β-Adrenergic-induced cytosolic redistribution of Rap1 in rat parotid acini: role in secretion

1998 ◽  
Vol 274 (6) ◽  
pp. C1667-C1673 ◽  
Author(s):  
Nisha J. D’Silva ◽  
Kerry L. Jacobson ◽  
Sabrina M. Ott ◽  
Eileen L. Watson
Keyword(s):  
Muscarinic Agonist ◽  
Dependent Manner ◽  
Adrenergic Agonist ◽  
Amylase Release ◽  
Adrenergic Antagonist ◽  
Granule Membrane ◽  
Rat Parotid ◽  
A Site ◽  
The Relationship

Rap1 has recently been identified on the secretory granule membrane and plasma membrane of rat parotid acinar cells (N. J. D’Silva, D. DiJulio, C. B. Belton, K. L. Jacobson, and E. L. Watson. J. Histochem. Cytochem. 45: 965–973, 1997). In the present study, we examined the cellular redistribution of Rap1 following treatment of acini with isoproterenol (ISO), the β-adrenergic agonist, and determined the relationship between translocation and amylase release. In the presence of ISO, Rap1 translocated to the cytosol in a concentration- and time-dependent manner; this effect was not mimicked by the muscarinic agonist, carbachol. Translocation was maximal at 1 μM ISO and paralleled amylase release immediately after ISO stimulation. Rap1 translocation and amylase release were blocked by the β-adrenergic antagonist, propranolol, whereas okadaic acid, a downstream secretory inhibitor, significantly blocked amylase release but did not inhibit Rap1 redistribution. Results suggest that the translocation of Rap1 is causally related to secretion and that the role of Rap1 in secretion is at a site proximal to the exocytotic event.

Regulated phosphorylation of secretory granule membrane proteins of the rat parotid gland

1990 ◽  
Vol 259 (1) ◽  
pp. G70-G77 ◽  
Author(s):  
C. R. Marino ◽  
J. D. Castle ◽  
F. S. Gorelick
Keyword(s):  
Membrane Proteins ◽  
Parotid Gland ◽  
Secretory Granule ◽  
Integral Membrane Proteins ◽  
Dependent Manner ◽  
Amylase Release ◽  
Rat Parotid Gland ◽  
Granule Membrane ◽  
Rat Parotid ◽  
Granule Membrane Proteins

An antiserum raised against purified rat parotid secretory granule membrane proteins has been used to identify organelle-specific protein phosphorylation events following stimulation of intact cells from the rat parotid gland. After lobules were prelabeled with [32P]orthophosphate and exposed to secretagogues, phosphoproteins were immunoprecipitated with the granule membrane protein antiserum, separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and visualized by autoradiography. Parallel studies of stimulated amylase release were performed. Isoproterenol treatment of parotid lobules resulted in an increase in the phosphate content of immunoprecipitable 60- and 72-kDa proteins that correlated with amylase release in a time-dependent manner. Forskolin addition mimicked these effects, but only the isoproterenol effects were reversed by propranolol treatment. To confirm the specificity of the antiserum to the secretory granule membrane fraction, subcellular isolation techniques were employed following in situ phosphorylation. The 60- and 72-kDa phosphoproteins were immunoprecipitated from both a particulate fraction and a purified secretory granule fraction. Furthermore, the extraction properties of both species suggest that they are integral membrane proteins. These findings support the possibility that stimulus-regulated secretion may involve phosphorylation of integral membrane proteins of the exocrine secretory granule.

scholarly journals The relationship between intracellular Ca2+ concentration and adrenergic agonist-induced amylase release in rat parotid acini

1990 ◽  
Vol 52 ◽  
pp. 298
Author(s):  
Hiroko Nomura ◽  
Rie Yokoyama ◽  
Kikuko Ukai ◽  
Yukihiko Nomura ◽  
Masaru Chihara ◽  
...  
Keyword(s):  
Adrenergic Agonist ◽  
Amylase Release ◽  
Rat Parotid ◽  
The Relationship

scholarly journals Role of Hypoxia-Mediated Autophagy in Tumor Cell Death and Survival

Cancers ◽  
2021 ◽  
Vol 13 (3) ◽  
pp. 533
Author(s):  
Rania F. Zaarour ◽  
Bilal Azakir ◽  
Edries Y. Hajam ◽  
Husam Nawafleh ◽  
Nagwa A. Zeinelabdin ◽  
...  
Keyword(s):  
Cell Death ◽  
Type I ◽  
Dependent Manner ◽  
Destruction Process ◽  
Tumor Cell Death ◽  
Complex Regulation ◽  
Cancer Immunotherapies ◽  
The Relationship ◽  
Shed Light

Programmed cell death or type I apoptosis has been extensively studied and its contribution to the pathogenesis of disease is well established. However, autophagy functions together with apoptosis to determine the overall fate of the cell. The cross talk between this active self-destruction process and apoptosis is quite complex and contradictory as well, but it is unquestionably decisive for cell survival or cell death. Autophagy can promote tumor suppression but also tumor growth by inducing cancer-cell development and proliferation. In this review, we will discuss how autophagy reprograms tumor cells in the context of tumor hypoxic stress. We will illustrate how autophagy acts as both a suppressor and a driver of tumorigenesis through tuning survival in a context dependent manner. We also shed light on the relationship between autophagy and immune response in this complex regulation. A better understanding of the autophagy mechanisms and pathways will undoubtedly ameliorate the design of therapeutics aimed at targeting autophagy for future cancer immunotherapies.

