Search

Fungal disease meets its matchFusariumhead blight (FHB), caused by a fungus, reduces wheat crop yield and introduces toxins into the harvest. From the assembly of the genome ofThinopyrum elongatum, a wild relative of wheat used in breeding programs to improve cultivated wheat, Wanget al.cloned a gene that can address both problems (see the Perspective by Wulff and Jones). The encoded glutathioneS-transferase detoxifies the trichothecene toxin and, when expressed in wheat, confers resistance to FHB.Science, this issue p.eaba5435; see also p.822

In plants, the mechanism for ecological sympatric speciation (SS) is little known. Here, after ruling out the possibility of secondary contact, we show that wild emmer wheat, at the microclimatically divergent microsite of “Evolution Canyon” (EC), Mt. Carmel, Israel, underwent triple SS. Initially, it split following a bottleneck of an ancestral population, and further diversified to three isolated populations driven by disruptive ecological selection. Remarkably, two postzygotically isolated populations (SFS1 and SFS2) sympatrically branched within an area less than 30 m at the tropical hot and dry savannoid south-facing slope (SFS). A series of homozygous chromosomal rearrangements in the SFS1 population caused hybrid sterility with the SFS2 population. We demonstrate that these two populations developed divergent adaptive mechanisms against severe abiotic stresses on the tropical SFS. The SFS2 population evolved very early flowering, while the SFS1 population alternatively evolved a direct tolerance to irradiance by improved ROS scavenging activity that potentially accounts for its evolutionary fate with unstable chromosome status. Moreover, a third prezygotically isolated sympatric population adapted on the abutting temperate, humid, cool, and forested north-facing slope (NFS), separated by 250 m from the SFS wild emmer wheat populations. The NFS population evolved multiple resistant loci to fungal diseases, including powdery mildew and stripe rust. Our study illustrates how plants sympatrically adapt and speciate under disruptive ecological selection of abiotic and biotic stresses.

Genetic variation (rs372883C/T) in the 3'-untranslated region of BTB and CNC homology 1 (BACH1) has been associated with pancreatic ductal adenocarcinoma (PDAC) risk in our previous genome-wide association study; however, the action roles of this genetic variation in PDAC remains unknown. Methods:BACH1 expression was measured by quantitative real-time PCR, Western blot and immunohistochemistry. The effects of BACH1 on cell proliferation and sensitivity to gemcitabine were examined by alteration of BACH1 expression in PDAC cells. Angiogenesis was determined in vitro using a human umbilical vein endothelial cell model. Reporter gene assays were conducted to compare the effects of microRNA-1257 on rs372883 variation. The associations between rs372883 variants and survival time in patients treated with gemcitabine were estimated by logistic regression. Results: We found substantially lower BACH1 expression in PDAC compared with normal pancreatic tissues and the rs372883T allele had significantly lower BACH1 levels than the rs372883C allele in both tumor and normal tissues. Knockdown of BACH1 expression provoked proliferation of PDAC cells and angiogenesis, which might result from upregulation of hemeoxygenase-1 that evokes oncogenic AKT and ERK signaling. The rs372883T>C change inhibits interaction of BACH1 with microRNA-1257, resulting in increased BACH1 expression. PDAC patients with the rs372883T allele were more resistant to gemcitabine and had shorter survival time compared with those with the rs372883C allele. Conclusion: These results shed light on the mechanism underlying the associations of BACH1 rs372883 variation with risk of developing PDAC and differential gemcitabine sensitivity in patients.

The risk of propagation of infectious diseases such as avian influenza and COVID-19 is generally controlled or reduced by quarantine measures. Considering this situation, a network-based SIQS (susceptible-infected-quarantined-susceptible) infectious disease model with nonmonotone incidence rate is established and analyzed in this paper. The psychological impact of the transmission of certain diseases in heterogeneous networks at high levels of infection may be characterized by the related nonmonotone incidence rate. The expressions of the basic reproduction number and equilibria of the model are determined analytically. We demonstrate in detail the uniform persistence of system and the global asymptotic stability of the disease-free equilibrium. The global attractivity of the unique endemic equilibrium is discussed by using monotone iteration technique. We obtain that the endemic equilibrium is globally asymptotically stable under certain conditions by constructing appropriate Lyapunov function. In addition, numerical simulations are performed to indicate the theoretical results.

Measurements on density and viscosity at T = (293.15, 298.15, 303.15, 308.15 313.15, 318.15, 323.15, 328.15, and 333.15) K and the pressure P = 0.1 MPa for binary mixtures of n-dodecane or methylcyclohexane with 1-heptanol or cyclohexylmethanol have been carried out over the whole composition range. Densities were measured with a vibrating-tube densimeter. Viscosities were determined by an automatic microviscometer based on the rolling-ball principle. The excess molar volumes (VmE) and viscosity deviations (Δη) were calculated with experimental data and fitted to the Redlich–Kister equation. The results of these excess or deviation functions are explained by molecular interactions and structural effects. Freezing points were measured with a differential scanning calorimeter. The fundamental data, VmE and Δη can be used to study the nature of mixing behaviors between new hydrocarbon fuels.

Although zinc homeostasis has been demonstrated to play a role in myocardial ischemia/reperfusion (I/R) injury, the roles of zinc transporters that are critical for zinc homeostasis in I/R injury are poorly understood. The purpose of this study was to test if Zip2, an important zinc importer, plays a role in I/R injury in mouse hearts and explore the mechanism by which Zip2 expression is regulated. Zip2 expression was increased at reperfusion in in vivo mouse hearts, an effect that was abolished by ZnCl2, indicating Zip2's attempt to compensate for zinc loss at reperfusion. Further studies showed that upregulation of Zip2 expression was reversed by either pharmacological or genetic inhibition of signal transducers and activators of transcription 3 (STAT3), whereas STAT3 overexpression increased Zip2 expression, indicating that STAT3 accounts for Zip2 upregulation. In support, reperfusion enhanced STAT3 phosphorylation (Tyr705), which was blocked by ZnCl2, implying that STAT3 is activated in response to zinc loss. To determine the role of Zip2 in I/R injury, we assessed I/R injury by genetically disrupting Zip2 expression. Knockout of Zip2 genes (Zip2+/- and Zip2-/-) exacerbated I/R injury by increasing infarct size as well as the serum LDH, troponin I (cTnI), and CK-MB activities. In contrast, delivery of Zip2 genes reduced I/R injury. Delivery of STAT3 genes increased STAT3 phosphorylation and reduced I/R injury. However, delivery of the dominant negative STAT3 mutant did not reduce I/R injury. Moreover, delivery of STAT3 genes failed to reduce I/R injury in Zip2-/- mice. Zip2 upregulated upon reperfusion via STAT3 is cardioprotective and this upregulation may serve as an important intrinsic protective mechanism by which the heart is resistant to I/R injury. The factors involved in the zinc homeostasis (zinc and Zip2) are responsible STAT3 activation and its subsequent cardioprotective action.

