AQP5 promotes epithelial-mesenchymal transition and tumor growth through activating the Wnt/ß-catenin pathway in triple-negative breast cancer.

BACKGROUND: Emerging data identifies aquaporin 5 (AQP5) as a vital player in many kinds of cancers. Over expression of AQP5 was associated with increased metastasis and poor prognosis, suggesting that AQP5 may facilitate cancer cell proliferation and migration. Our previous studies also showed that AQP3 and AQP5 were highly expressed in triple-negative breast cancer (TNBC) and the expression of AQP3 and AQP5 in TNBC tissue was positive correlated with advanced clinical stage. OBJECTIVE: We aim to investigate the role of AQP5 in TNBC oncogenesis and development. METHODS: MDA-MB-231 cells were transfected with siRNA-AQP5 and AQP5 overexpression vector to establish a differential expression system for AQP5. Cell proliferation and apoptosis of MDA-MB-231 cells were detected by CCK-8 (Cell Counting Kit-8) and FCM (flow cytometry), respectively. Cell migration and invasion abilities were evaluated by wound healing assay and transwell assay. The qRT-PCR and western blot assays were used to study the effect of AQP5 expression level on the expression of epithelial-to-mesenchymal transition (EMT) related molecules. The effects of ICG-001, a Wnt/ß-catenin signaling pathway inhibitor, on the invasive and migratory capabilities of overexpressed AQP5 cells and downstream molecules were measured. RESULTS: 1. The expression of AQP5 in the MDA-MB-231 cells was significantly higher than that in the MCF-10A cells. 2. Up-regulation of AQP5 significantly promoted the proliferation, migration and invasion of TNBC cells, while inhibited the cell apoptosis; in addition, up-regulation of AQP5 increased the expression of Bcl-2 and decreased the expression of Caspase-3. However, knockdown of AQP5 presented the adverse effects of AQP5 overexpression. 3. Overexpressed AQP5 induced the overexpression of EMT-related factors, which further promoted the migration and invasion of cells. 4. Overexpression of AQP5 could up-regulate the expression of ß-catenin in the nucleus followed by increasing the expression levels of downstream genes in Wnt/ß-catenin signaling pathway. Moreover, ICG-001, the inhibitor of Wnt/ß-catenin signaling pathway, could significantly attenuate the effect of overexpression of AQP5 on cells, further confirming that AQP5 may promote the proliferation, migration and invasion of TNBC cells by activating Wnt/ß-catenin signaling pathway. CONCLUSIONS: In the TNBC cells, AQP5 modulates the expression levels of EMT-related proteins through activation of Wnt/ß-catenin signaling pathway, thus enhancing the cell proliferation, migration and invasion while inhibiting the cell apoptosis.

The Worries of Out-of-Home Activities in Patients With Inflammatory Bowel Disease: A Survey Study During the COVID-19 Pandemic.

Background: Patients with inflammatory bowel disease (IBD) often experience worries related to travel due to frequent bowel movements. However, there is currently limited research focusing on the travel worries of patients with IBD. The aim of this study was to assess the level of worry regarding out-of-home activities in patients with IBD and identify factors associated with worry. Methods: This study included patients with IBD who visited the outpatient clinics between September 2020 and March 2022, during the COVID-19 pandemic. Participants completed a self-designed questionnaire, providing general clinical data and indicating their level of worry for out-of-home activities. Results: A total of 529 patients with IBD completed the questionnaire. Patients with Crohn's disease (CD) had a higher proportion of individuals under 40 years old and males compared to patients with ulcerative colitis (UC). Regarding out-of-home activities, patients with UC expressed greater worry about going out and taking buses than patients with CD. However, there were no significant differences observed between the two groups in terms of travel worries and worries about finding public washrooms. A significant majority (85.4%) of patients with clinically active IBD expressed worries about not finding public washrooms when going out, while 46.7% of patients in clinical remission had similar worries. Moreover, the worry about finding public washrooms was higher in patients with UC compared to those with CD, both during the clinical activity and remission. Conclusion: This survey conducted during the COVID-19 pandemic reported worries among patients with IBD about out-of-home activities. The patients with clinically active IBD, especially UC, expressed worries about not finding public washrooms when going out. We highlight the actual psychological and quality of life challenges faced by patients with IBD.

The role of hydrogen sulfide regulation of ferroptosis in different diseases.