Ion transport mechanisms in rat parotid intralobular striated ducts

1994 ◽  
Vol 266 (6) ◽  
pp. C1594-C1602 ◽  
Author(s):  
M. Paulais ◽  
E. J. Cragoe ◽  
R. J. Turner
Keyword(s):  
Ion Transport ◽  
Channel Blocker ◽  
K Channel ◽  
Muscarinic Agonist ◽  
Transport Mechanisms ◽  
Adrenergic Agonist ◽  
Acid Load ◽  
Rat Parotid ◽  
H Channels ◽  
Beta Adrenergic Agonist

The intracellular pH (pHi) indicator 2',7'-bis(carboxyethyl)-5(6)-carboxyfluorescein and microfluorimetry were used to characterize several ion transport mechanisms in rat parotid striated ducts. The recovery of ductal pHi from an acute acid load was Na+ dependent and inhibited by the amiloride analogue ethylisopropylamiloride with 50% inhibitory concentration 4.7 +/- 0.8 microM, indicating the presence of a Na(+)-H+ exchanger of the amiloride-insensitive type. The rate of this recovery was stimulated approximately 20% in ducts pretreated with the muscarinic agonist carbachol (10(-5) M) and inhibited approximately 20% in ducts pretreated with the beta-adrenergic agonist isoproterenol (10(-6) M). Upon removal of extracellular K+, ductal pHi rapidly decreased (0.19 +/- 0.02 pH units/min), consistent with a coupling between K+ and H+ (or OH-) fluxes in this tissue. In HCO(3-)-containing medium, the acidification due to K+ removal was blunted, arguing against ductal K(+)-HCO3- cotransport. However, the effect of K+ removal was inhibited by the K+ channel blocker Ba2+ (1 mM) and by the H+ channel blocker Zn2+ (25 microM), consistent with the involvement of electrically coupled K+ and H+ channels. The effect of K+ removal was unaffected by pretreatment of ducts with isoproterenol (10(-6) M) but markedly inhibited (approximately 50%) by pretreatment with carbachol (10(-5) M). No evidence for a significant component of Cl(-)-HCO3- exchange was found in striated ducts. The properties of the Na(+)-H+ exchanger and K(+)-H+ exchange mechanism identified here are consistent with their involvement in ductal salt reabsorption and secretion.

Social Practice, the Bodily Professions and the State

1990 ◽  
Vol 7 (1) ◽  
pp. 72-82 ◽  
Author(s):  
Robert Sparks
Keyword(s):  
Social Practice ◽  
English Language ◽  
The State ◽  
The Body ◽  
Modern State ◽  
Political Struggle ◽  
Sport Sociology ◽  
A Site ◽  
The Relationship

The relationship between sport and the modern state has been a focus of increased theoretical attention in recent years, particularly with respect to the role of sport in hegemony. At the same time there has been mounting interest in the significance of the body and bodily practices (including sports) as a site of political struggle. Yet, not much work has been done on the connection between these two projects. A monograph written in French and published in 1983 draws together many of these themes but has remained neglected in English-language sport sociology. This paper reviews Le corps programmé and discusses some of the book’s theoretical implications.

scholarly journals The role of calcium in the interaction of α- and β-adrenergic agonists on amylase release from rat parotid glands

1985 ◽  
Vol 39 ◽  
pp. 318
Author(s):  
Hiroko Nomura ◽  
Takahide Nomura ◽  
Hiroshi Maekawa ◽  
Ken Izuhara ◽  
Masakatsu Tachibana ◽  
...  
Keyword(s):  
Adrenergic Agonists ◽  
Parotid Glands ◽  
Amylase Release ◽  
Rat Parotid

scholarly journals CDPK6 phosphorylates and stabilizes MYB30 to promote hyperoside biosynthesis that prolongs the duration of full-blooming in okra

2020 ◽  
Vol 71 (14) ◽  
pp. 4042-4056
Author(s):  
Qing Yang ◽  
Biying Dong ◽  
Litao Wang ◽  
Zhihua Song ◽  
Lili Niu ◽  
...  
Keyword(s):  
Ectopic Expression ◽  
Fold Increase ◽  
Bimolecular Fluorescence Complementation ◽  
Dependent Manner ◽  
Flavonoid Pathway ◽  
Calcium Dependent ◽  
Key Enzyme ◽  
Dependent Protein ◽  
The Relationship