Most diseases have multiple pathogenic strains, which may impose difficulty in combatting the disease and lead to rich dynamics. However, their dynamical properties are not well understood. For this purpose, we formulate and analyze a two-strain SIS epidemic model with a competing mechanism and general infection force on complex networks. We derive the basic reproduction number and introduce the invasion reproduction numbers for each strain. We demonstrate that if R 0 1 , the disease-free equilibrium is globally asymptotically stable, i.e., the disease will die out. If R 0 > 1 , the conditions of the existence and global asymptotical stability of dominant equilibria are further studied. The persistence of the system is also addressed. Numerical simulations are given to illustrate the theoretical results.

A non-intrusive, in-situ detection technique for combustion intermediates in flame environments yields highly resolved spectra that are largely insensitive to molecular vibrations and thus temperature. The technique is based on laser photoionization of target compounds via Rydberg states, followed by detection of the laser-induced plasma with microwave radiation. The feasibility of this approach is tested on methyl radicals that are detected in methane, propane, and hexane fuel-rich flames. The methyl radicals are prepared in the 3s Rydberg state using photoexcitation at 216.4 nm. Using tunable VIS/IR radiation, the molecules are promoted from 3s to the 3pxy and 3pz Rydberg states. Photoionization out of the 3p states with 355 nm photons results in a small-volume plasma that is detected by microwave backscattering. The previously unobserved 3pxy state is found to have a binding energy of 2.57 eV.

Density functional theory (DFT) is widely applied in calculations of molecules and materials. Yet, it suffers from a well-known over-emphasis on charge delocalization arising from self-interaction error that destabilizes localized states. Here, using the symmetric diamine N,N′-dimethylpiperazine as a model, we have experimentally determined the relative energy of a state with positive charge localized on one of the two nitrogen atoms, and a state with positive charge delocalized over both nitrogen atoms. The charge-localized state was found to be 0.33 (0.04) eV higher in energy than the charge-delocalized state. This provides an important test of theoretical approaches to electronic structure calculations. Calculations with all DFT functionals commonly used today, including hybrid functionals with exact exchange, fail to predict a stable charge-localized state. However, the application of an explicit self-interaction correction to a semi-local functional identifies both states and gives relative energy in excellent agreement with both experiment and CCSD(T) calculations., Density functional theory is widely used throughout the chemical sciences, but suffers from over-emphasis on charge delocalisation. Here, the authors experimentally probe the energies of two states of a diamine cation and show how a self-interaction correction allows for the accurate prediction of both states.

Three ionization centers make 1,3,5-trimethyl-1,3,5-triazacyclohexane (TMTAC) an interesting model system to study intramolecular charge transfer (CT). Because the molecule assumes a Cs symmetric, axial–equatorial–equatorial (aee) conformation in the ground state, there are two distinct types of the nitrogen atoms. We discovered that either nitrogen atom can be ionized independently so that two molecular cations exist with different (localized) charge distributions in the Franck–Condon region. The initially localized charge can delocalize via CT, provided the molecule acquires a suitable structural geometry. These proper structures are all found to have a common structural motif that supports CT via through-space-interaction. The structural dynamics and the CT process in Rydberg-excited TMTAC, where the molecular ion core closely resembles the ion, were probed by time-resolved Rydberg fingerprint spectroscopy. When TMTAC is excited at 230 nm to the Franck–Condon region of the 3s Rydberg state, the two types of nitrogen atom Rydberg chromophores give rise to distinct binding energy peaks. The sequential molecular responses that follow the Rydberg excitation manifest themselves as time-dependent changes of the binding energy and are observed by ionization at 404 nm. A fast transition with 103 fs time constant was attributed to a motion that leads to a local minimum of the charge-localized state on the Rydberg potential energy surface. Because a large amount of energy is deposited into the vibrational manifolds, the molecule continues to sample the potential energy surface and eventually reaches a dynamic equilibrium between charge-localized and charge-delocalized states. The forward and backward time constants were determined to be 1.02 ps and 4.09 ps, respectively. The binding energy spectrum also reveals the existence of an equilibrium among several charge-delocalized states. Quantum chemical calculations were carried out to find the stable minima of the ground state and the ion state. The binding energies of the Franck–Condon structures and the relaxed ion structures were calculated using the Perdew–Zunger self-interaction corrected DFT (PZ-SIC) method to assign the spectra at time zero and at equilibrium, respectively.

Plant epidermis serves important functions in shoot growth, plant defense and lipid metabolism, though mechanisms of related transcriptional regulation are largely unknown. Here, we identified cis-elements specific to shoot epidermis expression by dissecting the promoter of Triticum aestivum lipid transfer protein 1 (TaLTP1). A preliminary promoter deletion analysis revealed that a truncated fragment within 400 bp upstream from the translation start site was sufficient to confer conserved epidermis-specific expression in transgenic Brachypodium distachyon and Arabidopsis thaliana. Further, deletion or mutation of a GC(N4)GGCC motif at position &ndash, 380 bp caused a loss of expression in pavement cells. With an electrophoretic mobility shift assay (EMSA) and transgenic reporter assay, we found that a light-responsive CcATC motif at position &ndash, 268 bp was also involved in regulating pavement cell-specific expression that is evolutionary conserved. Moreover, expression specific to leaf trichome cells was found to be independently regulated by a CCaacAt motif at position -303 bp.

This paper studies the problem of liquid tank stability control on account of the interaction between liquid sloshing and vehicle in emergency obstacle or turning. The dynamic fluid sloshing model within the tank is modelled using governing equations with potential flow theory, combined with the rigid model of semi-trailer; the liquid sloshing model is integrated into the vehicle model. We compare the stability influence of tank with the same mass of liquid cargo and solid cargo in fishhook. With this unsteady state factor, we designed the optimal control strategy and co-simulation in Matlab/Simulink and TruckSim. Simulation results show that the proposed control approach is effective in rollover prevention of liquid tank under transverse excitation.

