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Abiotic and biotic environments influence a myriad of plant-related processes, including growth, development, and the establishment and maintenance of interaction(s) with microbes. As a driver of this signaling between plants and microbes, the role of plant hormones in both surveillance and signaling has emerged as a point of intersection between plant-abiotic and -biotic responses. In the current study, we elucidate a role for NON-RACE-SPECIFIC DISEASE RESISTANCE1 (NDR1) by exploiting effector-triggered immunity (ETI) to define the regulation of plant host immunity in response to both pathogen infection and elevated temperature. We generated time-series RNA sequencing data of WT Col-0, a NDR1 overexpression line, as well as ndr1 and ics1-2 mutant plants under elevated temperature. Not surprisingly, the NDR1-overexpression line showed genotype-specific gene expression changes related to defense response and immune system function. Interestingly, overexpression of NDR1 revealed a role for NDR1 in immune system function; specifically, we describe a mechanism that intersects with Pseudomonas syringae, type-III effector translocation, R-protein signaling complex stabilization, and sustained levels of SA at elevated temperature during ETI. The results described herein support a role for NDR1 in maintaining cell signaling during simultaneous exposure to elevated temperature and avirulent pathogen stressors.One-sentence summaryNDR1 is required for Pst-AvrRpt2 triggered ETI at elevated temperature.

Pattern-triggered immunity and effector-triggered immunity are two primary forms of innate immunity in land plants. The molecular components and connecting nodes of pattern-triggered immunity and effector-triggered immunity are not fully understood. Here, we report that the Arabidopsis calcium-dependent protein kinase CPK3 is a key regulator of both pattern-triggered immunity and effector-triggered immunity. In vitro and in vivo phosphorylation assays, coupled with genetic and cell biology-based analyses, show that actin-depolymerization factor 4 (ADF4) is a physiological substrate of CPK3, and that phosphorylation of ADF4 by CPK3 governs actin cytoskeletal organization associated with pattern-triggered immunity. CPK3 regulates stomatal closure induced by flg22 and is required for resistance to Pst DC3000. Our data further demonstrates that CPK3 is required for resistance to Pst DC3000 carrying the effector AvrPphB. These results suggest that CPK3 is a missing link between cytoskeleton organization, pattern-triggered immunity and effector-triggered immunity., Remodelling of the actin cytoskeleton occurs during plant immune responses to pathogens. Here Lu et al. show that this process requires the calcium-dependent kinase CPK3 which phosphorylates actin depolymerizing factor 4 and is required for both PAMP and effector-triggered immunity in Arabidopsis.

Throughout their life span, plants confront an endless barrage of pathogens and pests. To successfully defend against biotic threats, plants have evolved a complex immune system responsible for surveillance, perception, and the activation of defense. Plant immunity requires multiple signaling processes, the outcome of which vary according to the lifestyle of the invading pathogen(s). In short, these processes require the activation of host perception, the regulation of numerous signaling cascades, and transcriptome reprograming, all of which are highly dynamic in terms of temporal and spatial scales. At the same time, the development of a single immune event is subjective to the development of plant immune system, which is co-regulated by numerous processes, including plant ontogenesis and the host microbiome. In total, insight into each of these processes provides a fuller understanding of the mechanisms that govern plant-pathogen interactions. In this review, we will discuss the "lifecycle" of plant immunity: the development of individual events of defense, including both local and distal processes, as well as the development and regulation of the overall immune system by ontogenesis regulatory genes and environmental microbiota. In total, we will integrate the output of recent discoveries and theories, together with several hypothetical models, to present a dynamic portrait of plant immunity.

