Dipeptidyl peptidase-4 (DPP4) or adenosine deaminase complexing protein 2 (ADCP 2) or T-cell activation antigen CD26 is a serine exopeptidase belonging to the S9B protein family that cleaves X-proline dipeptides from the N-terminus of polypeptides , such as chemokines , neuropeptides , and peptide hormones. The enzyme is a type II transmembrane glycoprotein , expressed on the surface of many cell types. It is also present in serum and other body fluids in a truncated form (sCD26/DPPIV). The soluble CD26 (sCD26) as a tumour marker for the detection of colorectal cancer (CRC) and advanced adenomas. As both a regulatory enzyme and a signalling factor , DPP4 has been evaluated and described in many studies. DPP4 inhibition results in increased blood concentration of the incretin hormones glucagon-like peptide-1 (GLP-1) and gastric inhibitory polypeptide (GIP). This causes an increase in glucose-dependent stimulation , resulting in a lowering of blood glucose levels. Recent studies have shown that DPP4 inhibitors can induce a significant reduction in glycosylated haemoglobin (HbA(1c)) levels , either as monotherapy or as a combination with other antidiabetic agents. Research has also demonstrated that DPP4 inhibitors portray a very low risk of hypoglycaemia development , and are a new pharmacological class of drugs for treating Type 2 diabetes.
TNFRSF21 (death receptor-6, DR6) is an orphan TNF receptor superfamily member and belongs to a subgroup of receptors called death receptors. This type I transmembrane receptor possesses four extracellular cysteine-rich motifs and a cytoplasmic death domain. DR6 is an extensively posttranslationally modified transmembrane protein and that N- and O-glycosylations of amino acids in its extracellular part. DR6 interacts with the adaptor protein TRADD and mediates signal transduction through its death domain, and expression of DR6 in mammalian cells induces activation of both NF-kappaB and JNK and cell apoptosis. DR6 knockout mice have enhanced CD4+ T cell proliferation and Th2 cytokine production, suggested that DR6 serves as an important regulatory molecule in T-helper cell activation, and is involved in inflammation and immune regulation. DR6 is expressed ubiquitously with high expression in lymphoid organs, heart, brain and pancreas. Some tumor cells overexpress DR6, typically in conjunction with elevated anti-apoptosis molecules. DR6 may also be involved in tumor cell survival and immune evasion, which is subject to future investigations.
Tumor necrosis factor receptor superfamily member 21(DR6) is a single-pass type I membrane protein and contains 1 death domain and 4 TNFR-Cys repeats. The protein may activate NF-kappa-B and promote apoptosis and it may activate JNK and be involved in T-cell differentiation.It is required for both normal cell body death and axonal pruning. Trophic-factor deprivation triggers the cleavage of surface APP by beta-secretase to release sAPP-beta which is further cleaved to release an N-terminal fragment of APP (N-APP). N-APP binds TNFRSF21 triggering caspase activation and degeneration of both neuronal cell bodies (via caspase-3) and axons (via caspase-6).
Inserisci la tua e-mail e seleziona le aree di interesse per ricevere le ultime novità, approfondimenti e promozioni.
Seleziona uno o più ambiti di interesse per ricevere comunicazioni più utili e mirate.
2025 TEMA Ricerca - All Rights Reserved.