Ferroptosis is a programmed cell death that relies on iron and lipid peroxidation. It differs from other forms of programmed cell death such as necrosis, apoptosis and autophagy. More and more evidence indicates that ferroptosis participates in many types of diseases, such as neurodegenerative diseases, ischemia-reperfusion injury, cardiovascular diseases and so on. Hence, clarifying the role and mechanism of ferroptosis in diseases is of great significance for further understanding the pathogenesis and treatment of some diseases. Hydrogen sulfide (H2S) is a colorless and flammable gas with the smell of rotten eggs. Many years ago, H2S was considered as a toxic gas. however, in recent years, increasing evidence indicates that it is the third important gas signaling molecule after nitric oxide and carbon monoxide. H2S has various physiological and pathological functions such as antioxidant stress, anti-inflammatory, anti-apoptotic and anti-tumor, and can participate in various diseases. It has been reported that H2S regulation of ferroptosis plays an important role in many types of diseases, however, the related mechanisms are not fully clear. In this review, we reviewed the recent literature about the role of H2S regulation of ferroptosis in diseases, and analyzed the relevant mechanisms, hoping to provide references for future in-depth researches.

Genome-wide identification of bZIP transcription factors and their expression analysis in Platycodon grandiflorus under abiotic stress.

The Basic Leucine Zipper (bZIP) transcription factors (TFs) family is among of the largest and most diverse gene families found in plant species, and members of the bZIP TFs family perform important functions in plant developmental processes and stress response. To date, bZIP genes in Platycodon grandiflorus have not been characterized. In this work, a number of 47 PgbZIP genes were identified from the genome of P. grandiflorus, divided into 11 subfamilies. The distribution of these PgbZIP genes on the chromosome and gene replication events were analyzed. The motif, gene structure, cis-elements, and collinearity relationships of the PgbZIP genes were simultaneously analyzed. In addition, gene expression pattern analysis identified ten candidate genes involved in the developmental process of different tissue parts of P. grandiflorus. Among them, Four genes (PgbZIP5, PgbZIP21, PgbZIP25 and PgbZIP28) responded to drought and salt stress, which may have potential biological roles in P. grandiflorus development under salt and drought stress. Four hub genes (PgbZIP13, PgbZIP30, PgbZIP32 and PgbZIP45) mined in correlation network analysis, suggesting that these PgbZIP genes may form a regulatory network with other transcription factors to participate in regulating the growth and development of P. grandiflorus. This study provides new insights regarding the understanding of the comprehensive characterization of the PgbZIP TFs for further exploration of the functions of growth and developmental regulation in P. grandiflorus and the mechanisms for coping with abiotic stress response.

Clinical validation of automated depth camera-based measurement of the Fugl-Meyer assessment for upper extremity.

OBJECTIVE: Depth camera-based measurement has demonstrated efficacy in automated assessment of upper limb Fugl-Meyer Assessment for paralysis rehabilitation. However, there is a lack of adequately sized studies to provide clinical support. Thus, we developed an automated system utilizing depth camera and machine learning, and assessed its feasibility and validity in a clinical setting. DESIGN: Validation and feasibility study of a measurement instrument based on single cross-sectional data. SETTING: Rehabilitation unit in a general hospital. PARTICIPANTS: Ninety-five patients with hemiparesis admitted for inpatient rehabilitation unit (2021-2023). MAIN MEASURES: Scores for each item, excluding those related to reflexes, were computed utilizing machine learning models trained on participant videos and readouts from force test devices, while the remaining reflex scores were derived through regression algorithms. Concurrent criterion validity was evaluated using sensitivity, specificity, percent agreement and Cohen's Kappa coefficient for ordinal scores of individual items, as well as correlations and intraclass correlation coefficients for total scores. Video-based manual assessment was also conducted and compared to the automated tools. RESULT: The majority of patients completed the assessment without therapist intervention. The automated scoring models demonstrated superior validity compared to video-based manual assessment across most items. The total scores derived from the automated assessment exhibited a high coefficient of 0.960. However, the validity of force test items utilizing force sensing resistors was relatively low. CONCLUSION: The integration of depth camera technology and machine learning models for automated Fugl-Meyer Assessment demonstrated acceptable validity and feasibility, suggesting its potential as a valuable tool in rehabilitation assessment.

Neutrophil-to-lymphocyte ratio in colorectal tissue affects prognosis in patients with colorectal cancer.