We prepared the ternary blends active layer by incorporating a new two-dimensional donor-acceptor (D/A) conjugated polymer (BDTTBO) comprising benzo-dithiophene-thiophene-thiophene-benzo oxadiazole chemical units that has three different conjugated side chains bithiophene (BT), benzothiophene (BzT) and thienothiophene (TT) BDTTBO-BT, BDTTBO-BzT and BDTTBO-TT into poly (benzodithiophene-fluorothienothiophene) (PTB7-TH) and PC71BM as for organic photovoltaics (OPVs). We expected that incorporating these BDTTBO with different side chains into the blend of PTB7-TH and PC71BM not only can broaden the absorption of solar spectrum thereby increasing short-circuit current density but also tune the packing of PTB7-TH and the dispersion of PC71BM. In particular, we found that incorporating 10% of BDTTBO-BT to form the PTB7-TH: BDTTBO-BT: PC71BM ternary blend (active layer) device could improve the power conversion efficiency to 10.4% from 9.0% for the binary blend of PTB7-TH: PC71BM device—a relative increase of 15%. We examined the packing orientations of the PBDTTBO: PTB7-TH:PC71BM ternary blend films using synchrotron two-dimensional grazing-incidence wide-angle X-ray scattering, and found that the incorporation of 10% relatively higher crystallinity PBDTTBO-BT, PBDTTBO-BzT or PBDTTBO-TT not only altered the packing orientation of PTB7-TH substantially but also reduced PC71BM cluster size in the ternary blend system, as compared to that in the case of PTB7-TH with PC71BM binary blend, thereby providing more pathways for electrons and thus enhancing the carrier transport in the ternary blend, as evidenced by the carrier mobility.

NON-RACE-SPECIFIC DISEASE RISISTANCE1 (NDR1) is a key component of plant immune signaling, required for defense against the bacterial pathogen Pseudomonas syringae. Plant stress responses have overlapping molecular, physiological, and cell biology signatures, and given the central role of NDR1 during biotic stress perception and signaling, we hypothesized that NDR1 also functions in abiotic stress responses, including in a role that mediates signaling at the plasma membrane (PM) - cell wall (CW) continuum. Here, we demonstrate that NDR1 is required for the induction of drought stress responses in plants, a role that couples stress signaling in an abscisic acid-dependent manner. We show that NDR1 physically associates with the PM-localized H+-ATPases AHA1, AHA2, and AHA5 and is required for proper regulation of H+-ATPase activity and stomatal guard cell dynamics, providing a mechanistic function of NDR1 during drought responses. In the current study, we demonstrate that NDR1 functions in signaling processes associated with both biotic and abiotic stress response pathways, a function we hypothesize represents NDR1’s role in the maintenance of cellular homeostasis during stress. We propose a role for NDR1 as a core transducer of signaling between cell membrane processes and intercellular stress response activation.

This paper reports two new fluorine-substituted polymer donors (BO2FC8, BO2FEH), with different side-chain architectures, and a new chlorine-substituted small-molecule acceptor (m-ITIC-OR-4Cl) that are capable of simultaneous charge and energy transfer as the binary blend active layer for organic photovoltaics. We first resolved the single-crystal structure of m-ITIC-OR-4Cl and then used simultaneous grazing-incidence wide- and small-angle X-ray scattering to decipher the multi-length-scale structures—such as the shape and size of aggregated domains and molecular orientation—of the blends of BO2FEH and BO2FC8 with m-ITIC-OR-4Cl. The linear side chains of BO2FC8 facilitated its packing and, thus, induced m-ITIC-OR-4Cl to form smaller disc-shaped aggregated domains (thickness: 2.9 nm) than its aggregate domain (thickness: 5.4 nm) in the blend of the branched BO2FEH. That is, the binary blend system of linear-side-chain BO2FC8 with m-ITIC-OR-4Cl featured larger interfacial areas and more pathways for charge transfer and transport, as evidenced by their carrier mobilities. The highest power conversion efficiency (PCE) of 11.0% was that for the BO2FC8:m-ITIC-OR-4Cl device, being consistent with the predicted PCE of 11.2% using machine learning based on random forest algorism; in comparison, the PCE of the BO2FEH:m-ITIC-OR-4Cl device was 6.4%. This study has not only provided insight into the photovoltaic performances of new polymer donor/small-molecule acceptor blends but has also, for the first time, deciphered the hierarchical morphologies—from molecule orientation to nano-domain shape and size—of such blend systems, linking the morphologies to the photovoltaic performances. The use of side-chain architectures suggests an approach for tuning the morphology of the polymer/small-molecule binary blend active layer for use in organic photovoltaics.

