• Variation among these transcripts impacts their functions which involve roles in the calcium storage and release process in the endoplasmic and sarcoplasmic reticulum as well as hydroxylation of aspartic acid and asparagine in epidermal growth factor-like domains of various proteins. (wikipedia.org)
  • The sarcoplasmic reticulum (smooth endoplasmic reticulum) stores calcium, which is released into the sarcoplasm during muscle contraction. (medscape.com)
  • RyRs are expressed in the membrane of the sarcoplasmic (SR)/endoplasmic reticulum and are expressed in many tissues, with RyR1 and RyR2 being the predominant isoforms in skeletal and cardiac muscle respectively. (tocris.com)
  • PLN interacts with sarco/endoplasmic reticulum Ca 2+ -ATPase (SERCA) and regulates calcium uptake, which is modulated by the protein kinase A (PKA)-dependent phosphorylation of PLN during the fight-or-flight response. (elifesciences.org)
  • Glycogen storage disease type 1b is a metabolic disorder resulting in an inability to shuttle glucose-6-phosphate across the sarcoplasmic/endoplasmic reticulum (SR/ER) lumen. (endocrine-abstracts.org)
  • Ryanodine receptors (RyRs), located in the sarcoplasmic/endoplasmic reticulum (SR/ER) membrane, are necessary for intracellular Ca2+ launch that is involved with an array of cellular features. (abt-888.net)
  • Alongside the plasma membrane Ca 2+ -ATPase ( PMCA ) and sarcoplasmic/endoplasmic reticulum Ca 2+ -ATPase ( SERCA ), as well as the sodium/potassium/calcium exchangers (NKCX, SLC24 family ), NCX allow recovery of intracellular calcium back to basal levels after cellular stimulation. (guidetopharmacology.org)
  • Both extracellular and intracellular calcium concentrations are tightly regulated by bidirectional calcium transport across the plasma membrane of cells and intracellular organelles, such as the endoplasmic reticulum, the sarcoplasmic reticulum of muscle cells, and the mitochondria. (msdmanuals.com)
  • ATP2A2, located on 12q23-24.1, encodes the sarcoplasmic/endoplasmic reticulum Ca 2+ -ATP isoform 2 protein (SERCA2), which is a calcium pump. (medscape.com)
  • [ 1 ] This pump maintains a low cytoplasmic Ca 2+ level by actively transporting calcium ions from the cytosol into the lumen of the endoplasmic reticulum. (medscape.com)
  • In a different study, in which researchers systematically analyzed mutations identical to those found in patients with Darier disease, mutant SERCA2 protein aggregates were found to cause stress to the endoplasmic reticulum, subsequently inducing cell apoptosis. (medscape.com)
  • Each fiber is covered by a sarcolemma (plasma membrane). (medscape.com)
  • MARV assembles and buds from the host cell plasma where MARV matrix protein (mVP40) dimers associate with anionic lipids at the plasma membrane inner leaflet and undergo a dynamic and extensive self-oligomerization into the structural matrix layer. (uci.edu)
  • each fiber has a limiting plasma membrane, the sarcolemma. (wheelessonline.com)
  • The model considers three intracellular compartments, the cytosol, the sarcoplasmic reticulum, and microdomains beneath the plasma membrane. (cellml.org)
  • Normally, vasodilatation within these arteries occurs through activation of large-conductance, calcium-activated potassium channels on the plasma membrane by nearby localised calcium-release events - referred to calcium sparks - from the sarcoplasmic reticulum (SR) of vascular smooth muscle cells. (hospitalhealthcare.com)
  • When examined in cross-section, a typical muscle cell reveals between 4 and 6 nuclei, which lie just underneath the plasma membrane of the muscle fiber, the sarcolemma. (medscape.com)
  • There exists an exchange of molecules and ions in and out of the cell wall, as well as in and out of membrane-bounded intracellular compartments such as the nucleus, ER, and mitrochondria. (wikibooks.org)
  • ROS may induce intracellular calcium increase and subsequent contraction of PASMCs via direct or indirect interactions with protein kinases, phospholipases, sarcoplasmic calcium channels, transient receptor potential channels, voltage-dependent potassium channels and L-type calcium channels, whose relevance may vary under different experimental conditions. (ersjournals.com)
  • Junctophilin-2 (JPH2), a protein expressed in the junctional membrane complex, is necessary for proper intracellular calcium (Ca(2+)) signaling in cardiac myocytes. (duke.edu)
  • Excitable tissues rely on junctional membrane complexes to couple cell surface signals to intracellular channels. (duke.edu)
  • Exercise promotes the formation of intracellular junctions in skeletal muscle between stacks of sarcoplasmic reticulum (SR) cisternae and extensions of transverse-tubules (TT) that increase co-localization of proteins required for store-operated Ca 2+ entry (SOCE). (elifesciences.org)
  • The physiologic basis of flaccid weakness is inexcitability of the muscle membrane (ie, sarcolemma). (medscape.com)
  • The aim of the first study (Chapter Two) was to characterize changes in the kinetic properties of sarco(endo)-plasmic reticulum Ca2+-ATPase (SERCA) proteins in cardiac and skeletal muscles in response to b-adrenergic, Ca2+-dependent calmodulin kinase II (CaMKII) and protein kinase C (PKC) signaling. (uwaterloo.ca)
  • As part of the "flight or fight" response, protein kinase A phosphorylates phospholamban (PLN), thereby relieving a tonic inhibition of the endo/sarco-plasmic reticulum calcium pump, which results in an increased force of cardiac contraction. (elifesciences.org)
  • We predict this structure to be a membrane protein. (expasy.org)
  • Electron microscopy reveals loss of desmosomes (epithelial intercellular junctions formed by membrane and submembrane protein complexes), breakdown of desmosome-keratin intermediate filament attachment, and perinuclear aggregates of keratin intermediate filaments. (medscape.com)
