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As the major sensor of adaptive immune system, T cell receptor (TCR) can recognize diverse antigens and initiate specific immune responses against invading pathogens and cancer cells. Understanding the mechanisms of TCR signaling has led to the development of engineered T cell therapies, which have extensive applications in the treatment of diseases such as cancer, infection and autoimmunity. Here, we review the current understanding of antigen-induced TCR signaling and discuss its applications in T cell therapies.

Selective autophagy of damaged mitochondria, protein aggregates, and other cargoes is essential for health. Cargo initiates phagophore biogenesis, which entails the conjugation of LC3 to phosphatidylethanolamine. Current models suggest that clustered ubiquitin chains on a cargo trigger a cascade from autophagic cargo receptors through the core complexes ULK1 and class III phosphatidylinositol 3-kinase complex I, WIPI2, and the ATG7, ATG3, and ATG12ATG5-ATG16L1 machinery of LC3 lipidation. This was tested using giant unilamellar vesicles (GUVs), GST-Ub4 as a model cargo, the cargo receptors NDP52, TAX1BP1, and OPTN, and the autophagy core complexes. All three cargo receptors potently stimulated LC3 lipidation on GUVs. NDP52- and TAX1BP1-induced LC3 lipidation required all components, but not ULK1 kinase activity. However, OPTN bypassed the ULK1 requirement. Thus, cargo-dependent stimulation of LC3 lipidation is common to multiple autophagic cargo receptors, yet the details of core complex engagement vary between the different receptors.

The selective autophagy pathways of xenophagy and mitophagy are initiated when the adaptor NDP52 recruits the ULK1 complex to autophagic cargo. Hydrogen-deuterium exchange coupled to mass spectrometry (HDX-MS) was used to map the membrane and NDP52 binding sites of the ULK1 complex to unique regions of the coiled coil of the FIP200 subunit. Electron microscopy of the full-length ULK1 complex shows that the FIP200 coiled coil projects away from the crescent-shaped FIP200 N-terminal domain dimer. NDP52 allosterically stimulates membrane-binding by FIP200 and the ULK1 complex by promoting a more dynamic conformation of the membrane-binding portion of the FIP200 coiled coil. Giant unilamellar vesicle (GUV) reconstitution confirmed that membrane recruitment by the ULK1 complex is triggered by NDP52 engagement. These data reveal how the allosteric linkage between NDP52 and the ULK1 complex could drive the first membrane recruitment event of phagophore biogenesis in xenophagy and mitophagy.

The autophagy-initiating human ULK complex consists of the kinase ULK1/2, FIP200, ATG13, and ATG101. Hydrogen-deuterium exchange mass spectrometry was used to map their mutual interactions. The N-terminal 640 residues (NTD) of FIP200 interact with the C-terminal IDR of ATG13. Mutations in these regions abolish their interaction. Negative stain EM and multiangle light scattering showed that FIP200 is a dimer, while a single molecule each of the other subunits is present. The FIP200NTD is flexible in the absence of ATG13, but in its presence adopts the shape of the letter C ∼20 nm across. The ULK1 EAT domain interacts loosely with the NTD dimer, while the ATG13:ATG101 HORMA dimer does not contact the NTD. Cryo-EM of the NTD dimer revealed a structural similarity to the scaffold domain of TBK1, suggesting an evolutionary similarity between the autophagy-initiating TBK1 kinase and the ULK1 kinase complex.

Macroautophagy/autophagy mediates the degradation of ubiquitinated aggregated proteins within lysosomes in a process known as aggrephagy. The cargo receptor SQSTM1/p62 condenses aggregated proteins into larger structures and links them to the nascent autophagosomal membrane (phagophore). How the condensation reaction and autophagosome formation are coupled is unclear. We recently discovered that a region of SQSTM1 containing its LIR motif directly interacts with RB1CC1/FIP200, a protein acting at early stages of autophagosome formation. Determination of the structure of the C-terminal region of RB1CC1 revealed a claw-shaped domain. Using a structure-function approach, we show that the interaction of SQSTM1 with the RB1CC1 claw domain is crucial for the productive recruitment of the autophagy machinery to ubiquitin-positive condensates and their subsequent degradation by autophagy. We also found that concentrated Atg8-family proteins on the phagophore displace RB1CC1 from SQSTM1, suggesting an intrinsic directionality in the process of autophagosome formation. Ultimately, our study reveals how the interplay of SQSTM1 and RB1CC1 couples cargo condensation to autophagosome formation.