The objective of this investigation was to analyse the correlation between the neutrophil-to-lymphocyte ratio (NLR) status in the immune microenvironment (IME) and the prognostic outcomes of patients who have undergone radical surgery for colorectal cancer (CRC). In light of the continued prevalence of CRC in China, this study utilised Kaplan-Meier and Cox regression analyses to assess the prognostic relevance of NLR status in IME among patients with CRC. Furthermore, cellular experiments, such as cell scratching, were conducted to elucidate the underlying mechanisms of NLR's impact on CRC. The NLR status in IME has been found to have a significant impact on the prognosis of patients with CRC. Patients who exhibit elevated intratumoural and extratumoural NLR are associated with a poor prognosis. Experimental evidence indicates that tumour-associated neutrophil (TAN) augments the migratory, invasive, and proliferative potential of HT-29, HCT-116 and LOVO colorectal cancer cells, while concurrently reducing their sensitivity to oxaliplatin. Conversely, lymphocytes have demonstrated cytotoxic effects on HT-29 cells. The NLR status in IME may serve as a prognostic biomarker for resectable CRC.

Emerging insights into the role of NLRP3 inflammasome and endoplasmic reticulum stress in renal diseases.

NLRP3 inflammasome is a key component of the innate immune system, mediating the activation of caspase-1, and the maturity and secretion of the pro-inflammatory cytokine interleukin (IL)-1beta (IL-1ß) and IL-18 to cope with microbial infections and cell injury. The NLRP3 inflammasome is activated by various endogenous danger signals, microorganisms and environmental stimuli, including urate, extracellular adenosine triphosphate (ATP) and cholesterol crystals. Increasing evidence indicates that the abnormal activation of NLRP3 is involved in multiple diseases including renal diseases. Hence, clarifying the mechanism of action of NLRP3 inflammasome in different diseases can help prevent and treat various diseases. Endoplasmic reticulum (ER) is an important organelle which participates in cell homeostasis maintenance and protein quality control. The unfolded protein response (UPR) and ER stress are caused by the excessive accumulation of unfolded or misfolded proteins in ER to recover ER homeostasis. Many factors can cause ER stress, including inflammation, hypoxia, environmental toxins, viral infections, glucose deficiency, changes in Ca2+ level and oxidative stress. The dysfunction of ER stress participates in multiple diseases, such as renal diseases. Many previous studies have shown that NLRP3 inflammasome and ER stress play an important role in renal diseases. However, the relevant mechanisms are not yet fully clear. Herein, we focus on the current understanding of the role and mechanism of ER stress and NLRP3 inflammasome in renal diseases, hoping to provide theoretical references for future related researches.

LC3-associated phagocytosis of neutrophils triggers tumor ferroptotic cell death in glioblastoma.

Necrosis in solid tumors is commonly associated with poor prognostic but how these lesions expand remains unclear. Studies have found that neutrophils associate with and contribute to necrosis development in glioblastoma by inducing tumor cell ferroptosis through transferring myeloperoxidase-containing granules. However, the mechanism of neutrophilic granule transfer remains elusive. We performed an unbiased small molecule screen and found that statins inhibit neutrophil-induced tumor cell death by blocking the neutrophilic granule transfer. Further, we identified a novel process wherein neutrophils are engulfed by tumor cells before releasing myeloperoxidase-containing contents into tumor cells. This neutrophil engulfment is initiated by integrin-mediated adhesion, and further mediated by LC3-associated phagocytosis (LAP), which can be blocked by inhibiting the Vps34-UVRAG-RUBCN-containing PI3K complex. Myeloperoxidase inhibition or Vps34 depletion resulted in reduced necrosis formation and prolonged mouse survival in an orthotopic glioblastoma mouse model. Thus, our study unveils a critical role for LAP-mediated neutrophil internalization in facilitating the transfer of neutrophilic granules, which in turn triggers tumor cell death and necrosis expansion. Targeting this process holds promise for improving glioblastoma prognosis.

Efflux transporters in drug disposition during pregnancy.

