(YTH) domain-containing family proteins (YTHDF)

GPCRs are a large family of cell surface receptors that respond to a variety of external signals. Binding of a signaling molecule to a GPCR results in G protein activation, which in turn triggers the production of any number of second messengers. GPCRs play an important role in the human body, and increased understanding of these receptors has greatly affected modern medicine. In fact, researchers estimate that between one-third to one-half of all approved drugs act by binding to GPCRs. GPCRs are a large group of drug targets in drug discovery.

MCE provides a unique collection of 3,070 small molecules targeting GPCRs that can be used in the screening for various GPCRs-related research and drug development projects.

Cysteine proteases (CPs), a key enzyme family regulating physiological metabolism and mediating pathological processes (e.g., abnormal bone resorption, tumour invasion, and pathogen infection), represent a core therapeutic target for disease intervention via the development of specific inhibitors. Currently reported CP covalent inhibitors encompass diverse structural types, including epoxides, aziridine, and activated double bonds (vinyl sulphones, α,β-unsaturated ketones), providing clear structural references for the development of novel CP covalent inhibitors.

This compound library contains multiple warheads that specifically target cysteine proteases, serving as a powerful tool for the efficient discovery of novel covalent inhibitors against this enzyme family.

MAPK families play an important role in complex cellular programs like proliferation, differentiation, development, transformation, and apoptosis. In mammalian cells, four MAPK families have been clearly characterized: ERK1/2, C-Jun N-terminal kinse/stress-activated protein kinase (JNK/SAPK) , p38 kinase and ERK5. They respond to different signals. Each MAPK-related cascade consists of three enzymes that are activated in series: a MAPK kinase kinase (MAPKKK), a MAPK kinase (MAPKK) and a MAP kinase (MAPK). MAPK signaling pathways has been implicated in the development of many human diseases including Alzheimer's disease (AD), Parkinson's disease (PD), amyotrophic lateral sclerosis (ALS) and various types of cancers.

MCE designs a unique collection of 851 MAPK signaling pathway inhibitors that act as a useful tool for MAPK-related drug screening and disease research.

Protein phosphorylation is a key post-translational modification underlying the regulation of many cellular processes. Phosphatases and kinases contribute to the regulation of protein phosphorylation homeostasis in the cell. This reversible regulation of protein phosphorylation is critical for the proper control of a wide range of cellular activities, including cell cycle, proliferation and differentiation, metabolism, cell-cell interactions, etc.

Protein phosphatases have evolved in separate families that are structurally and mechanistically distinct. Based on substrate specificity and functional diversity, protein phosphatases are classified into two superfamilies: Protein serine/threonine phosphatases and Protein tyrosine phosphatases. Ser/Thr phosphatases are metalloenzymes belonging to two major gene families termed PPP (phosphoprotein phosphatase) and PPM (metal-dependent protein phosphatases), whereas protein tyrosine phosphatases (PTPs) belong to distinct classes of enzymes that utilize a phospho-cysteine enzyme intermediate as a part of their catalytic action.

MCE supplies a unique collection of 159 phosphatase inhibitors that mainly targeting protein tyrosine phosphatases (PTPs) and serine/threonine-specific protein phosphatases. MCE Phosphatase Inhibitor Library is a useful tool for phosphatase drug discovery and related research.

Apoptosis is an ordered and orchestrated cellular process that occurs in physiological and pathological conditions, which is also called programmed cell death (PCD). Apoptosis plays a crucial role in developing and maintaining the health of the body by eliminating old cells, unhealthy cells and unnecessary cells. Too little or too much apoptosis contribute to many diseases. When apoptosis does not work correctly, cells that should be eliminated may persist and become immortal, for example, in cancer and leukemia. When apoptosis works overly well, it kills too many cells and inflicts grave tissue damage. This is the case in strokes and neurodegenerative disorders such as Alzheimer's, Huntington's, and Parkinson's disease.

MCE designs a unique collection of 3,143 apoptosis-related compounds mainly focusing on the key targets in the apoptosis signaling pathway and can be used in the research of apoptosis signal pathway and related diseases.

Stem cells, which are found in all multi-cellular organisms, can divide and differentiate into diverse special cell types and can self-renew to produce more stem cells. To be useful in therapy, stem cells must be converted into desired cell types as necessary which is called induced differentiation or directed differentiation. Understanding and using signaling pathways for differentiation is an important method in successful regenerative medicine. Small molecules or growth factors induce the conversion of stem cells into appropriate progenitor cells, which will later give rise to the desired cell type. There is a variety of signal molecules and molecular families that may affect the establishment of germ layers in vivo, such as fibroblast growth factors (FGFs); the wnt family or superfamily of transforming growth factors β (TGFβ) and bone morphogenetic proteins (BMP). Unfortunately, for now, a high cost of recombinant factors is likely to limit their use on a larger scale in medicine. The more promising technique focuses on the use of small molecules. These small molecules can be used for either activating or deactivating specific signaling pathways. They enhance reprogramming efficiency by creating cells that are compatible with the desired type of tissue. It is a cheaper and non-immunogenic method.

