrochemical energy for sustainable power supply. Because of the flexible all-texture-type structure of the entire system, it is capable of monitoring the human body's movement. This work has a promising future in random mechanical energy harvesting and storage, as well as human motion tracking.

Washable All-in-One Self-Charging Power Unit Based on a Triboelectric Nanogenerator and Supercapacitor for Smart Textiles.

Lightweight, portability, and sustainability have become key factors of the power source for the rapid development of multifunctional wearable electronic devices. In this work, a washable, wearable, and durable self-charging system for human motion energy harvesting and storage based on asymmetric supercapacitors (ASCs) and triboelectric nanogenerators (TENGs) is investigated. The all-solid-state flexible ASC is composed of a cobalt-nickel layered double hydroxide grown on a carbon cloth (CoNi-LDH@CC) as the positive electrode and activated carbon cloth (ACC) as the negative electrode and exhibits the performance of small size, high flexibility, and superior stability. The device was able to provide a capacity of 345 mF cm-2 and a cycle retention rate of 83% after 5000 cycles, which shows great potential as an energy storage unit. Additionally, flexible silicon rubber-coated carbon cloth (CC) is waterproof and soft and can be used as a TENG textile to gain energy for stable charging of an ASC, which presents an open-circuit voltage and short-circuit current of 280 V and 4 µA, respectively. The ASC and TENG can be assembled to continuously collect and store energy, which provides an all-in-one self-charging system qualified with washable and durable for potential applications in wearable electronics.

Asymmetric supercapacitors based on SnNiCoS ternary metal sulfide electrodes.

While metal sulfides have extensively investigated as electrode materials for supercapacitors, the further optimization of their material system is still necessary to achieve satisfied performance. In this work, we reported the synthesis of ternary metal sulfide SnNiCoS and its application as electrode material of asymmetric supercapacitors, in which active carbon is used as the other electrode. For control experiments, asymmetric supercapacitors based on single metal sulfide CoS and binary metal sulfide NiCoS are also fabricated and investigated. The results show that the nanospherical SnNiCoS achieves the best performance. Ternary sulphide materials offer more redox than corresponding single-metal sulphides due to the synergy among various transition metal elements. The specific capacitance is 18.6 F cm-2at current density of 5 mA·cm-2. An energy density of 937.2µWh cm-2is achieved at a power density of 4000µW·cm-2. After 8000 cycles, the capacity retention rate is 82.9%. Present work indicates that SnNiCoS ternary metal sulfide could be a promising composite for high performance supercapacitors.

Flexible Triboelectric Nanogenerators Based on Electrospun Poly(vinylidene fluoride) with MoS2/Carbon Nanotube Composite Nanofibers.

With the miniaturization of wearable smart devices, the demand for portable and sustainable power sources is increasing. Herein, a flexible and lightweight triboelectric nanogenerator (PMC-TENG) was fabricated with MoS2/carbon nanotube (MC)-doped PVDF as the friction substrate based on electrospinning for harvesting random body motion energy under complex mechanical deformations. The charge density on the friction surface of PVDF nanofibers was found to increase significantly as the introduced electron acceptor of the MC composite, and nylon as a clothing material for another friction layer simplifies the structure of the device. Upon optimization of the electrospinning preparation process, the output voltage of the prepared PMC-TENG can reach >300 V and the instantaneous power can reach 0.484 mW (∼6 cm × 6 cm). At the same time, the PMC-TENG remains stable over 3000 cycles and has the ability to charge a capacitor. The flexible device demonstrates an excellent capability of converting mechanical energy to electrical energy. Therefore, this study has good prospects for application in the field of power supply for portable electronic devices and others.

Enhanced performance of asymmetric supercapacitor based on NiZn-LDH@NiCoSe2electrode materials.