Abstract The flowers of okra (Abelmoschus esculentus) open and wilt within only a few hours, and this is accompanied by accumulation of hyperoside, a secondary metabolite in the flavonoid pathway. However, little is known about the relationship between flavonoids and flowering. Here, we found that exogenous application of hyperoside extended the duration of the full-blooming period by more than 3-fold, and this was accompanied by a 14.7-fold increase in the expression of CALCIUM-DEPENDENT PROTEIN KINASE6 (AeCDPK6). Gene expression profiling indicated that the transcription factor AeMYB30 was co-expressed with AeCDPK6, and detailed protein interaction and phosphorylation experiments together with yeast two-hybrid and bimolecular fluorescence complementation assays demonstrated an interaction between AeMYB30 and AeCDPK6. AeCDPK6 specifically phosphorylated AeMYB30S191, leading to increased protein stability and prevention of degradation. Furthermore, AeMYB30 directly bound to the promoter of AeUF3GaT1, a key enzyme in the hyperoside biosynthesis pathway. Analysis of transgenic plants showed that AeCDPK6 was required for the hyperoside-induced phosphorylation of AeMYB30 to enhance its stability and transcriptional activity. Ectopic expression of AeCDPK6 promoted hyperoside accumulation and prolonged the full-blooming period in an AeMYB30-dependent manner. Our results indicate the role of AeCDPK6–AeMYB30 in the molecular mechanism by which hyperoside regulates the period of full blooming in okra, a plant with a short duration of flowering.

Research and selection of rational parameters of a refrigerated container terminal

Innotrans ◽  
2021 ◽  
pp. 32-38
Author(s):  
Nazirjhon M. Aripov ◽  
◽  
Daurenbek I. Ilesaliev ◽  
Jamshid R. Kobulov ◽  
Shahboz R. Abduvahitov ◽  
...  
Keyword(s):  
Mutual Influence ◽  
Container Terminal ◽  
Technological Support ◽  
System A ◽  
Parametric Description ◽  
A Site ◽  
The Relationship ◽  
Selection Of

The article considers the role of transport and refrigerated warehouse complexes in continuous refrigerating supply chains (CRSCs). A summary diagram of technical and technological support is formed, describing the relationship and mutual influence of the elements of the CRSC system. A structural and parametric description of a refrigerated container terminal is carried out. The classification of the parameters of a refrigerated container terminal according to various characteristics is developed. The relationships between the parameters of a refrigerated container terminal are presented in the form of mathematical models. The dependence of the capacity of a refrigerated container terminal with respect to the length of a site is obtained.

Ezrin has properties to self-associate at the plasma membrane

1994 ◽  
Vol 107 (9) ◽  
pp. 2509-2521 ◽  
Author(s):  
C. Andreoli ◽  
M. Martin ◽  
R. Le Borgne ◽  
H. Reggio ◽  
P. Mangeat
Keyword(s):  
Plasma Membrane ◽  
Recombinant Baculovirus ◽  
Dependent Manner ◽  
Physiological Properties ◽  
Self Association ◽  
A Site ◽  
Apical Membranes ◽  
Gastric Parietal Cells ◽  
Overlay Assay

Ezrin, a member of a family of proteins involved in the interaction of the microfilament cytoskeleton with the plasma membrane, plays a role in membrane translocation in gastric parietal cells (Hanzel, D., Reggio, H., Bretscher, A., Forte, J. G. and Mangeat, P. (1991). EMBO J. 10, 2363–2373). Human ezrin was expressed in and purified from Escherichia coli. It possesses all the major biophysical, immunological and physiological properties of natural ezrin. Upon microinjection in live gastric HGT-1 cells, ezrin was incorporated into the dorsal microvilli, a site where the endogeneous protein is localized. By coimmunoprecipitation and ezrin-affinity assays, two HGT-1 cell proteins of 77 and 72 kDa behaved as ezrin-binding proteins. In enriched gastric apical membranes, 125I-ezrin labelled proteins of 80, 77 and 72 kDa by overlay assay. The 80 kDa protein was identified as ezrin and the 77 and 72 kDa proteins as gastric forms of proteins structurally related to ezrin, such as radixin and moesin. In insect cells infected with a recombinant baculovirus, one-third of over-expressed ezrin accumulated at the plasma membrane. Ezrin bound a 77 kDa endogenous peripheral membrane protein, behaving as an insect counterpart of the mammalian ezrin family. In addition to the respective role of the amino- and carboxyl-terminal domains of ezrin in linking the membrane and the cytoskeleton (Algrain, M., Turunen, O., Vaheri, A., Louvard, D. and Arpin, M. (1993). J. Cell Biol. 120, 129–139), both domains interacted synergistically in a salt-dependent manner to trigger self-association of ezrin. Ezrin's self-association properties could represent another way of regulating the number of ezrin molecules bound at specific membrane sites.

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