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Query: EC:2.7.11.1 (
protein kinase
)
81,284
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Cycle-purified microtubule protein from mammalian brain incorporated [32P]Pi upon incubation with [gamma-32P]GTP under the conditions used to promote assembly. This phosphorylation also occurred in the same proteins when phosphorylated with [gamma-32P]ATP and was only slightly stimulated by cAMP. GTP was a much less effective substrate than ATP. The transfer of phosphoryl groups from [gamma-32P]GTP to endogenous proteins followed a linear time-course and was stimulated by low concentrations of ATP and, more efficiently, by ADP. These data are in agreement with the predictions derived from a mechanism of phosphorylation by which [gamma-32P]GTP does not act as a phosphoryl donor for the
protein kinase
activity but, instead, only as a repository of high group transfer potential phosphoryl groups used to make [gamma-32P]ATP, from contaminating ADP, by means of the
nucleoside diphosphate kinase
activity. Using 100 mM fluoride, which suppressed protein phosphorylation without inhibiting the
nucleoside diphosphate kinase
activity, formation of [gamma-32P]ATP was detected. Fluoride was also able to protect microtubules from a slow depolymerization which was found to occur during long-term incubation of microtubules. This indicates that the phosphorylation observed in the presence of GTP is sufficient to destabilize microtubules.
...
PMID:Mechanism of endogenous phosphorylation of microtubule proteins during GTP-induced microtubule assembly and implications for stability of the assembled structures. 379 Jun 18
Rat liver
nucleoside diphosphate kinase
(
NDPK
) and PC12 cell cytosol were used to determine whether
NDPK
could function as a
protein kinase
.
NDPK
was phosphorylated on its catalytic histidine using [gamma-32P]ATP, and the phosphorylated
NDPK
separated from [gamma-32P]ATP. The addition of phosphorylated
NDPK
to dialyzed PC12 cell cytosol resulted in the phosphorylation of a protein with a subunit molecular mass of about 120 kDa. This phosphorylation appeared to occur by a direct transfer of a phosphoryl group from the catalytic histidine of
NDPK
to a histidine on the 120-kDa protein. The 120-kDa protein was partially purified and shown by peptide sequencing to be ATP-citrate lyase. ATP-citrate lyase is the primary source of cytosolic acetyl-CoA.
NDPK
phosphorylated the histidine at the catalytic site of ATP-citrate lyase. This histidine can also be phosphorylated by ATP, and its phosphorylation is the first step in the conversion of citrate and CoA to oxaloacetate and acetyl-CoA by ATP-citrate lyase. The level of phosphorylation of PC12 cell ATP-citrate lyase by phosphorylated
NDPK
was comparable with that by ATP. Thus, in addition to its
nucleoside diphosphate kinase
activity,
NDPK
can function as a
protein kinase
.
...
PMID:Phosphorylation of ATP-citrate lyase by nucleoside diphosphate kinase. 766 95
The effects of retinoic acid on components of the cAMP-dependent signalling system were examined in two related human neuroblastoma cell lines SK-N-SH-F (SHF) and SK-N-SH-N (SHN). Retinoid treatment for a week significantly increased the concentration of intracellular cAMP and the levels of activity of
protein kinase A
and adenylate cyclase in both cell lines. Retinoic acid treatment also caused a very marked translocation of
nucleoside diphosphate kinase
from the cytosol to the membrane fraction. The increases in cyclic nucleotide and
protein kinase A
activity were observed to occur as early as within 1 and 2 days respectively and preceded or were concurrent with the onset of observable morphological differentiation. Results also indicated that agents which elevated intracellular cAMP caused neuronal differentiation and blunted retinoic acid-induced melanocytic differentiation in SHF cells. However, increases in cAMP brought about by treatment of SHF cells with retinoic acid alone were several-fold smaller and thus insufficient to induce neuritogenesis in these cells. The results as a whole indicate that one overall effect of retinoic acid treatment is to upgrade the activity of components of the cAMP-dependent signalling system in both neuroblastoma cell lines. However, retinoic acid causes the SH-F and SH-N cell lines to differentiate along different routes which means that the upgrading responses may be related to more general aspects of differentiation rather than to specific phenotype expression.
...