The autophagy cargo receptor p62 facilitates the condensation of misfolded, ubiquitin-positive proteins and their degradation by autophagy, but the molecular mechanism of p62 signaling to the core autophagy machinery is unclear. Here, we show that disordered residues 326-380 of p62 directly interact with the C-terminal region (CTR) of FIP200. Crystal structure determination shows that the FIP200 CTR contains a dimeric globular domain that we designated the "Claw" for its shape. The interaction of p62 with FIP200 is mediated by a positively charged pocket in the Claw, enhanced by p62 phosphorylation, mutually exclusive with the binding of p62 to LC3B, and it promotes degradation of ubiquitinated cargo by autophagy. Furthermore, the recruitment of the FIP200 CTR slows the phase separation of ubiquitinated proteins by p62 in a reconstituted system. Our data provide the molecular basis for a crosstalk between cargo condensation and autophagosome formation.

Single‐cell sorting (index sorting) is a widely used method to isolate one cell at a time using fluorescence‐activated cell sorting (FACS) for downstream applications such as single‐cell sequencing or single‐cell expansion. Despite widespread use, few assays are available to evaluate the proteomic features of the sorted single cell and further confirm the accuracy of single‐cell sorting. With this caveat, we developed a novel assay to confirm the protein expression of sorted single cells by co‐staining cells with the same marker using both antibody‐derived tags (ADTs) and fluorescent antibodies. After single‐cell sorting, we amplified the oligo of the ADT reagent as a surrogate signal for the protein expression using multiplex TaqMan™ qPCR on sorted cells. This assay is not only useful for confirming the identity of a sorted single cell but also an efficient method to profile proteomic features at the single‐cell level. Finally, we applied this assay to characterize protein expression on whole cell lysate. Because of the sensitivity of the TaqMan™ qPCR, we can detect protein expression from a small number of cells. In summary, the ADT‐based qPCR assay developed here can be utilized to confirm single‐cell sorting accuracy and characterizing protein expression on both single cells and whole cell lysate. [ABSTRACT FROM AUTHOR]

Today, pathogenic microorganisms are increasingly developing resistance to conventional drugs, necessitating the exploration of alternative strategies. In addressing this challenge, nano-based antibacterial agents offer a promising avenue of research. In the present study, we used an extract of Moringa oleifera, a widely recognized edible and medicinal plant, to synthesize biogenetic tellurium nanoparticles (Bio-TeNPs). Transmission electron microscopy, scanning electron microscopy, and dynamic light scattering analyses revealed that the obtained Bio-TeNPs had diameters between 20 and 50 nm, and zeta potential values of 23.7 ± 3.3 mV. Fourier-transform infrared spectroscopy and X-ray photoelectron spectroscopy revealed that the Bio-TeNPs consisted primarily of Te(0), along with some organic constituents. Remarkably, these Bio-TeNPs exhibited potent antibacterial activity against a spectrum of pathogens, including Escherichia coli, Klebsiella pneumoniae, Shigella dysenteriae, Salmonella typhimurium, Streptococcus pneumoniae, and Streptococcus agalactiae. In addition, findings from growth curve experiments, live/dead cell staining, and scanning electron microscopy observations of cell morphology demonstrated that Bio-TeNPs at a concentration of 0.07 mg/mL effectively disrupted E. coli and K. pneumoniae cells, leading to cell rupture or shrinkage. The biofilm inhibition rates of 0.7 mg/mL Bio-TeNPs against E. coli and K. pneumoniae reached 92% and 90%, respectively. In addition, 7 mg/mL Bio-TeNPs effectively eradicated E. coli from the surfaces of glass slides, with a 100% clearance rate. These outcomes underscore the exceptional antibacterial efficacy of Bio-TeNPs and highlight their potential as promising nanomaterials for combating bacterial infections. [ABSTRACT FROM AUTHOR]