Evidence-based dose selection of drugs in pregnant women has been lacking due to challenges in studying maternal-fetal pharmacokinetics. Hence, many drugs are administered off-label during pregnancy based on data obtained from non-pregnant women. During pregnancy, drug transporters play an important role in drug disposition along with known gestational age-dependent changes in physiology and drug-metabolizing enzymes. In this review, as Dr. Qingcheng Mao's former and current lab members, we summarize the collective contributions of Dr. Mao, who lost his life to cancer, focusing on the role of drug transporters in drug disposition during pregnancy. Dr. Mao and his team initiated their research by characterizing the structure of Breast Cancer Resistance Protein [BCRP, ATP-Binding Cassette (ABC) G2]. Subsequently, they have made significant contributions to the understanding of the role of BCRP and other transporters, particularly P-glycoprotein (P-gp/ABCB1), in the exposure of pregnant women and their fetuses to various drugs, including nitrofurantoin, glyburide, buprenorphine, bupropion, tetrahydrocannabinol, and their metabolites. This review also highlights the gestation- and pregnancy-dependent transporter expression at the blood-brain and blood-placenta barriers in mice. Significance Statement Dr. Qingcheng Mao and his team have made significant contributions to the investigation of the role of efflux transporters, especially P-glycoprotein and breast cancer resistance protein, in maternal-fetal exposure to many xenobiotics: nitrofurantoin, glyburide, buprenorphine, bupropion, tetrahydrocannabinol and their metabolites. Studies of individual compounds and the expression of transporters during gestation and pregnancy have improved the understanding of maternal-fetal pharmacokinetics.

Enhanced pyroptosis induction with pore-forming gene delivery for osteosarcoma microenvironment reshaping.

Osteosarcoma is the most common malignant bone tumor without efficient management for improving 5-year event-free survival. Immunotherapy is also limited due to its highly immunosuppressive tumor microenvironment (TME). Pore-forming gasdermins (GSDMs)-mediated pyroptosis has gained increasing concern in reshaping TME, however, the expressions and relationships of GSDMs with osteosarcoma remain unclear. Herein, gasdermin E (GSDME) expression is found to be positively correlated with the prognosis and immune infiltration of osteosarcoma patients, and low GSDME expression was observed. A vector termed as LPAD contains abundant hydroxyl groups for hydrating layer formation was then prepared to deliver the GSDME gene to upregulate protein expression in osteosarcoma for efficient TME reshaping via enhanced pyroptosis induction. Atomistic molecular dynamics simulations analysis proved that the hydroxyl groups increased LPAD hydration abilities by enhancing coulombic interaction. The upregulated GSDME expression together with cleaved caspase-3 provided impressive pyroptosis induction. The pyroptosis further initiated proinflammatory cytokines release, increased immune cell infiltration, activated adaptive immune responses and create a favorable immunogenic hot TME. The study not only confirms the role of GSDME in the immune infiltration and prognosis of osteosarcoma, but also provides a promising strategy for the inhibition of osteosarcoma by pore-forming GSDME gene delivery induced enhanced pyroptosis to reshape the TME of osteosarcoma.

Impact of Preoperative Neutrophil to Prealbumin Ratio Index (NPRI) on Short-Term Complications and Long-Term Prognosis in Patients Undergoing Laparoscopic Radical Surgery for Colorectal Cancer.

Objective: This study aims to evaluate the impact and predictive value of the preoperative NPRI on short-term complications and long-term prognosis in patients undergoing laparoscopic radical surgery for colorectal cCancer (CRC). Methods: A total of 302 eligible CRC patients were included, assessing five inflammation-and nutrition-related markers and various clinical features for their predictive impact on postoperative outcomes. Emphasis was on the novel indicator NPRI to elucidate its prognostic and predictive value for perioperative risks. Results: Multivariate logistic regression analysis identified a history of abdominal surgery, prolonged surgical duration, CEA levels ≥5 ng/mL, and NPRI ≥ 3.94 × 10-2 as independent risk factors for postoperative complications in CRC patients. The Clavien--Dindo complication grading system highlighted the close association between preoperative NPRI and both common and severe complications. Multivariate analysis also identified a history of abdominal surgery, tumor diameter ≥5 cm, poorly differentiated or undifferentiated tumors, and NPRI ≥ 2.87 × 10-2 as independent risk factors for shortened overall survival (OS). Additionally, a history of abdominal surgery, tumor maximum diameter ≥5 cm, tumor differentiation as poor/undifferentiated, NPRI ≥ 2.87 × 10-2, and TNM Stage III were determined as independent risk factors for shortened disease-free survival (DFS). Survival curve results showed significantly higher 5-year OS and DFS in the low NPRI group compared to the high NPRI group. The incorporation of NPRI into nomograms for OS and DFS, validated through calibration and decision curve analyses, attested to the excellent accuracy and practicality of these models. Conclusion: Preoperative NPRI independently predicts short-term complications and long-term prognosis in patients undergoing laparoscopic colorectal cancer surgery, enhancing predictive accuracy when incorporated into nomograms for patient survival.

