Causal association between phenylalanine and Parkinson's disease: a two-sample bidirectional mendelian randomization study.

Background: Research findings indicate a putative indirect or latent association between phenylalanine (Phe) and Parkinson's disease (PD). In this study, we aimed to analyze the causal relationship between Phe and PD by two sample Mendelian randomization (MR) analysis. Methods: In this study, the PD-related dataset and Phe-related dataset were downloaded from Integrative Epidemiology U1nit (IEU) Open Genome-Wide Association Study (GWAS) database. Four algorithms (MR Egger, maximum likelihood, inverse variance weighting (IVW) and unweighted regression) were used to perform MR analysis. The sensitivity analysis (heterogeneity test, horizontal pleiotropy test and Leave-One-Out (LOO) analysis) was used to assess the reliability of MR analyses. Results: In the forward MR analysis, Phe was a safety factor for PD (p-value < 0.05 and odds ratios (OR) < 1). The results of reverse MR analysis showed that there was no causal relationship between PD and Phe (p-value > 0.05). In addition, sensitivity analysis showed that MR analysis was reliable. Conclusion: The results of this study revealed that Phe was a safety factor for PD, meaning that Phe reduced the risk of PD.

Advances in pH Sensing: From Traditional Approaches to Next-Generation Sensors in Biological Contexts.

pH has been considered one of the paramount factors in bodily functions because most cellular tasks exclusively rely on precise pH values. In this context, the current techniques for pH sensing provide us with the futuristic insight to further design therapeutic and diagnostic tools. Thus, pH-sensing (electrochemically and optically) is rapidly evolving toward exciting new applications and expanding researchers' interests in many chemical contexts, especially in biomedical applications. The adaptation of cutting-edge technology is subsequently producing the modest form of these biosensors as wearable devices, which are providing us the opportunity to target the real-time collection of vital parameters, including pH for improved healthcare systems. The motif of this review is to provide insight into trending tech-based systems employed in real-time or in-vivo pH-responsive monitoring. Herein, we briefly go through the pH regulation in the human body to help the beginners and scientific community with quick background knowledge, recent advances in the field, and pH detection in real-time biological applications. In the end, we summarize our review by providing an outlook; challenges that need to be addressed, and prospective integration of various pH in vivo platforms with modern electronics that can open new avenues of cutting-edge techniques for disease diagnostics and prevention.

Population coding for figure-ground texture segregation in macaque V1 and V4.

Object recognition often involves the brain segregating objects from their surroundings. Neurophysiological studies of figure-ground texture segregation have yielded inconsistent results, particularly on whether V1 neurons can perform figure-ground texture segregation or just detect texture borders. To address this issue from a population perspective, we utilized two-photon calcium imaging to simultaneously record the responses of large samples of V1 and V4 neurons to figure-ground texture stimuli in awake, fixating macaques. The average response changes indicate that V1 neurons mainly detect texture borders, while V4 neurons are involved in figure-ground segregation. However, population analysis (SVM decoding of PCA-transformed neuronal responses) reveal that V1 neurons not only detect figure-ground borders, but also contribute to figure-ground texture segregation, although requiring substantially more principal components than V4 neurons to reach a 75 % decoding accuracy. Individually, V1/V4 neurons showing larger (negative/positive) figure-ground response differences contribute more to figure-ground segregation. But for V1 neurons, the contribution becomes significant only when many principal components are considered. We conclude that V1 neurons participate in figure-ground segregation primarily by defining the figure borders, and the poorly structured figure-ground information V1 neurons carry could be further utilized by V4 neurons to accomplish figure-ground segregation.

Natural aromatic extract of black tea improved the water retention of pork meat batter.