Motivated by recent progress in the application of time-resolved photoelectron spectroscopy (TRPES) to molecular Rydberg states, we report herein a detailed assessment of the performance of the second-order algebraic diagrammatic construction (ADC(2)) method in the simulation of their TRPES spectra. As the test case, we employ the tertiary aliphatic amine N-methylmorpholine (NMM), which is notable for the fact that the signal of its 3s state exhibits long-lived oscillations along the electron binding energy axis. The relaxation process of photoexcited NMM is simulated via the Born-Oppenheimer molecular dynamics method, and the resulting TRPES spectrum is generated on the basis of ionization energies and approximate Dyson orbital norms calculated with the continuum orbital technique. On the whole, the simulated TRPES spectrum achieves satisfactory agreement with experiment, which suggests that the ADC(2) method provides a realistic description of the potential energy surfaces of the relevant excited and ionized states. In particular, the simulations reproduce the fine oscillatory structure of the signal of the 3s state, and provide evidence to the effect that it results from a coherent vibrational wavepacket evolving along the deformation modes of the six-membered ring. However, it is found that ADC(2) underestimates electron binding energies by up to a few tenths of an electronvolt. The case of NMM demonstrates the usefulness of ADC(2) as a tool to aid the interpretation of the TRPES spectra of large organic molecules.

The above article, published online on 11 December 2018 in Wiley Online Library (https://doi.org/10.1002/cbin.11080), has been withdrawn by agreement with the journal Editor, Sergio Schenkman, and John WileySons Ltd. The withdrawal has been agreed because the authors have not provided a signed Copyright Transfer Agreement.

BACKGROUND Although it is well known that remifentanil (Rem) elicits cardiac protection against ischemia/reperfusion (I/R) injury, the underlying mechanism remains unclear. This study tested if Rem can protect the heart from I/R injury by inhibiting endoplasmic reticulum (ER) stress through the maintenance of zinc (Zn) homeostasis. METHODS Isolated rat hearts were subjected to 30 minutes of regional ischemia followed by 2 hours of reperfusion. Rem was given by 3 consecutive 5-minute infusions, and each infusion was followed by a 5-minute drug-free perfusion before ischemia. Total Zn concentrations in cardiac tissue, cardiac function, infarct size, and apoptosis were assessed. H9c2 cells were subjected to 6 hours of hypoxia and 2 hours of reoxygenation (hypoxia/reoxygenation [H/R]), and Rem was given for 30 minutes before hypoxia. Metal-responsive transcription factor 1 (MTF1) overexpression plasmids were transfected into H9c2 cells 48 hours before hypoxia. Intracellular Zn level, cell viability, and mitochondrial injury parameters were evaluated. A Zn chelator N,N,N',N'-tetrakis-(2-pyridylmethyl) ethylenediamine (TPEN) or an ER stress activator thapsigargin was administrated during in vitro and ex vivo studies. The regulatory molecules related to Zn homeostasis and ER stress in cardiac tissue, and cardiomyocytes were analyzed by Western blotting. RESULTS Rem caused significant reversion of Zn loss from the heart (Rem + I/R versus I/R, 9.43 ± 0.55 vs 7.53 ± 1.18; P < .05) by suppressing the expression of MTF1 and Zn transporter 1 (ZnT1). The inhibited expression of ER stress markers after Rem preconditioning was abolished by TPEN. Rem preconditioning improved the cardiac function accompanied by the reduction of infarct size (Rem + I/R versus I/R, 21% ± 4% vs 40% ± 6%; P < .05). The protective effects of Rem could be reserved by TPEN and thapsigargin. Similar effects were observed in H9c2 cells exposed to H/R. In addition, MTF1 overexpression blocked the inhibitory effects of Rem on ZnT1 expression and ER stress at reoxygenation. Rem attenuated the collapse of mitochondrial membrane potential (ΔΨm) and the generation of mitochondrial reactive oxygen species by inhibiting ER stress via cardiac Zn restoration (Rem + H/R versus H/R, 79.57% ± 10.62% vs 58.27% ± 4.32%; P < .05). CONCLUSIONS Rem maintains Zn homeostasis at reperfusion by inhibiting MTF1 and ZnT1 expression, leading to the attenuation of ER stress and cardiac injury. Our findings provide a promising therapeutic approach for managing acute myocardial I/R injury.

Cu particles decorated carbon composite microspheres (CCMs) with a unique sesame ball structure have been prepared by combining the mass-producible spray drying technique with calcinations. The conventional cuprammonium cellulose complex solution obtained by dissolving cellulose in a cuprammonia solution has been applied as raw materials for the preparation of Cu(NH3)42+/cellulose complex microspheres via a spray drying process. The resulted Cu(NH3)42+/cellulose complex microspheres are then transformed into the Cu particles homogeneously decorated porous carbon spheres in situ by calcinations at 450 or 550 °C. The coordination effect between the Cu(NH3)42+ species and the hydroxyl groups of the cellulose macromolecules has been exploited for directing the dispersion of the Cu particles in the resultant composite CCMs. The antimicrobial effects of the CCMs are evaluated by determining the minimum growth inhibitory concentrations using Staphylococcus aureus and Escherichia coli as representatives, respecti...

Long-term exposure to airborne PM2.5 is associated with increased lung cancer risk but the underlying mechanism remains unclear. We characterized global microRNA and mRNA expression in human bronchial epithelial cells exposed to PM2.5 organic extract and integrally analyzed microRNA-mRNA interactions. Foci formation and xenograft tumorigenesis in mice with NIH3T3 cells expressing genes targeted by microRNAs were performed to explore the oncogenic potential of these genes. We also detected plasma levels of candidate microRNAs in subjects exposed to different levels of air PM2.5 and examined the aberrant expression of genes targeted by these microRNAs in human lung cancer. Under our experimental conditions, treatment of cells with PM2.5 extract resulted in downregulation of 138 microRNAs and aberrant expression of 13 mRNAs (11 upregulation and 2 downregulation). In silico and biochemical analyses suggested SLC30A1, SERPINB2 and AKR1C1, among the upregulated genes, as target for miR-182 and miR-185, respectively. Ectopic expression of each of these genes significantly enhanced foci formation in NIH3T3 cells. Following subcutaneous injection of these cells into nude mice, fibrosarcoma were formed from SLC30A1- or SERPINB2-expressing cells. Reduced plasma levels of miR-182 were detected in subjects exposed to high level of PM2.5 than in those exposed to low level of PM2.5 (P = 0.043). Similar results were seen for miR-185 although the difference was not statistically significant (P = 0.328). Increased expressions of SLC30A1, SERPINB2 and AKR1C1 were detected in human lung cancer. These results suggest that modulation of miR-182 and miR-185 and their target genes may contribute to lung carcinogenesis attributable to PM2.5 exposure.

