| Interacting proteins: Q99418 and P84077 |
Pubmed |
SVM Score :0.0 |
| We recently have identified a human protein , ARNO ( ARF nucleotide binding site opener ) , as an ARF 1 GEF that shares a conserved domain with the yeast Sec 7 protein . ^^^ |
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| Interacting proteins: Q99418 and P84077 |
Pubmed |
SVM Score :0.0 |
| Here we characterized a smaller human protein ( relative molecular mass 47K ) named ARNO , which contains a central Sec 7 domain that promotes guanine nucleotide exchange on ARF 1 . ^^^ The exchange activity of ARNO is not inhibited by brefeldin A , an agent known to block vesicular transport and inhibit the exchange activity on ARF 1 in cell extracts . ^^^ |
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| Interacting proteins: Q99418 and P84077 |
Pubmed |
SVM Score :0.0 |
| Arno is a 47 kDa human protein recently identified as a guanine nucleotide exchange factor for ADP ribosylation factor 1 ( ARF 1 ) with a central Sec 7 domain responsible for the exchange activity and a carboxyl terminal pleckstrin homology ( PH ) domain ( Chardin , P . , Paris , S . , Antonny , B . , Robineau , S . , Braud Dufour , S . , Jackson , C . ^^^ Role of protein phospholipid interactions in the activation of ARF 1 by the guanine nucleotide exchange factor Arno . ^^^ Binding of the PH domain to phosphatidylinositol 4 , 5 bisphosphate ( PIP 2 ) greatly enhances Arno mediated activation of myristoylated ARF 1 . ^^^ We show here that in the absence of phospholipids , Arno promotes nucleotide exchange on [ Delta 17 ] ARF 1 , a soluble mutant of ARF 1 lacking the first 17 amino acids . ^^^ Arno catalyzes the release of GDP more efficiently than that of GTP from [ Delta 17 ] ARF 1 , and a stable complex between Arno Sec 7 domain and nucleotide free [ Delta 17 ] ARF 1 can be isolated . ^^^ |
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| Interacting proteins: Q99418 and P84077 |
Pubmed |
SVM Score :0.0 |
| Furthermore , the loading of permeabilized strips with the combination of the recombinant fully myristoylated ARF 1 , the guanine nucleotide exchange factor ARNO , and guanosine 5 ' triphosphate did not change the tone at constant pCa ( 6 . 45 ) and did not modify the carbachol and guanosine 5 ' O ( 3 thiotriphosphate ) induced Ca2+ sensitization . ^^^ |
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| Interacting proteins: Q99418 and P84077 |
Pubmed |
SVM Score :0.0 |
| In HEK cell membranes , addition of purified recombinant ARNO , a guanine nucleotide exchange factor for ARF 1 . potentiated the GTP [ S ] stimulated PLD activity . ^^^ |
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| Interacting proteins: Q99418 and P84077 |
Pubmed |
SVM Score :0.0 |
| Recently , ARNO and its close homologue cytohesin 1 were found to catalyze in vitro nucleotide exchange on ARF 1 and ARF 3 , respectively , raising the possibility that these GEFs function in the Golgi . ^^^ We report here that in vitro ARNO can stimulate nucleotide exchange on both ARF 1 and ARF 6 . ^^^ |
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| Interacting proteins: Q99418 and P84077 |
Pubmed |
SVM Score :0.0 |
| Here we report the crystal structure of the catalytic Sec 7 homology domain of Arno , a human GEF for ARF 1 , determined at 2 . 2 angstroms resolution . ^^^ |
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| Interacting proteins: Q99418 and P84077 |
Pubmed |
SVM Score :0.0 |
| An exchange factor for human Arf 1 , ARNO , and two closely related proteins , named cytohesin 1 and GPS 1 , have been identified . ^^^ |
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| Interacting proteins: Q99418 and P84077 |
Pubmed |
SVM Score :0.0 |
| A glutamic finger in the guanine nucleotide exchange factor ARNO displaces Mg2+ and the beta phosphate to destabilize GDP on ARF 1 . ^^^ The Sec 7 domain of the guanine nucleotide exchange factor ARNO ( ARNO Sec 7 ) is responsible for the exchange activity on the small GTP binding protein ARF 1 . ^^^ ARNO Sec 7 forms a stable complex with the nucleotide free form of [ Delta 17 ] ARF 1 , a soluble truncated form of ARF 1 . ^^^ The crystal structure of ARNO Sec 7 has been solved recently , and a site directed mutagenesis approach identified a hydrophobic groove and an adjacent hydrophilic loop as the ARF 1 binding site . ^^^ We show that Glu 156 in the hydrophilic loop of ARNO Sec 7 is involved in the destabilization of Mg2+ and GDP from ARF 1 . ^^^ |
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| Interacting proteins: Q99418 and P84077 |
Pubmed |
SVM Score :0.0 |