We evaluated the efficacy of a recombinant adenovirus that expresses a membrane-truncated respiratory syncytial virus (RSV) fusion protein (Ad-F0ΔTM) in newborns via maternal immunization (MI) of pregnant cotton rats. Intranasal Ad-F0ΔTM immunization was given to pregnant female rats, and MI-newborn rats were then challenged intranasally with RSV. Anti-RSV IgGs were observed in the serum of MI-newborn rats after birth. The pulmonary viral loads in Ad-F0ΔTM vs. control vector, Ad-LacZ, and MI-newborns on day 3 post-challenge were reduced by 4 log 10 /g lung. The neutralizing antibody remained for up to 3 weeks in the serum of MI-newborns, which is when weaning began. Ad-F0ΔTM protected MI-newborns from RSV challenge for 1 week. Vertical-transferred protective antibodies were examined in the breast milk and placenta as well. Finally, anti-RSV immunity was not boosted but was only primed during the next RSV exposure in Ad-F0ΔTM-MI-newborns. Maternal Ad-F0ΔTM immunization provides acute protection against RSV infection in neonates.

Several approaches, including the use of small molecule acceptors, novel polymer structures, and tandem cell structures, have been adopted to prepare polymer solar cells displaying high power conversion efficiencies (PCEs). The application of ternary blends as the active layer for polymer solar cells—for which the absorption spectra can be tuned by varying the composition ratios of components—is another facile approach toward optimizing the PCEs of devices. The selection of suitable ternary blends active layer often relies on intuition and remains a formidable challenge. Here, we adopted a systemic approach of not only using the same donor chemical units in the two donor-acceptor (D/A) conjugated polymers with complementary light absorption (energy band gaps) but also varying the side chains architectures as a means of tuning the packing of these semi-planar conjugated polymers, thereby influencing the carrier transport and optimizing the PCE. We employed linear, branch and mixed linear-and-branch side-chain attached benzooxadiazole (BO) as the acceptor (A) units in poly[benzodithiophene-thiophene-benzooxadiazole] (PBDTTBO) conjugated polymers and monitored their interactions with poly[benzodithiophene-fluorothienothiophene] (PTB7-TH), both of which featured the same benzodithiophene (BDTT) donor (D) units. We found that incorporating a minor amount (10%) of D/A conjugated PBDTTBO with such side chains into the PTB7-TH with a fullerene allowed us to tune the packing of the two polymers and, thereby, enhance the PCEs of corresponding ternary blend devices; the PCE of the ternary blend device incorporating PBDTTBO with two branched-side chains, PTB7-TH, and PC 71 BM increased to 11.4% from 9.0% for the device incorporating only the binary blend of PTB7-TH and PC 71 BM—a relative increase of more than 25%. This approach of using side chain engineering to tune the structure of a minor conjugated polymer and, thus, influence the packing of another major conjugated polymer that features the same donor chemical units appears to be an effective means of preparing highly efficient polymer cells.

The plant cytoskeleton underpins the function of a multitude of cellular mechanisms, including those associated with developmental- and stress-associated signaling processes. In recent years, the actin cytoskeleton has been demonstrated to play a key role in plant immune signaling, including a recent demonstration that pathogens target actin filaments to block plant defense and immunity. Herein, we quantified spatial changes in host actin filament organization after infection with Pseudomonas syringae pv. tomato DC3000 (Pst DC3000), demonstrating that the type-III effector HopG1 is required for pathogen-induced changes to actin filament architecture and host disease symptom development during infection. Using a suite of pathogen effector deletion constructs, coupled with high-resolution microscopy, we found that deletion of hopG1 from Pst DC3000 resulted in a reduction in actin bundling and a concomitant increase in the density of filament arrays in Arabidopsis, both of which correlate with host disease symptom development. As a mechanism underpinning this activity, we further show that the HopG1 effector interacts with an Arabidopsis mitochondrial-localized kinesin motor protein. Kinesin mutant plants show reduced disease symptoms after pathogen infection, which can be complemented by actin-modifying agents. In total, our results support a model in which HopG1 induces changes in the organization of the actin cytoskeleton as part of its virulence function in promoting disease symptom development.

