植物组蛋白H3K27me3去甲基化酶研究获重要进展

中科院遗传与发育生物学所曹晓风研究组对植物组蛋白去甲基化酶基因家族进行了系统鉴定和功能分析。该研究组首先建立了植物细胞内组蛋白去甲基化酶活性检测体系,通过该体系发现拟南芥REF6／JMJ12可以特异性地去除H3K27双甲基化和三甲基化修饰。表达REF6的植物与H3K27me,功能异常突变体具有相似的表型。     

Unraveling the electrophilic oxygen-mediated mechanism for alcohol electrooxidation on NiOOA

Aqueous organic electrosynthesis such as nucleophile oxidation reaction(NOR) is an economical and green approach.However,its development has been hindered by the inadequate understanding of the synergy between the electrochemical and non-electrochemical steps.In this study,we unravel the NOR me chanism for the primary alcohol/vicinal diol electro oxidation on NiO.Thereinto,the ele ctrochemical step is the generation of Ni³⁺-(OH)_ads,and the spontaneous reaction between Ni     

Inhibition of Wnt activity improves peri-implantation development of somatic cell nuclear transfer embryos

Somatic cell nuclear transfer(SCNT) can reprogram differentiated somatic cells into totipotency.Although pre-implantation development of SCNT embryos has greatly improved,most SCNT blastocysts are still arrested at the peri-implantation stage,and the underlying mechanism remains elusive.Here,we develop a 3D in vitro culture system for SCNT peri-implantation embryos and discover that persistent Wnt signals block the naive-to-primed pluripotency transition of epiblasts with aberrant H3K27me3 occup...     

Boosted on-chip energy storage with transistorsOA

<正>On-chip energy-storage devices play an important role in powering wireless environmental sensors and microelectrome chanical systems [1,2].Starting from the 1980s,on-chip energy-storage devices,including microbatteries and super capacitors,have been applied to power the real-time clock on a chip [3].These tiny batteries/supercapacitors enable the real-time clock to keep working when the electronics are off.In this way,electronic devices can be restarted with a valid time.With the develo...     

Extensive gene flow in secondary sympatry after allopatric speciationOA

In the conventional view,species are separate gene pools delineated by reproductive isolation(RI).In an alternative view,species may also be delineated by a small set of ’speciation genes’ without full RI,a view that has gained broad acceptance.A recent survey,however,suggested that the extensive literature on’speciation with gene flow’ is mostly(if not all) about exchanges in the early stages of speciation.There is no definitive evidence that the observed gene flow actually happened after speci...     

Construction of nanocarriers based on nucleic acids and their applications in nanobiology delivery systemsOA

In recent years,nanocarriers based on nucleic acids have emerged as powerful and novel nanocarriers that are able to meet the demand for cancer-cell-specific targeting.Functional dynamics analysis revealed good bio compatibility,low toxicity and programmable structures,and their advantages include controllable size and modifiability.The development of novel hybrids has focused on the distinct roles of biosensing,drug and gene delivery,vaccine transport,photosensitization,counteracting drug resis...     

What are species and how are they formed?OA

<正>In this issue of NSR,four papers address various aspects of speciation.The fifth one,to appear in the next issue,is on biodiversity and should ultimately be about speciation as well.As has always been the case in speciation research,the conclusion depends on what’species’are.This is true for Wang et al.[1] on post-speciation gene flow,Ma et al.[2] on hybridization speciation,Sun et al.[3] on sympatric speciation and Fan et al.[4]on species diversity.The conclusions would all be quite di...     

N,N-dimethylformamide tailors solvent effect to boost Zn anode reversibility in aqueous electrolyteOA

Rechargeable aqueous Zn batteries are considered as promising energy-storage devices because of their high capacity,environmental friendliness and low cost.However,the hydrogen evolution reaction and growth of dendritic Zn in common aqueous electrolytes severely restrict the application of Zn batteries.Here,we develop a simple strategy to suppress side reactions and boost the reversibility of the Zn electrode.By introducing 30%(volume fractions) N,N-dimethylformamide(DMF) to the 2 M Zn(CF_3<...     

A critical review of mineral-microbe interaction and co-evolution:mechanisms and applicationsOA

Mineral-microbe interactions play important roles in environmental change,biogeochemical cycling of elements and formation of ore deposits.Minerals provide both beneficial(physical and chemical protection,nutrients,and energy) and detrimental(toxic substances and oxidative pressure) effects to microbes,resulting in mineral-specific microbial colonization.Microbes impact dissolution,transformation and precipitation of minerals through their activity,resulting in either genetically controlled or m...     

The LRXs-RALFs-FER module controls plant growth and salt stress responses by modulating multiple plant hormones

Salt stress is a major environmental factor limiting plant growth and productivity. We recently discovered an important new salt tolerance pathway, where the cell wall leucine-rich repeat extensins LRX3/4/5, the RAPID ALKALINIZATION FACTOR (RALF) peptides RALF22/23 and receptor-like kinase FERONIA (FER) function as a module to simultaneously regulate plant growth and salt stress tolerance. However, the intracellular signaling pathways that are regulated by the extracellular LRX3/4/5-RALF22/23-FER module to coordinate growth, cell wall integrity and salt stress responses are still unknown. Here, we report that the LRX3/4/5-RALF22/23-FER module negatively regulates the levels of jasmonic acid (JA), salicylic acid (SA) and abscisic acid (ABA). Blocking JA pathway rescues the dwarf phenotype of the lrx345 and fer-4 mutants, while disruption of ABA biosynthesis suppresses the salt-hypersensitivity of these mutants. Many salt stress-responsive genes display abnormal expression patterns in the lrx345 and fer-4 mutants, as well as in the wild type plants treated with epigallocatechin gallate (EGCG), an inhibitor of pectin methylesterases, suggesting cell wall integrity as a critical factor that determines the expression pattern of stress-responsive genes. Production of reactive oxygen species (ROS) is constitutively increased in the lrx345 and fer-4 mutants, and inhibition of ROS accumulation suppresses the salt-hypersensitivity of these mutants. Together, our work provides strong evidence that the LRX3/4/5-RALF22/23-FER module controls plant growth and salt stress responses by regulating hormonal homeostasis and ROS accumulation.     

Stoichiometric evolutions of PH3 under high pressure: implication for high-Tc superconducting hydrides

The superconductivity of hydrides under high pressure has attracted a great deal of attention since the recent observation of the superconducting transition at 203 K in strongly compressed H₂S. It has been realized that the stoichiometry of hydrides might change under high pressure, which is crucial in understanding the superconducting mechanism. In this study, PH₃ was studied to understand its superconducting transition and stoichiometry under high pressure using Raman, IR and X-ray diffraction measurements, as well as theoretical calculations. PH₃ is stable below 11.7 GPa and then it starts to dehydrogenate through two dimerization processes at room temperature and pressures up to 25 GPa. Two resulting phosphorus hydrides, P₂H₄ and P₄H₆, were verified experimentally and can be recovered to ambient pressure. Under further compression above 35 GPa, the P₄H₆ directly decomposed into elemental phosphorus. Low temperature can greatly hinder polymerization/decomposition under high pressure and retains P₄H₆ up to at least 205 GPa. The superconductivity transition temperature of P₄H₆ is predicted to be 67 K at 200 GPa, which agrees with the reported result, suggesting that it might be responsible for superconductivity at higher pressures. Our results clearly show that P₂H₄ and P₄H₆ are the only stable P–H compounds between PH₃ and elemental phosphorus, which is helpful for shedding light on the superconducting mechanism.