Membrane Recycling Research Articles

Endo-IP and Lyso-IP Toolkit for Endolysosomal Profiling of Human Induced Neurons.

Plasma membrane protein degradation and recycling is regulated by the endolysosomal system, wherein endosomes bud from the plasma membrane into the cytosol and mature into degradative lysosomes. As such, the endolysosomal system plays a critical role in determining the abundance of proteins on the cell surface, influencing cellular identity and function. Highly polarized cells, like neurons, rely on the endolysosomal system for axonal and dendritic specialization and synaptic compartmentalization. The importance of this system to neuronal function is reflected by the prevalence of risk variants in components of the system in several neurodegenerative diseases, ranging from Parkinson's to Alzheimer's disease. Nevertheless, our understanding of endocytic cargo and core endolysosomal machinery in neurons is limited, in part due to technical limitations. Here, we developed a toolkit for capturing EEA1-postive endosomes (Endo-IP) and TMEM192-positive lysosomes (Lyso-IP) in stem cell-derived induced neurons (iNeurons). We demonstrated its utility by revealing the endolysosomal protein landscapes for cortical-like iNeurons and stem cells. This allowed us to globally profile endocytic cargo, identifying hundreds of transmembrane proteins, including neurogenesis and synaptic proteins, as well as endocytic cargo with predicted SNX17 or SNX27 recognition motifs. By contrast, parallel lysosome profiling reveals a simpler protein repertoire, reflecting in part temporally controlled recycling or degradation for many endocytic targets. This system will facilitate mechanistic interrogation of endolysosomal components found as risk factors in neurodegenerative disease.

Abstract IA-08: Syndecan 1 is a therapeutic target for KRAS-driven pancreatic cancer

Abstract KRAS inhibitors targeting G12C mutation have been approved by FDA for the treatment of non-small cell lung cancers and have shown promising clinical responses in pancreatic ductal adenocarcinoma (PDAC). RAS inhibitors targeting additional KRAS mutations or multiple RAS isoforms are under clinical development. Although targeting KRAS exhibits anti-tumor effect in PDAC, majority of tumors inevitably develop resistant disease, as is the case for most targeted therapies. In this new era of targeting KRAS driven cancer, understanding mechanisms driving this resistance to RAS targeted therapies and further devising combination strategies to overcome it have become a necessary, though challenging, task to achieve long term disease control. To tackle this problem, we employed various in vitro and in vivo preclinical model systems to explore the development of resistance to both genetic and pharmacological KRAS blockade. Our previous work identified the membrane proteoglycan Syndecan 1 (SDC1) as a KRAS downstream surrogate whose cell surface localization is tightly controlled by oncogenic KRAS signaling and is critical for KRAS-driven tumor development. Here, our analysis of KRAS driven genetically engineered PDAC mouse model and human pancreatic or colorectal cancer (CRC) cells with KRASG12C mutation discovered that, while cell surface SDC1 is reduced upon acute genetic or pharmacological inhibition of oncogenic KRAS, plasma membrane SDC1 is recovered in tumor cells that become resistant to KRAS inhibition (KRAS-bypass cells). Surface localization of SDC1 leads to the activation of multiple receptor tyrosine kinases (RTKs) and macropinocytosis, resulting in the resistance to KRAS blockade. We further identified that the recovery of plasma membrane SDC1 in KRAS-bypass cells is driven by YAP1 oncogene, which induces the downregulation of ARF6 GAPs, leading to the activation of ARF6, a small GTPase required for SDC1 membrane recycling. To therapeutically targeting SDC1, we have successfully developed a monoclonal antibody (22B mAb), which exhibits remarkable sensitivity and specificity for human SDC1. Our results indicate that 22B mAb exerts substantial inhibition of PDAC cell growth in vitro and desirable tumor inhibitory effects in vivo in murine PDAC tumors and human PDAC cell-derived xenograft tumors. Importantly, our 22B mAb synergizes with KRAS inhibitors, chemotherapy, or immunotherapy, resulting in significantly enhanced therapeutic effects. Taken together, our study identified SDC1 as a functional driver for the bypass of KRAS-dependence and therapeutically targeting SDC1 with a novel mAb will overcome the acquired resistance to KRAS targeted therapy. As such, our research yields important new insights in the fields of cancer biology regarding mechanisms of resistance employed by human cancers, and identifies new actionable therapeutic targets and approaches to overcome resistance to KRAS inhibition. Citation Format: Mitsunobu Takeda, Zecheng Yang, Madeline S Theardy, Alexey Sorokin, Oluwadara Coker, Shuaitong Chen, Long T Vien, Laura Bover, Haoqiang Ying, Scott Kopetz, Wantong Yao. Syndecan 1 is a therapeutic target for KRAS-driven pancreatic cancer [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Advances in Pancreatic Cancer Research; 2024 Sep 15-18; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2024;84(17 Suppl_2):Abstract nr IA-08.