Enterovirus 71 (EV71) is a major cause of hand, foot and mouth disease (HFMD). The current EV71 propagating in Vero (EV-V) or sub-passaged in RD (EV-R) cells was used as a pathogen. Interestingly, EV-R exhibited differential virulence; challenging human scavenger receptor class B2-expressing (hSCARB2-Tg) mice with EV71 revealed that EV-V was more virulent than EV-R: 100% of mice that received lethal amounts of EV-V died, while all the mice that received EV-R survived. Severe pathogenesis correlated with viral burdens and proinflammatory cytokine levels were observed in EV-V-challenged mice, but controversy in EV-R-challenged mice. Consensus sequence analysis revealed EV-R rapidly acquired complete mutations at E145G and S241L and partial mutations at V146I of VP1, and acquired a T to C substitution at nucleotide 494 of the 5'-UTR. EV-R exhibited higher binding affinity for another EV71 receptor, human P-selectin glycoprotein ligand-1 (hPSGL-1), than EV-V. Both EV71s exhibited no significant difference in binding to hSCARB2. The molecular modelling indicate that these mutations might influence EV71 engagement with PSGL-1 and in vivo virulence.

Enterovirus 71 (EV71) is a major cause of hand, foot and mouth disease (HFMD). The current EV71 propagating in Vero (EV-V) or sub-passaged in RD (EV-R) cells was used as a pathogen. Interestingly, EV-R exhibited differential virulence; challenging human scavenger receptor class B2-expressing (hSCARB2-Tg) mice with EV71 revealed that EV-V was more virulent than EV-R: 100% of mice that received lethal amounts of EV-V died, while all the mice that received EV-R survived. Severe pathogenesis correlated with viral burdens and proinflammatory cytokine levels were observed in EV-V-challenged mice, but controversy in EV-R-challenged mice. Consensus sequence analysis revealed EV-R rapidly acquired complete mutations at E145G and S241L and partial mutations at V146I of VP1, and acquired a T to C substitution at nucleotide 494 of the 5′-UTR. EV-R exhibited higher binding affinity for another EV71 receptor, human P-selectin glycoprotein ligand-1 (hPSGL-1), than EV-V. Both EV71s exhibited no significant difference in binding to hSCARB2. The molecular modelling indicate that these mutations might influence EV71 engagement with PSGL-1 and in vivo virulence.

K2CO3 (3a)-mediated (3+2) cycloisomerization of β-ketosulfones 1 with 1,4-dichloro-2-butyne (2) in acetone afforded substituted 2-vinylfurans 4 at 56 °C for 8 h in good yields. The one-pot tandem route provides mild, facile and efficient reaction conditions. A plausible mechanism has been discussed and proposed.

In(OTf)3 (4c)-mediated one-pot (4+2) cyclocondensation of γ-alkynones 3 with N2H4(aq) in dioxane affords substituted pyridazines 5 in good yields via a sequential desulfonative or dehydrogenative aromatization. The facile transformation proceeds by a facile synthetic sequence starting with an α-propargylation of β-ketosulfones 1 and a cyclocondensation of γ-alkynones 3 with N2H4(aq). The method provides a mild and efficient condition. Moreover, this route can be enlarged to multigram scale.

Intramolecular carbonyl allylation of α-prenyl or α-geranyl β-arylketosulfones 5 in the presence of molecule sieves (MS) affords substituted benzenes 6-7 in moderate to good yields. The facile transformation proceeds by a synthetic sequence starting with the α-prenylation or α-geranylation of 1 and the Bi(OTf)3-mediated annulation of 5 followed by a sequential desulfonative aromatization or then an intramolecular Friedel-Crafts alkylation. A plausible mechanism has been studied and proposed.