The effect of varying proportions (w/w) of natural aromatic extract of black tea (NAEBT) with pre-emulsification on the water-holding capacity (WHC) of pork meat batter was investigated. The addition of NAEBT significantly reduced the cooking loss (CL) of pork meat batter from 23.95 % to 18.30 % (P < 0.05). Furthermore, NAEBT with pre-emulsification significantly improved the color stability and increased the springiness (P < 0.05). The results of TBARS and carbonyls indicated that NAEBT with pre-emulsification significantly alleviated oxidative damage to proteins (P < 0.05), resulting in an increased level of ß-sheet (P < 0.05), as confirmed by FT-IR analysis. As a result, the water mobility of pork meat batter was restricted (P < 0.05), resulting in an increase in the energy storage modulus (P < 0.05) and a decrease in the pore size. In summary, the WHC of pork meat batter was improved by the antioxidant effect of the NAEBT.

Pre-school children single inhalation anesthetic exposure and neuro-psychological development: a prospective study and Mendelian randomization analysis.

Background: For children who are unable to cooperate due to severe dental anxiety (DA), dental treatment of childhood caries under Dental General Anesthesia (DGA) is a safe and high-quality treatment method. This study aims to evaluate the impact on neurocognitive functions and the growth and development of children 2 years after dental procedure based on previous research, and further establish a causal relationship between general anesthesia (GA) and changes in children's neurocognitive functions by incorporating Mendelian Randomization (MR) analysis. Methods: Data were collected and analyzed from 340 cases of S-ECC procedures of preschool children conducted in 2019. This involved comparing the neurocognitive outcomes 2 years post-operation of preschool children receiving dental procedures under general anesthesia or local anesthesia. Physical development indicators such as height, weight, and body mass index (BMI) of children were also compared at baseline, half a year post-operation, and 2 years post-operation. We performed a Mendelian randomization analysis on the causal relationship between children's cognitive development and general anesthesia, drawing on a large-scale meta-analysis of GWAS for anesthesia, including multiple general anesthesia datasets. Results: Outcome data were obtained for 111 children in the general anesthesia group and 121 children in the local anesthesia group. The mean FSIQ score for the general anesthesia group was 106.77 (SD 6.96), while the mean score for the local anesthesia group was 106.36 (SD 5.88). FSIQ scores were equivalent between the two groups. The incidence of malnutrition in children in the general anesthesia group was 27.93% (p < 0.001) before surgery and decreased to 15.32% (p > 0.05) after 2 years, which was not different from the general population. The IVW method suggested that the causal estimate (p = 0.99 > 0.05, OR = 1.04, 95% CI = 5.98 × 10-4-1.82 × 103) was not statistically significant for disease prevalence. This indicates no genetic cause-and-effect relationship between anesthesia and childhood intelligence. Conclusion: There were no adverse outcomes in neurocognitive development in 2 years after severe early childhood caries (S-ECC) procedure under total sevoflurane-inhalation in preschool children. The malnutrition condition in children can be improved after S-ECC procedure under general anesthesia. Limited MR evidence does not support a correlation between genetic susceptibility to anesthesia and an increased risk for intelligence in children.

Prevalence and risk factors of depression and anxiety in primary care.

Introduction: Anxiety and depressive disorders are highly prevalent mental health conditions worldwide. However, little is known about their specific prevalence in primary care settings. This study aimed to determine the prevalence of depression and anxiety in the primary care population and identify associated patient characteristics. Method: We conducted a cross-sectional study using stratified sampling by age with a self-administered questionnaire survey in Singapore's National Health-care Group Polyclinics from December 2021 to April 2022. A total score of Patient Health Questionnaire-9 (PHQ-9) ≥10 represents clinical depression, and a total score of Generalised Anxiety Disorder-7 (GAD-7) ≥10 indicates clinical anxiety. Multivariable logistic regression was used to identify the factors associated with depression and anxiety. Results: A total of 5694 patients were approached and 3505 consented to the study (response rate=61.6%). There was a higher prevalence of coexisting clinical depression and anxiety (DA) (prevalence=5.4%) compared to clinical depression only (3.3%) and clinical anxiety only (1.9%). The odds of having DA were higher among those aged 21-39 years (odds ratio [OR] 13.49; 95% confidence interval [CI] 5.41-33.64) and 40-64 years (OR 2.28; 95% CI 1.03-5.03) compared to those ≥65 years. Women had higher odds of having DA (OR 2.33; 95% CI 1.54-3.50) compared to men. Respondents with diabetes had higher odds of having DA (OR 1.78; 95% CI 1.07-2.94) compared to those without diabetes. Conclusion: Coexisting clinical depression and anxiety are significantly present in the primary care setting, especially among younger individuals, patients with diabetes and women. Mental health screening programmes should include screening for both depression and anxiety, and target these at-risk groups.