Seed reserve utilization is an important characteristic of seed quality. In this study, the rice varieties Jiucaiqing (Oryza sativa ssp. japonica) and IR26 (Oryza sativa ssp. indica) and their recombinant inbred lines were used to determine the physiological and genetic control of seed reserve utilization during the early seedling growth. Seedling dry weight and weight of mobilized seed reserve increased with seed germination, while seed reserve utilization efficiency decreased after the first rise. The early seedling growth is firstly determined by the mobilization of storage reserve followed by the conversion efficiency of utilized seed reserve into seedling tissues. The major soluble sugars in grains were fructose and glucose, while fructose in shoots and roots. Glucose content in grains and fructose in shoots and roots slightly decreased after the first rise with seed germination, while fructose content in grains increased and sucrose content in grains, shoots, and roots changed slightly. Seed reserve utilization was significantly and positively correlated with sugar contents. Amylase activity significantly associated with seed reserve utilization increased with seed germination, while there was a slight change in sucrose synthase activity. Each of the three α-amylase (OsAmy3B, OsAmy3C, and OsAmy3E) and sucrose synthase (OsSus2, OsSus3, and OsSus4) genes might be involved in seed reserve utilization. Two and seven quantitative trait loci (QTL) were identified for amylase and sucrose synthase activity, respectively, in which four were novel QTLs. The identified amylase and sucrose synthase genes/QTLs might be applicable to improve seed reserve utilization during the early seedling growth in rice by the transgenic and marker-assisted selection approaches.

We have explored the ultrafast molecular structural dynamics associated with charge transfer in N,N,N',N'-tetramethylethylenediamine using Rydberg fingerprint spectroscopy in conjunction with self-interaction corrected density functional theory. Excitation at 239 nm prepares the molecule in the Franck-Condon region of the 3s state with the charge localized on one of the two amine groups. As seen from the time-dependent Rydberg electron binding energies, the pathway of the rapidly ensuing dynamics leads through several structurally distinct conformers with various degrees of charge localization before reaching the fully charge-delocalized structure on a picosecond time scale. At several steps along the reaction path, the transient structures are identified through a comparison of the spectroscopically observed binding energies with computed values. The molecular structure is seen to evolve dynamically from an initially folded conformer to the stretched form that supports charge delocalization before an equilibrium sets in with forward and backward time constants of 1.19 (0.14) and 2.61 (0.31) ps, respectively. A coherent wavepacket motion in the charge-localized state with a period of 270 (17) fs and damping of 430 (260) fs is observed and tentatively assigned to the nitrogen umbrella motion. The damping time constant indicates the rate of the energy flow into other vibrations that are not activated by the optical excitation.

A novel control strategy of permanent magnet synchronous motor (PMSM) drive systems is proposed. Based on radial basis function neural network (RBFNN) and direct model reference adaptive control (MRAC), the grid-side controller is designed to regulate output direct current (DC) bus voltage. The coordination control combined sliding model control (SMC) based on signal and port-controlled Hamiltonian (PCH) control based on energy is used to motor-side and achieves the fast speed tracking control and the real-time energy optimization. The controllers based on regenerative braking ensure that the motor can run in four quadrant, energy is bidirectional flow, and the DC bus voltage is controllable. The simulation results demonstrate the validity of the strategy.

A novel four quadrant operation control strategy of permanent magnet synchronous motor (PMSM) drive systems is proposed. In order to regulate precisely output direct current (DC) bus voltage and achieve the control of unity power factor, the exponential functional-based sliding mode reaching law (ESMRL), which adapts to the variations of the grid-side inverter and sliding mode surfaces, is developed. The mathematical model of PMSM based on port-controlled Hamiltonian (PCH) is established according to the energy-balancing point of view. On the basis of energy optimization and operation in four-quadrant, the PCH controller using energy-shaping and passivity-based control is applied in motor-side inverter. The controllers proposed ensure that the motor can run in four-quadrant, energy is bidirectional flow, the DC bus voltage is controllable, the power factor is near one and energy consumption is smaller. The simulation results authenticate the validity of the presented control algorithms.

Genome-wide association studies (GWAS) have consistently identified PLCE1 as esophageal squamous cell carcinoma (ESCC) susceptibility gene; however, the functional role of PLCE1 variants remains to be verified. In this study, we performed fine mapping of the PLCE1 region using our previous ESCC GWAS data and identified 33 additional risk variants in this susceptibility locus. Here, we report the functional characterization of a four-nucleotide insertion/deletion variation (rs71031566 C----/CATTT) in PLCE1 that was associated with risk of developing ESCC. We demonstrate for the first time that rs71031566[CATTT] insertion creates a silencer element, repressing PLCE1 transcription via long-range interaction with PLCE1 promoter mediated by OCT-2 binding. PLCE1 is down-regulated in majority of clinical ESCC samples and overexpression of PLCE1 in ESCC cells suppresses cell growth in vitro and in vivo, suggesting a tumor suppressor role of this gene. Therefore, repression of PLCE1 transcription may be the underlying mechanism for the rs71031566[CATTT] variant to be susceptible to ESCC.

A series of 3-phenyl benzo[d][1,2,3]triazin-4(3H)-one derivatives were synthesized through the condensation of phenol E and alkyl (alkenyl, alkynyl) chlorides (bromides, iodide) or alkyl chloroacetates or N-alkyl chloroacetamides using K2CO3 as the acid acceptor in N,N-dimethylformamide. Phenol E was prepared from starting material, 5-amino-2-chloro-4-fluorophenyl ethyl carbonate, in four steps involving in amidation, reduction, diazotization, and deprotecting-group reaction. The herbicidal activities of the title compounds were tested against two dicotyledonous plants and two monocotyledonous plants, in which some of them exhibited high herbicidal activities against two dicotyledonous plants in preemergence and postemergence treatments. Moreover, when the dosage was decreased to 180 and 90 g/ha, compounds F1, F8, and F9 showed highly selective inhibitory activities against amaranth pigweed, alfalfa, asteraceae, field sowthistle, morning glory, purslane, and velvetleaf in postemergence treatment but had no herbicidal efficacy on rape except F1, suggesting that it be possible to find a kind of herbicides to inhibit dicotyledonous weeds in the field of dicotyledonous crops with the same genus as aforementioned weeds.