  • Disrupted junctional membrane complexes and hyperactive ryanodine receptors after acute junctophilin knockdown in mice. (duke.edu)
  • This calcium moves the acetylcholine-containing miceles to fuse with the presynaptic membrane and release their acetylcholine into the synapse, where it is bound by acetylcholine receptors on the postsynaptic surface. (gsu.edu)
  • Ion channel dysfunction is usually well compensated with normal excitation, and additional triggers are often necessary to produce muscle inexcitability owing to sustained membrane depolarization. (medscape.com)
  • For example RyR1 is activated following membrane depolarization of skeletal muscle, whereas depolarization of cardiac muscle results in Ca 2+ influx through L-type Ca 2+ channels, which activates RyR2 by CICR. (tocris.com)
  • The action potential at one node is sufficient to excite a response at the next node, so the nerve signal can propagate faster by these discrete jumps than by the continuous propagation of depolarization/repolarization along the membrane. (gsu.edu)
  • The overall objective of this thesis was to examine mechanisms involved in the acute regulation of sarcoplasmic reticulum (SR) Ca2+-handling properties by second messenger signaling pathways in skeletal and cardiac muscle. (uwaterloo.ca)
  • Objective -To determine whether an alteration in calcium regulation by skeletal muscle sarcoplasmic reticulum, similar to known defects that cause malignant hyperthermia (MH), could be identified in membrane vesicles isolated from the muscles of Thoroughbreds with recurrent exertional rhabdomyolysis (RER). (avma.org)
  • Skeletal muscle membrane vesicles, prepared by differential centrifugation of muscle tissue homogenates obtained from the horses, were characterized for sarcoplasmic reticulum (SR) activities, including the Ca 2+ release rate for the ryanodine receptor-Ca 2+ release channel, [ 3 H]ryanodine binding activities, and rate of SR Ca 2+ -ATPase activity and its activation by Ca 2+ . (avma.org)
  • Tropomodulins, cytoplasmic γ-actin, and small ankyrin 1.5 mechanically stabilize the sarcoplasmic reticulum and maintain myofibril alignment in skeletal muscle fibers. (rupress.org)
  • The lipid bilayer of cell membranes is impermeable to large and polar molecules but permeable to water molecules and other small uncharged molecules like O 2 and CO 2 . (wikibooks.org)
  • The availability of free energy is one of the factors that determine if a molecule will move across a membrane, the other being the permeability of the molecule in the lipid bilayer. (wikibooks.org)
  • Two membrane curvature-sensing molecules with opposite chemistries are targeted to distinct vesicle classes through direct interaction with different lipid environments. (rupress.org)
  • Excitation-contraction coupling in striated muscle requires proper communication of plasmalemmal voltage-activated Ca2+ channels and Ca2+ release channels on sarcoplasmic reticulum within junctional membrane complexes. (duke.edu)
  • Reduced junctional Na+/Ca2+-exchanger activity contributes to sarcoplasmic reticulum Ca2+ leak in junctophilin-2-deficient mice. (duke.edu)
  • Mutation of the SoLute Carrier 37a4 (slc37a4) or glucose-6-phosphate transporter (G6PT) gene responsible for the distribution of G-6-P across this membrane leads to, hypoglycemia, hepatic glycogen accumulation, hyperlipidemia, resulting in life-limiting outcomes including growth retardation and neutropeni. (endocrine-abstracts.org)
  • Incubation of electrically-paced ventricular myocytes with a membrane-permeant Ins(1,4,5) P 3 ester provoked the occurrence of spontaneous diastolic Ca 2+ transients with the same characteristics and sensitivity to 2-APB as the events stimulated by endothelin-1. (biologists.com)
  • Osmosis is the diffusion of water through a semi-permeable membrane. (wikibooks.org)
  • When the propagating action potential reaches the axon, it proceeds down that "transmission line" by successive excitation of segments of the axon membrane. (gsu.edu)
  • At those uncovered areas of the axon membrane, the ion exchange necessary for the production of an action potential can take place. (gsu.edu)
  • In her PhD studies she explored the complex nature of transverse (T-) tubule extensions of the surface membrane which conduct the surface electrical signal throughout the fibre cross-section. (edu.au)
  • Excitation-contraction (EC) coupling is broadly defined as the signal transduction process that links a surface membrane action potential to contraction. (edu.au)
  • Diffusion is the process by which molecules migrate over the cell membrane from areas of higher concentration to areas of lower concentration. (wikibooks.org)
  • So, ion pumps are required in the membranes of cell and sarcoplasmic reticulum to maintain the ion balance inside the cell. (scholarpedia.org)
  • The stimulus triggers an action potential in the cell membrane of the nerve cell, and that action potential provides the stimulus for a neighboring segment of the cell membrane. (gsu.edu)
  • POM121 and Sun1, but not the Nup107-160 complex, are required for fusion of the inner and outer nuclear membrane during nuclear pore assembly in interphase of the cell cycle. (rupress.org)
  • When ΔG is positive the transport is active, an input of energy is needed to move a molecule up a concentration gradient, contrary to ΔG being negative the transport is passive, which means that such molecules will pass through a membrane down their own gradient, simple diffusion. (wikibooks.org)
  • The tail-anchoring domain of Bfl1 and HCCS1 targets mitochondrial membrane permeability to induce apoptosis. (osu.edu)
  • For charged species, an electrical potential is generated by an unequal distribution of ion charges across the membrane because "like" charges will be repelled. (wikibooks.org)