An Asymmetric NIR-II Organic Fluorophore with an Ultra-Large Stokes Shift for Imaging-Guided and Targeted Phototherapy.

NIR-II imaging-guided phototherapy is an attractive, yet challenging, tumor treatment strategy. By monitoring the accumulation of phototherapy reagents at the tumor site through imaging and determining the appropriate therapy window, the therapeutic effect could be significantly improved. Probes with NIR-II (1000-1700 nm) fluorescence emission and a large Stokes shift hold great promise for fluorescence imaging with deep penetration, minimized self-quenching, and high spatiotemporal resolution. However, due to the lack of a suitable molecular framework, the design of a simple small-molecule dye with a large Stokes shift and NIR-II fluorescence emission has rarely been reported. Herein, we prepare an asymmetric D-π-A type NIR-II fluorescence probe (TBy). The probe is incapsulated in an amphiphilic polymer and modified with a fibronectin targeting peptide CREKA, which could recognize the fibrin-fibronectin complex overexpressed in multiple malignant tumors. The nanoparticles thus constructed (TByC-NPs) have maximum fluorescence emission at 1037 nm with a large Stokes shift of 426 nm, which is the largest Stokes shift among organic NIR-II fluorescent dyes reported in the literature. The TByC-NPs exhibit a good NIR-II imaging performance, active tumor targeting, and good photothermal and photodynamic capabilities. In vitro and in vivo studies verify that the TByC nanoplatform shows outstanding biocompatibility for NIR-II imaging-guided phototherapy and provides an excellent antitumor effect.

Fabrication of photo-induced molecular superoxide radical generator for highly efficient therapy against bacterial wound infection.

The pressing need for highly efficient antibacterial strategies arises from the prevalence of microbial biofilm infections and the emergence of rapidly evolving antibiotic-resistant strains of pathogenic bacteria. Photodynamic therapy represents a highly efficient and compelling antibacterial approach, offering promising prospects for effective control of the development of bacterial resistance. However, the effectiveness of many photosensitizers is limited due to the reduced generation of reactive oxygen species (ROS) in hypoxic microenvironment, which commonly occur in pathological conditions such as inflammatory and bacteria-infected wounds. Herein, we designed and prepared two phenothiazine-derived photosensitizers (NB-1 and NB-2), which can effectively generate superoxide anion radicals (O2●-) through the type I process. Both photosensitizers demonstrate significant efficacy in vitro for the eradication of broad-spectrum bacteria. Moreover, NB-2 possesses distinct advantages including strong membrane binding and strong generation of O2●-, rendering it an exceptionally efficient antibacterial agent against mature biofilms. In addition, laser activated NB-2 could be applied to treat MRSA-infected wound in vivo, which offers new opportunities for potential practical applications.

Research Progress of Baihe Gujin Decoction in the Treatment of Lung Cancer.