MCE Differentiation Inducing Compound Library contains a unique collection of 2,080 compounds that act on signaling pathways for differentiation. These compounds are potential stimulators for induced differentiation. This library is a useful tool for researching directed differentiation and regenerative medicine.

Agonistic drugs activate or stimulate their receptors, triggering responses that increase or decrease cell activity. The highly selective activators can act on specific biological or molecular targets, while non-selective activators may interfere with multiple targets or targets simultaneously. The highly selective activators reduce the likelihood of these non-specific effects by targeting specific targets, making research more precise and reliable. The Highly Selective Activators Library contains 1,869 compounds, covering multiple targets and subtypes, such as GPCR protein family, Ion channel, multiple kinases, etc. The Highly Selective Activators Library is an effective tool for screening different phenotypes.

Protein Kinases (PTKs) are a class of phosphotransferases that phosphorylate proteins. Protein kinases participate in many signal transduction pathways including those involved with growth, differentiation, and cell division. Protein kinase not only plays an important role in the process of cell activation, but also its abnormal expression is closely related to the pathogenesis of many diseases. So far, the protein kinase family has become one of the most important drug targets. The most common drug targets include ALK, B-Raf, BCR-Abl, EGFR, and VEGFR.

MCE designs a unique collection of 3,761 bioactive compounds targeting protein kinases, which is an important tool for the development of drug targeting protein kinases.

According to reports, most known kinase inhibitors exert their effects through competitive binding in highly conserved ATP pockets. Although genetic techniques such as RNA interference can inactivate specific genes, most kinases are multi domain proteins, each of which has an independent function. Highly selective inhibitors have higher efficiency than non-selective inhibitors, and the selectivity to the target is at least 100 times higher. Therefore, ensuring the validation of targets with the most selective inhibitors is crucial for a more thorough understanding of the pharmacology of the kinase field. The Highly Selective Inhibitors Library contains 5,640 compounds, covering multiple targets and subtypes, such as GPCR protein family, Ion channel, multiple kinases, etc. The Highly Selective Inhibitors Library is an effective tool for screening different phenotypes

Adult stem cells are important for tissue homeostasis and regeneration due to their ability to self-renew and generate multiple types of differentiated daughters. Self-renewal is reflected by their capacity to undergo multiple/limitless divisions. Several signaling pathways are involved in self-renewal of stem cells, that is, Notch, Wnt, and Hedgehog pathways or Polycomb family proteins. Recent studies mainly focus on cancer stem cell (CSCs), induced pluripotent stem cell (iPSCs), neural stem cell and maintenance of embryonic stem cell pluripotency. Among them, CSCs have been believed to be responsible for tumor initiation, growth, and recurrence that have implications for cancer therapy.

MCE owns a unique collection of 2,301 compounds that can be used for stem cell regulatory and signaling pathway research.

5-HT receptors, also called Serotonin receptors, are a group of G protein-coupled receptors (GPCRs) and ligand-gated ion channels (LGICs) found in the central and peripheral nervous systems. These receptors are now classified into seven families, 5-HT1–7, comprising a total of 14 structurally and pharmacologically distinct mammalian 5-HT receptor subtypes. The 5-HT receptors influence various biological and neurological processes such as aggression, anxiety, appetite, cognition, learning, memory, mood, nausea, sleep, andthermoregulation. The serotonin receptors are the target of a variety of pharmaceutical drugs, including many antidepressants, antipsychotics, anorectics, antiemetics, gastroprokinetic agents, antimigraine agents, hallucinogens, and entactogens.

MCE 5-HT Receptor Compound Library consists of 369 5-HT receptor inhibitors and activators, which can be used for neuropsychiatric disorders drugs discovery.

Orthopoxvirus is a genus of viruses in the family Poxviridae and subfamily Chordopoxvirinae. The orthopoxvirus genus consists of 12 viruses including variola virus, vaccinia virus (VV), cowpox viruses (CV), monkeypox virus, and camelpox virus. Smallpox has been eradicated worldwide in 1980, but some other orthopoxvirus, such as monkeypox virus, are still threats to human health.