Recycling and 3D-Printing Biodegradable Membranes for Gas Separation-toward a Membrane Circular Economy.

Polymer membranes employed in gas separation play a pivotal role in advancing environmental sustainability, energy production, and gas purification technologies. Despite their significance, the current design and manufacturing of these membranes lack cradle-to-cradle approaches, contributing to plastic waste pollution. This study explores emerging solutions, including the use of biodegradable biopolymers such as polyhydroxybutyrate (PHB) and membrane recycling, with a focus on the specific impact of mechanical recycling on the performance of biodegradable gas separation membranes. This research represents the first systematic exploration of recycling biodegradable membranes for gas separation. Demonstrating that PHB membranes can be recycled and remanufactured without solvents using hot-melt extrusion and 3D printing, the research highlights PHB's promising performance in developing more sustainable CO2 separations, despite an increase in gas permeability with successive recycling steps due to reduced polymer molecular weight. The study emphasizes the excellent thermal, chemical, and mechanical stability of PHB membranes, albeit with a marginal reduction in gas selectivity upon recycling. However, limitations in PHB's molecular weight affecting extrudability and processability restrict the recycling to three cycles. Anticipating that this study will serve as a foundational exploration, we foresee more sophisticated recycling studies for gas separation membranes, paving the way for a circular economy in future membrane technologies.

Do Arabinogalactan Proteins Occur in the Transfer Cells of Utricularia dichotoma?

Species in the genus Utricularia are carnivorous plants that prey on invertebrates using traps of leaf origin. The traps are equipped with numerous different glandular trichomes. Trichomes (quadrifids) produce digestive enzymes and absorb the products of prey digestion. The main aim of this study was to determine whether arabinogalactan proteins (AGPs) occur in the cell wall ingrowths in the quadrifid cells. Antibodies (JIM8, JIM13, JIM14, MAC207, and JIM4) that act against various groups of AGPs were used. AGP localization was determined using immunohistochemistry techniques and immunogold labeling. AGPs localized with the JIM13, JIM8, and JIM14 epitopes occurred in wall ingrowths of the pedestal cell, which may be related to the fact that AGPs regulate the formation of wall ingrowths but also, due to the patterning of the cell wall structure, affect symplastic transport. The presence of AGPs in the cell wall of terminal cells may be related to the presence of wall ingrowths, but processes also involve vesicle trafficking and membrane recycling, in which these proteins participate.

Sustainable membrane technology for water purification—Manufacturing, recycling and environmental impacts