While supercapacitors have been widely studied as the next generation of energy storage devices, to develop active electrode materials for enhancing device performance is still challenging. Herein, we fabricated asymmetric supercapacitors based on NiZn-Layered double hydroxide (LDH) @NiCoSe2hierarchical nanostructures as electrode materials. The NiZn-LDH@NiCoSe2composites are deposited on Ni foam by a two-step strategy, in which NiZn-LDH nanosheets were firstly grown on Ni foam by hydrothermal method, and then NiCoSe2particles were prepared by electrodeposition. Due to the synergistic effect between NiZn-LDH and NiCoSe2, excellent device performance was achieved. In a three-electrode system, the NiZn-LDH@NiCoSe2exhibits a specific capacitance of 2980 F g-1at 1 A g-1. Furthermore, the asymmetric supercapacitor of NiZn-LDH@NiCoSe2//activated carbon (AC) device was assembled, which exhibits the energy density of 49.2 Wh kg-1at the power density of 160 W kg-1, with the capacity retention rate is 91% after 8000 cycles. The results indicates that NiZn-LDH@NiCoSe2is a promising candidate as electrode materials for efficient energy storage devices.

Targeting Cd coping mechanisms for stress tolerance in Brassica napus under spiked-substrate system: from physiology to remediation perspective.

Cadmium (Cd) is a prevalent, non-essential, carcinogenic, and hazardous heavy metal that reduces plant productivity and capacity of arable land area around the globe. In the present substrate-based pot study, seedlings of Brassica napus 180015 were grown equidistantly in the spiked-substrate medium for 60 days under increasing concentrations of Cd (0, 10, 20, 30, 40, 50 mg kg-1). Following harvest, the morpho-physio-biochemical, antioxidative, and Cd-induced tolerance responses were evaluated in B. napus under an increasing Cd stress regime. Additionally, these parameters were also investigated to select the plant's threshold tolerance limit for Cd under the spiked-substrate system. B. napus showed dynamic behavior regarding morpho-physio-biochemical attributes, including agronomic features, biomass, photosynthetic pigments, relative water content under increased Cd toxicity. Cd stress-induced hydrogen peroxide (H2O2) production with high MDA contents and passive EL, followed by the orchestration of both enzymatic (SOD, POD, APX, CAT, and GR) and non-enzymatic antioxidants (flavonoids, TPC, TPA, proline, and total soluble protein) up to a certain limit. In addition, Cd-induced stress upregulated transcriptional levels of antioxidative enzyme SOD, POD, APX, GR, and MT encoded genes in B. napus. The increasing trend of Cd accumulation in different tissues at the highest Cd concentration was as follows: root > leaf > stem. In spiked substrate system, B. napus demonstrated improved metal extractability performance and a high potential for phyto-management of low to moderate Cd contamination, implying that this study could be used for integrative breeding programs and decontaminating heavy metals in real contaminated scenarios.Novelty statementThis study provides an insight into Cd-coping mechanisms of oilseed rape involved in alleviating toxicity and simultaneous phyto-management of increasing Cd concentration under spiked substrate system. The current study is the first scientific evidence of using a Cd-spiked soilless substrate medium. The present study will further strengthen our understanding of Cd-instigated positive responses in B. napus. Furthermore, it will provide a useful basis for integrative breeding programs and decontaminating heavy metals in real contaminated scenarios.

Microbe-EDTA mediated approach in the phytoremediation of lead-contaminated soils using maize (Zea mays L.) plants.

