Flourishing in water: the early evolution and diversification of plant receptor-like kinases

Receptor-like kinases (RLKs) play significant roles in mediating innate immunity and development of plants. The evolution of plant RLKs has been characterized by extensive variation in copy numbers and domain configurations. However, much remains unknown about the origin, evolution, and early diversification of plant RLKs. Here, we perform phylogenomic analyses of RLKs across plants (Archaeplastida), including embryophytes, charophytes, chlorophytes, prasinodermophytes, glaucophytes, and rhodophytes. We identify the presence of RLKs in all the streptophytes (land plants and charophytes), nine out of 18 chlorophytes, one prasinodermophyte, and one glaucophyte, but not in rhodophytes. Interestingly, the copy number of RLKs increased drastically in streptophytes after the split of the clade of Mesostigmatophyceae and Chlorokybophyceae and other streptophytes. Moreover, phylogenetic analyses suggest RLKs from charophytes form diverse distinct clusters, and are dispersed along the diversity of land plant RLKs, indicating that RLKs have extensively diversified in charophytes and charophyte RLKs seeded the major diversity of land plant RLKs. We identify at least 81 and 76 different kinase-associated domains for charophyte and land plant RLKs, 23 of which are shared, suggesting that RLKs might have evolved in a modular fashion through frequent domain gains or losses. We also detect signatures of positive selection for many charophyte RLK groups, indicating potential functions in host–microbe interaction. Taken together, our findings provide significant insights into the early evolution and diversification of plant RLKs and the ancient evolution of plant–microbe symbiosis.     

S-acylation stabilizes ligand-induced receptor kinase complex formation during plant pattern-triggered immune signaling

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Patterning the embryo in higher plants: Emerging pathways and challenges

Embryogenesis, which establishes the basic body plan for the post-embryonic organs after stereotyped cell divisions, initiates the first step of the plant life cycle. Studies in the last two decades indicate that embryogenesis is a precisely controlled process, and any defect would result in abnormalities. Here we discuss the recent progresses, with a focus on the cellular pathways governing early embryogenesis in the model species Arabidopsis.     

SPdel: A pipeline to compare and visualize species delimitation methods for single-locus datasets

An accurate species delimitation is critical for biological studies. In this context, the use of molecular techniques along with species delimitation methods would help to a rapid and accurate biodiversity assessment. The species delimitation methods cluster data sets of orthologous sequences in molecular operational taxonomic units (MOTU). In particular, the methods based on a single gene are easily integrated with the widely used DNA barcoding approach. We developed SPdel a user-friendly pipeline to integrate different single-gene species delimitation methods. SPdel is designed to calculate and compare MOTUs obtained by different species delimitation approaches. SPdel also outputs diverse ready-to-publish quality figures, that facilitate the interpretation of results. SPdel aims to help researchers use species delimitation methods that would improve biodiversity studies.     

A novel protein elicitor (PeSy1) from Saccharothrix yanglingensis induces plant resistance and interacts with a receptor-like cytoplasmic kinase in Nicotiana benthamiana

Previously, we reported a rare actinomycete Saccharothrix yanglingensis Hhs.015 with strong biocontrol ability, which can colonize plant tissues and induce resistance, but the key elicitor and immune mechanisms were unclear. In this study, a novel protein elicitor screened from the genome of Hhs.015, PeSy1 (protein elicitor of S. yanglingensis 1), could induce a strong hypersensitive response (HR) and resistance in plants. The PeSy1 gene encodes an 11 kDa protein with 109 amino acids that is conserved in Saccharothrix species. PeSy1-His recombinant protein induced early defence events such as a cellular reactive oxygen species burst, callose deposition, and the activation of defence hormone signalling pathways, which enhanced Nicotiana benthamiana resistance to Sclerotinia sclerotiorum and Phytophthora capsici, and Solanum lycopersicum resistance to Pseudomonas syringae pv. tomato DC3000. Through pull-down and mass spectrometry, candidate proteins that interacted with PeSy1 were obtained from N. benthamiana. We confirmed the interaction between receptor-like cytoplasmic kinase RSy1 (Response to PeSy1) and PeSy1 using co-immunoprecipitation, bimolecular fluorescence complementation, and microscale thermophoresis. PeSy1 treatment promoted up-regulation of marker genes in pattern-triggered immunity. The cell death it elicited was dependent on the co-receptors NbBAK1 and NbSOBIR1, suggesting that PeSy1 acts as a microbe-associated molecular pattern from Hhs.015. Additionally, RSy1 positively regulated PeSy1-induced plants resistant to S. sclerotiorum. In conclusion, our results demonstrated a novel receptor-like cytoplasmic kinase in the plant perception of microbe-associated molecular patterns, and the potential of PeSy1 in induced resistance provided a new strategy for biological control of actinomycetes in agricultural diseases.     

Objective Evaluation of Soy Sauce by Statistical Analysis of GC Profiles

The relationships between GC data of volatiles and sensory score of the heighest grade of soy sauce (Tokusen shoyu) were analyzed by multivariate analyses. Samples belonging to four brands could be unambiguously classified into the correct brands and the statistical distance among them suggested a close relation with sensory evaluation. The precise predictive equations for the aroma quality were calculated from GC data and sensory evaluation by multiple regression analysis. Eight principal components were extracted from 39 GC peaks as significant factors constituting soy sauce aroma. The second PC can explain 58% of the variation among total variation contained in the sensory score. Discriminant functions on the basis of the 8 PCs can clearly classify all samples.     

Neuroinflammatory disease disrupts the blood-CNS barrier via crosstalk between proinflammatory and endothelial-to-mesenchymal-transition signaling

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Therapeutic approaches for the treatment of head and neck squamous cell carcinoma–An update on clinical trials

Head and neck squamous cell carcinoma (HNSCC) is the sixth most common non-skin cancer with a tobacco consumption and infection with high-risk human papillomavirus (HPV) being major risk factors. Despite advances in numerous therapy modalities, survival rates for HNSCC have not improved considerably; a vast number of clinical outcomes have demonstrated that a combination strategy (the most well-known docetaxel, cisplatin, and 5-fluorouracil) is the most effective treatment choice. Immunotherapy that targets immunological checkpoints is being tested in a number of clinical trials, either alone or in conjunction with chemotherapeutic or targeted therapeutic drugs. Various monoclonal antibodies, such as cetuximab and bevacizumab, which target the EGFR and VEGFR, respectively, as well as other signaling pathway inhibitors, such as temsirolimus and rapamycin, are also being studied for the treatment of HNSCC. We have reviewed the primary targets in active clinical studies in this study, with a particular focus on the medications and drug targets used.     

Long-distance turgor pressure changes induce local activation of plant glutamate receptor-like channels

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