Iron bioavailability is crucial for mitochondrial metabolism and biosynthesis. Dysregulation of cellular iron homeostasis affects multiple aspects of mitochondrial physiology and cellular processes. However, the intracellular iron trafficking pathway in Candida albicans remains unclear. In this study, we characterized the Mrs4-Ccc1-Smf3 pathway, and demonstrated its important role in maintaining cellular iron levels. Double deletion of vacuolar iron exporter SMF3 and mitochondrial iron transporter MRS4 further elevated cellular iron levels in comparison with the single MRS4 deletion. However, deletion of vacuolar iron importer CCC1 in the mrs4delta/delta mutant restored cellular iron homeostasis to normal wild-type levels, and also normalized most of the defective phenotypes in response to various environmental stresses. Our results also suggested that both Mrs4 and Cccl contributed to the maintenance of mitochondrial function. The mrs4delta/delta and mrs4delta/deltasmf3delta/delta mutants exhibited an obvious decrease in aconitase activities and mitochondrial membrane potential, whereas deletion of CCC1 in the mrs4delta/delta mutant effectively rescued these defects. Furthermore, we also found that the Mrs4-Ccc1-Smf3 pathway was indispensable for cell-wall stability, antifungal drug tolerance, filamentous growth and virulence, supporting the novel viewpoint that mitochondria might be the promising target for better antifungal therapies. Interestingly, the addition of exogenous iron failed to rescue the defects on non-fermentable carbon sources or hyphae-inducing medium, indicating that the defects in mitochondrial respiration and filamentous development might result from the disturbance of cellular iron homeostasis rather than environmental iron deprivation. Taken together, our results propose the Mrs4-Ccc1-Smf3 pathway as a potentially attractive target for antifungal drug development.

A convenient base-mediated strategy to synthesize 3-aryol-4-methyl (or benzyl)-2-methylthio furans 2 (trisubstituted furans) has been developed through the domino coupling/annulations between available α-oxo ketene dithioacetals 1 and propargyl alcohols. In this strategy, these types of bases play an important role in driving the domino coupling reaction of propargyl alcohols and further intramolecular annulations to realize the target compounds. The possible mechanism for the formation of the various products is believed to involve the generation of allenes 7, followed by intramolecular annulations.

Two nitrogen atoms and a flexible carbon skeleton make N,N,N′,N′-tetramethylethylenediamine (TMEDA) an important model system to study the interplay of conformeric motions and charge delocalization. Ionization of one of the nitrogen atoms generates a localized charge that may (partially) transfer to the other nitrogen. The structural motions, conformation dependent electron lone pair interaction and charge transfer in Rydberg-excited TMEDA, where the molecular ion core closely resembles the ion, were probed by time-resolved Rydberg fingerprint spectroscopy. Excitation to the 3p Rydberg level with a 209 nm laser pulse initially created a charge-localized ion core. Rapid internal conversion to the 3s Rydberg state yielded a multitude of conformational structures, in particular structures that are close to the folded GG′G+ and GGG′+ (see text for label definitions) core structures (235 fs), and structures that are close to the extended TTT+ core structure (557 fs). The initial excitation and the internal conversion deposit about 1.89 eV of energy into the vibrational manifold, enabling a fast equilibrium between the folded and the extended structures. The forward and backward time constants were determined to be 490 fs and 621 fs, respectively. With the molecule highly vibrationally excited, the decay to 3s proceeds with a 6.77 ps time constant. Density functional theory (DFT) and ab initio calculations show evidence of strong lone pair interaction and charge delocalization in the equilibrium conformers. Importantly, DFT with self-interaction correction properly describes the binding energy of the Rydberg electron and provides excellent agreement with the experimental results.

Two identical ionization centers, one on each nitrogen atom, make N,N′-dimethylpiperazine an important model to explore how the transfer of a (partial) charge is linked to the structural deformations of the molecular skeleton. Time-resolved photoelectron spectroscopy uncovered that upon excitation to the 3p Rydberg level at 207 nm only one of the initially symmetry-equivalent nitrogen atoms acquires the charge, creating an asymmetric molecular structure with a localized charge. Rapid internal conversion to 3s leads to a multitude of conformeric structures with the charge localized on one nitrogen atom (230 fs time constant) and a rigid structure with the charge delocalized over both nitrogen atoms (480 fs time constant). Structural motions continue while the molecule samples the 3s potential energy landscape, leading to an equilibrium between charge-localized and charge-delocalized conformeric structures that is approached with a 2.65 ps time constant.

Iron is an essential element required for most organisms. The high-affinity iron-uptake systems in the opportunistic pathogen Candida albicans are activated under iron-limited conditions and are also required for virulence. Here one component of high-affinity iron-uptake systems, the multicopper oxidase (MCO) genes, was characterized. We examined the expression of five MCO genes and demonstrated that CaFET3 and CaFET34 were the major MCO genes in response to iron deficiency. Complementation of the Saccharomyces cerevisiae fet3Δ mutant showed that CaFET34 could effectively rescue the growth phenotype in iron-limited medium. Deletion of CaFET33 and CaFET34 in C. albicans decreased cellular iron content and iron acquisition during iron starvation. However, the fet33Δ/Δ and fet34Δ/Δ mutants exhibited no obvious growth defect in solid iron-limited medium while the fet34Δ/Δ mutant showed a slight growth defect in liquid medium. Further analysis shows that other members of the five MCO genes, especially CaFET3, would compensate for the absence of CaFET33 and CaFET34. Furthermore, for the first time, we provide evidence that CaFET34 is implicated in hyphal development in an iron-independent manner and is required for C. albicans virulence in a mouse model of systemic infection. Together, our results not only expand our understanding about the expression of the MCO genes in C. albicans, but also provide a novel insight into the role of CaFET34 in iron metabolism, hyphal development and virulence.

Summary Background The activation of nuclear factor-kappa B (NF-κB) and NLRP3 inflammasome is involved in neuroinflammation, which is closely linked to Alzheimer's disease (AD). In vivo and in vitro studies have suggested that artemisinin shows antiinflammatory effects in inflammation-related diseases. However, the impacts of artemisinin on AD have not been investigated. Aims In this study, 5-month-old APPswe/PS1dE9 transgenic mice were treated daily with 40 mg/kg artemisinin for 30 days by intraperitoneal injection to evaluate the effects of artemisinin on AD. Results We found that artemisinin treatment (1) decreased neuritic plaque burden; (2) did not alter Aβ transport across the blood–brain barrier; (3) regulated APP processing via inhibiting β-secretase activity; (4) inhibited NF-κB activity and NALP3 inflammasome activation in APPswe/PS1dE9 double transgenic mice. Conclusions The in vivo study clearly demonstrates that artemisinin has protective effects on AD pathology due to its effects on suppressing NF-κB activity and NALP3 inflammasome activation. Our study suggests that targeting NF-κB activity and NALP3 inflammasome activation offers a valuable intervention for AD.

