Functional Assays

Bruton€™s tyrosine kinase or BTK, is a non-receptor kinase protein found in hematopoietic and plasma cells. It is involved in functionality, maturation, and apoptosis of B cells, in addition to regulating signals in the MAPK (mitogen-activated protein kinase), PI3K (phosphoinositide 3-kinase) and NF-κB (nuclear factor kappa B) pathways. The BTK pathway has implications for a number of autoimmune disorders including isolated growth hormone deficiency type III and rheumatoid arthritis. BTK inhibitors have been used in the treatment of inflammatory diseases and hematological disorders including cancer. For instance, Ibrutinib (also known as PCI-32765), is used in the clinic for the treatment of CLL (chronic lymphocytic leukemia), MCL (mantle cell lymphoma) and GvHD (graft versus host disease) and other diseases. However, low-selectivity BTK inhibitors have severe side effects, so further refinement is necessary. Development of highly selective BTK inhibitors will lead to greater benefits

Protein Mixed Lineage Leukemia-1 (MLL1, also known as KMT2A) belongs to the SET1/MLL family which consists of six (MLL1-4/KMT2A-2D, SET1A/KMT2F, and SET1B/KMT2G) major methyltransferases in mammals. MLL1 is a histone-H3 lysine-4 (H3K4) methyltransferase that promotes H3K4 mono-/di-/tri-methylation, a conserved trait of euchromatin associated with transcriptional activation. MLL1 is a master regulator for the transcription of many important genes including homeobox (Hox), which has been implicated in hematopoiesis and embryonic development. MLL1 forms a complex with RbBP5 (retinoblastoma-binding protein 5), ASH2L (Absent, small, homeotic disks-2-like), WDR5 (WD40 repeat-containing protein 5), and DPY30 (DumPY protein 30) to catalyze tri-methylation of H3K4. WDR5 represents a therapeutically exploitable target for cancer treatment as it plays a crucial role in MLL1 complex assembly and disassembly. WDR5 has two protein interaction sites: the WDR5-interacting (WIN) binding site and the WD

The Mixed Lineage Leukemia-4 (MLL4, also known as KMT2B) protein belongs to the SET1/MLL family which consists of six (MLL1-4/KMT2A-2D, SET1A/KMT2F, and SET1B/KMT2G) major methyltransferases in mammals. MLL4 is a histone-H3 lysine-4 (H3K4) methyltransferase that promotes H3K4 mono-/di-/tri-methylation, a conserved trait of euchromatin associated with transcriptional activation. MLL4 is a critical player in memory formation. MLL4 forms a complex with RbBP5 (retinoblastoma-binding protein 5), ASH2L (Absent, small, homeotic disks-2-like), WDR5 (WD40 repeat-containing protein 5), and DPY30 (DumPY protein 30) to catalyze methylation of H3K4. WDR5 represents a therapeutically exploitable target for cancer treatment as it plays a crucial role in MLL1 complex assembly and disassembly. WDR5 has two protein interaction sites: the WDR5-interacting (WIN) binding site and the WDR5-binding-motif (WBM) site. MLL1-4 forms the complex via WIN binding site, while RbBP5 is bound to WBM site, which is als

EGFR (epidermal growth factor receptor), also known as ERBB-1 and HER1, is the cell-surface tyrosine kinase receptor for members of the epidermal growth factor family. Its ligands include EGF, TGFα (transforming growth factor alpha), HB-EGF (heparin-binding EGF), betacellulin, amphiregulin, epiregulin and epigen. EGFR exists as an inactive monomer until it gets activated. Upon ligand binding it forms an asymmetric dimer, for instance with HER2 (human epidermal growth factor receptor 2), which induces autophosphorylation, creating binding sites for adaptor proteins such as GRB2 (growth factor receptor-bound protein 2) and/or CBL (Casitas B-lineage lymphoma). EGFR can bind to several adaptor proteins simultaneously and thus activate multiple positive and negative signaling pathways. Overexpression and/or hyperactivation of EGFR kinase is associated with several human cancers such as lung, glioblastoma (GBM), and epithelial tumors of the neck and head, being the most common mutation in GB

