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Membrane receptors, also known cell surface receptors or transmembrane receptors, are transmembrane proteins embedded into the plasma membrane which play an essential role in maintaining communication between the internal processes within the cell and various types of extracellular signals. They act in cell signaling by receiving (binding to) extracellular molecules, which are also called ligands. These extracellular molecules include hormones, cytokines, growth factors, neurotransmitters, lipophilic signaling molecules such as prostaglandins, and cell recognition molecules.

There are three kinds of membrane receptors: ion channel-linked receptors, enzyme-linked receptors and G-protein-linked receptors. They play important roles in keeping human normal physiologic processes. GPCRs and ion channels are important drug targets in drug discovery.

MCE provides a unique collection of 4626 compounds targeting a variety of membrane receptors. MCE Membrane reeptor-targeted Compound Library can be used for membrane receptor-focused screening and drug discovery.

Antibody-Drug Conjugates (ADCs), a new class of treatment for cancer, are composed with a monoclonal antibody, a linker and a cytotoxic agent also referred to as a payload. To date, several ADCs have received market approval and more than 60 ADCs are currently in clinical trials. ADCs are one of the fastest growing classes of oncology drugs worldwide.

The payload or cytotoxic agent is the most important unit in the ADC. ADC has the capability to kill cancer cell depending on the potency of the payload. MCE provides 90 highly potent cytotoxins that contain auristatin derivatives, maytansinoids, calicheamicin, duocarmycin, pyrrolobenzodiazepines (PBDs), etc.

PROTACs (Proteolysis-targeting chimeras) is a class of molecules that utilize ubiquitin-proteasome system (UPS) to ubiquitinate and degrade target proteins. The PROTACs molecule consists of two ligands joined by a linker. The one-to-one interaction between PROTACs and target proteins determines the high efficiency of PROTACs, making it a potential molecule for targeted protein degradation (TPD) therapy.

MCE supplies a unique collection of 225 PROTACs that effectively degrade target proteins with more powerful screening capability. MCE PROTAC Library is a useful tool for signal pathway research, protein degradation therapy research, drug discovery and drug repurposing, etc.

Inflammation promotes physiological and pathological processes by the activation of the immune system, local vascular system, and various cells within the damaged tissue. Accumulating epidemiological and clinical evidence shows that chronic inflammation is causally linked to various human diseases, including cerebrovascular, cardiovascular, joint, cutaneous, pulmonary, blood, liver, and intestinal diseases as well as diabetes.

Various natural products from Traditional Chinese Medicine (TCM) have been shown to safely suppress proinflammatory pathways and control inflammation-associated disease. MCE designs a unique collection of 1057 Traditional Chinese Medicine active compounds with anti-inflammatory activity, which are derived from Coptis chinensis, Radix isatidis, Flos Lonicerae, Forsythia suspensa, etc. MCE Anti-inflammatory Traditional Chinese Medicine Active Compound Library is a useful tool for discovery anti-inflammatory drugs from TCM.

The cytoskeleton is responsible for contraction, cell motility, movement of organelles and vesicles through the cytoplasm, cytokinesis, intracellular signal transduction, and many other functions that are essential for cellular homeostasis and survival. It accomplishes these tasks through three basic structures: F-actin, microtubules, and intermediate filaments (IFs). The cytoskeleton is a dynamic structure where the three major filaments and tubules are under the influence of proteins that regulate their length, state of polymerization, and level of cross-linking. Since cytoskeleton is involved in virtually all cellular processes, cytoskeletal protein aberrations are the underlying reason for many pathological phenotypes, including several cardiovascular disease syndromes, neurodegeneration, cancer, liver cirrhosis, pulmonary fibrosis, and blistering skin diseases.

MCE designs a unique collection of 1242 cytoskeleton-related compounds mainly focusing on the key targets in the cytoskeleton signal pathway and can be used in the research of cytoskeleton signal pathway and related diseases.