PMID:Effect of retinoic acid on Nm/23 nucleoside diphosphate kinase and components of cyclic adenosine monophosphate-dependent signalling in human neuroblastoma cell lines. 774 87
Cyclic AMP affinity chromatography applied to various mammalian tissue extracts yielded two proteins in addition to the regulatory subunits of
protein kinase
. This paper characterizes these proteins and provides a simple procedure for their preparation. The polypeptides (36 kDa and a 19 kDa/21 kDa doublet) were isolated from the cAMP matrix by sequential elution with cAMP solutions of increasing concentrations. Microsequencing was accomplished following chemical or enzymic degradation of isolated polypeptides. Partial amino acid sequences of the 36 kDa protein and analyses of its enzymic activity indicated identity with glyceraldehyde-3-phosphate dehydrogenase whilst the lower MW protein proved to be identical with mammalian
nucleoside diphosphate kinase
subunits. In both cases, binding to cAMP appeared to occur at the nucleotide (NAD and ATP, respectively) sites. In conclusion, we present a one step-procedure, applicable to tissue and cell extracts, which allows the simultaneous isolation of both glyceraldehyde-3-phosphate dehydrogenase and
nucleoside diphosphate kinase
. This procedure may help to elucidate the multiple functions of these two important enzymes.
...
PMID:Isolation of the myc transcription factor nucleoside diphosphate kinase and the multifunctional enzyme glyceraldehyde-3-phosphate dehydrogenase by cAMP affinity chromatography. 776 89
We have investigated phosphorylation of human
nucleoside diphosphate kinase
(
NDPK
) and of homologous
NDPK
from different species by human
casein kinase 2
(
CK-2
). The human
NDPK
isotypes A and B were phosphorylated by
CK-2
in vitro both when the purified proteins and total lysate of HL-60 leukemia cells were used. The homologous
NDPK
's from Yeast and E. coli were also substrates for
CK-2
in vitro, but not Drosophila
NDPK
. Phosphorylation of all
NDPK
types by the
CK-2
holoenzyme was entirely polyamine-dependent. The
CK-2
phosphorylation site in human
NDPK
A, that was about 2.5 times stronger phosphorylated than was the B isotype, was tentatively assigned to Ser-122. The location of the corresponding residue in the 3D-structure of the 80% homologous Drosophila
NDPK
suggests that its phosphorylation may directly influence substrate binding and/or catalysis.
...
PMID:Phosphorylation of nm23/nucleoside diphosphate kinase by casein kinase 2 in vitro. 813 77
Two human nm23 genes have been identified, designated nm23-H1 and
nm23-H2
, which encode the 88% identical nucleoside-diphosphate kinase (NDPK) A and NDPK B polypeptides, respectively. The nm23-H1 gene product has been shown to play a functional role in the suppression of tumor metastasis. The Nm23 proteins/NDPK are highly conserved throughout evolution and are implicated in controlling cellular differentiation and development in various species, while the underlying mechanisms remain undefined. Neither the NDPK activity nor the DNA-binding activity, identified recently for NDPK B, can satisfactory explain the regulatory functions of Nm23. The present study provides evidence that purified Nm23 proteins are capable of transferring a phosphate group to other proteins when non-denaturing amounts of urea are present. This novel Nm23/NDPK activity was found to be specific for serine and threonine residues, and the transphosphorylation of substrate proteins occurred stoichiometrically. Because of the absence of a substrate turn-over, the novel function was termed protein phosphotransferase activity instead of
protein kinase
activity. It is demonstrated that urea stimulates the interaction of NDPK with other proteins. Identical phosphoprotein patterns were obtained using purified NDPK preparations from human, Drosophila, yeast and Dictyostelium in the presence of urea. Partially purified NDPK from human erythrocytes produced a similar phosphorylation pattern independent of urea addition and also acted stoichiometrically. In this preparation, a protein phosphotransferase activity of Nm23 species may possibly be generated and/or stabilized by the interaction with copurified proteins. Using different mutants of Dictyostelium NDPK it was shown that the protein phosphotransferase activity depends on the same active site as the NDPK activity. A phosphotransfer mechanism analogous to that of protein-histidine kinases is proposed, involving a high-energy phosphohistidine intermediate. Furthermore, the novel Nm23 function is compared with an apparently similar protein phosphotransferase activity which was observed previously with partially purified NDPK from different plant species.
...
PMID:A novel serine/threonine-specific protein phosphotransferase activity of Nm23/nucleoside-diphosphate kinase. 852 41
Although a number of nucleoside diphosphate kinases (NDPKs) have been reported to act as inhibitors of metastasis or as a transcription factor in mammals, it is not known whether these functions are linked to their enzymatic activity or how this protein is regulated. In this report, we show that in vitro
protein kinase CK2
catalyzed phosphorylation of human
NDPK
A inhibits its enzymatic activity by inhibiting the first step of its ping-pong mechanism of catalysis: its autophosphorylation. Upon in vivo 32P labeling of HeLa cells, we observed that both human NDPKs, A and B, were autophosphorylated on histidine residues, however, only the B isoform appeared to be serine phosphorylated.
...
