Association Between Oral Health and Airflow Limitation: Analysis Using a Nationwide Survey in Korea.

BACKGROUND: Although poor oral health is a common comorbidity in individuals with airflow limitation (AFL), few studies have comprehensively evaluated this association. Furthermore, the association between oral health and the severity of AFL has not been well elucidated. METHODS: Using a population-based nationwide survey, we classified individuals according to the presence or absence of AFL defined as pre-bronchodilator forced expiratory volume in 1 second/forced vital capacity < 0.7. Using multivariable logistic regression analyses, we evaluated the association between AFL severity and the number of remaining teeth; the presence of periodontitis; the Decayed, Missing, and Filled Teeth (DMFT) index; and denture wearing. RESULTS: Among the 31,839 participants, 14% had AFL. Compared with the control group, the AFL group had a higher proportion of periodontitis (88.8% vs. 79.4%), complete denture (6.2% vs. 1.6%), and high DMFT index (37.3% vs. 27.8%) (P < 0.001 for all). In multivariable analyses, denture status: removable partial denture (adjusted odds ratio [aOR], 1.12; 95% confidence interval [95% CI], 1.04-1.20) and complete denture (aOR, 1.52; 95% CI, 1.01-2.05), high DMFT index (aOR, 1.13; 95% CI, 1.02-1.24), and fewer permanent teeth (0-19; aOR, 1.32; 95% CI, 1.12-1.52) were significantly associated with AFL. Furthermore, those with severe to very severe AFL had a significantly higher proportion of complete denture (aOR, 2.41; 95% CI, 1.11-3.71) and fewer remaining teeth (0-19; aOR, 2.29; 95% CI, 1.57-3.01). CONCLUSION: Denture wearing, high DMFT index, and fewer permanent teeth are significantly associated with AFL. Furthermore, a reduced number of permanent teeth (0-19) was significantly related to the severity of AFL. Therefore, physicians should pay attention to oral health in managing patients with AFL, such as chronic obstructive pulmonary disease.

Altered Lung Heat Shock Protein-70 Expression and Severity of Sepsis-Induced Acute Lung Injury in a Chronic Kidney Disease Rat Model.

Enhanced heat shock protein-70 (HSP-70) expression in the lungs is associated with attenuated acute lung injury (ALI) in a sepsis model. Chronic kidney disease (CKD) significantly contributes to the poor prognosis of patients with sepsis. This study examined the relationship between sepsis-induced ALI severity and altered lung HSP-70 expression in CKD. Experimental rats underwent a sham operation (control group) or 5/6 nephrectomy (CKD group). Sepsis was induced with cecal ligation and puncture (CLP). Laboratory tests and lung harvest were performed in the control group (without CLP and after 3, 12, 24, and 72 h of CLP) and in the CKD group (without CLP and after 72 h of CLP). ALI was the most severe after 12 h of sepsis. The mean lung injury score at 72 h after sepsis was significantly higher in the CKD group than in the control group (4.38 versus 3.30, p < 0.01). Nonetheless, enhanced lung HSP-70 expression was not observed in the CKD group. This study shows that altered lung HSP-70 expression is associated with the worsening of sepsis-induced ALI in patients with CKD. Enhancing lung HSP-70 is a novel treatment target for patients with CKD and sepsis-induced ALI.

Evaluation of the Antiviral Efficacy of Subcutaneous Nafamostat Formulated with Glycyrrhizic Acid against SARS-CoV-2 in a Murine Model.