Baihe Gujin decoction is one of the most commonly used decoction in traditional Chinese medicine for the treatment of lung cancer. It can nourish yin and moisten the lung as well as prevent phlegm from forming and stop coughing. On the one hand, Baihe Gujin decoction is characterized with extensive application, proven efficacy, a long history, and high safety. On the other hand, Baihe Gujin decoction can induce apoptosis of tumor cells, improve immune function and inhibit inflammation. The main anti-tumor components of this include kaempferol, quercetin, isorhamnetin, glycyrrhizin and ß-sitosterol. Clinically, Baihe Gujin decoction can improve the adverse reactions caused by radiotherapy, chemotherapy and immunotherapy for lung cancer, enhance the quality of life of patients, and prolong their survival time. At present, there are a large number of clinical and basic researches on the treatment of lung cancer with Baihe Gujin decoction. In this paper, we mainly discussed the treatment of lung cancer with Baihe Gujin decoction through analyzing basic and clinical researches at home and abroad in the past 20 years. Through the discussion, we aimed to probe deeper into Baihe Gujin decoction for the treatment of lung cancer, thereby providing a broader idea for clinical diagnosis and treatment of lung cancer.

Integrated analysis of single cell-RNA sequencing and Mendelian randomization identifies lactate dehydrogenase B as a target of melatonin in ischemic stroke.

AIMS: Despite the success of single-cell RNA sequencing in identifying cellular heterogeneity in ischemic stroke, clarifying the mechanisms underlying these associations of differently expressed genes remains challenging. Several studies that integrate gene expression and gene expression quantitative trait loci (eQTLs) with genome wide-association study (GWAS) data to determine their causal role have been proposed. METHODS: Here, we combined Mendelian randomization (MR) framework and single cell (sc) RNA sequencing to study how differently expressed genes (DEGs) mediating the effect of gene expression on ischemic stroke. The hub gene was further validated in the in vitro model. RESULTS: We identified 2339 DEGs in 10 cell clusters. Among these DEGs, 58 genes were associated with the risk of ischemic stroke. After external validation with eQTL dataset, lactate dehydrogenase B (LDHB) is identified to be positively associated with ischemic stroke. The expression of LDHB has also been validated in sc RNA-seq with dominant expression in microglia and astrocytes, and melatonin is able to reduce the LDHB expression and activity in vitro ischemic models. CONCLUSION: Our study identifies LDHB as a novel biomarker for ischemic stroke via combining the sc RNA-seq and MR analysis.

A perylene diimide probe for NIR-II fluorescence imaging guided photothermal and type I/type II photodynamic synergistic therapy.

Phototherapy has garnered significant attention in the past decade. Photothermal and photodynamic synergistic therapy combined with NIR fluorescence imaging has been one of the most attractive treatment options because of the deep tissue penetration, high selectivity and excellent therapeutic effect. Benefiting from the superb photometrics and ease of modification, perylene diimide (PDI) and its derivatives have been employed as sensing probes and therapeutic agents in the biological and biomedical research fields, and exhibiting excellent potential. Herein, we reported the development of a novel organic small-molecule phototherapeutic agent, PDI-TN. The absorption of PDI-TN extends into the NIR region, which provides feasibility for NIR phototherapy. PDI-TN overcomes the traditional Aggregation-Caused Quenching (ACQ) effect and exhibits typical characteristics of Aggregation-Induced Emission (AIE). Subsequently, PDI-TN NPs were obtained by using an amphiphilic triblock copolymer F127 to encapsulate PDI-TN. Interestingly, the PDI-TN NPs not only exhibit satisfactory photothermal effects, but also can generate O2•- and 1O2 through type I and type II pathways, respectively. Additionally, the PDI-TN NPs emit strong fluorescence in the NIR-II region, and show outstanding therapeutic potential for in vivo NIR-II fluorescence imaging. To our knowledge, PDI-TN is the first PDI derivative used for NIR-II fluorescence imaging-guided photodynamic and photothermal synergistic therapy, which suggests excellent potential for future biological/biomedical applications.

RNA sequencing of the thalamus and rostral ventral medulla in rats with chronic orofacial pain.

