EurekaMag
+ Translate
+ Most Popular
The pigeon tick (Argas reflexus): its biology, ecology, and epidemiological aspects
Prevalence of hemoglobin abnormalities in Kebili (Tunisian South)
Lipogranuloma: a preventable complication of dacryocystorhinostomy
Value of basal plasma cortisol assays in the assessment of pituitary-adrenal insufficiency
Bees from the Belgian Congo. The acraensis group of Anthophora
Placing gingival retraction cord
Total serum IgE, allergy skin testing, and the radioallergosorbent test for the diagnosis of allergy in asthmatic children
Acariens plumicoles Analgesoidea parasites des oiseaux du Maroc
Injuries of terminal phalanges of the fingers in children
Biology of flowering and nectar production in pear (Pyrus communis)
Das Reliktvorkommen der Aspisviper (Vipera aspis L.) im Schwarzwald
Hydrological modelling of drained blanket peatland
Pathologic morphology and clinical significance of the anomalous origin of the left circumflex coronary artery from the right coronary artery. General review and autopsy analysis of 30 cases
Cyto genetic analyses of lymphocyte cultures after exposure to calcium cyclamate
Axelrodia riesei, a new characoid fish from Upper Rio Meta in Colombia With remarks concerning the genus Axelrodia and description of a similar, sympatric, Hyphessobrycon-species
Favorable evolution of a case of tuberculosis of pancreas under antibiotic action
RIFM fragrance ingredient safety assessment, Valencene, CAS Registry Number 4630-07-3
Parenteral microemulsions: an overview
Temperate pasture: management for grazing and conservation
Evaluation of a new coprocessed compound based on lactose and maize starch for tablet formulation
Thermal expansion and cracking of three confined water-saturated igneous rocks to 800C
Revision of the genera of the tribe Stigmoderini (Coleoptera: Buprestidae) a discussion of phylogenetic relationships
Anal tuberculosis. Report of a case
Gastric tuberculosis in the past and present
Adaptive responses of the cardiovascular system to prolonged spaceflight conditions: assessment with Holter monitoring

Phosphorylated carboxy terminal serine residues stabilize the mouse gap junction protein connexin45 against degradation


Phosphorylated carboxy terminal serine residues stabilize the mouse gap junction protein connexin45 against degradation



Journal of Membrane Biology 162(3): 247-257



ISSN/ISBN: 0022-2631

PMID: 9543497

DOI: 10.1007/s002329900362

Phosphoamino acid analysis of mouse connexin45 (Cx45) expressed in human HeLa cells revealed that phosphorylation occurred mainly at serine residues, but also on tyrosine and threonine residues. To characterize the role of Cx45 phosphorylation, different serine residues of the serine-rich carboxy terminal region were deleted or exchanged for other amino acids residues. Human HeLa cells deficient in gap junctional intercellular communication were stably transfected with appropriate constructs and analyzed for expression, localization, phosphorylation, formation of functional gap junction channels and degradation of mutant Cx45. After exchange or deletion of nine carboxy terminal serine residues, phosphorylation was decreased by 90%, indicating that these serine residues represented main phosphorylation sites of mouse Cx45. The various serine residues of this region contributed differently to the phosphorylation of Cx45 suggesting a cooperative mechanism for phosphorylation. Substitution of different serine residues for other amino acids did not interfere with correct intracellular trafficking and assembly of functional gap junction channels, as shown by localization of mutant Cx45 at the plasma membrane and by dye transfer to neighboring cells. Truncated Cx45 was also weakly phosphorylated but was trapped in perinuclear locations. Dye transfer of these transfectants was similar as in nontransfected HeLa cells. The half-life of mouse Cx45 protein in HeLa cells was determined as 4.2 hr. Pulse-chase experiments with the different transfectants revealed an increased turnover of Cx45, when one or both of the serine residues at positions 381 and 382 or 384 and 385 were exchanged for other amino acids. The half-life of these mutants was diminished by 50% compared to wild type Cx45.

Please choose payment method:






(PDF emailed within 0-6 h: $19.90)

Accession: 009188676

Download citation: RISBibTeXText

Related references

The gap-junction protein connexin 56 is phosphorylated in the intracellular loop and the carboxy-terminal region. European Journal of Biochemistry 244(1): 89-97, 1997

The gap-junction connexin 56 is phosphorylated in the intracellular loop and the carboxy-terminal region. European Journal of Biochemistry 244: 97, 1997

Functional analysis of carboxy terminal serine residues in connexin31 containing gap junction channels. European Journal of Cell Biology 72(Suppl. 43): 76, 1997

The Rift Valley fever virus nonstructural protein NSs is phosphorylated at serine residues located in casein kinase II consensus motifs in the carboxy-terminus. Virology 263(2): 517-525, 1999

The serine-rich Entamoeba histolytica protein is a phosphorylated membrane protein containing O-linked terminal N-acetylglucosamine residues. Journal of Biological Chemistry 270(8): 4121-4126, 1995

The serine-rich Entamoeba histolytica protein is a phosphorylated membrane protein containing OMICRON-linked terminal N-acetylglucosamine residues. Journal of Biological Chemistry 270.8 (February 24): 4121-4126, 1995

Carboxy-terminal residues of mouse thymidine kinase are essential for rapid degradation in quiescent cells. Journal of Molecular Biology 259(3): 383-392, 1996

Phosphorylated and non-phosphorylated connexin-32 molecules in gap junction plaques are protected against calpain proteolysis after phosphorylation by protein kinase C. Biochemical Society Transactions 22(3): 793-796, 1994

Identification of amino terminal and carboxyl terminal serine residues on the voltage sensitive sodium channel from electrophorus electricus phosphorylated by endogenous kinase. Society for Neuroscience Abstracts 16(1): 183, 1990

Exchange of serine residues 263 and 266 reduces the function of mouse gap junction protein connexin31 and exhibits a dominant-negative effect on the wild-type protein in HeLa cells. Experimental Cell Research 294(2): 446-457, 2004

Microtubule-assisted altered trafficking of astrocytic gap junction protein connexin 43 is associated with depletion of connexin 47 during mouse hepatitis virus infection. Journal of Biological Chemistry 292(36): 14747-14763, 2017

Conservation of a cytoplasmic carboxy-terminal domain of connexin 43, a gap junctional protein, in mammal heart and brain. Journal of Membrane Biology 115(3): 229-240, 1990

The phosphorylated ribosomal protein S7 in Tetrahymena is homologous with mammalian S4 and the phosphorylated residues are located in the C-terminal region. Structural characterization of proteins separated by two-dimensional polyacrylamide gel electrophoresis. Journal of Biological Chemistry 270(11): 6000-6005, 1995

Phosphoprotein phosphatase inhibitor-2 is phosphorylated at both serine and threonine residues in mouse diaphragm. Febs Letters 183(2): 423-429, 1985

The role of histidine residues on pH sensitivity of the gap junction protein connexin 43. Circulation 94(8 Suppl. ): I8, 1996