The ongoing COVID-19 pandemic highlights the urgent need for effective antiviral agents and vaccines. Drug repositioning, which involves modifying existing drugs, offers a promising approach for expediting the development of novel therapeutics. In this study, we developed a new drug, MDB-MDB-601a-NM, by modifying the existing drug nafamostat (NM) with the incorporation of glycyrrhizic acid (GA). We assessed the pharmacokinetic profiles of MDB-601a-NM and nafamostat in Sprague-Dawley rats, revealing rapid clearance of nafamostat and sustained drug concentration of MDB-601a-NM after subcutaneous administration. Single-dose toxicity studies showed potential toxicity and persistent swelling at the injection site with high-dose administration of MDB-601a-NM. Furthermore, we evaluated the efficacy of MDB-601a-NM in protecting against SARS-CoV-2 infection using the K18 hACE-2 transgenic mouse model. Mice treated with 60 mg/kg and 100 mg/kg of MDB-601a-NM exhibited improved protectivity in terms of weight loss and survival rates compared to the nafamostat-treated group. Histopathological analysis revealed dose-dependent improvements in histopathological changes and enhanced inhibitory efficacy in MDB-601a-NM-treated groups. Notably, no viral replication was detected in the brain tissue when mice were treated with 60 mg/kg and 100 mg/kg of MDB-601a-NM. Our developed MDB-601a-NM, a modified Nafamostat with glycyrrhizic acid, shows improved protectivity against SARS-CoV-2 infection. Its sustained drug concentration after subcutaneous administration and dose-dependent improvements makes it a promising therapeutic option.

Adenomatous polyposis coli-stimulated GEF 1 (Asef1) is a negative regulator of excitatory synaptic function.

Guanine nucleotide exchange factors (GEFs) play important roles in many cellular processes, including regulation of the structural plasticity of dendritic spines. A GEF protein, adenomatous polyposis coli-stimulated GEF 1 (Asef1, ARHGEF4) is highly expressed in the nervous system. However, the function of Asef1 has not been investigated in neurons. Here, we present evidence showing that Asef1 negatively regulates the synaptic localization of postsynaptic density protein 95 (PSD-95) in the excitatory synapse by inhibiting Staufen-mediated synaptic localization of PSD-95. Accordingly, Asef1 expression impairs synaptic transmission in hippocampal cultured neurons. In addition, neuronal activity facilitates the dissociation of Asef1 from Staufen in a phosphoinositide 3 kinase (PI3K)-dependent manner. Taken together, our data reveal Asef1 functions as a negative regulator of synaptic localization of PSD-95 and synaptic transmission.

NOTCH1 intracellular domain negatively regulates PAK1 signaling pathway through direct interaction.

p21-Activated kinase 1 (PAK1) is a serine/threonine protein kinase implicated in cytoskeletal remodeling and cell motility. Recent studies have shown that it also promotes cell proliferation, regulates apoptosis, and increases cell transformation and invasion. In this study, we showed that NOTCH1 intracellular domain (NOTCH1-IC) negatively regulated PAK1 signaling pathway. We found a novel interaction between NOTCH1-IC and PAK1. Overexpression of NOTCH1-IC decreased PAK1-induced integrin-linked kinase 1 (ILK1) phosphorylation, whereas inhibition of NOTCH1 signaling increased PAK1-induced ILK1 phosphorylation. Notably, ILK1 phosphorylation was higher in PS1,2(-/-) cells than in PS1,2(+/+) cells. As expected, overexpression of NOTCH1-IC decreased ILK1-induced phosphorylation of glycogen synthase kinase 3 beta (GSK-3beta). Furthermore, NOTCH1-IC disrupted the interaction of PAK1 with ILK1 and altered PAK1 localization by directly interacting with it. This inhibitory effect of NOTCH1-IC on the PAK1 signaling pathway was mediated by the binding of NOTCH1-IC to PAK1 and by the alteration of PAK1 localization. Together, these results suggest that NOTCH1-IC is a new regulator of the PAK1 signaling pathway that directly interacts with PAK1 and regulates its shuttling between the nucleus and the cytoplasm.

Growth and Pathogenic Potential of Naturally Selected Reassortants after Coinfection with Pandemic H1N1 and Highly Pathogenic Avian Influenza H5N1 Viruses.

Coinfection of ferrets with H5N1 and pH1N1 viruses resulted in two predominate genotypes in the lungs containing surface genes of highly pathogenic avian influenza H5N1 virus in the backbone of pandemic H1N1 2009 (pH1N1). Compared to parental strains, these reassortants exhibited increased growth and virulence in vitro and in mice but failed to be transmitted indirectly to naive contact ferrets. Thus, this demonstrates a possible natural reassortment following coinfection as well as the pathogenicity of the potential reassortants.