Water pollution has become a serious threat to our ecosystem. Water contamination due to human, commercial, and industrial activities has negatively affected the whole world. Owing to the global demanding challenges of water pollution treatments and achieving sustainability, membrane technology has gained increasing research attention. Although numerous membrane materials have focused, the sustainable water purification membranes are most effective for environmental needs. In this regard sustainable, green, and recyclable polymeric and nanocomposite membranes have been developed. Materials fulfilling sustainable environmental demands usually include wide-ranging polyesters, polyamides, polysulfones, and recyclable/biodegradable petroleum polymers plus non-toxic solvents. Consequently, water purification membranes for nanofiltration, microfiltration, reverse osmosis, ultrafiltration, and related filtration processes have been designed. Sustainable polymer membranes for water purification have been manufactured using facile techniques. The resulting membranes have been tested for desalination, dye removal, ion separation, and antibacterial processes for wastewater. Environmental sustainability studies have also pointed towards desired life cycle assessment results for these water purification membranes. Recycling of water treatment membranes have been performed by three major processes mechanical recycling, chemical recycling, or thermal recycling. Moreover, use of sustainable membranes has caused positive environmental impacts for safe waste water treatment. Importantly, worth of sustainable water purification membranes has been analyzed for the environmentally friendly water purification applications. There is vast scope of developing and investigating water purification membranes using countless sustainable polymers, materials, and nanomaterials. Hence, value of sustainable membranes has been analyzed to meet the global demands and challenges to attain future clean water and ecosystem.

Protein networking: nicotinic acetylcholine receptors and their protein-protein-associations.

Nicotinic acetylcholine receptors (nAChR) are complex transmembrane proteins involved in neurotransmission in the nervous system and at the neuromuscular junction. nAChR disorders may lead to severe, potentially fatal pathophysiological states. To date, the receptor has been the focus of basic and applied research to provide novel therapeutic interventions. Since most studies have investigated only the nAChR itself, it is necessary to consider the receptor as part of its protein network to understand or elucidate-specific pathways. On its way through the secretory pathway, the receptor interacts with several chaperones and proteins. This review takes a closer look at these molecular interactions and focuses especially on endoplasmic reticulum biogenesis, secretory pathway sorting, Golgi maturation, plasma membrane presentation, retrograde internalization, and recycling. Additional knowledge regarding the nAChR protein network may lead to a more detailed comprehension of the fundamental pathomechanisms of diseases or may lead to the discovery of novel therapeutic drug targets.

New strategy for structure rearrangement of thin-film composite (TFC) polyamide (PA) membranes and offering potential use in both aqueous and organic solvents

The purity of sodium hexafluorophosphate (NaPF6) is crucial for the preparation of electrolytes in manufacturing. We propose a simple process in order to induce membrane structure rearrangement process (SRP) by activating thin-film composite (TFC) membranes with polyamide (PA) structure and explore their potential green recycling application in concentrating sodium-ion batteries (SIBs) electrolyte. The method utilizes a solution containing polar aprotic solvent as the soaking and activating solution to swell and disintegrate the loosely cross-linked PA layer, and a non-solvent solidification solution complete the SRP, enhancing the permeability of the PA layer while maintaining high rejection rates for divalent ions. Subsequently, during the further treatment of the membrane surface in structure rearrangement, tert-butanol (TBA) is introduced into the aqueous solution to reconstruct the surface PA layer, further improving the permeability. The optimal D8010T10 achieved a permeation flux of 24.2 L m−2 h−1·bar−1, with rejection rates for sodium sulfate (Na2SO4), magnesium chloride (MgCl2), and magnesium sulfate (MgSO4) reaching 94.7 %, 98.4 %, and 99.1 % respectively. And the mechanism of SRP with different solvent is analyzed and explained through dissipative particle dynamics (DPD) simulations. This study provides a commercially viable approach for manufacturing high-performance membranes. The D8010T10 membrane achieves more than 90 % separation efficiency for sodium hexafluorophosphate (NaPF6) dissolved in different solvents, providing a potential solution for the concentration and recovery of NaPF6 in lab-scale, verified its potential use in the organic solvent nanofiltration (OSN) and a path way for waste membrane recycling and degrading use in the industry.

Quantitative Measurement of Plasma Membrane Protein Internalisation and Recycling in Heterogenous Cellular Samples by Flow Cytometry.