Cellular Indexing of Transcriptomes and Epitopes by Sequencing (CITE‐Seq) is a single‐cell phenotyping method that uses antibody‐derived tags (ADTs) to quantitatively detect cell surface protein expression and generate transcriptomic data at the single‐cell level. Despite the increased popularity of this technique to study cellular heterogeneity and dynamics, detailed methods on how to choose ADT markers and ensuring reagent performance in biological relevant systems prior to sequencing is not available. Here we describe a novel and easy‐to‐use multiplex flow proxy assay in which multiple protein markers can be measured simultaneously using a combination of ADT reagents and dye‐oligo conjugates by flow cytometry. Using dye‐oligo conjugates with sequences complementary to the ADT reagents, we can achieve specific binding and evaluate protein marker expression in a multiplex way. This quality control assay is useful for guiding ADT marker choice and confirming protein expression prior to sequencing. Importantly, the labeled cells can be directly isolated based on the specific fluorescence from dye‐oligo conjugates using a flow cytometry cell sorter and processed for downstream single‐cell multiomics. Using this streamlined workflow, we sorted natural killer cells and T cells efficiently using only ADT and dye‐oligo reagents, avoiding the possibility of decreased marker resolution from co‐staining cells with ADT and fluorescent antibodies. This novel workflow provides a viable option for improving ADT marker choice and cell sorting efficiency, allowing subsequent CITE‐Seq. [ABSTRACT FROM AUTHOR]

Due to the "shuttle effect" and low conversion kinetics of polysulfides, the cycle stability of lithium sulfur (Li−S) battery is unsatisfactory, which hinders its practical application. The Mott‐Schottky heterostructures for Li−S batteries not only provide more catalytic/adsorption active sites, but also facilitate electrons transport by a built‐in electric field, which are both beneficial for polysulfides conversion and long‐term cycle stability. Here, MXene@WS2 heterostructure was constructed by in‐situ hydrothermal growth for separator modification. In‐depth ultraviolet photoelectron spectroscopy and ultraviolet visible diffuse reflectance spectroscopy analysis reveals that there is an energy band difference between MXene and WS2, confirming the heterostructure nature of MXene@WS2. DFT calculations indicate that the Mott‐Schottky MXene@WS2 heterostructure can effectively promote electron transfer, improve the multi‐step cathodic reaction kinetics, and further enhance polysulfides conversion. The built‐in electric field of the heterostructure plays an important role in reducing the energy barrier of polysulfides conversion. Thermodynamic studies reveal the best stability of MXene@WS2 during polysulfides adsorption. As a result, the Li−S battery with MXene@WS2 modified separator exhibits high specific capacity (1613.7 mAh g−1 at 0.1 C) and excellent cycling stability (2000 cycles with 0.0286 % decay per cycle at 2 C). Even at a high sulfur loading of 6.3 mg cm−2, the specific capacity could be retained by 60.0 % after 240 cycles at 0.3 C. This work provides deep structural and thermodynamic insights into MXene@WS2 heterostructure and its promising prospect of application in high performance Li−S batteries. [ABSTRACT FROM AUTHOR]

With the coal mines in western China entering the field of deep mining, the problem of coal burst is becoming more and more serious. According to the characteristics of deep mining, it is an urgent problem that requires the development of an efficient and reasonable coal burst prevention and control plan to guide project practices. This study takes the typical deep mining area in Ordos as the research background, according to the stress state of the coal mining area and the load form of induced coal burst, which, in Ordos deep mining, is divided into the typical and atypical type. The former is caused by the superposition of high in situ stress and strong mining-induced stress, while the latter is due to the combination of high in situ stress, strong mining-induced stress, and external stress disturbances. Combined with theoretical analysis, numerical simulation, and field measurement, it is shown that the stress level of the Ordos deep mining area is higher than that of the shallow original rock, and the difference of the three-dimensional stress between coal and rock mass is greater. The concentration degree and influence range of mining-induced stress obviously increase. Coal and rock mass are more prone to instability and failure due to external disturbances. Based on the stress control theory, the prevention and control strategies of coal burst in different types of deep mining are put forward. In addition, the prevention and control technology system of coal burst in the Ordos deep mining area is established. The field engineering practice has been carried out to realize the efficient prevention and control of coal burst. [ABSTRACT FROM AUTHOR]

Ionic protein-lipid interactions are critical for the structure and function of membrane receptors, ion channels, integrins and many other proteins (1-7). However, the regulatory mechanism of these interactions is largely [...]