| Overexpression of the ARF 1 exchange factor ARNO inhibits the early secretory pathway and causes the disassembly of the Golgi complex . ^^^ ARNO ( ARF nucleotide site opener ) has been shown to act in vitro as a GTP exchange factor for ARF 1 . ^^^ |
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| Interacting proteins: Q99418 and P84077 |
Pubmed |
SVM Score :0.0 |
| EFA 6 promotes efficient guanine nucleotide exchange on ARF 6 and is distinct from the ARNO family of ARF 1 exchange factors . ^^^ |
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| Interacting proteins: Q99418 and P84077 |
Pubmed |
SVM Score :0.0 |
| Two pairs of residues at positions 190 191 and 198 208 ( Arno numbering ) in Sec7d contribute equally to the stability of BFA binding , which is also sensitive to mutation of H 80 in ARF 1 . ^^^ |
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| Interacting proteins: Q99418 and P84077 |
Pubmed |
SVM Score :0.0 |
| Catalytically inactive constructs of PLD 2 and RhoA , but not PLD 1 , ADP ribosylation factor 1 ( ARF 1 ) , ARF 6 , or ADP ribosylation factor nucleotide exchange factor ( ARNO ) blocked Ang 2 induced PLD activity in SHR and WKY PGSMCs . ^^^ |
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| Interacting proteins: Q99418 and P84077 |
Pubmed |
SVM Score :0.0 |
| We show here that an Arf nucleotide exchange factor , ARNO ( ADP ribosylation factor nucleotide site opener ) as well as Arf 6 and Arf 1 small GTPases are located in the kidney proximal tubule receptor mediated endocytosis pathway , and that ARNO and Arf 6 recruitment from cytosol to endosomes is pH dependent . ^^^ By Western blot analysis ARNO , Arf 6 , and Arf 1 were detected both in purified endosomes and in proximal tubule cytosol . ^^^ |
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| Interacting proteins: Q99418 and P84077 |
Pubmed |
SVM Score :0.0 |
| This transition requires ARNO catalytic activity , which we show leads to enhanced activation of endogenous ARF 6 , but not ARF 1 , using a novel pulldown assay . ^^^ |
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| Interacting proteins: Q99418 and P84077 |
Pubmed |
SVM Score :0.0 |
| In vitro , ARNO diglycine and cytohesin 1 triglycine enhanced phospholipase D 1 ( PLD 1 ) activation by Arf 1 with near maximal effects at 250 nM . ^^^ PLD activation was well correlated with GTP binding to Arf 1 , and cytohesin 1 was always more potent than ARNO in the PLD and GTP binding assays . ^^^ Increasing Mg2+ concentrations reduced PLD and Arf 1 activation by Arf GEFs . fMetLeuPhe and phorbol 12 myristate 13 acetate stimulated ARNO and cytohesin 1 as well as Arf 1 translocation to HL 60 cell membranes . fMetLeuPhe mediated ARNO recruitment , but not cytohesin 1 and Arf 1 translocation , was blocked by phosphatidylinositol 3 kinase inhibitors . ^^^ |
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| Interacting proteins: Q99418 and P84077 |
Pubmed |
SVM Score :0.0 |
| The proteins Arno and Gea 2 of the Sec 7 family can promote GDP GTP exchange on Arf 1 , a small GTP binding protein , which coordinates coated vesicle formation for protein transport within the cell . ^^^ Starting from a set of complementary crystal structures , we compared the collective movements of unbound Gea 2 and Arno Sec 7 domains , Arf 1 GDP , and the Arf 1 Gea2 ( Sec7d ) nucleotide free complex using normal modes analyses . ^^^ |
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| Interacting proteins: Q99418 and P84077 |
Pubmed |
SVM Score :0.0 |
| The three TRIO GEFD 1 inhibitors had no effect on ARHGEF 17 and ARNO [ ARF ( ADP ribosylation factor ) nucleotide binding site opener ] , two exchange factors for RhoA and Arf 1 respectively . ^^^ |
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| Interacting proteins: Q99418 and P84077 |
Pubmed |
SVM Score :0.0 |
| Molecular modeling of the analogues revealed that both the C 4 and C 7 derivatives were well tolerated at the interface between ARF 1 and its guanine nucleotide exchange factor ARNO . ^^^ |
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| Interacting proteins: Q99418 and P84077 |
Pubmed |
SVM Score :0.0 |
| NA |
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| Interacting proteins: Q99418 and P84077 |
Pubmed |
SVM Score :0.0 |
| NA |
|
| Interacting proteins: Q99418 and P84077 |
Pubmed |
SVM Score :0.0 |
| NA |
|
| Interacting proteins: Q99418 and P84077 |
Pubmed |
SVM Score :0.0 |
| NA |
|
| Interacting proteins: Q99418 and P84077 |
Pubmed |
SVM Score :0.0 |
| NA |
|
| Interacting proteins: Q99418 and P84077 |
Pubmed |
SVM Score :0.0 |
| NA |
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