Plasma membrane proteins mediate important aspects of physiology, including nutrient acquisition, cell-cell interactions, and monitoring homeostasis. The trafficking of these proteins, involving internalisation from and/or recycling back to the cell surface, is often critical to their functions. These processes can vary among different proteins and cell types and states and are still being elucidated. Current strategies to measure surface protein internalisation and recycling are typically microscopy or biochemical assays; these are accurate but generally limited to analysing a homogenous cell population and are often low throughput. Here, we present flow cytometry-based methods involving probe-conjugated antibodies that enable quantification of internalisation or recycling rates at the single-cell level in complex samples. To measure internalisation, we detail an assay where the protein of interest is labelled with a specific antibody conjugated to a fluorescent oligonucleotide-labelled probe. To measure recycling, a specific antibody conjugated to a cleavable biotin group is employed. These probes permit the differentiation of molecules that have been internalised or recycled from those that have not. When combined with cell-specific marker panels, these methods allow the quantitative study of plasma membrane protein trafficking dynamics in a heterogenous cell mixture at the single-cell level. Key features • These assays allow sensitive quantification of internalised or recycled surface molecules using oligonucleotide or cleavable biotin-conjugated probes, respectively, and detected by flow cytometry. • They can be adapted to any membrane protein that transits via the cell surface and for which a specific purified antibody is available. • The dynamics of a cell surface protein can be measured in heterogenous cell populations simultaneously, including various cellular activation states. • The internalisation assay builds upon the method developed by Liu et al. [1,2] and extends its application to heterogenous human peripheral blood mononuclear cells. • These assays have been extensively used on suspension cells but have not been tested on adherent cells.

Exploring the potential of decade-air exposed perovskite membranes through sustainable recycling approaches

The stability of perovskite-based oxygen permeable membranes under long-term storage conditions, especially in the presence of water and carbon dioxide, presents a significant challenge. In this study, we examined the impact of extended storage (more than 10 years) on Nb2O5-doped SrCo0.8Fe0.2O3-δ (10Yr-SCFN) membranes. To unlock their industrial application potential, various approaches involving a combination of physical and chemical treatments to restore membrane properties in aged membranes are proposed and validated, while systematically investigating the evolution in chemical composition, microstructure, mechanical strength, and oxygen permeability. The 10Yr-SCFN membranes can be effectively restored through the secondary sintering method, wherein the membrane is first powdered and then calcinated in static air to maximize the removal of impurities. The mechanical strength and oxygen permeability reach levels of 30 MPa and 1.2 ml cm−2 min−1 (900 °C), respectively, comparable to the performance of freshly prepared membranes. These findings shed some light on the potentiality of sustainable recycling of perovskite membranes and provide theoretical and technical support for the practical application and industrialization of oxygen permeable membranes.

Continuous endosomes form functional subdomains and orchestrate rapid membrane trafficking in trypanosomes

Endocytosis is a common process observed in most eukaryotic cells, although its complexity varies among different organisms. In Trypanosoma brucei, the endocytic machinery is under special selective pressure because rapid membrane recycling is essential for immune evasion. This unicellular parasite effectively removes host antibodies from its cell surface through hydrodynamic drag and fast endocytic internalization. The entire process of membrane recycling occurs exclusively through the flagellar pocket, an extracellular organelle situated at the posterior pole of the spindle-shaped cell. The high-speed dynamics of membrane flux in trypanosomes do not seem compatible with the conventional concept of distinct compartments for early endosomes (EE), late endosomes (LE), and recycling endosomes (RE). To investigate the underlying structural basis for the remarkably fast membrane traffic in trypanosomes, we employed advanced techniques in light and electron microscopy to examine the three-dimensional architecture of the endosomal system. Our findings reveal that the endosomal system in trypanosomes exhibits a remarkably intricate structure. Instead of being compartmentalized, it constitutes a continuous membrane system, with specific functions of the endosome segregated into membrane subdomains enriched with classical markers for EE, LE, and RE. These membrane subdomains can partly overlap or are interspersed with areas that are negative for endosomal markers. This continuous endosome allows fast membrane flux by facilitated diffusion that is not slowed by multiple fission and fusion events.

Continuous endosomes form functional subdomains and orchestrate rapid membrane trafficking in trypanosomes.