Diagnosing and treating chronic orofacial pain is challenging due to its complex structure and limited understanding of its causes and mechanisms. In this study, we used RNA sequencing to identify differentially expressed genes (DEGs) in the rostral ventral medulla (RVM) and thalamus of rats with persistent orofacial pain, aiming to explore its development. DEGs were functionally analyzed using gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis. Results showed a significant association between immune response and pain in this model. Key DEG mRNA expression trends were further validated using real-time quantitative polymerase chain reaction (RT-PCR), confirming their crucial roles in chronic orofacial pain. After injecting complete Freund's adjuvant (CFA) into the bilateral temporomandibular joint cavity for 14 days, we observed 293 upregulated genes and 14 downregulated genes in the RVM, and 1086 upregulated genes and 37 downregulated genes in the thalamus. Furthermore, we identified 27 common DEGs with altered expression (upregulation) in both the thalamus and RVM, including Cd74, C3, Cxcl13, C1qb, Itgal, Fcgr2b, C5ar1, and Tlr2, which are pain-associated genes. Protein-protein interaction (PPI) analysis using Cytoscape revealed the involvement of Toll-like receptors, complement system, differentiation clusters, and antigen presentation-related proteins in the interaction between the thalamus and RVM. The results of this study show that the immune system seems to have a more significant influence on chronic orofacial pain. There may be direct or indirect influence between the thalamus and RVM, which may participate in the regulation of chronic orofacial pain.

Corrigendum: Virtual reality in managing dental pain and anxiety: a comprehensive review.

[This corrects the article DOI: 10.3389/fmed.2023.1285142.].

Ocular dominance-dependent binocular combination of monocular neuronal responses in macaque V1.

Primates rely on two eyes to perceive depth, while maintaining stable vision when either one eye or both eyes are open. Although psychophysical and modeling studies have investigated how monocular signals are combined to form binocular vision, the underlying neuronal mechanisms, particularly in V1 where most neurons exhibit binocularity with varying eye preferences, remain poorly understood. Here, we used two-photon calcium imaging to compare the monocular and binocular responses of thousands of simultaneously recorded V1 superficial-layer neurons in three awake macaques. During monocular stimulation, neurons preferring the stimulated eye exhibited significantly stronger responses compared to those preferring both eyes. However, during binocular stimulation, the responses of neurons preferring either eye were suppressed on the average, while those preferring both eyes were enhanced, resulting in similar neuronal responses irrespective of their eye preferences, and an overall response level similar to that with monocular viewing. A neuronally realistic model of binocular combination, which incorporates ocular dominance-dependent divisive interocular inhibition and binocular summation, is proposed to account for these findings.

Decorin suppresses stemness and migration potential of malignant peripheral nerve sheath tumor through inhibiting epidermal growth factor receptor signaling.

Cancer stem cells (CSCs) play pivotal roles in the growth, invasion, metastasis, chemo-resistance in malignant peripheral nerve sheath tumor (MPNST). The current characterization of CSCs in MPNST is not complete. Decorin is a critical regulator of microenvironment, but its expression and function in CSCs of MPNST has not been studied. In the current study, Decorin levels and its relationship with lung and liver metastasis were determined in clinical specimens. Decorin expression in CD133-positive or CD44-positive CSCs was analyzed by RT-qPCR on cytospun MPNST cells after flow cytometry-based cell sorting. Decorin-positive cells were separated from Decorin-negative cells in transfected MPNST cell lines using a designed plasmid expressing red fluorescent protein (RFP) under a Decorin promoter. Tumor sphere formation, tumor growth, cell invasion, cell migration, and the resistance to chemotherapy-induced apoptosis were determined on Decorin-positive versus Decorin-negative MPNST cells. In vivo tumor growth was analyzed in mice receiving subcutaneous transplantation of Decorin-positive versus Decorin-negative MPNSTs. We found that Decorin levels were significantly downregulated in MPNST specimens, compared to non-tumorous adjacent tissue. Significantly lower Decorin levels were detected in MPNSTs with lung or liver metastasis compared to those without. Poorer patient survival was detected in Decorin-low MPNST, compared to Decorin-high subjects. More Decorin-negative cells were detected in CD133-positive MPNST cells than CD133-negative MPNST cells, and in CD44-positive MPNST cells than in CD44-negative MPNST cells. Compared to Decorin-positive MPNST cells, Decorin-negative MPNST cells generated significantly more tumor spheres in culture, were more invasive and migratory, and were more resistant to chemotherapy-induced apoptosis, likely due to the inhibition of epidermal growth factor receptor signaling by Decorin. Decorin-negative MPNST cells grew significantly larger tumor in vivo. Thus, depletion of Decorin may occur in CSCs in MPNSTs, serving possibly as a new therapeutic target.

