Search results for "Protein S"

Targeting GSK3 and Associated Signaling Pathways Involved in Cancer

2020

Glycogen synthase kinase 3 (GSK-3) is a serine/threonine (S/T) protein kinase. Although GSK-3 originally was identified to have functions in regulation of glycogen synthase, it was subsequently determined to have roles in multiple normal biochemical processes as well as various disease conditions. GSK-3 is sometimes referred to as a moonlighting protein due to the multiple substrates and processes which it controls. Frequently, when GSK-3 phosphorylates proteins, they are targeted for degradation. GSK-3 is often considered a component of the PI3K/PTEN/AKT/GSK-3/mTORC1 pathway as GSK-3 is frequently phosphorylated by AKT which regulates its inactivation. AKT is often active in human cancer a…

Apollon gene silencing induces apoptosis in breast cancer cells via p53 stabilisation and caspase-3 activation

2009

We analysed the effects of small interfering RNA (siRNA)-mediated silencing of Apollon, a member of the inhibitors of apoptosis protein family, on the proliferative potential and ability of human breast cancer cell lines to undergo apoptosis. In wild-type p53 ZR75.1 cells, Apollon knockdown resulted in a marked, time-dependent decline of cell growth and an increased rate of apoptosis, which was associated with p53 stabilisation and activation of the mitochondrial-dependent apoptotic pathway. Pre-incubation of cells with a p53-specific siRNA resulted in a partial rescue of cell growth inhibition, as well as in a marked reduction of the apoptotic response, indicating p53 as a major player in …

The Interconnecting Hairpin Extension "Arm": An Essential Allosteric Element of Phytochrome Activity

2023

In red-light sensing phytochromes, isomerization of the bilin chromophore triggers structural and dynamic changes across multiple domains, ultimately leading to control of the output module (OPM) activity. In between, a hairpin structure, "arm", extends from an interconnecting domain to the chromophore region. Here, by removing this protein segment in a bacteriophytochrome from Deinococcus radiodurans (DrBphP), we show that the arm is crucial for signal transduction. Crystallographic, spectroscopic, and biochemical data indicate that this variant maintains the properties of DrBphP in the resting state. Spectroscopic data also reveal that the armless systems maintain the ability to respond t…

Varying plant protein sources in the diet of sea bass Dicentrarchus labrax differently affects lipid metabolism and deposition

2010

The liver activity of lipogenic enzymes, the lipid content in various tissues, and plasma lipid levels of major, were measured in sea bass (D. labrax) fed over 96 days either a, fish meal-based control diet or preparations where 70% of fish meal protein was replaced by wheat gluten singly or in combination with pea or soybean meals. Relative to the controls, sea bass fed the wheat gluten-based diet resulted in stimulated lipogenesis in liver and increased lipid deposition in muscle. The opposite occurred when a substantial amount of soybean meal was included in the diet. Mesenteric fat depots were apparently insensitive to major changes in dietary protein source in fish showing similar inta…

Effect of Oxidized Potato Starch on the Physicochemical Properties of Soy Protein Isolate-Based Edible Films

2013

The influence of oxidized starch on the physicochemical properties of cast soy protein isolate films is determined in this study. Films were cast from heated (70 °C for 20 min) alkaline (pH=10) aqueous solutions of 7 % soy protein isolate containing 50 % (by mass) glycerol as a plasticizer and different levels of added oxidized starch (0, 5, 10, 15, and 20 %, by mass). For all types of films, opacity, contact angle, tensile strength, elongation at break, water vapour permeability, measured at 25 °C for four relative humidity differentials (30–53, 30–75, 30–84 and 30–100 %), differential scanning calorimetry and microstructure were determined after conditioning film specimens at 25 °C and 30…

Use of dietary supplements and dietary behaviour among young people who exercise at gyms

2008

Rac1 and PAK1 are upstream of IKK-ε and TBK-1 in the viral activation of interferon regulatory factor-3

2004

The anti-viral type I interferon (IFN) response is initiated by the immediate induction of IFN beta, which is mainly controlled by the IFN-regulatory factor-3 (IRF-3). The signaling pathways mediating viral IRF-3 activation are only poorly defined. We show that the Rho GTPase Rac1 is activated upon virus infection and controls IRF-3 phosphorylation and activity. Inhibition of Rac1 leads to reduced IFN beta promoter activity and to enhanced virus production. As a downstream mediator of Rac signaling towards IRF-3, we have identified the kinase p21-activated kinase (PAK1). Furthermore, both Rac1 and PAK1 regulate the recently described IRF-3 activators, I kappa B kinase- and TANK-binding kina…

Late Activation of Stress-activated Protein Kinases/c-Jun N-terminal Kinases Triggered by Cisplatin-induced DNA Damage in Repair-defective Cells

2011

Although stress-activated protein kinases/c-Jun N-terminal kinases (SAPK/JNK) are rapidly activated by genotoxins, the role of DNA damage in this response is not well defined. Here we show that the SEK1/MKK4-mediated dual phosphorylation of SAPK/JNK (Thr-183/Tyr-185) correlates with the level of cisplatin-DNA adducts at late times (16–24 h) after drug treatment in both human and mouse cells. Transfection of platinated plasmid DNA also caused SAPK/JNK activation. A defect in transcription-coupled nucleotide excision repair resting on a mutation in Cockayne syndrome group B protein promoted the late SAPK/JNK activation following cisplatin exposure. Signaling to SAPK/JNK was accompanied by act…

Activation of astroglial phospholipase D activity by phorbol ester involves ARF and Rho proteins.

2000

Primary cultures of rat cortical astrocytes express phospholipase D (PLD) isoforms 1 and 2 as determined by RT-PCR and Western blot. Basal PLD activity was strongly (10-fold) increased by 4beta-phorbol-12beta,13alpha-dibutyrate (PDB) (EC(50): 56 nM), an effect which was inhibited by Ro 31-8220 (0.1-1 microM), an inhibitor of protein kinase C (PKC), and by brefeldin A (10-100 microg/ml), an inhibitor of ADP-ribosylating factor (ARF) activation. Pretreatment of the cultures with Clostridium difficile toxin B-10463 (0.1-1 ng/ml), which inactivates small G proteins of the Rho family, led to a breakdown of the astroglial cytoskeleton; concomitantly, PLD activation by PDB was reduced by up to 50%…

Metabotropic glutamate receptors activate phospholipase D in astrocytes through a protein kinase C-dependent and Rho-independent pathway.

2003

Metabotropic glutamate receptors (mGluRs) are G protein-coupled receptors that mediate phospholipase D (PLD) activation in brain, but the mechanism underlying this response remains unclear. Here we used primary cultures of astrocytes as a cell model to explore the mechanism that links mGluRs to PLD. Glutamate activated both phospholipase C (PLC) and PLD with equal potency and this effect was mimicked by L-cysteinesulfinic acid, a putative neurotransmitter previously shown to activate mGluRs coupled to PLD, but not PLC, in adult brain. PLD activation by glutamate was dependent on Ca(2+) mobilization and fully blocked by both protein kinase C (PKC) inhibitors and PKC down-regulation, suggesti…