Endocytosis is a common process observed in most eukaryotic cells, although its complexity varies among different organisms. In Trypanosoma brucei, the endocytic machinery is under special selective pressure because rapid membrane recycling is essential for immune evasion. This unicellular parasite effectively removes host antibodies from its cell surface through hydrodynamic drag and fast endocytic internalization. The entire process of membrane recycling occurs exclusively through the flagellar pocket, an extracellular organelle situated at the posterior pole of the spindle-shaped cell. The high-speed dynamics of membrane flux in trypanosomes do not seem compatible with the conventional concept of distinct compartments for early endosomes (EE), late endosomes (LE), and recycling endosomes (RE). To investigate the underlying structural basis for the remarkably fast membrane traffic in trypanosomes, we employed advanced techniques in light and electron microscopy to examine the three-dimensional architecture of the endosomal system. Our findings reveal that the endosomal system in trypanosomes exhibits a remarkably intricate structure. Instead of being compartmentalized, it constitutes a continuous membrane system, with specific functions of the endosome segregated into membrane subdomains enriched with classical markers for EE, LE, and RE. These membrane subdomains can partly overlap or are interspersed with areas that are negative for endosomal markers. This continuous endosome allows fast membrane flux by facilitated diffusion that is not slowed by multiple fission and fusion events.

The proteasome modulates endocytosis specifically in glomerular cells to promote kidney filtration

Kidney filtration is ensured by the interaction of podocytes, endothelial and mesangial cells. Immunoglobulin accumulation at the filtration barrier is pathognomonic for glomerular injury. The mechanisms that regulate filter permeability are unknown. Here, we identify a pivotal role for the proteasome in a specific cell type. Combining genetic and inhibitor-based human, pig, mouse, and Drosophila models we demonstrate that the proteasome maintains filtration barrier integrity, with podocytes requiring the constitutive and glomerular endothelial cells the immunoproteasomal activity. Endothelial immunoproteasome deficiency as well as proteasome inhibition disrupt the filtration barrier in mice, resulting in pathologic immunoglobulin deposition. Mechanistically, we observe reduced endocytic activity, which leads to altered membrane recycling and endocytic receptor turnover. This work expands the concept of the (immuno)proteasome as a control protease orchestrating protein degradation and antigen presentation and endocytosis, providing new therapeutic targets to treat disease-associated glomerular protein accumulations.

Sustainability in Membrane Technology: Membrane Recycling and Fabrication Using Recycled Waste.

Membrane technology has shown a promising role in combating water scarcity, a globally faced challenge. However, the disposal of end-of-life membrane modules is problematic as the current practices include incineration and landfills as their final fate. In addition, the increase in population and lifestyle advancement have significantly enhanced waste generation, thus overwhelming landfills and exacerbating environmental repercussions and resource scarcity. These practices are neither economically nor environmentally sustainable. Recycling membranes and utilizing recycled material for their manufacturing is seen as a potential approach to address the aforementioned challenges. Depending on physiochemical conditions, the end-of-life membrane could be reutilized for similar, upgraded, and downgraded operations, thus extending the membrane lifespan while mitigating the environmental impact that occurred due to their disposal and new membrane preparation for similar purposes. Likewise, using recycled waste such as polystyrene, polyethylene terephthalate, polyvinyl chloride, tire rubber, keratin, and cellulose and their derivates for fabricating the membranes can significantly enhance environmental sustainability. This study advocates for and supports the integration of sustainability concepts into membrane technology by presenting the research carried out in this area and rigorously assessing the achieved progress. The membranes' recycling and their fabrication utilizing recycled waste materials are of special interest in this work. Furthermore, this study offers guidance for future research endeavors aimed at promoting environmental sustainability.

Disorders of vesicular trafficking presenting with recurrent acute liver failure: NBAS, RINT1, and SCYL1 deficiency.