TRPV1 on astrocytes rescues nigral dopamine neurons in Parkinson's disease via CNTF.

Currently there is no neuroprotective or neurorestorative therapy for Parkinson's disease. Here we report that transient receptor potential vanilloid 1 (TRPV1) on astrocytes mediates endogenous production of ciliary neurotrophic factor (CNTF), which prevents the active degeneration of dopamine neurons and leads to behavioural recovery through CNTF receptor alpha (CNTFRα) on nigral dopamine neurons in both the MPP(+)-lesioned or adeno-associated virus α-synuclein rat models of Parkinson's disease. Western blot and immunohistochemical analysis of human post-mortem substantia nigra from Parkinson's disease suggests that this endogenous neuroprotective system (TRPV1 and CNTF on astrocytes, and CNTFRα on dopamine neurons) might have relevance to human Parkinson's disease. Our results suggest that activation of astrocytic TRPV1 activates endogenous neuroprotective machinery in vivo and that it is a novel therapeutic target for the treatment of Parkinson's disease.

FRMD6 determines the cell fate towards senescence: involvement of the Hippo-YAP-CCN3 axis.

Cellular senescence, a hallmark of aging, is pathogenically linked to the development of aging-related diseases. This study demonstrates that FRMD6, an upstream component of the Hippo/YAP signaling cascade, is a key regulator of senescence. Proteomic analysis revealed that FRMD6 is upregulated in senescent IMR90 fibroblasts under various senescence-inducing conditions. Silencing FRMD6 mitigated the senescence of IMR90 cells, suggesting its requirement in senescence. Conversely, the overexpression of FRMD6 alone induced senescence in cells and in lung tissue, establishing a causal link. The elevated FRMD6 levels correlated well with increased levels of the inhibitory phosphorylated YAP/TAZ. We identified cellular communication network factor 3 (CCN3), a key component of the senescence-associated secretory phenotype regulated by YAP, whose administration attenuated FRMD6-induced senescence in a dose-dependent manner. Mechanistically, FRMD6 interacted with and activated MST kinase, which led to YAP/TAZ inactivation. The expression of FRMD6 was regulated by the p53 and SMAD transcription factors in senescent cells. Accordingly, the expression of FRMD6 was upregulated by TGF-ß treatment that activates those transcription factors. In TGF-ß-treated IMR90 cells, FRMD6 mainly segregated with p21, a senescence marker, but rarely segregated with α-SMA, a myofibroblast marker, which suggests that FRMD6 has a role in directing cells towards senescence. Similarly, in TGF-ß-enriched environments, such as fibroblastic foci (FF) from patients with idiopathic pulmonary fibrosis, FRMD6 co-localized with p16 in FF lining cells, while it was rarely detected in α-SMA-positive myofibroblasts that are abundant in FF. In sum, this study identifies FRMD6 as a novel regulator of senescence and elucidates the contribution of the FRMD6-Hippo/YAP-CCN3 axis to senescence.

Mammalian adaptation risk in HPAI H5N8: a comprehensive model bridging experimental data with mathematical insights.

Understanding the mammalian pathogenesis and interspecies transmission of HPAI H5N8 virus hinges on mapping its adaptive markers. We used deep sequencing to track these markers over five passages in murine lung tissue. Subsequently, we evaluated the growth, selection, and RNA load of eight recombinant viruses with mammalian adaptive markers. By leveraging an integrated non-linear regression model, we quantitatively determined the influence of these markers on growth, adaptation, and RNA expression in mammalian hosts. Furthermore, our findings revealed that the interplay of these markers can lead to synergistic, additive, or antagonistic effects when combined. The elucidation distance method then transformed these results into distinct values, facilitating the derivation of a risk score for each marker. In vivo tests affirmed the accuracy of scores. As more mutations were incorporated, the overall risk score of virus heightened, and the optimal interplay between markers became essential for risk augmentation. Our study provides a robust model to assess risk from adaptive markers of HPAI H5N8, guiding strategies against future influenza threats.

Impacts of regular physical activity on hospitalisation in chronic obstructive pulmonary disease: a nationwide population-based study.

