Induced proximity of a TIR signaling domain on a plant-mammalian NLR chimera activates defense in plants

Plant and animal intracellular nucleotide-binding, leucine-rich repeat (NLR) immune receptors detect pathogen-derived molecules and activate defense. Plant NLRs can be divided into several classes based upon their N-terminal signaling domains, including TIR (Toll-like, Interleukin-1 receptor, Resistance protein)- and CC (coiled-coil)-NLRs. Upon ligand detection, mammalian NAIP and NLRC4 NLRs oligomerize, forming an inflammasome that induces proximity of its N-terminal signaling domains. Recently, a plant CC-NLR was revealed to form an inflammasome-like hetero-oligomer. To further investigate plant NLR signaling mechanisms, we fused the N-terminal TIR domain of several plant NLRs to the N terminus of NLRC4. Inflammasome-dependent induced proximity of the TIR domain in planta initiated defense signaling. Thus, induced proximity of a plant TIR domain imposed by oligomerization of a mammalian inflammasome is sufficient to activate authentic plant defense. Ligand detection and inflammasome formation is maintained when the known components of the NLRC4 inflammasome is transferred across kingdoms, indicating that NLRC4 complex can robustly function without any additional mammalian proteins. Additionally, we found NADase activity of a plant TIR domain is necessary for plant defense activation, but NADase activity of a mammalian or a bacterial TIR is not sufficient to activate defense in plants

Distinct modes of derepression of an Arabidopsis immune receptor complex by two different bacterial effectors

Plant intracellular nucleotide-binding leucine-rich repeat (NLR) immune receptors often function in pairs to detect pathogen effectors and activate defense. The Arabidopsis RRS1-R–RPS4 NLR pair recognizes the bacterial effectors AvrRps4 and PopP2 via an integrated WRKY transcription factor domain in RRS1-R that mimics the effector’s authentic targets. How the complex activates defense upon effector recognition is unknown. Deletion of the WRKY domain results in an RRS1 allele that triggers constitutive RPS4-dependent defense activation, suggesting that in the absence of effector, the WRKY domain contributes to maintaining the complex in an inactive state. We show the WRKY domain interacts with the adjacent domain 4, and that the inactive state of RRS1 is maintained by WRKY–domain 4 interactions before ligand detection. AvrRps4 interaction with the WRKY domain disrupts WRKY–domain 4 association, thus derepressing the complex. PopP2-triggered activation is less easily explained by such disruption and involves the longer C-terminal extension of RRS1-R. Furthermore, some mutations in RPS4 and RRS1 compromise PopP2 but not AvrRps4 recognition, suggesting that AvrRps4 and PopP2 derepress the complex differently. Consistent with this, a “reversibly closed” conformation of RRS1-R, engineered in a method exploiting the high affinity of colicin E9 and Im9 domains, reversibly loses AvrRps4, but not PopP2 responsiveness. Following RRS1 derepression, interactions between domain 4 and the RPS4 C-terminal domain likely contribute to activation. Simultaneous relief of autoinhibition and activation may contribute to defense activation in many immune receptors

Exploring policies, practices and orientations towards English as a medium of instruction in Chinese Higher Education

This study examines subject teachers’ orientations and implementation of English as a medium of instruction in Chinese universities, against a background of the internationalisation of higher education. The study also explores the way in which English as a medium of instruction policies are actualized in teaching practices. The study is informed by English as a lingua franca perspective on English communication, language policy theory and English as a lingua franca in academic settings.This study draws on data retrieved through questionnaires, interviews and classroom observations. 106 questionnaires were collected, 14 interviews were conducted and 15 hours of classroom observations were analysed. The findings of the study suggest the majority of teachers favour English as a medium of instruction, while at the same time pointing out concerns regarding the teaching quality, and ambivalent language policy, as well as some perceptions towards attachment to native English ideology. The participants have ambivalent orientations towards English use; on the one hand, exhibited native-like competency was still considered as important for many teachers. On the other hand, the responses of the participants revealed their belief in the need to communicate effectively rather than aiming at native speaker competency in practice. In addition, both questionnaire and interview findings reveal that the English language policy in China is still based on native speaker English, but that teachers and students are using ELF in practice. The classroom observations suggest that some teachers adopted ELF orientated approach in their practices. The data analysis confirmed the existence of a gap between policy as stated and the implementation of the policy.The findings of this study can contribute to ELF, EMI, and language policy research. It is argued that the ELF concept should expand to include interlocutors from the same language cultural background. It is suggested that English policy and ELT in China should take account of the students’ future needs and the global use of English. Thus, the traditional native-normative approach to English language should be questioned. The findings also raise questions as to how English as a medium of instruction in China could be implemented effectively.<br/

China Type Asian Economic System

China initiates the "One Belt One Road" (OBOR) expansion strategy which is composed of the Silk Road Economic Belt (SREB) and 21st Century Maritime Silk Road (21st CMSR) expansion sub-strategies, seeking to integrate the 27 countries (perhaps 65 ones around the world) along the lines of OBOR Asian economic system with a demography of 4.4 billion, $US 21-trillion- dollar giant market into China type Asian economic system via the OBOR expansion strategy. On the one hand, China can exert itself in giving full play in the following advantageous areas such as the construction of infrastructure, high-speed railway, nuclear energy, industrial manufacturing, e-commerce, military manufacturing, etc.; on the other hand, China can also shift its surplus production capacity, capital, technology as well as labor-intensive industries into establishing China type Asian economic system so that China’s dream for interconnectivity, common prosperity and rise of Asia comes true finally

