Search results for "Subunit"
showing 10 items of 513 documents
Tyrosinases from crustaceans form hexamers
2002
Tyrosinases, which are widely distributed among animals, plants and fungi, are involved in many biologically essential functions, including pigmentation, sclerotization, primary immune response and host defence. In the present study, we present a structural and physicochemical characterization of two new tyrosinases from the crustaceans Palinurus elephas (European spiny lobster) and Astacus leptodactylus (freshwater crayfish). In vivo, the purified crustacean tyrosinases occur as hexamers composed of one subunit type with a molecular mass of approx. 71kDa. The tyrosinase hexamers appear to be similar to the haemocyanins, based on electron microscopy. Thus a careful purification protocol was…
8-Azido-adenosine 5'-triphosphate as a Photoaffinity Label for Bacterial F1 ATPase
1978
1. 8-Azido-adenosine 5'-triphosphate (n83ATP) is a suitable photoaffinity label for F1 ATPase from Micrococcus luteus. The nucleotide is a substrate in the presence of bivalent cations and inhibits the enzyme irreversibly upon irradiation with ultraviolet light above 300 nm. 2. More than 80% of the label is covalently bound to the beta subunits in the presence of bivalent cations. Labeling and inactivation is decreased by protection with ADP, ATP or adenyl-5'-yl imidodiphosphate. To a much smaller degree the alpha subunits also become labeled. 3. n83AMP does not specifically bind to the beta subunits upon irradiation. Like n83ATP and n83ADP, it also labels the alpha subunits to a small exte…
Bi- and uniciliated ependymal cells define continuous floor-plate-derived tanycytic territories
2017
Multiciliated ependymal (E1) cells line the brain ventricles and are essential for brain homeostasis. We previously identified in the lateral ventricles a rare ependymal subpopulation (E2) with only two cilia and unique basal bodies. Here we show that E2 cells form a distinct biciliated epithelium extending along the ventral third into the fourth ventricle. In the third ventricle floor, apical profiles with only primary cilia define an additional uniciliated (E3) epithelium. E2 and E3 cells' ultrastructure, marker expression and basal processes indicate that they correspond to subtypes of tanycytes. Using sonic hedgehog lineage tracing, we show that the third and fourth ventricle E2 and E3 …
Epigenetic changes in localized gastric cancer: the role of RUNX3 in tumor progression and the immune microenvironment
2016
// Marta Jessica Llorca-Cardenosa 1, * , Tania Fleitas 1, * , Maider Ibarrola-Villava 1 , Maria Pena-Chilet 1 , Cristina Mongort 2 , Carolina Martinez-Ciarpaglini 2 , Lara Navarro 2 , Valentina Gambardella 1 , Josefa Castillo 1 , Susana Rosello 1 , Samuel Navarro 2 , Gloria Ribas 1 , Andres Cervantes 1 1 Medical Oncology, Biomedical Research Institute INCLIVA, University of Valencia, Valencia, Spain 2 Department of Pathology, Biomedical Research Institute INCLIVA, University of Valencia, Valencia, Spain * These authors contributed equally to this work Correspondence to: Gloria Ribas, email: gribas@incliva.es Andres Cervantes, email: andres.cervantes@uv.es Keywords: RUNX3, ARID1A, gastric ca…
The SGLT2 inhibitor empagliflozin improves the primary diabetic complications in ZDF rats
2017
Hyperglycemia associated with inflammation and oxidative stress is a major cause of vascular dysfunction and cardiovascular disease in diabetes. Recent data reports that a selective sodium-glucose co-transporter 2 inhibitor (SGLT2i), empagliflozin (Jardiance®), ameliorates glucotoxicity via excretion of excess glucose in urine (glucosuria) and significantly improves cardiovascular mortality in type 2 diabetes mellitus (T2DM). The overarching hypothesis is that hyperglycemia and glucotoxicity are upstream of all other complications seen in diabetes. The aim of this study was to investigate effects of empagliflozin on glucotoxicity, β-cell function, inflammation, oxidative stress and endothel…