Calcium channels and pumps play important roles in morphogenesis, stress response and virulence in Candida albicans. We hypothesised that verapamil, a potent calcium channel blocker, may display an inhibitory effect on C. albicans biofilms. To test this hypothesis, the in vitro activity of verapamil was evaluated alone and in combination with fluconazole or tunicamycin against C. albicans biofilms using a 96-well microtitre plate model. As expected, verapamil exerted inhibitory activity against C. albicans biofilms. The combinations of verapamil/fluconazole and verapamil/tunicamycin yielded synergistic effects on biofilm formation and on pre-formed biofilms. Furthermore, verapamil alone or in combination with fluconazole or tunicamycin led to a significant decrease in the transcription level of ALS3, essential for biofilm development. Therefore, verapamil may be a potential agent to enhance the effect of antifungal drugs against C. albicans biofilms.

Background & Aims A common variant in the solute carrier family 39 member 6 gene ( SLC39A6 ) has been associated with survival times of patients with esophageal squamous cell carcinoma (ESCC). We investigated the function of SLC39A6 and ways in which this variant affects tumor progression by studying ESCC samples and cell lines. Methods SLC39A6 was expressed or knocked down by expression of short hairpin RNAs in ESCC cells (KYSE30 and KYSE450) and HeLa cells using lentiviral vectors; we analyzed effects on proliferation, colony formation, migration, and invasion in vitro. Cells were grown as xenograft tumors in nude mice and tumor volume and metastases were quantified; tumors were collected and analyzed histologically. Cells were also analyzed for levels of intracellular zinc and messenger RNA (mRNA) expression patterns. We obtained ESCC and adjacent normal esophageal tissues from 94 patients who underwent esophagectomy in China from 2010 through 2014. Survival times of patients were measured from the date of diagnosis to the date of last follow-up or death. We sequenced mRNAs and compared levels between tumor and non-tumor tissues using the Wilcox rank-sum test. Total proteins in cell lines or tissue samples were measured by immunoblotting. We searched publicly available databases for variants of SLC39A6 in human tumor and non-tumor tissues. Results Knockdown of SLC39A6 reduced proliferation of ESCC cells in culture and metastasis of xenograft tumors in mice. Cells that overexpressed SLC39A6 had significant increases in intracellular levels of zinc and were more invasive in assays, activating phosphatidylinositol 3-kinase signaling to AKT serine/threonine kinase 1 and mitogen-activated protein kinase 1. Cells that overexpressed SLC39A6 had increased expression of mRNAs and proteins associated with metastasis, such as matrix metalloproteinase (MMP) 1, MMP3, MYC, and snail family transcriptional repressor 2 (SNAI2 or SLUG). Levels of MMP1, MMP3, MYC, and SLUG mRNAs correlated with levels of SLC39A6 mRNA in ESCC samples from patients. ESCC tissues had increased levels of SLC39A6 mRNA compared with non-tumor tissues; the increase correlated with tumor metastasis to lymph node and reduced patient survival time. Conclusions In an analysis of ESCC samples and cell lines, we associated increased expression of SLC39A6 with tumor invasiveness, intracellular level of zinc, and patient survival time. ESCC cell lines that overexpress SLC39A6 up-regulate expression MMP1, MMP3, MYC, and SLUG and form metastatic xenograft tumors in mice. Up-regulation of SLC39A6 might be used to determine prognoses of patients with ESCC or as a therapeutic target.

Iron is an essential nutrient required for the growth and metabolism in Candida albicans. Here, we for the first time identified Mrs4 as a new member of mitochondrial carrier family in C. albicans. Our experiments revealed that C. albicans Mrs4 (CaMrs4) is localized to the mitochondria and required for mitochondrial morphology. We found that CaMrs4 is required for cell growth, and the mrs4Δ/Δ mutant showed a more severe growth defect in iron deficiency. Deletion of MRS4 affected cellular iron content by altering the expression of iron regulon genes in C. albicans, such as AFT2, SMF3, FTR1 and ISU1. Candida albicans Aft2 factor functions as a negative regulator of MRS4 expression through the CACCC Aft-type sequence in a gene dose-dependent fashion. In addition, the mrs4Δ/Δ mutant exhibited hypersensitivity to oxidants and most metal ions, but decreased sensitivity to cobalt. Exogenous iron could suppress the sensitivity of the mrs4Δ/Δ mutant to oxidants and most metal ions, suggesting that the role of CaMrs4 is partially mediated by iron availability. Furthermore, deletion of MRS4 resulted in delayed filamentation under tested conditions. Taken together, these findings characterize a new mitochondrial carrier and provide a novel insight into the role of CaMrs4 in mitochondrial function.

We have investigated the adsorption of hydrophobically end-capped poly(ethylene glycol) (HE-PEG) with carbon number (m) in the hydrocarbon end chain ranging from 0 to 16 onto phospholipid membrane by use of quartz crystal microbalance with dissipation (QCM-D), surface plasmon resonance (SPR) and isothermal titration calorimetry (ITC). QCM-D and SPR studies show that the hydrophobic interaction between HE-PEG chains and the lipid membrane increases with the hydrocarbon chain length. At a low HE-PEG concentration, the adsorption cannot induce a vesicle-to-bilayer transition until the carbon number is up to 16. However, at a high HE-PEG concentration, the adsorption results in a vesicle-to-bilayer transition at m > or = 12. ITC measurements demonstrate that enthalpy change (DeltaH) for the mixing of lipid vesicles with HE-PEG chains is too small to be detectable when m is less than 12. However, DeltaH changes from positive to negative as the carbon number increases from 12 to 16, indicating that the HE-PEG insertion increases with its hydrocarbon end-chain length. The present study reveals that the hydrophobic interaction between the lipid membrane and HE-PEG chains as well as the osmotic pressure drive the adsorption and insertion of such polymer chains.

