Casein kinase 2: An ‘eminence grise’ in cellular regulation?

Pinna, Lorenzo A.

doi:10.1016/0167-4889(90)90098-x

Cited by 916 publications

(613 citation statements)

References 157 publications

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“…The cleavage point is between the amino acids alanine and isoleucine at positions 21/22. A presumed phosphorylation site at a serine residue is double-underlined [22]. The hydropathy plot, according to Kyte and Doolittle [ 17] (Fig.…”

Section: Characteristics Of the Ntm19 Proteinmentioning

confidence: 99%

Isolation and characterization of a microspore-specific gene from tobacco

et al. 1996

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The characterization of a gene with a unique microspore-specific expression pattern is reported. Isolated microspores from tobacco were used to synthesize a cDNA library. Clones that did not hybridize to leaf cDNA were further characterized by northern analysis. One clone proved to be a microspore-specific cDNA, representing a transcript of 650 nt. The corresponding gene, NTM19 (Nicotiana tabacum microspore-specific), was isolated and its sequence analysed. The gene encodes a protein of 10.8 kDa with a pI of 6.92 and a putative signal sequence at the N-terminus. A localization study revealed a unique spatial and temporal distribution. The transcript was only detected in the unicellular microspore. No hybridization signals were observed in other pollen developmental stages, nor in the surrounding anther tissues or other vegetative tissues of the plant. Therefore it can be concluded that NTM 19 is a gene with a highly microspore-specific character according to both localization and stage of expression. Southern blot analysis demonstrated the presence of a small gene family. The occurrence of TNM 19 was investigated in a range of closely and distantly related species and was found to be present in other solanaceous species, including the ancestors of tobacco and in a monocot species.

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Section: Characteristics Of the Ntm19 Proteinmentioning

confidence: 99%

Isolation and characterization of a microspore-specific gene from tobacco

et al. 1996

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“…Its ubiquity in eukaryotes and the very high conservation of its amino acid composition from yeast to man strongly suggests a vital role in cellular metabolism (for reviews: see Pinna, 1990;Tuazon and Traugh, 1991;Issinger, 1993;Allende and Allende, 1995). The enzyme has been shown to be elevated in rapidly growing cells (for review see: Issinger and Boldyre , 1992).…”

Section: Introductionmentioning

confidence: 99%

The carboxy terminus of p53 mimics the polylysine effect of protein kinase CK2-catalyzed MDM2 phosphorylation

Guerra¹,

Götz

Wagner

et al. 1997

Oncogene

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The oncogene product MDM2 can be phosphorylated by protein kinase CK2 in vitro 0.5 ± 1 mol of phosphate were incorporated per mol MDM2 protein. The catalytic subunit of protein kinase CK2 (a-subunit) catalyzed the incorporation of twice as much phosphate into the MDM2 protein as it was obtained with the holoenzyme. Polylysine stimulated MDM2 phosphorylation by CK2 holoenzyme threefold in contrast to the a-subunitcatalyzed MDM2 phosphorylation which was reduced by about 66% when polylysine was added. Full length p53, but also a peptide representing a C-terminal fragment of the tumor suppressor gene product p53 (amino acids 264 ± 393 which also harbors the CK2b interaction site at amino acids 287 ± 340) mimicked the polylysine e ect in all respects, ie. stimulation of phosphate incorporation by CK2 holoenzyme and inhibition in the presence of the catalytic CK2 a-subunit. Stimulation by p53 264 ± 393 was on the average close to twofold and inhibition in the case of the a-subunitcatalyzed MDM2 phosphorylation was about 40%. Phosphorylation of MDM2 by CK2 holoenzyme in the presence of the p21 WAF1/CIP1 , known to be a potent inhibitor of cyclin-dependent protein kinases, also led to a signi®cant reduction of phosphate incorporation into MDM2 indicating that p21 WAF1/CIP1 does not exclusively inhibit cell cycle kinases. Furthermore, these data add new insight into the autoregulatory loop which include p21 WAF1/CIP1 , MDM2 protein, CK2 and p53.