Among genetic disorders of vesicular trafficking, there are three causing recurrent acute liver failure (RALF): NBAS, RINT1, and SCYL1-associated disease. These three disorders are characterized by liver crises triggered by febrile infections and account for a relevant proportion of RALF causes. While the frequency and severity of liver crises in NBAS and RINT1-associated disease decrease with age, patients with SCYL1 variants present with a progressive, cholestatic course. In all three diseases, there is a multisystemic, partially overlapping phenotype with variable expression, including liver, skeletal, and nervous systems, all organ systems with high secretory activity. There are no specific biomarkers for these diseases, and whole exome sequencing should be performed in patients with RALF of unknown etiology. NBAS, SCYL1, and RINT1 are involved in antegrade and retrograde vesicular trafficking. Pathomechanisms remain unclarified, but there is evidence of a decrease in concentration and stability of the protein primarily affected by the respective gene defect and its interaction partners, potentially causing impairment of vesicular transport. The impairment of protein secretion by compromised antegrade transport provides a possible explanation for different organ manifestations such as bone alteration due to lack of collagens or diabetes mellitus when insulin secretion is affected. Dysfunction of retrograde transport impairs membrane recycling and autophagy. The impairment of vesicular trafficking results in increased endoplasmic reticulum stress, which, in hepatocytes, can progress to hepatocytolysis. While there is no curative therapy, an early and consequent implementation of an emergency protocol seems crucial for optimal therapeutic management.

Leucine Zipper Downregulated in Cancer-1 Interacts with Clathrin Adaptors to Control Epidermal Growth Factor Receptor (EGFR) Internalization and Gefitinib Response in EGFR-Mutated Non-Small Cell Lung Cancer.

The epidermal growth factor receptor (EGFR) is a common driver of non-small cell lung cancer (NSCLC). Clathrin-mediated internalization (CMI) sustains EGFR signaling. AXL is associated with resistance to EGFR-tyrosine kinase inhibitors (TKIs) in EGFR-mutated (EGFRM) NSCLC. We investigated the effects of Leucine zipper downregulated in cancer-1 (LDOC1) on EGFR CMI and NSCLC treatment. Coimmunoprecipitation, double immunofluorescence staining, confocal microscopy analysis, cell surface labelling assays, and immunohistochemistry studies were conducted. We revealed that LDOC1 interacts with clathrin adaptors through binding motifs. LDOC1 depletion promotes internalization and plasma membrane recycling of EGFR in EGFRM NSCLC PC9 and HCC827 cells. Membranous and cytoplasmic EGFR decreased and increased, respectively, in LDOC1 (-) NSCLC tumors. LDOC1 depletion enhanced and sustained activation of EGFR, AXL, and HER2 and enhanced activation of HER3 in PC9 and HCC827 cells. Sensitivity to first-generation EGFR-TKIs (gefitinib and erlotinib) was significantly reduced in LDOC1-depleted PC9 and HCC827 cells. Moreover, LDOC1 downregulation was significantly associated (p < 0.001) with poor overall survival in patients with EGFRM NSCLC receiving gefitinib (n = 100). In conclusion, LDOC1 may regulate the efficacy of first-generation EGFR-TKIs by participating in the CMI of EGFR. Accordingly, LDOC1 may function as a prognostic biomarker for EGFRM NSCLC.

Abstract C096: Targeting Syndecan1 to overcome acquired resistant to KRAS inhibitor in gastrointestinal cancer