Federated Fuzzy Clustering for Decentralized Incomplete Longitudinal Behavioral Data.

The use of medical data for machine learning, including unsupervised methods such as clustering, is often restricted by privacy regulations such as the Health Insurance Portability and Accountability Act (HIPAA). Medical data is sensitive and highly regulated and anonymization is often insufficient to protect a patient's identity. Traditional clustering algorithms are also unsuitable for longitudinal behavioral health trials, which often have missing data and observe individual behaviors over varying time periods. In this work, we develop a new decentralized federated multiple imputation-based fuzzy clustering algorithm for complex longitudinal behavioral trial data collected from multisite randomized controlled trials over different time periods. Federated learning (FL) preserves privacy by aggregating model parameters instead of data. Unlike previous FL methods, this proposed algorithm requires only two rounds of communication and handles clients with varying numbers of time points for incomplete longitudinal data. The model is evaluated on both empirical longitudinal dietary health data and simulated clusters with different numbers of clients, effect sizes, correlations, and sample sizes. The proposed algorithm converges rapidly and achieves desirable performance on multiple clustering metrics. This new method allows for targeted treatments for various patient groups while preserving their data privacy and enables the potential for broader applications in the Internet of Medical Things.

QTL mapping for the flag leaf-related traits using RILs derived from Trititrigia germplasm line SN304 and wheat cultivar Yannong15 in multiple environments.

BACKGROUND: Developing and enriching genetic resources plays important role in the crop improvement. The flag leaf affects plant architecture and contributes to the grain yield of wheat (Triticum aestivum L.). The genetic improvement of flag leaf traits faces problems such as a limited genetic basis. Among the various genetic resources of wheat, Thinopyrum intermedium has been utilized as a valuable resource in genetic improvement due to its disease resistance, large spikes, large leaves, and multiple flowers. In this study, a recombinant inbred line (RIL) population was derived from common wheat Yannong15 and wheat-Th. intermedium introgression line SN304 was used to identify the quantitative trait loci (QTL) for flag leaf-related traits. RESULTS: QTL mapping was performed for flag leaf length (FLL), flag leaf width (FLW) and flag leaf area (FLA). A total of 77 QTLs were detected, and among these, 51 QTLs with positive alleles were contributed by SN304. Fourteen major QTLs for flag leaf traits were detected on chromosomes 2B, 3B, 4B, and 2D. Additionally, 28 QTLs and 8 QTLs for flag leaf-related traits were detected in low-phosphorus and drought environments, respectively. Based on major QTLs of positive alleles from SN304, we identified a pair of double-ended anchor primers mapped on chromosome 2B and amplified a specific band of Th. intermedium in SN304. Moreover, there was a major colocated QTL on chromosome 2B, called QFll/Flw/Fla-2B, which was delimited to a physical interval of approximately 2.9 Mb and contained 20 candidate genes. Through gene sequence and expression analysis, four candidate genes associated with flag leaf formation and growth in the QTL interval were identified. CONCLUSION: These results promote the fine mapping of QFll/Flw/Fla-2B, which have pleiotropic effects, and will facilitate the identification of candidate genes for flag leaf-related traits. Additionally, this work provides a theoretical basis for the application of Th. intermedium in wheat breeding.

In Situ Imaging of Two-Dimensional Crystal Growth Using a Heat-Resistant Optical Microscope.

Revealing low-dimensional material growth dynamics is critical for crystal growth engineering. However, in a practical high-temperature growth system, the crystal growth process is a black box because of the lack of heat-resistant imaging tools. Here, we develop a heat-resistant optical microscope and embed it in a chemical vapor deposition (CVD) system to investigate two-dimensional (2D) crystal growth dynamics. This in situ optical imaging CVD system can tolerate temperatures of ≤900 °C with a spatial resolution of ∼1 µm. The growth of monolayer MoS2 crystals was studied as a model for 2D crystal growth. The nucleation and growth process have been imaged. Model analysis and simulation have revealed the growth rate, diffusion coefficient, and spatial distribution of the precursor. More importantly, a new vertex-kink-ledge model has been suggested for monolayer crystal growth. This work provides a new technique for in situ microscopic imaging at high temperatures and fundamental insight into 2D crystal growth.