With the technology development and the accuracy improvement in inertial measurement unit and micro-electromechanical system, the novel motion capture system is invented for suitable usage in natural environment or long term usage. Nevertheless, the accuracy and the consistency of the inertial measurement unit have not been provided by instructional measure system, such as robotic evaluation or standard motion capture system. Here in this study, we tested the self-development inertia sensors combined with well-programmed motion analysis software, for supporting the evidences that price less and proper software usages could afford valuable human motion variables. Results showed that in lower test speeds during the pitch and roll motions obtained reasonable root mean square value; and with further application in knee motion analysis, the abduction/ adduction and internal/ external rotation motions had great reliability for measuring body movements. With limited programming barriers needed solve, the updating motion analysis software could be applied in the clinical researches, for improving data accuracy and usage population.

A stereoselective synthesis of sulfonyl tetrahydropyrans (THPs) 6 was performed with moderate to good yields by m-CPBA (m-chloroperoxybenzoic acid)-mediated ring-closure of β-hydroxy sulfones 5. Skeleton 5 is prepared by cinnamylation of β-ketosulfones 3 in the presence of K2CO3 followed by NaBH4-mediated reduction of the resulting skeleton 4 with a α-cinnamyl side arm in the co-solvent of THF and MeOH. The key structures of skeleton 6 were confirmed by X-ray crystallographic analysis. The reaction mechanism had been discussed.

Microbial patterns are recognized by cell-surface receptors to initiate pattern-triggered immunity (PTI) in plants. Receptor-like cytoplasmic kinases (RLCKs), such as BIK1, and calcium-dependent protein kinases (CPKs) are engaged during PTI to activate the NADPH oxidase RBOHD for reactive oxygen species (ROS) production. It is unknown whether protein kinases besides CPKs and RLCKs participate in RBOHD regulation. We screened mutants in all ten Arabidopsis MAP4 kinases (MAP4Ks) and identified the conserved MAP4K SIK1 as a positive regulator of PTI. sik1 mutants were compromised in their ability to elicit the ROS burst in response to microbial features and exhibited compromised PTI to bacterial infection. SIK1 directly interacts with, phosphorylates, and stabilizes BIK1 in a kinase activity-dependent manner. Furthermore, SIK1 directly interacts with and phosphorylates RBOHD upon flagellin perception. Thus, SIK1 positively regulates immunity by stabilizing BIK1 and activating RBOHD to promote the extracellular ROS burst.

A bidirectional interleaved forward-flyback DC-DC converter with leakage energy recycled is proposed in this paper. The proposed converter uses two transformers to reduce the current stress on the power components to reduce the conduction loss and improve the efficiency. When the proposed converter is operated in the step-up mode, the voltage across switches is clamped at the input voltage, and the leakage energy is recycled to the voltage source. When the proposed converter is operated in the step-down mode, the voltage of switches is clamped at the input voltage, and the leakage energy is recycled to the clamping capacitor or the voltage source. As the proposed converter is based on flyback converter, it is characterized with simple structure. Since the leakage inductance energy is recycled, the conversion efficiency is improved compared to conventional flyback converter. Finally, a laboratory prototype circuit with 200 V/24 V and output power 500 W is implemented to verify the feasibility of the proposed converter. The highest efficiency in the step-up and step-down stage is 92.3% and 95.5% respectively.

PdCl2/CuCl2/NH4OAc-mediated the domino aerobic Wacker-type aminocyclization of α-allyl-β-ketosulfones 4 in cosolvents THF and MeOH afforded 2-(sulfonylmethyl)arylpyrroles 5 via 1,4-sulfonyl migration with moderate to good yields.

High spatial and temporal resolution microscopy-based methods are valuable tools for the precise real-time imaging of changes in cellular organization in response to stimulus perception. Here, we describe a quantitative method for the evaluation of the plant actin cytoskeleton during immune stimulus perception and the activation of defense signaling. As a measure of the biotic stress-induced changes in actin filament organization, we present methods for analyzing changes in actin filament organization following elicitation of pattern-triggered immunity and effector-triggered immunity. Using these methods, it is possible to not only quantitatively evaluate changes in actin cytoskeletal organization following biotic stress perception, but to also use these protocols to assess changes in actin filament organization following perception of a wide range of stimuli, including abiotic and developmental cues. As described herein, we present an example application of this method, designed to evaluate changes in actin cytoskeletal organization following pathogen perception and immune signaling.

