Signal transduction

receptor, these are held in constrained form, but on binding of insulin at the ligand binding site on 2α subunits, constraints are freed, tyrosine kinase phosphorylate and activate each other, and then they phosphorylate other proteins in the signal transduction pathway.…

differentiation of chondrocytes in bones; moreover, the negative feedback of chondrocyte production provided by FGFR3 regulates bone growth (7). Once the fibroblast growth factor is bound, an MAPK signal pathway is initiated by FGFR3. Furthermore, the MAPK pathway can now relay the extracellular signal to trigger an intracellular response. The intracellular response provided by MAPK,…

position of the inositol resulting in phosphatidylinositol 3,4,5-triphosphate (PIP3). PIP3 triggers the activation of AKT/PKB signal pathway. AKT is a protooncogene protein that inhibits programmed cell death through binding of BAX preventing it from degrading the mitochondrial membrane that result in caspase-induced apoptosis. Furthermore, activation of AKT pathway signals Rheb that triggers mTOR activation translation factor S6K, which binds to the large ribosome subunit and promotes RNA…

The mitogen-activated protein kinase, or MAPK, pathway is a chain of proteins in the cell that relays an extracellular signal from the Ras protein to the DNA in the nucleus of the cell. This pathway consists of multiple phosphorylations as MAPKKK phosphorylates and activates MAPKK which then phosphorylates and activates MAPK. At the end of this cascade, MAPK phosphorylates various effector proteins (Alberts, 557). This signaling pathway plays an important role in cells as it results in complex…

Idiopathic pulmonary fibrosis (IPF) – the most common form of idiopathic interstitial pneumonia – is a chronic, progressive fibrotic lung disease that affects older adults. IPF is characterized by a continuing decline in lung function, poor survival, and limited therapeutic options. The invasive proliferation of fibrous tissue and scarring of the interstitium lead to a decline in forced vital capacity (FVC) (Richeldi et al. 2014). IPF has a poor prognosis; the median survival for the disease is…

The multifunctional protein, beta-catenin (CTNNB1) acts on many critical roles in the cell life cycle, including cell differentiation, proliferation and cell-cell contact (Ozwan et al., 1989), CTNNB1 plays a central role in canonical WNT signaling pathway to success the gene transcription process (Clevers and Nusse., 2012). Regulation and degradation of CTNNB1 take place at the cellular level through phosphorylation of serine and/or threonine amino acid residues. Specific kinase proteins…

Pathophysiology: Proteus syndrome is caused by an activating somatic mosaic mutation in AKT1, a gene which encodes the well-studied serine/threonine kinase PKB/Akt .1,2 Akt is the key mediator of the PI3K signaling pathway. In response to a growth signal (e.g. IGF, EGF) and the autophosphorylation of a receptor tyrosine kinase, PI3K is recruited and activated, generating PIP¬3 molecules at the lipid membrane. These partially activate Akt and also activate PDK1/2, which complete the Akt…

INTRODUCTION Ca2+ as an intracellular second messenger is indispensable for the physiology of organisms and the molecular regulation of cells. The cytosolic free Ca2+ concentration is a crucial signal for a variety of neuronal processes including neurotransmitter release, control of membrane excitability, synaptic plasticity, and cognition. Ca2+ homeostasis in neurons is accurate controlled by several types of Ca2+ channels or the activity of Ca2+ transporters with either locate on the plasma…

1.7 III (b) VEGF: VEGF is also known as vascular permeability factor (VPF) is an endothelial cell specific mitogen in in vitro and is the main factor responsible for vasculogenesis and angiogenesis in a variety of in vivo models. The gene transcripts level of VEGF is stimulated at the time of implantation because process of implantation occurs under hypoxic condition. In rodents, VEGF is involved during embryo–endometrium crosstalk by regulating endothelial cell proliferation and vascular…

Topic: Molecular mechanism of dietary restriction in ageing Title: Dietary restriction and mTOR signalling pathway in lifespan extension Dietary restriction (DR), which is reduced intake of all dietary constituents except vitamins and minerals, was first shown to extend the lifespan of rats 80 years ago (McCay, 1930). Since then, many studies have proven that DR can extend longevity on wide range of taxa (Fontana et al., 2010). In addition, research done on animal models reveals that there…