Interneuron FGF13 regulates seizure susceptibility via a sodium channel-independent mechanism.

Developmental and Epileptic Encephalopathies (DEEs), a class of devastating neurological disorders characterized by recurrent seizures and exacerbated by disruptions to excitatory/inhibitory balance in the brain, are commonly caused by mutations in ion channels. Disruption of, or variants in, FGF13 were implicated as causal for a set of DEEs, but the underlying mechanisms were clouded because FGF13 is expressed in both excitatory and inhibitory neurons, FGF13 undergoes extensive alternative splicing producing multiple isoforms with distinct functions, and the overall roles of FGF13 in neurons are incompletely cataloged. To overcome these challenges, we generated a set of novel cell type-specific conditional knockout mice. Interneuron-targeted deletion of Fgf13 led to perinatal mortality associated with extensive seizures and impaired the hippocampal inhibitory/excitatory balance while excitatory neuron-targeted deletion of Fgf13 caused no detectable seizures and no survival deficits. While best studied as a voltage-gated sodium channel (Nav) regulator, we observed no effect of Fgf13 ablation in interneurons on Navs but rather a marked reduction in K+ channel currents. Re-expressing different Fgf13 splice isoforms could partially rescue deficits in interneuron excitability and restore K+ channel current amplitude. These results enhance our understanding of the molecular mechanisms that drive the pathogenesis of Fgf13-related seizures and expand our understanding of FGF13 functions in different neuron subsets.

Advances in fecal microbiota transplantation for the treatment of diabetes mellitus.

Diabetes mellitus (DM) refers to a group of chronic diseases with global prevalence, characterized by persistent hyperglycemia resulting from various etiologies. DM can harm various organ systems and lead to acute or chronic complications, which severely endanger human well-being. Traditional treatment mainly involves controlling blood sugar levels through replacement therapy with drugs and insulin; however, some patients still find a satisfactory curative effect difficult to achieve. Extensive research has demonstrated a close correlation between enteric dysbacteriosis and the pathogenesis of various types of DM, paving the way for novel therapeutic approaches targeting the gut microbiota to manage DM. Fecal microbiota transplantation (FMT), a method for re-establishing the intestinal microbiome balance, offers new possibilities for treating diabetes. This article provides a comprehensive review of the correlation between DM and the gut microbiota, as well as the current advancements in FMT treatment for DM, using FMT as an illustrative example. This study aims to offer novel perspectives and establish a theoretical foundation for the clinical diagnosis and management of DM.

Role of Helicobacter pylori virulence factors and alteration of the Tumor Immune Microenvironment: challenges and opportunities for Cancer Immunotherapy.

Various forms of malignancies have been linked to Helicobacter pylori. Despite advancements in chemotherapeutic and surgical approaches, the management of cancer, particularly at advanced stages, increasingly relies on the integration of immunotherapy. As a novel, safe therapeutic modality, immunotherapy harnesses the immune system of the patient to treat cancer, thereby broadening treatment options. However, there is evidence that H. pylori infection may influence the effectiveness of immunotherapy in various types of cancer. This association is related to H. pylori virulence factors and the tumor microenvironment. This review discusses the influence of H. pylori infection on immunotherapy in non-gastrointestinal and gastrointestinal tumors, the mechanisms underlying this relationship, and directions for the development of improved immunotherapy strategies.

Identification of membrane curvature sensing motifs essential for VPS37A phagophore recruitment and autophagosome closure.

VPS37A, an ESCRT-I complex component, is required for recruiting a subset of ESCRT proteins to the phagophore for autophagosome closure. However, the mechanism by which VPS37A is targeted to the phagophore remains obscure. Here, we demonstrate that the VPS37A N-terminal domain exhibits selective interactions with highly curved membranes, mediated by two membrane-interacting motifs within the disordered regions surrounding its Ubiquitin E2 variant-like (UEVL) domain. Site-directed mutations of residues in these motifs disrupt ESCRT-I localization to the phagophore and result in defective phagophore closure and compromised autophagic flux in vivo, highlighting their essential role during autophagy. In conjunction with the UEVL domain, we postulate that these motifs guide a functional assembly of the ESCRT machinery at the highly curved tip of the phagophore for autophagosome closure. These results advance the notion that the distinctive membrane architecture of the cup-shaped phagophore spatially regulates autophagosome biogenesis.