Adapted filamentous pathogens such as the oomycetes Hyaloperonospora arabidopsidis (Hpa) and Phytophthora infestans (Pi) project specialized hyphae, the haustoria, inside living host cells for the suppression of host defence and acquisition of nutrients. Accommodation of haustoria requires reorganization of the host cell and the biogenesis of a novel host cell membrane, the extrahaustorial membrane (EHM), which envelops the haustorium separating the host cell from the pathogen. Here, we applied live-cell imaging of fluorescent-tagged proteins labelling a variety of membrane compartments and investigated the subcellular changes associated with accommodating oomycete haustoria in Arabidopsis and N. benthamiana. Plasma membrane-resident proteins differentially localized to the EHM. Likewise, secretory vesicles and endosomal compartments surrounded Hpa and Pi haustoria revealing differences between these two oomycetes, and suggesting a role for vesicle trafficking pathways for the pathogen-controlled biogenesis of the EHM. The latter is supported by enhanced susceptibility of mutants in endosome-mediated trafficking regulators. These observations point at host subcellular defences and specialization of the EHM in a pathogen-specific manner. Defence-associated haustorial encasements, a double-layered membrane that grows around mature haustoria, were frequently observed in Hpa interactions. Intriguingly, all tested plant proteins accumulated at Hpa haustorial encasements suggesting the general recruitment of default vesicle trafficking pathways to defend pathogen access. Altogether, our results show common requirements of subcellular changes associated with oomycete biotrophy, and highlight differences between two oomycete pathogens in reprogramming host cell vesicle trafficking for haustoria accommodation. This provides a framework for further dissection of the pathogen-triggered reprogramming of host subcellular changes.

In(OTf)3 (4c)-mediated one-pot (4+2) cyclocondensation of γ-alkynones 3 with N2H4(aq) in dioxane affords substituted pyridazines 5 in good yields via a sequential desulfonative or dehydrogenative aromatization. The facile transformation proceeds by a facile synthetic sequence starting with an α-propargylation of β-ketosulfones 1 and a cyclocondensation of γ-alkynones 3 with N2H4(aq). The method provides a mild and efficient condition. Moreover, this route can be enlarged to multigram scale.

Intramolecular carbonyl allylation of α-prenyl or α-geranyl β-arylketosulfones 5 in the presence of molecule sieves (MS) affords substituted benzenes 6–7 in moderate to good yields. The facile transformation proceeds by a synthetic sequence starting with the α-prenylation or α-geranylation of 1 and the Bi(OTf)3-mediated annulation of 5 followed by a sequential desulfonative aromatization or then an intramolecular Friedel–Crafts alkylation. A plausible mechanism has been studied and proposed.

In this paper, the design and implementation of a non-electrolytic capacitor LED driver is proposed. The proposed driver includes a Boost PFC converter as first-stage and a LLC Resonant Converter as second-stage. With feedforward control, the output current ripple can be reduced without electrolytic capacitor, the lifetime of the driver will be increased. In this paper, the operating principles of the LLC resonant Converter with feed-forward control will be discussed. Besides, the optimized design of the proposed control scheme will be discussed, too. Finally, a two-stage non electrolytic capacitor LED driver is implemented to drive 150 W LED load. Experimental results show that the proposed circuit can be operated at 90∼264V rms AC input voltage range and the highest efficiency is 90.4 %. The output current ripple and LED efficacy will be also verified.