Single-cell sequencing analysis of chronic subdural hematoma cell subpopulations and their potential therapeutic mechanisms.

BACKGROUND: Chronic subdural hematoma (CSDH) is a prevalent form of intracranial haemorrhage encountered in neurosurgical practice, and its incidence has notably risen in recent years. Currently, there is a lack of studies that have comprehensively classified the cells present in hematomas removed during surgery, and their correlation with CSDH recurrence remains elusive. This study aims to analyse the subcellular populations and occupancy levels within peripheral blood. METHODS: This study analyses the subcellular populations and occupancy levels within peripheral blood and postoperatively removed hematomas by single-cell sequencing and attempts to analyse the effect of different cell occupancies within peripheral blood and intraoperatively removed hematomas on CSDH. RESULTS: The single-cell sequencing results showed that the cells were classified into 25 clusters by differential gene and UMAP dimensionality reduction clustering analyses and further classified into 17 significant cell populations by cell markers: pDCs, CD8 T cells, CD4 T cells, MigDCs, cDC2s, cDC1s, plasma cells, neutrophils, naive B cells, NK cells, memory B cells, M2 macrophages, CD8 Teffs, CD8 MAIT cells, CD4 Tregs, CD19 B cells, and monocytes. Further research showed that the presence of more cDC2 and M2 macrophages recruited at the focal site in patients with CSDH and the upregulation of the level of T-cell occupancy may be a red flag for further brain damage. ROS, a marker of oxidative stress, was significantly upregulated in cDC2 cells and may mediate the functioning of transcription proteins of inflammatory factors, such as NFκB, which induced T cells' activation. Moreover, cDC2 may regulate M2 macrophage immune infiltration and anti-inflammatory activity by secreting IL1ß and binding to M2 macrophage IL1R protein. CONCLUSION: The detailed classification of cells in the peripheral blood and hematoma site of CSDH patients helps us to understand the mechanism of CSDH generation and the reduction in the probability of recurrence by regulating the ratio of cell subpopulations.

Rational Design of FeCo-S/Ni2P/NF Heterojunction as a Robust Electrocatalyst for Water Splitting.

The rational design of nonnoble-metal-based catalysts with high electroactivity and long-term stability, featuring controllable active sites, remains a significant challenge for achieving effective water electrolysis. Herein, a heterogeneous catalyst with a FeCo-S and Ni2P heterostructure (denoted FeCo-S/Ni2P/NF) grown on nickel foam (NF) was synthesized by a solvothermal method and low-temperature phosphorization. The FeCo-S/Ni2P/NF catalyst shows excellent electrocatalytic performance and stability in alkaline solution. The FeCo-S/Ni2P/NF catalyst demonstrates low overpotentials (η) for both the hydrogen evolution reaction (HER) (49 mV@10 mA cm-2) and the oxygen evolution reaction (OER) (279 mV@100 mA cm-2). Assembling the FeCo-S/Ni2P/NF catalyst as both cathode and anode in an electrolytic cell for overall water splitting (OWS) needs an ultralow cell voltage of 1.57 V to attain a current density (CD) of 300 mA cm-2. Furthermore, it demonstrates excellent durability, significantly outperforming the commercial Pt/C∥IrO2 system. The results of experiments indicate that the heterostructure and synergistic effect of FeCo-S and Ni2P can significantly enhance conductivity, facilitate mass/ion transport and gas evolution, and expose more active sites, thereby improving the catalytic activity of the electrocatalyst for the OWS. This study provides a rational approach for the development of commercially promising dual-functional electrocatalysts.