To identify potential mutation of the colony stimulating factor 1 receptor gene (CSF1R) in a large Chinese family affected with hereditary diffuse leukoencephalopathy with spheroids (HDLS) and analyze the genotype-phenotype correlation.The proband was evaluated physically and radiologically to ascertain the HDLS phenotype. Genomic DNA was extracted from peripheral blood samples from family members. The coding region of the CSF1R gene was amplified with PCR and subjected to direct DNA sequencing.There were 9 affected members (5 alive) in this five-generation family (1 member had died during the follow-up). A missense mutation c.2563CA (p.P855T) of the CSF1R gene has been identified in the proband. The same mutation was identified in 3 affected and 1 unaffected members of the family.The family was consistent with autosomal dominant inheritance. CSF1R gene mutation is also a disease-causing mutation in Chinese patients.

Ferric reductases play a central role in iron acquisition and mobilization in C. albicans. This study focuses on stress response strategies exhibited by several ferric reductase genes through function and expression analyses.Northern blot analysis was used to examine ferric reductase genes expression levels in different iron deficiency. We constructed ferric reductase-null mutants by a PCR-based homologous recombination, and examined the effects of gene deletion on cell-surface ferric reductase activity and growth ability under different conditions. Sub-cellular localization of Frpl-GFP fusion was imaged and analyzed by confocal laser scanning fluorescence microscopy.FRE10 was highly expressed at acidic pH, compared to that at alkaline pH, whereas the expression of FRE2 was just the opposite. Deletion of FRE10 resulted in a significant decreased surface reductase activity at acidic pH, with 75.5% down-regulation compared to wild-type levels. The fre2delta/delta mutant showed significantly attenuated growth ability and cell-surface ferric reductase activity at alkaline pH. Sub-cellular localization revealed that the green fluorescence was accumulated in the vacuoles.The expression of both FRE10 and FRE2 is induced in a pH-dependent manner. FRE2 encodes a major cell surface ferric reductase under alkaline pH condition. Frp1 localizes to the vacuole, and might support mobilization and transport of vacuolar ferric iron stores.

To explore the characteristics of cognitive impairment and correlation analysis in patients with chronic renal failure (CRF).The Addenbrooke's cognitive examination revised (ACE-R) scale was used to evaluate the cognitive function for 101 cases of chronic renal failure patients (group CRF) receiving outpatient and inpatient treatments and selected 30 individuals with normal renal function as normal controls (group NC) for cross-sectional analysis. T test, receiver operating characteristic (ROC) curve and other statistical methods were adopted for comparing differences.(1) Compared with group NC (83.4 ± 6.5), group CRF (71.9 ± 17.6) showed significantly statistical difference on Addenbrooke's cognitive examination revised (ACE-R) scale scores (P0.01); (2)compared with normal controls, the patients with CRF had significantly statistical difference on the scores of visual spatial ability (11.5 ± 3.2, 14.0 ± 3.0 respectively), language fluency (7.0 ± 2.6, 8.7 ± 1.9) (P0.01) and memory (18.1 ± 7.0, 21.5 ± 3.6 respectively) (P0.05); (3) the cognitive function of patients with CRF were significantly positive correlated with glomerular filtration rate (GFR) (r = 0.614, P0.01) and negatively correlated with the duration of illness (r = -0.492, P0.01); (4) From ROC curve and the area under curve (AUC), ACE-R scale (AUC = 0.680) showed a higher sensitivity than mini-mental state examination scale (AUC = 0.576) in assessing cognitive function in patients with CRF (P0.01).(1) Under similar basic conditions of age, level of education and background, CRF patients showed significant damage overall cognitive function, cognitive impairment in visual spatial ability, executive function, long-term memory and logical judgment ability was particularly impaired. Immediate and delayed memory, attention, orientation and language ability also manifested different degrees of decline; (2) the severity of cognitive impairment in patients with CFR was closely related with the level of GFR; (3) the ACE-R scale showed a higher sensitivity than mini-mental state examination scale in assessing cognitive function in patients with CRF.

Hereditary diffuse leukoencephalopathy with neuroaxonal spheroids (HDLS) is a rare autosomal dominant leukoencephalopathy disease, and colony stimulating factor 1 receptor (CSF1R) is the only gene in which mutations are known to cause HDLS. HDLS should be suspected in individuals with progressive neurological decline, characteristic MR imaging findings, and positive family history. This article reviews recent advance in imaging findings, clinical manifestations, genetic counseling and management in HDLS.

Resveratrol, a natural polyphenolic phytochemical, has received considerable attention due to its potential chemopreventive and chemotherapeutic properties. In the present study, we first evaluated the growth-inhibitory effect of resveratrol on HepG2 cells and explored the underlying molecular mechanisms. Resveratrol inhibited proliferation and induced apoptosis in HepG2 cells via activation of caspase-9 and caspase-3, upregulation of the Bax/Bcl-2 ratio and induction of p53 expression. Cell cycle analysis demonstrated that resveratrol arrested cell cycle progression in the G1 and S phase. We further focused on the combination of matrine, a natural component extracted from the traditional Chinese medical herb Sophora flavescens Ait., as a mechanism to potentiate the growth-inhibitory effect of resveratrol on HepG2 cells. Both MTT and colony formation assay results indicated that the combined treatment of resveratrol and matrine exhibited a synergistic antiproliferative effect. In addition, resveratrol-induced apoptosis was significantly enhanced by matrine, which could be attributed to activation of caspase-3 and caspase-9, downregulation of survivin, induction of reactive oxygen species (ROS) generation and disruption of mitochondria membrane potential (Δψm). Our findings suggest that the combination treatment of resveratrol and matrine is a promising novel anticancer strategy for liver cancer; it also provides new insights into the mechanisms of combined therapy.

In this study, one rice population of recombinant inbred lines (RILs) was used to determine the genetic characteristics of seed reserve utilization during the early (day 6), middle (day 10) and late (day 14) germination stages. The seedling dry weight (SDW) and weight of the mobilized seed reserve (WMSR) were increased, while the seed reserve utilization efficiency (SRUE) decreased, during the process of seed germination. The SDW and WMSR were affected by the seed weight, while the SRUE was not affected by the seed weight. A total of twenty unconditional and twenty-one conditional additive QTLs and eight epistatic QTLs were identified at three germination stages, and the more QTLs were expressed at the late germination stage. Among them, twelve additive and three epistatic QTLs for SDW, eight additive and three epistatic QTLs for WMSR and thirteen additive and two epistatic QTLs for SRUE were identified, respectively. The phenotypic variation explained by each additive QTL, epistatic QTL and QTL × development interaction ranged from 6.10 to 23.91%, 1.79 to 6.88% and 0.22 to 2.86%, respectively. Two major additive QTLs qWMSR7.1 and qSRUE4.3 were identified, and each QTL could explain more than 20% of the total phenotypic variance. By comparing the chromosomal positions of these additive QTLs with those previously identified, eleven QTLs might represent novel genes. The best four cross combinations of each trait for the development of RIL populations were selected. The selected RILs and the identified QTLs might be applicable to improve rice seed reserve utilization by the marker-assisted selection approach.