A primary-side quasi-resonant (QR) controller IC for single-stage flyback LED driver with high power factor (PF) and low total current harmonic distortion (THDi) is proposed in this paper. Conventionally, the flyback PFC converter with critical conduction mode QR control will suffer from higher switching loss and occur higher THDi at high line condition. To solve this problem, a frequency limit QR control is proposed and analyzed. By using the proposed control, the main switch of flyback converter is turned on with valley voltage switching and the maximum frequency is limited. So that the system efficiency is increased and the input current will follow the input voltage waveform better than that with the conventional control. Finally, this controller is fabricated with TSMC 0.25 μm CMOS high voltage mixed signal general purpose process and applied to an input voltage of 90∼264 Vrms, output voltage of nominal 40 V, and constant output current of 600 mA/24W hardware prototype to verified the feasibility of the proposed control. The experimental result shows that the measured THDi is reduced from 10.5% to 3.3% at low line and 24% to 6.2% at high line compare to the critical conduction mode (CRM) QR flyback power factor correction (PFC) converter. The highest overall power efficiency is 91.4 %.

A novel interleaved flyback converter with leakage energy recycled is proposed. The proposed converter is combined with dual-switch dual-transformer flyback topology. Two clamping diodes are used to reduce the voltage stress on power switches to the input voltage level and also to recycle leakage inductance energy to the input voltage and capacitor. Besides, the interleaved control is implemented to reduce the output current ripple. In addition, the voltage on the primary windings is reduced to the half of the input voltage and thus reducing the turns ratio of transformers to improve efficiency. The operating principle and the steady state analysis of the proposed converter are discussed in detail. Finally, an experimental prototype is implemented with 400V input voltage, 24V/300W output to verify the feasibility of the proposed converter. The experimental results reveals that the highest efficiency of the proposed converter is 94.42%, the full load efficiency is 92.7%, and the 10% load efficiency is 92.61%.

The γ-alkynyl arylketones prepared from the corresponding arylketones by α-alkylation with propargyl bromides under basic conditions in high yields are efficiently converted to the corresponding substituted furan derivatives under mild reaction conditions.

A stereoselective synthesis of sulfonyl tetrahydropyrans (THPs) 6 was performed with moderate to good yields by m-CPBA (m-chloroperoxybenzoic acid)-mediated ring-closure of β-hydroxy sulfones 5. Skeleton 5 is prepared by cinnamylation of β-ketosulfones 3 in the presence of K2CO3 followed by NaBH4-mediated reduction of the resulting skeleton 4 with a α-cinnamyl side arm in the co-solvent of THF and MeOH. The key structures of skeleton 6 were confirmed by X-ray crystallographic analysis. The reaction mechanism had been discussed.

PdCl2/CuCl2/NH4OAc-mediated the domino aerobic Wacker-type aminocyclization of α-allyl-β-ketosulfones 4 in cosolvents THF and MeOH afforded 2-(sulfonylmethyl)arylpyrroles 5 via 1,4-sulfonyl migration with moderate to good yields.

A novel Bi(OTf)3-mediated cycloisomerization of γ-alkynyl arylketones 4, 7, or 10 with molecular sieve (MS) in MeNO2 affords 3-substituted furans 3, 8, or 11 at rt for 3 h in moderate to good yields. The method provides mild, less-toxic, atom-economic and efficient conditions. The mechanism has been studied and proposed. Moreover, this route can be enlarged to gram scale.

Adapted filamentous pathogens such as the oomycetes Hyaloperonospora arabidopsidis (Hpa) and Phytophthora infestans (Pi) project specialized hyphae, the haustoria, inside living host cells for the suppression of host defence and acquisition of nutrients. Accommodation of haustoria requires reorganization of the host cell and the biogenesis of a novel host cell membrane, the extrahaustorial membrane (EHM), which envelops the haustorium separating the host cell from the pathogen. Here, we applied live-cell imaging of fluorescent-tagged proteins labelling a variety of membrane compartments and investigated the subcellular changes associated with accommodating oomycete haustoria in Arabidopsis and N. benthamiana. Plasma membrane-resident proteins differentially localized to the EHM. Likewise, secretory vesicles and endosomal compartments surrounded Hpa and Pi haustoria revealing differences between these two oomycetes, and suggesting a role for vesicle trafficking pathways for the pathogen-controlled biogenesis of the EHM. The latter is supported by enhanced susceptibility of mutants in endosome-mediated trafficking regulators. These observations point at host subcellular defences and specialization of the EHM in a pathogen-specific manner. Defence-associated haustorial encasements, a double-layered membrane that grows around mature haustoria, were frequently observed in Hpa interactions. Intriguingly, all tested plant proteins accumulated at Hpa haustorial encasements suggesting the general recruitment of default vesicle trafficking pathways to defend pathogen access. Altogether, our results show common requirements of subcellular changes associated with oomycete biotrophy, and highlight differences between two oomycete pathogens in reprogramming host cell vesicle trafficking for haustoria accommodation. This provides a framework for further dissection of the pathogen-triggered reprogramming of host subcellular changes.