INTRODUCTION: Studies that comprehensively evaluate the association between physical activity (PA) levels, particularly by quantifying PA intensity, and healthcare use requiring emergency department (ED) visit or hospitalisation in patients with chronic obstructive pulmonary disease (COPD) are limited in Korea. METHODS: The risk of all-cause and respiratory ED visit or hospitalisation according to the presence or absence of COPD and the level of PA was evaluated in a retrospective nationwide cohort comprising 3308 subjects with COPD (COPD cohort) and 293 358 subjects without COPD (non-COPD cohort) from 2009 to 2017. RESULTS: The COPD group exhibited a higher relative risk of all-cause and respiratory ED visit or hospitalisation across all levels of PA compared with the highly active control group (≥1500 metabolic equivalents (METs)-min/week). Specifically, the highest risk was observed in the sedentary group (adjusted HR (aHR) (95% CI) = 1.70 (1.59 to 1.81) for all-cause ED visit or hospitalisation, 5.45 (4.86 to 6.12) for respiratory ED visit or hospitalisation). A 500 MET-min/week increase in PA was associated with reductions in all-cause and respiratory ED visit or hospitalisation in the COPD cohort (aHR (95% CI) = 0.92 (0.88 to 0.96) for all-cause, 0.87 (0.82 to 0.93) for respiratory cause). CONCLUSIONS: Compared with the presumed healthiest cohort, the control group with PA>1500 METs-min/week, the COPD group with reduced PA has a higher risk of ED visit or hospitalisation.

pSlugS158 Immunohistochemistry is Useful in Grading Meningioma.

Snail family transcriptional repressor 2 (SNAI2, Slug) is a transcription factor that belong to the Slug/Snail superfamily. Site specific phosphorylation of slug (pSlugS158) is detected during the M phase, and thus, this phosphorylated protein is considered a novel marker for detecting mitotic figures. Herein, we investigated whether the detection of mitosis using pSlugS158 expression can be used in the histological grading of meningioma. We performed immunohistochemistry for pSlugS158 and PHH3 in tissue samples of 61 patients with meningioma and examined the association between mitotic counts using pSlugS158 and recurrence-free survival (RFS). The nuclear expression of pSlugS158 was observed in the cell with mitotic figures. Tumor grading based on pSlugS158 was significantly associated with the RFS (p < .001). It can be concluded that pSlugS158 is a useful and practical marker to detect mitosis and seems to be reliable for the counting of mitoses in histological grading of meningioma.

Regorafenib prevents the development of emphysema in a murine elastase model.

Emphysema is a chronic obstructive lung disease characterized by inflammation and enlargement of the air spaces. Regorafenib, a potential senomorphic drug, exhibited a therapeutic effect in porcine pancreatic elastase (PPE)-induced emphysema in mice. In the current study we examined the preventive role of regorafenib in development of emphysema. Lung function tests and morphometry showed that oral administration of regorafenib (5 mg/kg/day) for seven days after instillation of PPE resulted in attenuation of emphysema. Mechanistically, regorafenib reduced the recruitment of inflammatory cells, particularly macrophages and neutrophils, in bronchoalveolar lavage fluid. In agreement with these findings, measurements using a cytokine array and ELISA showed that expression of inflammatory mediators including interleukin (IL)-1ß, IL-6, and CXCL1/KC, and tissue inhibitor of matrix metalloprotease-1 (TIMP-1), was downregulated. The results of immunohistochemical analysis confirmed that expression of IL-6, CXCL1/KC, and TIMP-1 was reduced in the lung parenchyma. Collectively, the results support the preventive role of regorafenib in development of emphysema in mice and provide mechanistic insights into prevention strategies. [BMB Reports 2023; 56(8): 439-444].

Evaluating Z-FA-FMK, a host cathepsin L protease inhibitor, as a potent and broad-spectrum antiviral therapy against SARS-CoV-2 and related coronaviruses.