PMID:Inhibition of nucleoside diphosphate kinase activity by in vitro phosphorylation by protein kinase CK2. Differential phosphorylation of NDP kinases in HeLa cells in culture. 898 Jan 48
We have previously shown that nucleotide species (adenosine triphosphate [ATP] or guanosine triphosphate [GTP]), [Cl-], and anion species determine the steady-state phosphorylation of apical membrane proteins within human airway epithelium in vitro. We found that a Cl(-)-regulated 37-kD protein (p37) principally phosphorylated with GTP but not ATP as substrate. Here we show that apical membranes from sheep tracheal epithelium also contain a Cl(-)-regulated 37-kD phosphoprotein (p37s) and characterize one of the kinases involved in the regulation of p37s. Analysis of phosphorylation of apical membrane proteins with gamma[32P]GTP in the presence of MgCl2 showed that two proteins circa 19 and 21 kD (p19s and p21s) were transiently phosphorylated before p37s. Renaturation of apical membrane proteins within polyacrylamide gels showed that p19s and p21s autophosphorylated with either gamma[32P]GTP or gamma[32P]ATP as substrates, suggesting that the two proteins were kinases. Immunoblotting and immunoprecipitation with a specific polyclonal antibody showed that p21s was a membrane-bound isoform of
nucleoside diphosphate kinase
(NDPK, EC 2.7.4.6), a
protein kinase
which catalyzes transfer of terminal phosphate from ATP to diphosphate nucleotides and is, among other functions, essential for cell secretion. Incubation of apical membrane proteins in the presence of gamma[32P]ATP and guanosine diphosphate (GDP) (but not GDPbetaS) resulted in enhancement of phosphorylation of p37s. Dephosphorylation of NDPK was stimulated by the addition of Mg2+, Mn2+, and Co2+ (but not Zn2+ or Ca2+). Our data show that ovine trachea is a good model for further characterization of the chloride-dependent cascade in airway epithelium.
...
PMID:Nucleoside diphosphate kinase and Cl(-)-sensitive protein phosphorylation in apical membranes from ovine airway epithelium. 947 15
We have previously reported that phosphorylation of a 15-kDa protein increased after blue-light irradiation in Neurospora crassa. In this study, the 15-kDa protein was purified using four columns; DEAE-cellulose, Blue-Sepharose, SP-Sepharose and Mono Q. The 15-kDa protein was shown to be homologous with
nucleoside diphosphate kinase
by amino acid sequencing and was also shown to possess
nucleoside diphosphate kinase
activity. A gene encoding N. crassa
nucleoside diphosphate kinase
, ndk-1, was isolated from the mycelial cDNA and genomic libraries. The deduced amino acid sequence of NDK-1 was identical to that of the 15-kDa protein. Northern blot analysis suggested that WC-1 and WC-2, the key factors of blue-light signal transduction in N. crassa, did not regulate NDK-1 at the transcriptional level. NDK-1 also showed rapid autophosphorylation activity and
protein kinase
activity against myelin basic protein with a Km value of 0.36 mM. These results suggest that NDK-1 acts as a signal transducer by phosphorylating proteins.
...
PMID:Isolation and characterization of Neurospora crassa nucleoside diphosphate kinase NDK-1. 1058 64
In Neurospora crassa, the phosphorylation of
nucleoside diphosphate kinase
(
NDK
)-1 is rapidly enhanced after blue light irradiation. We have investigated the function of
NDK
-1 in the blue light signal transduction pathway. A mutant called psp (phosphorylation of small protein) shows undetectable phosphorylation of
NDK
-1 and is defective in light-responsive regulation of perithecial polarity. Sequencing analysis of ndk-1 cDNA by reverse transcription-polymerase chain reaction revealed that proline 72 of ndk-1 was replaced with histidine in psp. The mutation ndk-1(P72H) resulted in accumulation of normal levels of mRNA and of about 25% of
NDK
-1(P72H) protein compared with that of wild type as determined by Western blot analysis. The ectopic expression of cDNA and introduction of genomic DNA of wild type ndk-1 in psp (ndk-1(P72H)) suppressed the reduction in accumulation and phosphorylation of
NDK
-1 and the light-insensitive phenotype. These findings demonstrated that the phenotype of psp was caused by the ndk-1(P72H) mutation. Biochemical analysis using recombinant
NDK
-1 and
NDK
-1(P72H) indicated that the P72H substitution in
NDK
-1 was responsible for the decrease in phosphotransfer activities, 5% of autophosphorylation activity, and 2% of V(max) for
protein kinase
activity phosphorylating myelin basic protein, compared with those of wild type
NDK
-1, respectively.
...
PMID:A point mutation in nucleoside diphosphate kinase results in a deficient light response for perithecial polarity in Neurospora crassa. 1128 15
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