Accumulating evidence has revealed that intestinal microbiota play an important role in human health and disease, including cardiovascular diseases, inflammatory bowel disease, diabetes, obesity, cancer, and depression, etc. Changes in the composition of gut microbiota associated with disease, referred to as dysbiosis, have been linked to pathologies. Indeed, the gut microbiome functions like an endocrine organ, generating bioactive metabolites which play important roles in human metabolism, health, and disease. Gut microbiome has become a novel therapeutic target for many diseases. Analysis and identification of gut microbial metabolite will contribute to the development of therapeutic methods.

In order to meet the need of gut microbiome research, MCE carefully selected a unique collection of 500 gut microbial metabolites. MCE gut microbial metabolite library is a powerful tool for gut microbiome research and gut microbiome -related drug discovery.

Proteolysis-targeting chimera (PROTAC) has been developed to be a useful technology for targeted protein degradation. PROTACs consist of a ligand for E3 ligase (E3 ligase binder), a linker and a ligand (mostly small-molecule inhibitor) for protein of interest（target binder）. Upon binding to the target protein, the PROTACs can recruit E3 for target protein ubiquitination, which is subjected to proteasome-mediated degradation. Therefore, PROTACs execute their functions by degrading the target proteins rather than inhibiting them, which has a great superiority in overcoming resistance caused by target mutation or overexpression. To date, PROTAC technology has been applied to a variety of targets, including AR, ER, BTK, BET, and BCR-ABL to overcome resistance.

MCE carefully prepared a unique collection of 40 ligands for target proteins, which have been reported to be used in PROTAC design. MCE Target Protein Ligand Library is a useful tool for PROTAC development.

Endoplasmic reticulum (ER) contributes to the production and folding of approximately one third of cellular proteins, and is thus inextricably linked to the maintenance of cellular homeostasis and the fine balance between health and disease. However, some adverse factors negatively impact ER functions and protein synthesis, resulting in the activation of Endoplasmic reticulum stress (ER stress, ERS) and unfolded protein response (UPR) signaling pathways. The UPR is triggered when ER protein folding capacity is overwhelmed by cellular demand and the UPR initially aims to restore ER homeostasis and normal cellular functions. However, if this fails, then the UPR triggers cell death. Chronic ER stress and defects in UPR signaling are emerging as key contributors to a growing list of human diseases, including diabetes, neurodegeneration and cancer.

MCE Endoplasmic Reticulum Stress Compound Library contains 220 ER stress-related compounds that mainly target PERK, IRE1, ATF6, etc. MCE ER stress library is a useful tool for researching ER stress and related diseases.

The developmental proteins Hedgehog, Notch and Wnt are key regulators of cell fate, proliferation, migration and differentiation in several tissues. Their related signaling pathways are frequently activated in tumors, and particularly in the rare subpopulation of cancer stem cells. The Wnt signaling pathway is a conserved pathway in animals. Deregulated Wnt signaling has catastrophic consequences for the developing embryo and it is now well appreciated that defective Wnt signaling is a causative factor for a number of pleiotropic human pathologies, including cancer. Hedgehog signaling pathway is linked to tumorigenesis and is aberrantly activated in a variety of cancers. The Notch signaling pathway is a highly conserved cell signaling system present in most animals. It plays an important role in cell-cell communication, and further regulates embryonic development.

MCE designs a unique collection of 349 Wnt/Hedgehog/Notch signaling pathway-related small molecules. Wnt/Hedgehog/Notch Compound Library serves as a useful tool for stem cell research and anti-cancer drug screening.

Proteolysis-targeting chimera (PROTAC) has been developed to be a useful technology for targeted protein degradation. PROTACs consist of a ligand for E3 ligase (E3 ligase binder), a linker and a ligand (mostly small-molecule inhibitor) for protein of interest（target binder）. Upon binding to the target protein, the PROTACs can recruit E3 for target protein ubiquitination, which is subjected to proteasome-mediated degradation.