Even though the World Health Organization announced the end of the COVID-19 pandemic as a global public health emergency on May 5, 2023, SARS-CoV-2 continues to pose a significant health threat worldwide, resulting in substantial numbers of infections and fatalities. This study investigated the antiviral potential of Z-FA-FMK (FMK), a novel host cathepsin L protease inhibitor, against SARS-CoV-2 infection using both in vitro and in vivo models. In vitro assessments of FMK against a diverse set of SARS-CoV-2 strains, including the Wuhan-like strain and nine variants, demonstrated potent inhibition with EC50 values ranging from 0.55 to 2.41 µM, showcasing similar or superior efficacy compared to FDA-approved antivirals nirmatrelvir (NTV) and molnupiravir (MPV). In vivo experiments using orally administered FMK (25 mg/kg) in SARS-CoV-2-infected K18 hACE2 transgenic mice revealed improved survival rates of 60% and accelerated recovery compared to NTV and MPV treatments. Additionally, FMK displayed a longer half-life (17.26 ± 8.89 h) than NTV and MPV in the mouse model. Due to its host-targeting mechanism, FMK offers potential advantages such as reduced drug resistance and broad-spectrum antiviral activity against multiple coronaviruses. These findings indicate that FMK may serve as a promising candidate for further clinical evaluation in the fight against SARS-CoV-2.

Defining regorafenib as a senomorphic drug: therapeutic potential in the age-related lung disease emphysema.

Senescence, a hallmark of aging, is a factor in age-related diseases (ARDs). Therefore, targeting senescence is widely regarded as a practicable method for modulating the effects of aging and ARDs. Here, we report the identification of regorafenib, an inhibitor of multiple receptor tyrosine kinases, as a senescence-attenuating drug. We identified regorafenib by screening an FDA-approved drug library. Treatment with regorafenib at a sublethal dose resulted in effective attenuation of the phenotypes of ßPIX knockdown- and doxorubicin-induced senescence and replicative senescence in IMR-90 cells; cell cycle arrest, and increased SA-ß-Gal staining and senescence-associated secretory phenotypes, particularly increasing the secretion of interleukin 6 (IL-6) and IL-8. Consistent with this result, slower progression of ßPIX depletion-induced senescence was observed in the lungs of mice after treatment with regorafenib. Mechanistically, the results of proteomics analysis in diverse types of senescence indicated that growth differentiation factor 15 and plasminogen activator inhibitor-1 are shared targets of regorafenib. Analysis of arrays for phospho-receptors and kinases identified several receptor tyrosine kinases, including platelet-derived growth factor receptor α and discoidin domain receptor 2, as additional targets of regorafenib and revealed AKT/mTOR, ERK/RSK, and JAK/STAT3 signaling as the major effector pathways. Finally, treatment with regorafenib resulted in attenuation of senescence and amelioration of porcine pancreatic elastase-induced emphysema in mice. Based on these results, regorafenib can be defined as a novel senomorphic drug, suggesting its therapeutic potential in pulmonary emphysema.

Characteristics and intrasubject variation in the respiratory microbiome in interstitial lung disease.

Recent studies have reported that the lower airway microbiome may play an essential role in the development and progression of interstitial lung disease (ILD). The aim of the current study was to evaluate the characteristics of the respiratory microbiome and intrasubject variation in patients with ILD. Patients with ILD were recruited prospectively for 12 months. The sample size was small (n = 11) owing to delayed recruitment during the COVID-19 pandemic. All subjects were hospitalized and were evaluated by a questionnaire survey, blood sampling, pulmonary function test, and bronchoscopy. Bronchoalveolar lavage fluid (BALF) was obtained at 2 sites, the most and least disease-affected lesions. Sputum collection was also performed. Furthermore, 16S ribosomal RNA gene sequencing was performed using the Illumina platform and indexes of α- and ß-diversity were evaluated. Species diversity and richness tended to be lower in the most-affected lesion than in the least-affected lesion. However, taxonomic abundance patterns were similar in these 2 groups. The phylum Fusobacteria was more prevalent in fibrotic ILD than in nonfibrotic ILD. Inter-sample differences in relative abundances were more prominent in BALF versus sputum specimens. Rothia and Veillonella were more prevalent in the sputum than in BALF. We did not detect site-specific dysbiosis in the ILD lung. BALF was an effective respiratory specimen type for evaluating the lung microbiome in patients with ILD. Further studies are needed to evaluate the causal links between the lung microbiome and the pathogenesis of ILD.