Abstract Development of treatment resistance is a major impediment to effective cancer therapy. KRASG12C inhibitors have been recently approved by FDA and specific inhibitors targeting additional KRAS mutations are under clinical and preclinical development. These KRAS oncogene-specific inhibitors (KRASi) represent a promising new targeted therapy for KRAS-driven cancer types. However, as is the case for most targeted therapies, majority of tumors that initially respond to KRASG12C inhibitor quickly develop resistant disease. Unfortunately, the underlying mechanisms of KRASi resistance remain to be fully elucidated. We employed various in vitro and in vivo preclinical model systems to explore the development of KRASi resistance. Our study demonstrated that the YAP1- Syndecan 1 (SDC1) axis as the major driver for the bypass of KRAS-dependence and targeting YAP1-SDC1 will overcome the acquired resistance to KRAS targeted therapy. We previously identified the membrane proteoglycan SDC1 as a KRAS downstream surrogate whose cell surface localization is tightly controlled by oncogenic KRAS signaling and is critical for KRAS-driven tumor development. Here, our analysis of KRAS driven genetically engineered mouse model of pancreatic ductal adenocarcinoma (PDAC) and human pancreatic or colorectal cancer (CRC) cells with KRASG12C mutation discovered that, while cell surface SDC1 is reduced upon acute genetic or pharmacological of oncogenic KRAS, plasma membrane SDC1 is recovered in tumor cells that become resistant to KRAS inhibition (KRAS-bypass cells). Surface localization of SDC1 leads to the activation of multiple receptor tyrosine kinases (RTKs), resulting in the resistance to KRAS blockade. We further identified that the recovery of plasma membrane SDC1 in KRAS-bypass cells is driven by YAP1 oncogene, which mediates the transcription suppression of ARF6 GAPs, leading to the activation of ARF6, a small GTPase required for SDC1 membrane recycling. Genetic depletion of YAP1 or SDC1, as well as pharmacological inhibition of YAP1-SDC1 axis abolishes the tumorigenic activity of KRAS-bypass tumor cells and sensitizes KRAS-driven tumors to KRASi. Moreover, YAP1 and surface SDC1 are accumulated in CRC PDX models with acquired resistance to KRASG12C-inhibitor. Importantly, pharmacological targeting YAP1 significantly suppresses surface SDC1 in KRASi-resistant PDXs and sensitizes the tumors to KRASG12C-inhibitor. Taken together, our research identifies new actionable therapeutic targets and approaches to overcome resistance to KRAS inhibition, thus implicating the therapeutic potential to greatly improve the clinical outcome of patients with KRAS mutated cancers. Citation Format: Mitsunobu Takeda, Alexey Sorokin, Madelaine Theardy, Oluwadara Coker, Scott Kopetz, Haoqiang Ying, Giulio Draetta, Ronald A. DePinho, Wantong Yao. Targeting Syndecan1 to overcome acquired resistant to KRAS inhibitor in gastrointestinal cancer [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Pancreatic Cancer; 2023 Sep 27-30; Boston, Massachusetts. Philadelphia (PA): AACR; Cancer Res 2024;84(2 Suppl):Abstract nr C096.

New progress in the deep understanding of the biocake layer property: Combined effect of neglected protein secondary structure, morphology, and mechanism

The application of magnetic fields (MFs) and magnetic particles (MPs) in water treatment has attracted widespread attention due to their stability, strong biological compatibility, and less chemical consumption. This study introduced MPs and MFs to GDM and probed their effects on filtration performance. Predeposited large MPs (P-large) and batch-added little MPs (B-little) intervened biocake layer development, forming more open and porous structures, they also reduced biomass secretion, resulting in flux increases of 13 % in P-large and 40 % in B-little than P-little, respectively. Besides, MFs controlled MPs distribution on the biocake layer, resulting in forming of more rough and open structures. A relatively lower magnetic field of 20 mT facilitated biomass secretion, while a higher magnetic field of 50 mT decreased biomass. Furthermore, applying magnetic fields decreased the ratios of α-helix and β-sheet, and increased random coil percentage. Thus, applying magnetic field mediation would contribute to the flux improvements in I-20 and I-50 by 29 % and 32 % relative to I-0. Economic analysis suggested introducing MPs and MFs to GDM was economically feasible, synergy of MPs and MFs had more economic advantages on the community scale and MPs-assisted GDM had significant economic advantages on both community and household scales. Future works should focus on developing new technologies for the recycling of MPs and membranes. This study provided new insight into the protein secondary structures associated with GDM performance and would encourage new sustainable MFs and MPs-assisted GDM technological developments.