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“…The different effects of mutations on heparin and pseudosubstrate inhibition may reflect the observation that while the latter is a purely competitive inhibitor with respect to the phosphoacceptor substrate, the actual mode of heparin inhibition remains a matter of debate, as discussed in [1], where a number of arguments supporting the possibility that heparin might interact with site(s) partially distinct from the catalytic one are cited. Consistent with this interpretation would be also the finding that two CK2 mutants partially altered in the 74-77 basic quartet are not seriously defective in substrate recognition, despite their drastically reduced sensitivity to heparin [18,19].…”

Section: Resultsmentioning

confidence: 99%

“…1 shows the effect of increasing concentrations of heparin on the activity of CK2 wild type and five mutants in which basic residues have been variably replaced by alanines. All the assays were performed using the best known peptide substrate for CK2 [16] RRRADDSDDDDD, in which all the positions between -2 and +5, where acidic residues are known to act as positive determinants [1], are occupied by aspartic acid. While the inhibition of two mutants, K79R80K83A and R278K279R280A, is indistinguishable from that of CK2 wild type (ICs0 values around 0.1 ~g/ml) the other mutants display deeply altered heparin sensitivity.…”

Section: Methodsmentioning

confidence: 99%

“…This would imply the presence of complementary basic residues in the catalytic subunits. A crucial role of basic residues in CK2 is highlighted by other properties as well, notably its unusual site specificity, determined by rows of acidic residues mostly located down-stream from the target aminoacid [1] and its extreme sensitivity to polyanionic inhibitors, such as heparin [10] and the random polymers poly(Glu,Tyr)4:l [11]. In order to identify the structural elements responsible for these peculiar properties of CK2 we have started to mutate the conserved basic residues of human a-subunit that are divergent from the homologous residues in the majority of Ser/Thr protein kinases, which are basophilic instead of acidophilic like CK2.…”

Section: Introductionmentioning

confidence: 99%

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Mapping the residues of protein kinase CK2 α subunit responsible for responsiveness to polyanionic inhibitors

et al. 1996

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The quadruple mutation of the whole basic cluster, K74KKK 77 conserved in the catalytic subunits of protein kinase CK2 and implicated in substrate recognition, not only abolishes inhibition by heparin but even induces with some peptide substrates an up to 5-fold stimulation by heparin in the 0.5-5/tg/ml concentration range. Two other mutants defective in substrate recognition, R191,195K198A and K79R80K83A, display either a 100-fold reduction or no alteration at all in heparin inhibition, respectively. In contrast sensitivity to heparin inhibition is increased 30-fold by a single mutation affecting Arg-228 while it is not altered by a triple mutation in the small insert of subdomain XI (mutant R278K279R280A). The effect of the same mutations on inhibition by pseudosubstrate EEEEEYEEEEEEE is different, the mutant displaying the most reduced sensitivity being R191,195K198A, followed by K74-77A and K79R80K83A; the other mutants are almost indistinguishable from CK2 wild type. Substantial reduction of inhibition by poly(Glu,Tyr)4:l is only observable with mutant R191,195K198A, whereas R228A is significantly more sensitive to inhibition. These data show that the mode of inhibition of CK2 by polyanionic compounds occurs through substantially different mechanisms involving residues that are variably concerned with substrate recognition.

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Casein kinase 2: An ‘eminence grise’ in cellular regulation?

Cited by 916 publications

References 157 publications

Isolation and characterization of a microspore-specific gene from tobacco

Isolation and characterization of a microspore-specific gene from tobacco

The carboxy terminus of p53 mimics the polylysine effect of protein kinase CK2-catalyzed MDM2 phosphorylation

Mapping the residues of protein kinase CK2 α subunit responsible for responsiveness to polyanionic inhibitors

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