Safety and efficacy of remimazolam compared with midazolam during bronchoscopy: a single-center, randomized controlled study.

Although remimazolam is an ultra-short-acting benzodiazepine with a shorter elimination half-life and faster recovery time than midazolam, studies evaluating its safety and efficacy during bronchoscopy are limited. This study aimed to compare the safety and efficacy of remimazolam with those of midazolam for bronchoscopy. This prospective randomized parallel-group study was conducted at a single institution. The primary outcome was the time from the end of the procedure to full alertness. Other procedural time parameters, satisfaction profiles, and adverse effects were thoroughly evaluated. The time taken to reach peak sedation and the time from the end of the procedure to full alertness was significantly shorter in the remimazolam group than in the midazolam group (median [interquartile range], 2 min [1-4] vs. 3 min [2-5], P = 0.006; and median, 2 min [1-5] vs. 5 min [1-12], P = 0.035, respectively). In patients with non-biopsy procedures (n = 79), participant satisfaction was significantly higher in the remimazolam group than in the midazolam group (median rated scale, 10 vs. 7, P = 0.042). Physician satisfaction and willingness to repeat the procedure were similar between groups. Although the incidence of adverse effects was similar between the groups and there was no significant difference, the midazolam group had a higher antidote administration rate than the remimazolam group (15.7% vs. 4.1%, P = 0.092). Remimazolam is effective and safe for achieving adequate sedation, with a shorter onset time and faster neuropsychiatric recovery than midazolam. It may be a new option for sedation during bronchoscopy.Trial registration: The trial registration number is NCT05994547, and the date of first registration is 16/08/2023.

Systemic sclerosis and risk of bronchiectasis: a nationwide longitudinal cohort study.

BACKGROUND: The association between systemic sclerosis and the development of bronchiectasis is unclear. This study aimed to compare the risk of bronchiectasis between individuals with systemic sclerosis and those without using a nationwide longitudinal dataset. METHODS: Using the Korean National Health Insurance Service dataset between 2010 and 2017, we identified 4845 individuals aged ≥ 20 years with systemic sclerosis and 24,225 without systemic sclerosis who were matched 1:5 by age and sex. They were followed up until the date of a bronchiectasis diagnosis, death, or December 31, 2019, whichever came first. RESULTS: During a median follow-up period of 6.0 (interquartile range, 3.2-8.7) years, 5.3% of the systemic sclerosis cohort and 1.9% of the matched cohort developed bronchiectasis, with incidence rates of 9.99 and 3.23 per 1000 person-years, respectively. Even after adjusting for potential confounders, the risk of incident bronchiectasis was significantly higher in the systemic sclerosis cohort than in the matched cohort (adjusted hazard ratio 2.63, 95% confidence interval 2.22-3.12). A subgroup analysis of individuals with systemic sclerosis revealed that the risk of incident bronchiectasis was notably higher in younger individuals aged 20-39 years (P for interaction = 0.048) and in those without other coexisting connective tissue diseases (P for interaction = 0.006) than in their counterparts. CONCLUSIONS: The risk of incident bronchiectasis is higher in individuals with systemic sclerosis than those without. Bronchiectasis should be considered one of the pulmonary manifestations related to systemic sclerosis.

Influenza vaccination trend and related factors among patients with diabetes in Korea: Analysis using a nationwide database.

Background: Subjects with diabetes are at higher risk of serious influenza-related complications. We aimed to investigate the yearly trend of influenza vaccination and factors associated with being unvaccinated for influenza in subjects with diabetes using a nationwide observational study performed within the recent decade. Methods: Among 105,732 subjects from the Korea National Health and Nutrition Examination Survey between 2007 and 2019, 8,632 with diabetes were included. We investigated the yearly trend of influenza vaccination and factors associated with being unvaccinated for influenza. Results: During the study period, the prevalence of influenza vaccination in subjects with diabetes showed a tendency to increase every year, reaching almost 60% in 2019, which was higher than the rate in subjects without diabetes. Younger age (adjusted hazard ratio (aHR) [95% CI] 11.29 [8.63-14.75] for < 50 years; 6.16 [5.21-7.29] for 50-65 years), male (aHR 1.67 [1.52-1.87]), current smoker (aHR 1.31 [1.00-1.72], lower-income status (aHR 1.46 [1.17, 1.84]), and high education level (aHR 1.30 [1.01-1.67]) were associated with being unvaccinated. Also, a poorer glycemic control with HbA1c ≥ 9% was found to be correlated with unvaccinated status (aHR 1.48 [1.15-1.90]). Conclusion: The influenza vaccination rate is still unsatisfactory in subjects with diabetes. Young age, males, low-income level, high education level, and poor glycemic control were associated with unvaccinated status. Considering the risk-benefits of influenza vaccination in patients with diabetes, physicians should make an effort to increase vaccination rates, especially in low vaccination rate groups.

