Search results for "polypeptide"
showing 10 items of 51 documents
Identification and optimization of small molecule antagonists of vasoactive intestinal peptide receptor-1 (VIPR1).
2012
Identification, synthesis and structure-activity relationship of small-molecule VIPR1 antagonists encompassing two chemical series are described.
Changes in polypeptide profiles of two pea genotypes inoculated with the arbuscular mycorrhizal fungus Glomus mosseae
1994
The symbiotic interaction between pea roots ('Pisum sativum' L.) and the endomycorrhizal fungus 'Glomus mosseae' should lead to specific gene expression of both symbionts. In order to detect symbiosis-related proteins (endomycorrhizins), we used two-dimensional polyacrylamide gel electrophoresis (2D-PAGE) after phenolic extraction of total soluble proteins. Furthermore, to better characterize the molecular changes after fungal infection, two pea genotypes available in our laboratory were used: cv. Frisson (myc⁺) and an isogenic mycorrhiza-resistant mutant (myc⁻). The latter prevents intraradical fungal development. Several differences were observed in polypeptide patterns of silver-stained …
Fibril formation and toxicity of the non-amyloidogenic rat amylin peptide.
2012
Full-length native rat amylin 1-37 has previously been widely shown to be unable to form fibrils and to lack the toxicity of the human amylin form leading to its use as a non-amyloidogenic control peptide. A recent study has suggested that rat amylin 1-37 forms amyloidogenic β-sheet structures in the presence of the human amylin form and suggested that this property could promote toxicity. Using TEM analysis we show here fibril formation by synthetic rat amylin 1-37 and 8-37 peptides when the lyophilized HPLC purified peptides are initially dissolved in 20 mM Tris-HCl. Dissolution of synthetic rat amylin 1-37 and 8-37 peptides in H(2)O or phosphate buffered saline failed to produce fibrils.…
A mutation in the second intracellular loop of the pituitary adenylate cyclase activating polypeptide type I receptor confers constitutive receptor a…
2000
AbstractThe pituitary adenylate cyclase activating polypeptide (PACAP) type I receptor belongs to the glucagon/secretin/vasoactive intestinal polypeptide (VIP) receptor family. We mutated and deleted an amino acid residue (E261) which is located within the second intracellular loop of the rat PACAP type I receptor and which is highly conserved among the receptor family. The wild-type receptor and the mutant receptors were efficiently expressed at the surface of COS-7 cells at nearly the same level and revealed the same high affinity for the agonist PACAP-27. The cAMP contents of COS cells transfected with the E261A, E261Q, and the deletion mutant receptor were 4.6-, 5.7-, and 6.7-fold highe…
A CRF-Producing and -Secreting Tumor of the Lung
1986
Corticotropin-releasing factor (CRF) has recently been isolated from ovine hypothalamus, characterized chemically, and synthesized. Upton and Amatruda (1971) first suggested that CRF-like activity occurred in neoplastic tissues, and Hashimoto et al. (1980) subsequently detected CRF-like activity in an extract of an ACTHproducing nephroblastoma. Recently, Carey et al. (1984) and Asa et al. (1984) used immunocytochemical techniques to demonstrate CRF in postmortem tumor material obtained from patients with a carcinoma of the prostate and an intrasellar gangliocytoma.
VIPoma and PPoma
2015
Gastrinomas are rare tumors of the neuroendocrine system, occurring within the pancreas and duodenum. The annual incidence is estimated at 0.5 per million of the population [1]. Overproduction of gastrin by these tumors produces a sustained increase in gastric acid secretion, leading to clinical manifestations of complicated peptic ulcer disease known as the Zollinger-Ellison syndrome (ZES) [2]. Although most gastrinomas grow slowly, over 60 % are malignant and 25 % show rapid aggressive behavior [3-5]. Most commonly gastrinomas metastasize to regional lymph nodes and the liver, and it is this malignant potential which has become increasingly important since the introduction of effective me…
Molecular and Translational Classifications of DAMPs in Immunogenic Cell Death
2015
The immunogenicity of malignant cells has recently been acknowledged as a critical determinant of efficacy in cancer therapy. Thus, besides developing direct immunostimulatory regimens, including dendritic cell-based vaccines, checkpoint-blocking therapies, and adoptive T-cell transfer, researchers have started to focus on the overall immunobiology of neoplastic cells. It is now clear that cancer cells can succumb to some anticancer therapies by undergoing a peculiar form of cell death that is characterized by an increased immunogenic potential, owing to the emission of the so-called "damage-associated molecular patterns" (DAMPs). The emission of DAMPs and other immunostimulatory factors by…
Regulatory networks underlying mycorrhizal development delineated by genome-wide expression profiling and functional analysis of the transcription fa…
2017
Background: Ectomycorrhizal (ECM) fungi develop a mutualistic symbiotic interaction with the roots of their host plants. During this process, they undergo a series of developmental transitions from the running hyphae in the rhizosphere to the coenocytic hyphae forming finger-like structures within the root apoplastic space. These transitions, which involve profound, symbiosis-associated metabolic changes, also entail a substantial transcriptome reprogramming with coordinated waves of differentially expressed genes. To date, little is known about the key transcriptional regulators driving these changes, and the aim of the present study was to delineate and functionally characterize the trans…
Well-defined polypeptide-based systems as non-viral vectors for cytosolic delivery
2017
A convenient cytosolic drug delivery constitutes a very powerful tool for the treatment and/or prevention of several relevant human diseases. Along with recent advances in therapeutic technologies based on biomacromolecules (e.g. oligonucleotides or proteins), we also require the development of technologies which improve the transport of therapeutic molecules to the cell of choice. This has led to the emergence of a variety of promising methods over the last 20 years. Despite significant progress, these methods still suffer from several shortcomings including low/variable delivery efficiency, high cytotoxicity, and perhaps most importantly, ineffective endosomal/lysosomal escape. In this co…
Trans -Cyclooctene-Functionalized PeptoBrushes with Improved Reaction Kinetics of the Tetrazine Ligation for Pretargeted Nuclear Imaging
2020
Tumor targeting using agents with slow pharmacokinetics represents a major challenge in nuclear imaging and targeted radionuclide therapy as they most often result in low imaging contrast and high radiation dose to healthy tissue. To address this challenge, we developed a polymer-based targeting agent that can be used for pretargeted imaging and thus separates tumor accumulation from the imaging step in time. The developed targeting agent is based on polypeptide-graft-polypeptoid polymers (PeptoBrushes) functionalized with trans-cyclooctene (TCO). The complementary In-111-labeled imaging agent is a 1,2,4,5-tetrazine derivative, which can react with aforementioned TCO-modified PeptoBrushes i…