Calcium is a universal messenger that translates diverse environmental stresses and developmental cues into specific cellular and developmental responses. In yeast, Cch1 and Mid1 function as part of a high affinity Ca²⁺ influx system (HACS) that becomes activated rapidly in response to sudden stimuli. Here, we report that Ecm7, a regulator of HACS, plays important roles in calcium homeostasis maintenance, oxidative stress response and hyphal development in Candida albicans. Disruption of ECM7 led to increased sensitivity to calcium-depleted conditions. Flow cytometry analysis revealed that Ecm7 mediated Ca²⁺ influx under high pH shock. Cycloheximide chase experiments further showed that MID1 deletion significantly decreased the stability of Ecm7. We also provided evidences that ecm7Δ/Δ cells were hypersensitive to oxidative stress. ECM7 deletion induced the degradation of Cap1 when exposed to H₂O₂ treatment. Besides, the ecm7Δ/Δ mutant showed a defect in hyphal development, which was accompanied with the decreased expression of hyphal related gene HWP1. Though subsequent experiments revealed that the ecm7Δ/Δ mutant showed similar virulence to the wild-type strain, the ability of invasion and diffusion of the mutant in mouse kidneys decreased. Taken together, Ecm7 plays important roles in the adaptation and pathogenicity of C. albicans.

Morphological transition and iron metabolism are closely relevant to Candida albicans pathogenicity and virulence. In our previous study, we demonstrated that C. albicans Aft2 plays an important role in ferric reductase activity and virulence. Here, we further explored the roles of C. albicans Aft2 in numerous cellular processes. We found that C. albicans Aft2 exhibited an important role in iron metabolism through bi-directional regulation effects on iron-regulon expression. Deletion of AFT2 reduced cellular iron accumulation under iron-deficient conditions. Furthermore, both reactive oxygen species (ROS) generation and superoxide dismutase (SOD) activity were remarkably increased in the aft2Δ/Δ mutant, which were thought to be responsible for the defective responses to oxidative stress. However, we found that over-expression of C. albicans AFT2 under the regulation of the strong PGK1 promoter could not effectively rescue Saccharomyces cerevisiae aft1Δ mutant defects in some cellular processes, such as cell-wall assembly, ion homeostasis and alkaline resistance, suggesting a possibility that C. albicans Aft2 weakened its functional role of regulating some cellular metabolism during the evolutionary process. Interestingly, deletion of AFT2 in C. albicans increased cell surface hydrophobicity, cell flocculation and the ability of adhesion to polystyrene surfaces. In addition, our results also revealed that C. albicans Aft2 played a dual role in regulating hypha-specific genes under solid and liquid hyphal inducing conditions. Deletion of AFT2 caused an impaired invasive growth in solid medium, but an increased filamentous aggregation and growth in liquid conditions. Moreover, iron deficiency and environmental cues induced nuclear import of Aft2, providing additional evidence for the roles of Aft2 in transcriptional regulation.

The calcium gate encoded by CCH1 and MID1 genes is the main channel for external calcium absorption. As one of the important secondary messengers, the elevation of calcium concentration could activate some pathways to take part in various cell processes. In this study, we used CCH1 and MID1 mutant strains and also constructed their complementary strains to study the effect of drug tolerance and virulence of Candida albicans after CCH1 or MID1 deletion. By drug plate sensitivity assay and the broth microdilution method, we compared the changes between different strains. Moreover, we added calcium channel blocker and inhibitors to analyze the effect of calcium concentration on drug action. After the deletion of CCH1 or MID1 gene, the strain exhibited an obvious sensitivity to FLUC and ITRA, and the drug action was regulated by the calcium concentration. In a mouse model of intravenous infection, we found that attenuated virulence of cch1delta/delta or mid1delta/delta strain is specifically due to a loss of CCH1 or MID1 gene.

Endoplasmic reticulum (ER) is crucial for protein folding, glycosylation and secretion in eukaryotic organisms. These important functions are supported by high levels of Ca(2+) in the ER. We have recently identified a putative ER Ca(2+) pump in Candida albicans, called Spf1, which plays key roles in maintenance of cellular Ca(2+) homeostasis, morphogenesis and virulence. In this study, we purified Spf1 and confirmed that it is a P-type ATPase, suggesting its role in maintaining high levels of ER Ca(2+). Disruption of SPF1 caused severe defects in glycosylation of the ER-localized protein Cdc101 and secretory acid phosphatase, and a decrease in expression of SEC61 which encodes an important ER protein. Moreover, the spf1Δ/Δ mutant showed increased sensitivity to cell wall stresses, abnormal cell wall composition, delayed cell wall reconstruction and decreased flocculation and adherence, indicating its defect in cell wall integrity (CWI). We also revealed that disruption of SPF1 has an impact on gene expression related to CWI and morphogenesis. This study provides evidence that Spf1, as a P-type ATPase, is essential for ER functions and consequent CWI, implicating a role of ER Ca(2+) homeostasis in C. albicans physiology.

The maintenance of cellular calcium homeostasis is associated with cellular signalling transduction and the functions of many membrane compartments, especially endoplasmic reticulum (ER) function. ER-localized proteins that serve to maintain ER and cellular calcium homeostasis in Candida albicans are still unclear. In this study, Spf1, the putative C. albicans homologue of the Saccharomyces cerevisiae ER-localized P-type calcium ATPase ScSpf1, was investigated for its roles in cellular calcium homeostasis, hyphal development and virulence. We constructed an Spf1 null mutant which showed decreased vegetative growth rate and hypersensitivity to EGTA, high-level calcium and antifungal drugs. Similar to treatments of ER stress agents, deletion of SPF1 stimulated calcium influx in the presence of FK506, resulting in an increase in cellular calcium contents, and induced expression of the calcium-dependent response elements gene CCH1, which is essential for the cell calcium survival pathway. Moreover, the spf1 null mutant had defects in hyphal development and biofilm formation, and was severely attenuated in virulence. These findings provided phenotypic evidence supporting roles for Spf1 in the maintenance of cellular calcium homeostasis, ER stress responses, hyphal development, biofilm formation and virulence in C. albicans.