A Rapid Method for Generating Infectious SARS-CoV-2 and Variants Using Mutagenesis and Circular Polymerase Extension Cloning.

The appearance of SARS-CoV-2 variants in late 2020 raised alarming global public health concerns. Despite continued scientific progress, the genetic profiles of these variants bring changes in viral properties that threaten vaccine efficacy. Thus, it is critically important to investigate the biologic profiles and significance of these evolving variants. In this study, we demonstrate the application of circular polymerase extension cloning (CPEC) to the generation of full-length clones of SARS-CoV-2. We report that, combined with a specific primer design scheme, this yields a simpler, uncomplicated, and versatile approach for engineering SARS-CoV-2 variants with high viral recovery efficiency. This new strategy for genomic engineering of SARS-CoV-2 variants was implemented and evaluated for its efficiency in generating point mutations (K417N, L452R, E484K, N501Y, D614G, P681H, P681R, Δ69-70, Δ157-158, E484K+N501Y, and Ins-38F) and multiple mutations (N501Y/D614G and E484K/N501Y/D614G), as well as a large truncation (ΔORF7A) and insertion (GFP). The application of CPEC to mutagenesis also allows the inclusion of a confirmatory step prior to assembly and transfection. This method could be of value in the molecular characterization of emerging SARS-CoV-2 variants as well as the development and testing of vaccines, therapeutic antibodies, and antivirals. IMPORTANCE Since the first emergence of the SARS-CoV-2 variant in late 2020, novel variants have been continuously introduced to the human population, causing severe public health threats. In general, because these variants acquire new genetic mutation/s, it is critical to analyze the biological function of viruses that such mutations can confer. Therefore, we devised a method that can construct SARS-CoV-2 infectious clones and their variants rapidly and efficiently. The method was developed based on a PCR-based circular polymerase extension cloning (CPEC) combined with a specific primer design scheme. The efficiency of the newly designed method was evaluated by generating SARS-CoV-2 variants with single point mutations, multiple point mutations, and a large truncation and insertion. This method could be of value for the molecular characterization of emerging SARS-CoV-2 variants and the development and testing of vaccines and antiviral agents.

The TGFß→TAK1→LATS→YAP1 Pathway Regulates the Spatiotemporal Dynamics of YAP1.

The Hippo kinase cascade functions as a central hub that relays input from the "outside world" of the cell and translates it into specific cellular responses by regulating the activity of Yes-associated protein 1 (YAP1). How Hippo translates input from the extracellular signals into specific intracellular responses remains unclear. Here, we show that transforming growth factor ß (TGFß)-activated TAK1 activates LATS1/2, which then phosphorylates YAP1. Phosphorylated YAP1 (p-YAP1) associates with RUNX3, but not with TEAD4, to form a TGFß-stimulated restriction (R)-point-associated complex which activates target chromatin loci in the nucleus. Soon after, p-YAP1 is exported to the cytoplasm. Attenuation of TGFß signaling results in re-localization of unphosphorylated YAP1 to the nucleus, where it forms a YAP1/TEAD4/SMAD3/AP1/p300 complex. The TGFß-stimulated spatiotemporal dynamics of YAP1 are abrogated in many cancer cells. These results identify a new pathway that integrates TGFß signals and the Hippo pathway (TGFß→TAK1→LATS1/2→YAP1 cascade) with a novel dynamic nuclear role for p-YAP1.