In the current study, we investigated the potential of Cronobacter sakazakii- ethylenediaminetetraacetic acid (EDTA) assisted phytoremediation potential of Zea mays L. to remediate lead (Pb)-contaminated soils. The C. sakazakii exhibited various stress tolerance mechanisms via plant growth promoting (PGP) traits, intrinsic extracellular enzyme production and antibiotic resistance. A greenhouse experiment was conducted to examine the dual effects of plant growth promoting endophytic bacteria (PGPEB)-chelator synergy in maize plants under different Pb contaminated soil regimes. C. sakazaii-EDTA (5 mM EDTA kg-1) complex significantly (p < 0.05) enhanced plant growth and biomass (48.91%); chlorophyll a, b and carotenoid contents (27.26%, 25.02% and 42.09%); relative water content (61.33%); proline content (63.60%); root and shoot Pb accumulation capacity (52.31% and 44.71%) in Pb contaminated soils. This may suggest the efficacy of current approach in enhancing plant tolerance capability toward Pb-uptake and phytoremediation capacity. Moreover, maize plants showed differential response to Pb availability in soil-1 (S1; Pb spiked soil, 500 mg kg-1) and soil-2 (S2; aged-contaminated soil) under various treatments. We describe the intriguing role of C. sakazakii-EDTA-maize system for Pb decontamination which can be used as a base line to explore the proposed combinatorial approach for long-term trails under field conditions for reclamation of Pb-contaminated soils.HighlightsThe PGPEB-EDTA mediated potential of Z. mays against Pb spiked and industrial contaminated soils is noticed.Increased tolerance of Z. mays against Pb in association with C. sakazakii, and EDTA is reported first time.Enhanced accumulation of metals by Z. mays is reported under combined treatment of C. sakazakii, and EDTA.Inoculation of plants with C. sakazakii, and EDTA has positive effects on growth and accumulation of Pb by Z. mays.

Enhanced Energy Density of Coaxial Fiber Asymmetric Supercapacitor Based on MoS2 @Fe2 O3 /Carbon Nanotube Paper and Ni(OH)2 @NiCo2 O4 /Carbon Nanotube Fiber Electrodes.

Fiber supercapacitors are promising energy storage devices for potential application in wearable and miniaturized portable electronics, which currently suffer from difficulties in achieving high capacitance and energy density synchronously owing to the limited specific surface area of the electrode materials and material incompatibility between the two electrodes. Herein, a strategy is developed for the manufacture of coaxial asymmetric fiber supercapacitors by wrapping a core of PVA-KOH gel electrolyte-coated Ni(OH)2 @NiCo2 O4 /CNT fibers with MoS2 @Fe2 O3 /CNT paper. The as-prepared coaxial fiber asymmetric supercapacitors exhibit a specific capacitance of 373 mF cm-2 (at a current density of 2 mA cm-2 ) and energy density of 0.13 mW h cm-2 (at a power density of 3.2 mW cm-2 ), and also show good rate capability, long cycle life, and excellent flexibility. This work provides the possibility for the practical application of fiber supercapacitors in wearable and portable energy storage equipment.

Rice fatty acyl-CoA synthetase OsACOS12 is required for tapetum programmed cell death and male fertility.

MAIN CONCLUSION: Loss of function mutation of rice OsACOS12 impairs lipid metabolism-mediated anther cuticle and pollen wall formation, and interferes with tapetum programmed cell death, leading to male sterility. Acyl-CoA Synthetase (ACOS) is one of the enzymes activating fatty acids for various metabolic functions in plants. Here, we show that OsACOS12, an orthologue of Arabidopsis ACOS5 in rice, is crucial for rice fertility. Similar to acos5, osaocs12 mutant had no mature pollen. But unlike acos5, osaocs12 produced defective anthers lacking cutin and Ubisch bodies on the epidermal and inner surfaces, respectively, and delayed programmed cell death (PCD)-induced tapetum degradation. Those phenotypic changes were evident at stage 10, during which OsACOS12 had its maximum expression in tapetal cells and microspores. Chemical analysis revealed that the levels of anther cuticular lipid components (wax and cutin monomers) were significantly reduced in osaocs12, while the expression levels of three known lipid biosynthetic genes were unchanged. Recombinant OsACOS12 enzyme was shown to catalyze the conversion of C18:1 fatty acid to C18:1 CoA in vitro. Phylogenetic analysis indicated that OsACOS12 is an ancient and conserved enzyme associated with the plant's colonization to earth. Collectively, our study suggests that OsACOS12 is an ancient enzyme participating in a conserved metabolic pathway for diversified biochemical functions to secure male reproduction in plants.

Role of Lipid Metabolism in Plant Pollen Exine Development.