Although there are more than 600 E3 ubiquitin ligases, only several with small molecule ligands have been used for designing PROTACs, including Skp1-Cullin-F box complex containing Hrt1 (SCF), Von Hippel-Lindau tumor suppressor (VHL), Cereblon (CRBN), inhibitor of apoptosis proteins (IAPs), and mouse double minute 2 homolog (MDM2).

MCE carefully prepared a unique collection of 88 ligands for E3 ligase, which have been reported to be used in PROTAC design. MCE E3 ligase ligand library is a useful tool for PROTAC development.

Most of molecules enter or leave cells mainly via membrane transport proteins, which play important roles in several cellular functions, including cell metabolism, ion homeostasis, signal transduction, the recognition process in the immune system, energy transduction, etc. There are three major types of transport proteins, ATP-powered pumps, channel proteins and transporters. Transport proteins such as channels and transporters play important roles in the maintenance of intracellular homeostasis, and mutations in these transport protein genes have been identified in the pathogenesis of a number of hereditary diseases. In the central nervous system, ion channels have been linked to, but not limited to, many diseases such asataxias, paralyses, epilepsies, and deafness. This indicates the roles of ion channels in the initiation and coordination of movement, sensory perception, and encoding and processing of information. Ion channels are a major class of drug targets in drug development.

MCE designs a unique collection of 1392 smal-molecule modulators that can be used for the research of Ion Channel and Membrane Transporter or high throughput screening (HTS) related drug discovery.

Nuclear factor-κB (NF-κB)/Rel proteins include NF-κB2 p52/p100, NF-κB1 p50/p105, c-Rel, RelA/p65, and RelB. These proteins function as dimeric transcription factors that regulate the expression of genes and influence a broad range of biological processes including innate and adaptive immunity, inflammation, stress responses, B-cell development, and lymphoid organogenesis. NF-κB plays a key role in regulating the immune response to infection. In addition, activation of the NF-κB pathway is involved in the pathogenesis of chronic inflammatory diseases, such as asthma, rheumatoid arthritis, and inflammatory bowel disease. Incorrect regulation of NF-κB has been linked to cancer, inflammatory and autoimmune diseases, septic shock, viral infection, and improper immune development.

MCE owns a unique collection of 798 small molecule compounds that can be used in the research of NF-κB signaling pathway or high throughput screening (HTS) related drug discovery.

Liver cancer is one of the leading malignancies which occupies the second position in cancer deaths worldwide, becoming serious threat to human health. Hepatocellular carcinoma (HCC), also known as hepatoma is the most common type accounting for approximately 90% of all liver cancers.

Current evidence indicates that during hepatocarcinogenesis, two main pathogenic mechanisms prevail: (1) cirrhosis associated with hepatic regeneration after tissue damage caused by hepatitis infection, toxins or metabolic influences, and (2) mutations occurring in single or multiple oncogenes or tumor suppressor genes. Both mechanisms have been linked with alterations in several important cellular signaling pathways. These include the RAF/MEK/ERK pathway, PI3K/AKT/mTOR pathway, WNT/b-catenin pathway, insulin-like growth factor pathway, c-MET/HGFR pathway , etc.

MCE offers a unique collection of 1798 compounds with identified and potential anti-liver cancer activity. MCE anti-liver cancer compound library is a useful tool for anti-liver cancer drugs screening and other related research.

MCE High-Affinity Iodoacetyl Agarose, a 4% highly cross-linked agarose reagent coupled with a derivative of iodoacetic acid, is ideal for conjugating sulfhydryl-containing peptide or protein for subsequent affinity purification.

MCE Streptavidin Agarose 6FF, a 6% highly cross-linked agarose reagent coupled with recombinant streptavidin, is an affinity chromatography medium for separation and purification of biotinylated peptides, antibodies, lectins, etc. The total binding capacity of Streptavidin Agarose 6FF is more than 200 nmol of D-Biotin/mL settled resin.