Aging-induced Up-regulation of Nuclear Binding Activities of Oxidative Stress Responsive NF-kB Transcription Factor in Mouse Cardiac Muscle
1996
The accumulation of lipofuscin to cardiomyocytes is a classical parameter of aging and is believed to reflect oxidative stress. NF-kB transcription factor complex is one of the cellular sensors which responds to oxidative stress and regulates gene expression. Our purpose was to study whether aging affects the level and distribution of DNA binding activities of NF-kB transcription factors both in cardiac sarcoplasm and nuclear extracts. We used electrophoretic mobility shift assays (EMSA) to characterize the DNA binding activities of NF-kB and two other transcription factors. AP-1 and Sp-1, in the myocardium of 4 months and 24 months old male and female NMRI-mice. The protein levels of p50, …
Inflammatory activation and endothelial dysfunction markers in patients with permanent atrial fibrillation: A cross-sectional study
2020
In recent years a growing body of evidence supported the role of inflammation in the initiation, maintenance and outcome of atrial fibrillation (AF). Nevertheless, despite a large amount of information, whether AF or the underlying structural heart disease (SHD) is the cause of the inflammatory process is still under debate. We, therefore, sought to determine if the inflammatory process reflect an underlying disease or the arrhythmia 'per se'. We evaluated plasma levels of soluble Interleukin 2 Receptor Alpha (sIL-2Rα), TNF-α and IL-18 in 100 consecutive patients with permanent AF, (43 with a SHD and 57 without a SHD) compared to 121 age and sex-matched controls which had normal sinus rhyth…
Organotypic rat cerebellar slice culture as a model to analyze the molecular pharmacology of GABAA receptors
2002
The preservation of the neuronal circuitry in rat cerebellar slice cultures provides an advantage in monitoring the development and characterizing the pharmacology of GABA(A) receptor subtypes. Sprague-Dawley rats, 8-11 days of age, were decapitated, their cerebella were cut into 400-microm slices and transferred into culture dishes. Cell viability and organotypic cerebellar organization of the culture remained well preserved up to 3 weeks. Autoradiographic procedures were introduced in these advanced culture technique and employed [(3)H]Ro 15-4513 in the absence and presence of 10 microM diazepam to visualize all benzodiazepine (BZD) and diazepam-insensitive (DIS) binding sites, respective…
Expression and developmental regulation of the cystine/glutamate exchanger (xc-) in the rat.
2007
The cystine/glutamate exchanger (antiporter x c − ) is a membrane transporter involved in the uptake of cystine, the rate-limiting amino acid in the synthesis of glutathione. Recent studies suggest that the antiporter plays a role in the slow oxidative excitotoxity and in the pathological effects of β-N-oxalylamino-l-alanine, the molecule responsible for neurolathyrism, a neurotoxic upper motor neuron disease. The mouse cystine/glutamate exchanger has been cloned and showed to be composed of two distinct proteins, one of which being a novel protein, named xCT, of 502 amino acids and 12 putative trans-membrane domains. We have generated and purified a polyclonal antibody to mouse xCT and stu…
De novo loss-of-function KCNMA1 variants are associated with a new multiple malformation syndrome and a broad spectrum of developmental and neurologi…
2019
Abstract KCNMA1 encodes the large-conductance Ca2+- and voltage-activated K+ (BK) potassium channel α-subunit, and pathogenic gain-of-function variants in this gene have been associated with a dominant form of generalized epilepsy and paroxysmal dyskinesia. Here, we genetically and functionally characterize eight novel loss-of-function (LoF) variants of KCNMA1. Genome or exome sequencing and the participation in the international Matchmaker Exchange effort allowed for the identification of novel KCNMA1 variants. Patch clamping was used to assess functionality of mutant BK channels. The KCNMA1 variants p.(Ser351Tyr), p.(Gly356Arg), p.(Gly375Arg), p.(Asn449fs) and p.(Ile663Val) abolished the …