Pollen plays important roles in the life cycle of angiosperms plants. It acts as not only a biological protector of male sperms but also a communicator between the male and the female reproductive organs, facilitating pollination and fertilization. Pollen is produced within the anther, and covered by the specialized outer envelope, pollen wall. Although the morphology of pollen varies among different plant species, the pollen wall is mainly comprised of three layers: the pollen coat, the outer exine layer, and the inner intine layer. Except the intine layer, the other two layers are basically of lipidic nature. Particularly, the outer pollen wall layer, the exine, is a highly resistant biopolymer of phenylpropanoid and lipidic monomers covalently coupled by ether and ester linkages. The precise molecular mechanisms underlying pollen coat formation and exine patterning remain largely elusive. Herein, we summarize the current genetic, phenotypic and biochemical studies regarding to the pollen exine development and underlying molecular regulatory mechanisms mainly obtained from monocot rice (Oryza sativa) and dicot Arabidopsis thaliana, aiming to extend our understandings of plant male reproductive biology. Genes, enzymes/proteins and regulatory factors that appear to play conserved and diversified roles in lipid biosynthesis, transportation and modification during pollen exine formation, were highlighted.

Mutation in CSA creates a new photoperiod-sensitive genic male sterile line applicable for hybrid rice seed production.

Rice is a major staple food worldwide. Making hybrid rice has proved to be an effective strategy to significantly increase grain yield. Current hybrid rice technologies rely on male sterile lines and have been used predominantly in indica cultivars. However, intrinsic problems exist in the implementation of these technologies, such as limited germplasms and unpredictable conversions from sterility to fertility in the field. Here, we describe a photoperiod-controlled male sterile line, carbon starved anther (csa), which contains a mutation in an R2R3 MYB transcription regulator of pollen development. This mutation was introduced into indica and japonica rice, and it rendered male sterility under short-day conditions and male fertility under long-day conditions in both lines. Furthermore, F(1) plants of csa and a restorer line JP69 exhibited heterosis (hybrid vigor), suggesting the feasibility of using this mutation to create hybrid rice. The csa-based photoperiod-sensitive male sterile line allows the establishment of a stable two-line hybrid system, which promises to have a significant impact on agriculture.

Rice CYP703A3, a cytochrome P450 hydroxylase, is essential for development of anther cuticle and pollen exine.

Anther cuticle and pollen exine act as protective envelopes for the male gametophyte or pollen grain, but the mechanism underlying the synthesis of these lipidic polymers remains unclear. Previously, a tapetum-expressed CYP703A3, a putative cytochrome P450 fatty acid hydroxylase, was shown to be essential for male fertility in rice (Oryza sativa L.). However, the biochemical and biological roles of CYP703A3 has not been characterized. Here, we observed that cyp703a3-2 caused by one base insertion in CYP703A3 displays defective pollen exine and anther epicuticular layer, which differs from Arabidopsis cyp703a2 in which only defective pollen exine occurs. Consistently, chemical composition assay showed that levels of cutin monomers and wax components were dramatically reduced in cyp703a3-2 anthers. Unlike the wide range of substrates of Arabidopsis CYP703A2, CYP703A3 functions as an in-chain hydroxylase only for a specific substrate, lauric acid, preferably generating 7-hydroxylated lauric acid. Moreover, chromatin immunoprecipitation and expression analyses revealed that the expression of CYP703A3 is directly regulated by Tapetum Degeneration Retardation, a known regulator of tapetum PCD and pollen exine formation. Collectively, our results suggest that CYP703A3 represents a conserved and diversified biochemical pathway for in-chain hydroxylation of lauric acid required for the development of male organ in higher plants.

Vernodalin Triggers ROS-Mediated Apoptosis in TPC-1 Human PapillaryThyroid Cancer Cells via Suppression of the MAPKs Signaling Pathway.