To successfully infect plants, filamentous pathogens such as the oomycete Hyaloperonospora arabidopsidis (Hpa) are able to penetrate host tissues and form haustoria, a feeding structure, inside the host cell. Reorganization of the host cell is required to accommodate the haustoria. Formation of haustoria is accompanied by the biogenesis of the extrahaustorial membrane (EHM) which surrounds the haustorium and separates the host cell from the pathogen. In this study, available fluorescent marker protein fusions were used to monitor the re-distribution of membrane compartments at the interface between Arabidopsis and Hpa. The aquaporin PIP1;4, the ATPase ACA8, and the plasma membrane (PM) intrinsic protein NPSN12 were excluded from the EHM while the syntaxin PEN1 and the receptor-like kinase FLS2 labelled the EHM. This suggests PM-resident proteins are recruited to the EHM selectively. The nucleus is always observed adjacent to haustoria, suggesting that the presence of haustoria causes migration of the nucleus. Secretory vesicles and endosomal compartments localize around the haustoria, implicating secretory and endocytic pathways in the biogenesis of the EHM. Upon Hpa infection, haustorial encasements develop around mature haustoria. All examined plant proteins accumulate at haustorial encasements, indicating that formation of encasements is derived by default redirection of vesicle trafficking pathways. With the aim to genetically dissect endosomal trafficking regulators, I took advantage of quantitative high throughput confocal imaging system and transgenic plants containing the fluorescent biosensor GFP-2xFYVE to perform a forward genetic screen. Different numbers of GFP-2xFYVE positive endosomes were found in two reference lines, Ler/GFP-2xFYVE and Col-0/YFP-2xFYVE suggesting the endosomal levels may vary in different ecotypes of Arabidopsis. Mutants with altered numbers of FYVE Endosomal Levels (fel) have been previous identified and were re-confirmed in this study. fel1, fel2, fel3, fel6, fel9, and fel12 revealed genetically recessive mutations while fel10 could not reveal its genetic inheritance. Two mutants, fel2 and fel9 exhibited more GFP-2xFYVE compartments than wild-type reference plants. These two mutants are affected in endosome trafficking and fel2 is likely tissue specific. We identified gene loci by classical mapping and whole genome sequencing. Fel2 co-segregated with the lower arm of chromosome 4. Fel9 was mapped to two chromosome loci. Investigation of genes in the rough mapping region will unravel regulators of endocytosis or multivesicular bodies (MVBs) biogenesis. Because only few mutant phenotypes recovered in the F2 of backcrossed fel2 and fel9, identification of FEL2 and FEL9 was hampered. Additionally, basal differences of endosomal numbers in the reference lines lead to the limitation for genetic screen based on quantitative changes in endosomal numbers. Altogether, these results show that there are common elements in the subcellular changes associated with biotrophic oomycete between different pathogens. For Hpa and other fungal/oomycete pathogens, reprogramming host cell vesicle trafficking occurs to accommodate haustorial structures. A genetic screen for novel endocytosis mutants, based on quantitative measurements of endosomal numbers, was performed with advanced microscopy technology. Fel mutant plants may be further used to study molecular mechanisms for membrane trafficking, as well as subcellular rearrangement in plant-pathogen interactions.