Recycling of perfluorosulfonic acid-based membranes and their Re-application in PEM fuel cells

Polymer electrolyte membrane fuel cells (PEMFC) are lagging in commercialization due to the high cost of noble metal catalysts (e.g., Pt) and perfluorosulfonic acid-based (PFSA) membranes. Recycling and reusing these components at the end of life (EoL) could increase the viability and decrease the environmental impact of PEMFCs. In this work, we demonstrate an environmentally friendly method for reprocessing PFSA membranes based on a hydrothermal treatment using only water as a reactant, which is essential for upscaling to an industrial application. In addition, we focused on the recycling process itself and the membrane's recovery as a water-based dispersion, but also investigated the structural, chemical, and mechanical properties and the electrochemical performance of the membranes after being re-cast from the water-based dispersion (denoted as reprocessed membranes). We investigated two different ionomers, a short-side chain (SSC) ionomer with an equivalent weight of 800 (3M-800EW) and a long-side chain (LSC) ionomer with an equivalent weight of 1000 (3M-1000EW), both obtained from 3 M. Both membrane types could be dispersed in water and reprocessed by hydrothermal treatment. No changes in the chemical structure of the ionomers were observed by subsequent IR, Raman, and NMR spectroscopy. However, thermal and mechanical analyses of the reprocessed membranes showed a deterioration of their mechanical properties. The hydrothermal step increased both the water uptake and retention behavior. We attribute this to the expansion of the water channels observed in the SAXS analysis. Full cell tests under standard (80 °C) and harsher (120 °C & 130 °C) operation conditions demonstrated electrochemical performance for the reprocessed 800EW membranes.

A multi-criteria optimization and decision-making framework of green DME reactor configurations with a focus on high productivity and low CO2 emission rate

The combination of a conventional Dimethyl Ether (DME) reactor with hydrogen perm-selective membrane and effluent recycling creates innovative membrane reactor (MR) configurations that can efficiently improve thermodynamic limits plus low kinetic rates. In the present article, two eco-friendly configurations were applied to the DME conventional reactor (CR) to boost the DME production rate, yield, and selectivity. These configurations comprise two concentric pipes in which in the 1st configuration the fresh synthesis gas is fed to the inner tube side, hydrogen permeates through the reaction zone, and finally the effluent is recycled back to the outer tube, while in the 2nd one, the effluent of outer tube recycled to the inner pipe. The comprehensive 1-D heterogeneous model has an excellent agreement with industrial data. Also, the simulation results reveal that the higher temperature profile in the 2nd configuration is the consequence of more intensification in the reaction zone by H2 injection and proper heat removal which leads to around 9.5 %, 8.22 %, and 10 % increases in the DME production rate, selectivity, and yield compared to CR, respectively. Enjoying reaction output recycling and H2 permeation, the reaction rate of CO and CO2 hydrogenation plus methanol dehydration enhances significantly in the 2nd scheme.According to Euclidean Distance, the optimization results show that the MODE algorithm has a better performance compared to NSGA-II to obtain optimal Pareto Front and also more rapid respect to lower computational time. The LINMAP approach provides a minimum deviation index among all three decision-making algorithms. Employing optimal operation conditions leads to an enhancement of 17 %, 47 %, and 36 % in DME production rate, selectivity, and yield compared to CR. This eco-friendly configuration prevents the emission of 22000 tons of per year CO2 to the atmosphere.

P97/VCP Promotes the Recycling of Endocytic Cargo.

The endocytic pathway is of central importance for eukaryotic cells, as it enables uptake of extracellular materials, membrane protein quality control and recycling, as well as modulation of receptor signaling. While the ATPase p97 (VCP, Cdc48) has been found to be involved in the fusion of early endosomes and endolysosomal degradation, its role in endocytic trafficking is still incompletely characterized. Here, we identify myoferlin (MYOF), a ferlin family member with functions in membrane trafficking and repair, as a hitherto unknown p97 interactor. The interaction of MYOF with p97 depends on the cofactor PLAA previously linked to endosomal sorting. Besides PLAA, shared interactors of p97 and MYOF comprise several proteins involved in endosomal recycling pathways, including Rab11, Rab14, and the transferrin receptor CD71. Accordingly, a fraction of p97 and PLAA localizes to MYOF-, Rab11-, and Rab14-positive endosomal compartments. Pharmacological inhibition of p97 delays transferrin recycling, indicating that p97 promotes not only the lysosomal degradation, but also the recycling of endocytic cargo.