TSLP (thymic stromal lymphopoietin) is a protein that functions as a type I cytokine, as an alarmin and growth factor in the immune system. It is involved in type 2 immune responses, T_H2 (T helper 2 cells) responses, and the maturation and recruitment of dendritic cells (DCs), T cells, B cells, neutrophils, mast cells, and other lymphoid cells.  It can be produced by epithelial and stromal cells in lung, skin, and gastric system, but also by DCs, basophils and mast cells. Its expression can be induced by infections, pro-inflammatory cytokines, proteases, and even mechanical injury. For instance, it can be produced in the lungs in response to infection with influenza or rhinovirus. Its role as alarmin can result in increasing inflammation. TSLP is linked to allergic reactions such as asthma, atopic dermatitis, and food allergies, by inducing the expression of OX40L, CD80 and CD86 and stimulating CD4⁺T cells. In 2021, the TLSP-neutralizing antibody tezepelumab was

The BLM helicase, also known as Bloom syndrome protein, is a key enzyme involved in DNA replication and repair (DDR). The BLM helicase is a member of the RecQ family of helicases, which are evolutionarily conserved and found in many organisms, including bacteria, yeast, and humans. It catalyzes the unwinding of duplex DNA with 3' to 5' directionality, driven by the energy generated from ATP hydrolysis. BLM plays a crucial role in maintaining genomic stability by unwinding DNA structures during processes such as DNA replication, recombination, and repair. Mutations in the BLM gene can lead to Bloom syndrome, a rare genetic disorder characterized by growth deficiency, sun-sensitive skin lesions, and an increased risk of cancer. High expression of BLM is found in glioblastoma, and it was found that inhibition of its activity leads to increased susceptibility to treatment with drugs targeting other proteins involved in DDR, such as PARP1 (poly-ADP ribosylation protein 1). The use of BLM in

Cytoplasmic isocitrate dehydrogenase (ICDHc, EC 1.1.1.42) is widely distributed in animals, plants, microorganisms, and cultured cells. It catalyzes the decarboxylation and dehydrogenation of isocitrate to produce α-ketoglutarate, while simultaneously reducing NADP+ to NADPH. ICDHc serves as another significant source of NADPH in the cytoplasm, apart from the pentose phosphate pathway, and its activity often undergoes notable changes under stress conditions. CheKine™ Micro Isocitrate Dehydrogenase Cytoplasmic (ICDHc) Activity Assay Kit is capable of detecting cytosolic isocitrate dehydrogenase (ICDHc) activity in animal and plant tissues, cells, or bacteria, as well as in serum (plasma). The principle behind this involves utilizing ICDHc's catalytic action in reducing NADP+ to NADPH, with the subsequent increase in NADPH concentration being measured at a wavelength of 340 nm.

β-glucuronidase (β-GD), a matrix degradation enzyme involved in tumor invasion and metastasis, is widely found in animal tissues. It has physiological functions such as hydrolyzing sterol glucuronic acid and acidic mucopolysaccharide. The content of this enzyme is high in hepatocytes. In addition, it is rich in gastric cancer, so the determination of β-GD activity in gastric juice is of great significance for the study of gastric cancer. CheKine™ Micro β-glucuronidase (β-GD) Activity Assay Kit can detect animal tissues. In this kit, β-GD catalyzed phenol β-D-glucuronic acid to produce free phenolphthalein, and the enzyme activity was determined by determining the content of phenol.

The activity of plant dehydrogenase (PDHA) is largely reflects the active state of the organism, which can directly indicate the ability of biological cells to degrade its matrix. CheKine™ Micro Plant Dehydrogenase (PDHA) Activity Assay Kit can be used to detect biological samples such as plant tissues. In this kit, The hydrogen acceptor 2,3,5-triphenyl tetrazolium chloride (TTC) generates red triphenyl formazone (TFF) after receiving hydrogen during cell respiration. TFF has a characteristic absorptionpeak at 485 nm, the PDHA activity can quantified by measuring the absorbance at 485 nm.