The Use of E-Learning in Peyton's 4-Step Approach: Evaluation of Facial Computed Tomography Scans.

Imparting procedural skills is challenging. Peyton's approach is an effective face-to-face teaching technique increasingly used in complex skills training. Institutions are beginning to incorporate online training as part of their procedural curriculum. We developed E-Peyton's to employ Peyton's approach through an electronic learning platform. The efficacy of E-Peyton's approach in teaching the interpretation of facial computed tomography (CT) scans is evaluated in this study. Naïve learners (n=41) were randomized into 2 groups based on teaching techniques employed: E-Peyton's (n=20) and Peyton's (n=21) approaches. The distance between the infraorbital margin and the posterior ledge was measured using a 3-part standardized measuring protocol on OsiriX. Twenty measurements were assessed for accuracy against the benchmark (±2 mm) at week 0 and week 1. Training durations were compared. Questionnaires were administered before and after the study to identify learners' acceptance of teaching techniques and their confidence in interpreting facial CT scans. Learners in both teaching techniques had comparable skills retention. Gap scores indicate significant improvement in learner's confidence levels regardless of teaching technique (P<0.05). Both teaching techniques were well-accepted by learners. E-Peyton's and Peyton's approaches required a similar training duration. The COVID-19 pandemic highlights the importance of effective remote learning platforms. E-Peyton's approach is comparable to that of Peyton's in all areas of assessment. E-Peyton's approach effectively automates Peyton's approach, allowing for standardized, high-quality procedural skills training while reducing manpower burden.

One-Step Dual-Color Labeling of Viral Envelope and Intraviral Genome with Quantum Dots Harnessing Virus Infection.

Labeling the genome and envelope of a virus with multicolor quantum dots (QDs) simultaneously enables real-time monitoring of viral uncoating and genome release, contributing to our understanding of virus infection mechanisms. However, current labeling techniques require genetic modification, which alters the virus's composition and infectivity. To address this, we utilized the CRISPR/Cas13 system and a bioorthogonal metabolic method to label the Japanese encephalitis virus (JEV) genome and envelopes with different-colored QDs in situ. This technique allows one-step two-color labeling of the viral envelope and intraviral genome with QDs harnessing virus infection. In combination with single-virus tracking, we visualized JEV uncoating and genome release in real time near the endoplasmic reticulum of live cells. This labeling strategy allows for real-time visualization of uncoating and genome release at the single-virus level, and it is expected to advance the study of other viral infection mechanisms.

Autoinhibition and activation of myosin VI revealed by its cryo-EM structure.

Myosin VI is the only molecular motor that moves towards the minus end along actin filaments. Numerous cellular processes require myosin VI and tight regulations of the motor's activity. Defects in myosin VI activity are known to cause genetic diseases such as deafness and cardiomyopathy. However, the molecular mechanisms underlying the activity regulation of myosin VI remain elusive. Here, we determined the high-resolution cryo-electron microscopic structure of myosin VI in its autoinhibited state. Our structure reveals that autoinhibited myosin VI adopts a compact, monomeric conformation via extensive interactions between the head and tail domains, orchestrated by an elongated single-α-helix region resembling a "spine". This autoinhibited structure effectively blocks cargo binding sites and represses the motor's ATPase activity. Certain cargo adaptors such as GIPC can release multiple inhibitory interactions and promote motor activity, pointing to a cargo-mediated activation of the processive motor. Moreover, our structural findings allow rationalization of disease-associated mutations in myosin VI. Beyond the activity regulation mechanisms of myosin VI, our study also sheds lights on how activities of other myosin motors such as myosin VII and X might be regulated.