There are not many drugs available for orthopoxvirus treatment. The only product currently available for treatment of complications of Orthopoxvirus infection is vaccinia immunoglobulin (VIG). In 2021, brincidofovir was approved by FDA for the treatment of smallpox and tecovirimat was approved by EMA for the treatment of monkeypox in 2022. A few active compounds including interferon and interferon inducers, and a variety of nucleosides or nucleotides have been reported to have activity against orthopoxvirus.

MCE carefully prepared a unique collection of 37 compounds reported with the anti- orthopoxvirus activity which can be used for drug screening and other research about orthopoxvirus.

Protein tyrosine kinases (PTKs) are key signaling molecules and important drug targets. Two classes of PTKs are present in cells: the transmembrane receptor PTKs (RTKs) and the nonreceptor PTKs. The RTK family includes the receptors for insulin and for many growth factors, such as EGFR, FGFR, PDGFR, VEGFR, and NGFR. RTKs are transmembrane glycoproteins that are activated by the binding of their ligands, and they transduce the extracellular signal to the cytoplasm by phosphorylating tyrosine residues on the receptors themselves (autophosphorylation) and on downstream signaling proteins. Their principal functions of PTKs involve the regulation of multicellular aspects of the organism. Cell to cell signals concerning growth, differentiation, adhesion, motility, and death are frequently transmitted through tyrosine kinases. In humans, tyrosine kinases have been demonstrated to play significant roles in the development of many disease states, including diabetes and cancers.

MCE designs a unique collection of 1,420 compounds that act as a useful tool for PTKs-related drug screening and disease research.

Cysteine proteases (CPs), a key enzyme family regulating physiological metabolism and mediating pathological processes (such as abnormal bone resorption, tumour invasion, and pathogen infection), represent a core therapeutic target for developing specific inhibitors in disease intervention. Currently reported CP inhibitors primarily achieve their inhibitory function by precisely binding to CP active pockets (e.g., S1-S4 non-primed regions or S1'-S2' primed regions) and forming covalent/non-covalent interactions with the active site cysteine residues, providing clear structural references for the development of novel inhibitors.

This compound library, designed based on the core strategy of "similarity-based known active structures", contains over 200 cysteine protease inhibitors. Leveraging AI-driven molecular screening technology, it retains the critical pharmacological and shape features of reported CP inhibitors, serving as a specialized tool for efficiently discovering novel cysteine protease inhibitors.

A diverse compound library with favorable ADMET properties (Absorption, Distribution, Metabolism, Excretion, and Toxicity) is crucial in drug discovery. Early evaluation of ADMET properties allows for the exclusion of molecules with unfavorable profiles at the initial stages, thereby reducing the risk of late-stage development failures, lowering R&D costs, and accelerating optimization of lead compounds. Based on predictions from ADMET-related AI algorithms, the compounds in this library are predicted to exhibit favorable oral bioavailability (F > 30%), reasonable plasma protein binding (PPB < 98%), minimized CYP3A4 inhibition potential (inhibition probability < 50%, CYP3A4 is the most critical drug-metabolizing enzyme in the cytochrome P450 family) , low toxicity profiles, with 140 potentially toxic substructures pre-identified and excluded via substructure searching to eliminate compounds containing hazardous fragments. The diversity library enables broad applicability in high-throughput screening (HTS) and high-content screening (HCS).

Hepatitis C virus (HCV) is a hepatotropic enveloped positive- strand RNA virus (family Flaviviridae) that infects the parenchymal cells of the liver. HCV infection is a significant public health burden. Globally, an estimated 71 million people have chronic hepatitis C virus infection. A significant number of those who are chronically infected will develop cirrhosis or liver cancer. To date, there is no vaccine against HCV, and combination pegylated alpha interferon (pIFN-) and ribavirin, the main standard-of-care treatment for HCV, is effective in only a subset of patients and is associated with a wide spectrum of toxic side effects and complications. More recently, new therapeutic approaches that target essential components of the HCV life cycle have been developed, including direct-acting antiviral (DAA) that specifically block a viral enzyme or functional protein and host-targeted agents (HTA) that block interactions between host proteins and viral components that are essential to the viral life cycle. However, the genetic diversity of HCV viruses and the stage of liver disease (i.e., cirrhosis) are revealing themselves as obstacles for effective, pan-genotypic treatments. There still exists a need for the discovery and development of new HCV inhibitors. In particular, since the future of HCV therapy will likely consist of a cocktail approach using multiple inhibitors that target different steps of infection, new antivirals targeting all steps of the viral infection cycle.

MCE offers a unique collection of 362 compounds with identified and potential anti-HCV activity. MCE Anti- Hepatitis C Virus Compound Library is a useful tool for discovery new anti-HCV drugs and other anti-infection research.