Overseas Chinese students' perceptions of the influence of English on their language and culture

The English language today functions as a lingua franca with the largest number of learners and users of any language. As an international language, it has attracted much attention in terms of its impacts on other languages. As another key language with the largest number of native speakers, the Chinese language has also demonstrated a global status, with an increasing number of language learners and users. This paper investigates Chinese overseas students’ perceptions of the influence of English on the Chinese language and culture. By adopting a series of qualitative interviews, this paper researches the attitudes of overseas Chinese students studying in the UK towards the influence of English on the Chinese language. In order to explore how the uses of English influence the Chinese language in the Chinese context, the paper investigates students’ attitudes towards the Gaokao reform, the influence of English on Chinese language and culture, and the future use of English in China. It concludes that, although the Chinese language is developing quite rapidly with both L1 and L2 speakers, English represents an important channel for people’s personal development, and English as a lingua franca will continue to be used for a range of purposes in many Chinese people’s lives for some time to come. <br/

Shoot Maturation Strengthens FLS2-Mediated Resistance to Pseudomonas syringae

Temporospatial regulation of immunity components is essential for properly activating plant defense response. Flagellin-sensing 2 (FLS2) is a surface-localized receptor that recognizes bacterial flagellin. The immune function of FLS2 is compromised in early stages of shoot development. However, the underlying mechanism for the age-dependent FLS2 signaling is not clear. Here, we show that the reduced basal immunity of juvenile leaves against Pseudomonas syringae pv. tomato DC3000 is independent of FLS2. The flg22-induced marker gene expression and reactive oxygen species activation were comparable in juvenile and adult stages, but callose deposition was more evident in the adult stage than the juvenile stage. We further demonstrated that microRNA156, a master regulator of plant aging, does not influence the expression of FLS2 and FRK1 (Flg22-induced receptor-like kinase 1) but mildly suppresses callose deposition in juvenile leaves. Our experiments revealed an intrinsic mechanism that regulates the amplitude of FLS2-mediated resistance during aging. [Graphic: see text] Copyright © 2023 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license

Distinct function of SPL genes in age-related resistance in Arabidopsis.

In plants, age-related resistance (ARR) refers to a gain of disease resistance during shoot or organ maturation. ARR associated with vegetative phase change, a transition from juvenile to adult stage, is a widespread agronomic trait affecting resistance against multiple pathogens. How innate immunity in a plant is differentially regulated during successive stages of shoot maturation is unclear. In this work, we found that Arabidopsis thaliana showed ARR against its bacterial pathogen Pseudomonas syringae pv. tomato DC3000 during vegetative phase change. The timing of the ARR activation was associated with a temporal drop of miR156 level. The microRNA miR156 maintains juvenile phase by inhibiting the accumulation and translation of SPL transcripts. A systematic inspection of the loss- and gain-of-function mutants of 11 SPL genes revealed that a subset of SPL genes, notably SPL2, SPL10, and SPL11, activated ARR in adult stage. The immune function of SPL10 was independent of its role in morphogenesis. Furthermore, the SPL10 mediated an age-dependent augmentation of the salicylic acid (SA) pathway partially by direct activation of PAD4. Disrupting SA biosynthesis or signaling abolished the ARR against Pto DC3000. Our work demonstrated that the miR156-SPL10 module in Arabidopsis is deployed to operate immune outputs over developmental timing

Bufei Jianpi Granules Reduce Quadriceps Muscular Cell Apoptosis by Improving Mitochondrial Function in Rats with Chronic Obstructive Pulmonary Disease

Background. Cell apoptosis is an important mechanism underlying skeletal muscle dysfunction in chronic obstructive pulmonary disease (COPD) patients, and mitochondrial dysfunction is recognized as a central aspect contributing to skeletal muscle deterioration. Bufei Jianpi granules have been confirmed effective for improving motor function in COPD patients, but the specific mechanism for this improved function remains unknown. This study explored the mechanisms by which Bufei Jianpi granules improve cell apoptosis and mitochondrial dysfunction in COPD. Methods. Sprague-Dawley rats were randomized into control, model, Bufei Jianpi, and aminophylline groups. A stable COPD rat model was induced with respective repeated cigarette smoke inhalation and intragastric bacterial infection, and rats were sacrificed after 20 weeks; the quadriceps muscle was harvested from each rat. Skeletal muscle mitochondria were extracted for measurements of mitochondrial membrane potential (MMP) and mitochondrial permeability transition pore openings (mPTPs). ATP levels were determined with a firefly luciferase-based ATP assay kit. The rates of cell apoptosis were determined by the transferase-mediated deoxyuridine triphosphate-biotin nick end labeling (TUNEL) method. Cyto C and caspase-3 mRNA and protein levels were measured by qPCR and western blotting. Results. ATP, MMP, and mPTPs were markedly decreased in COPD rats, while cell apoptosis, caspase-3, and Cyto C were increased (P<0.01). All aforementioned parameters were improved in treatment groups (P<0.05). ATP, MMP, and mPTPs were significantly higher in the Bufei Jianpi group than in the aminophylline group, while cell apoptosis, caspase-3, and Cyto C were lower (P<0.05). Conclusions. Bufei Jianpi granules can inhibit mitochondrial dysfunction and cell apoptosis in peripheral muscles, which might be the mechanism involved in improving skeletal muscle function in COPD patients