Peptídeos

Histone 3 (H3) is one of the four core histones (H2A, H2B, H3 and H4) fundamental in compacting eukaryotic DNA into the nucleosome. The nucleosome arises when 147 base pairs of DNA wrap around a H3-H4 tetramer and two H2A-H2B dimers, forming the histone octamer core. Similar to the other core histone, H3 has a globular domain and a flexible N-terminal domain, 'histone tail' which can undergo modifications such as acetylation, methylation, phosphorylation and ubiquitination. The transcriptional activation or silencing of the chromatin is controlled by ATP-dependent chromatin remodelling factors and histone modifying enzymes which target histone proteins. Both processes function to alter the positioning of the nucleosome, allowing the DNA it to be either available or inaccessible to the transcription machinery.The lysine at position 4 of this peptide has been tri-methylated and it is implicated in studies that this modification may remodel the chromatin so that it is more accessible to transcription factors, which may ultimately increase the level of gene expression. Moreover, the serine at position 10 has been phosphorylated, and studies have suggested that this may induce chromatin condensation, and subsequently repress transcription and gene expression.Histone H3 (1-20) K4Me3, pS10-GG-[Lys(5-FAM)] has a C-terminal GKK linker labelled with 5-Carboxyfluorescein (5-FAM), a widely used green fluorescent tag.

Protease activated receptors (PARs) are a distinctive four-member family of seven transmembrane G protein-coupled receptors (GPCRs) widely expressed in inflammatory cells. PARs are cleaved by certain serine proteases to expose a tethered ligand domain, this ligand domain then binds to and activates the receptors to initiate multiple signalling cascades. These PAR-activating proteases therefore represent PAR agonists. This PAR-2 agonist peptide mimics the sequence of the 'tethered ligand' and is therefore capable of activating the receptor independently of N-terminal proteolysis.SLIGRL-NH2 inhibits the development of airway eosinophilia, hyper-responsiveness and displays bronchodilator activity in allergic mice and also facilitates gastrointestinal transit in mice-in vivo.PAR activation has been linked to inflammation, therefore compounds that mimic or interfere with the PAR-activating processes are attractive therapeutic candidates.

Peptide H-EGPR^NQDWL-OH is a Research Peptide with significant interest within the field academic and medical research. This peptide is available for purchase at Cymit Quimica in multiple sizes and with a specification of your choice.

This peptide represents the reserve sequence of β-amyloid 25-35 (Aβ 25-35) and is used as an inactive control peptide.Aβ has been identified as the key subunit of the extracellular plaques found in the brains of patients with Alzheimer disease (AD) and Down syndrome (DS). Aβ has therefore been extensively studied as a potential target for treatment of AD.Aβ is formed from the cleavage of the large, transmembrane protein- APP (amyloid precursor protein). Cleavage of APP by β- and then γ-secretases results in the formation of Aβ. Aβ can aggregate to produce amyloid-β oligomers, which are thought to be highly neurotoxic. Over time Aβ can further aggregate to produce the characteristic senile plaques present in AD and DS. Aβ can be degraded by enzymes such as neprilysin, insulin degrading enzyme or endothelin converting enzyme. At physiological levels Aβ may be involved in controlling synaptic activity and neuronal survival.

Peptide H-SIIVFNLL^-OH is a Research Peptide with significant interest within the field academic and medical research. This peptide is available for purchase at Cymit Quimica in multiple sizes and with a specification of your choice.

Proapoptotic peptide KLA is a cationic amphipathic peptide that disrupts the mitochondrial membrane. Proapoptotic peptide KLA cannot of its own accord cross eukaryotic cell membranes and is therefore not toxic to the latter. However, KLA has been fused to various protein transduction domains (PTDs) to study its effects in cells. With the fusion of PTDs such as penetratin, KLA becomes highly toxic to cancer cells, it disrupts the mitochondrial cell membrane releasing cytochrome C. This induces cytotoxicity and triggers apoptosis while not effecting normal cells. This selectivity makes KLA-fusion peptides an ideal candidate for further research into cancer treatments as it provides targeted delivery of a highly toxic peptide that only seems to effect cancerous cells. Proapoptotic peptide KLA is provided here to research grade quality, potential PTDs are also available in our catalogue.

Acetyl-Claudin-3 is derived from the tight junction protein Claudin-3 which is encoded by the CLDN3 gene located on chromosome 7q11.23 and can be found within epithelial cell to cell contacts. Structurally, the Claudin family are transmembrane proteins containing two extracellular loops and are involved in maintaining cell polarity and controlling paracellular ion flux.During cancer research reduction in the number of Claudins has been associated with tumour formation. This could be explained using Claudin role in maintaining cell detachment and migration although cancers such as breast and prostate have shown to overexpress both Claudin- 3 and Claudin-4. Similarly in ovarian cancer overexpression of Claudin 3 and 4 is thought to increase the motility of tumour cells and their survival through basement membrane degrading matrix metalloproteinase activation.Both Claudin 3 and 4 have potential to be used as diagnostic markers and their two extracellular loops may be used as targets for antibodies. As receptors for the Clostridium perfringens enterotoxin, Claudin 3 and 4 may have further use in targeting the enterotoxin as a therapeutic for ovarian cancers.