BACKGROUND: Thyroid Cancer (TC) is an endocrine organ malignancy that has become more common in recent decades. Vernodalin (VN), a cytotoxic sesquiterpene, has been reported to exhibit anticancer properties against human breast and liver cancer cells. However, no study has explored the efficacy of VN with respect to its antiproliferative and apoptotic action on human Papillary Thyroid Cancer cells (PTC). OBJECTIVE: The study intended to examine the antitumor and antiproliferative effects of VN and the apoptosis mechanisms underlying its action on TPC-1 human PTC cells. METHODS: In this study, we examined the VN cell viability by MTT assay; performed ROS measurement by DCFH staining method, MMP identification by Rh-123 staining method, and apoptotic morphological assay by employing AO/EB and DAPI stain method, and further, p38 MAPK/ERK/JNK cell proliferation markers were determined by western blotting technique. RESULTS: The findings showed that VN could inhibit the growth of PTC cells by increasing intracellular ROS, damaging MMP, and stimulating apoptosis in a concentration-dependent manner. The study demonstrated how VN inhibited TPC-1 cell viability by causing ROS-induced cell death via the MAPK signaling pathway. CONCLUSION: VN may serve as an agonist to impact apoptosis in PTC cells. In human PTC, VN could play an effective role in chemotherapy. More studies pertaining to animal tumor models are needed to prove its anti-cancer effectiveness in vivo.

5HT2A modulation attenuates pancreatic cancer induced pain mouse model by inhibiting HDAC.

PURPOSE: Patients have been severely suffered from cancer associated pain, and pancreatic cancer is the most severe form of cancer associated with pain. There are very few options available to manage it. The present report evaluated the effect of 5HT2A on pancreatic cancer associated pain. METHODS: Pancreatic cancer was induced by injecting SW 1,990 cells (~3×106 in a 20 µL suspension) into the pancreas and formed a 2-3-mm vesicle using an inoculator fitted with a 26-gauge needle in BALB/c-nu mice. Survival rate and body weight of the mice were observed. Pain behaviour testing was performed at the end of each week (third and fourth week) after surgery. Inflammatory mediators and HDAC 2 proteins were determined in the spinal tissue using quantitative real-time polymerase chain reaction. RESULTS: There was improvement in the survival rate and body weight in 5HT2A antagonist treated group than pancreatic cancer group of mice. Moreover, 5HT2A antagonist ameliorated the alteration in pain behaviour of pancreatic cancer mice. mRNA expression of HDAC2 and level of inflammatory cytokines were reduced in the spinal tissue of 5HT 2A antagonist treated group than pancreatic cancer group of mice. CONCLUSIONS: Data revealed that 5HT2A antagonist ameliorates pain associated with pancreatic cancer mice by HDAC inhibition and inflammatory cytokines. The result of investigation supports that modulation of 5HT2A receptor could be used clinically to protects neuropathic pain in pancreatic cancer.

Carbon starved anther encodes a MYB domain protein that regulates sugar partitioning required for rice pollen development.

In flowering plants, sink tissues rely on transport of carbohydrates from photosynthetic tissues (sources) for nutrition and energy. However, how sugar partitioning in plants is regulated at the molecular level during development remains unknown. We have isolated and characterized a rice (Oryza sativa) mutant, carbon starved anther (csa), that showed increased sugar contents in leaves and stems and reduced levels of sugars and starch in floral organs. In particular, the csa mutant had reduced levels of carbohydrates in later anthers and was male sterile. The csa mutant had reduced accumulation of (14)C-labeled sugars in anther sink tissue. CSA was isolated by map-based cloning and was shown to encode an R2R3 MYB transcription factor that was expressed preferentially in the anther tapetal cells and in the sugar-transporting vascular tissues. In addition, the expression of MST8, encoding a monosaccharide transporter, was greatly reduced in csa anthers. Furthermore, CSA was found to be associated in vivo and in vitro with the promoter of MST8. Our findings suggest that CSA is a key transcriptional regulator for sugar partitioning in rice during male reproductive development. This study also establishes a molecular model system for further elucidation of the genetic control of carbon partitioning in plants.