Faculty Opinions recommendation of Drosophila doubletime mutations which either shorten or lengthen the period of circadian rhythms decrease the protein kinase activity of casein kinase I.

ABSTRACT In both mammals and fruit flies, casein kinase I has been shown to regulate the circadian phosphorylation of the period protein (PER). This phosphorylation regulates the timing of PER's nuclear accumulation and decline, and it is necessary for the generation of circadian rhythms. In Drosophila melanogaster, mutations affecting a casein kinase I (CKI) ortholog called doubletime (dbt) can produce short or long periods. The effects of both a short-period (dbtS ) and long-period (dbtL ) mutation on DBT expression and biochemistry were analyzed. Immunoblot analysis of DBT in fly heads showed that both the dbtS and dbtL mutants express DBT at constant levels throughout the day. Glutathione S-transferase pull-down assays and coimmunoprecipitation of DBT and PER showed that wild-type DBT, DBTS, and DBTL proteins can bind to PER equivalently and that these interactions are mediated by the evolutionarily conserved N-terminal part of DBT. However, both the dbtS and dbtL mutations reduced the CKI-7-sensitive kinase activity of an orthologous Xenopus laevis CKIδ expressed in Escherichia coli. Moreover, expression of DBT in Drosophila S2 cells produced a CKI-7-sensitive kinase activity which was reduced by both the dbtS and dbtL mutations. Thus, lowered enzyme activity is associated with both short-period and long-period phenotypes.

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Casein kinase I-like protein kinases encoded by YCK1 and YCK2 are required for yeast morphogenesis.

Molecular and Cellular Biology ◽

10.1128/mcb.13.5.2870 ◽

1993 ◽

Vol 13 (5) ◽

pp. 2870-2881 ◽

Cited By ~ 83

Author(s):

L C Robinson ◽

M M Menold ◽

S Garrett ◽

M R Culbertson

Keyword(s):

Protein Kinase ◽

Eukaryotic Cell ◽

Casein Kinase ◽

Temperature Sensitive ◽

Protein Kinase Activity ◽

Restrictive Temperature ◽

Loss Of Function ◽

Casein Kinase I ◽

Yeast Saccharomyces Cerevisiae

Casein kinase I is an acidotropic protein kinase class that is widely distributed among eukaryotic cell types. In the yeast Saccharomyces cerevisiae, the casein kinase I isoform encoded by the gene pair YCK1 and YCK2 is a 60- to 62-kDa membrane-associated form. The Yck proteins perform functions essential for growth and division; either alone supports growth, but loss of function of both is lethal. We report here that casein kinase I-like activity is associated with a soluble Yck2-beta-galactosidase fusion protein in vitro and that thermolabile protein kinase activity is exhibited by a protein encoded by fusion of a temperature-sensitive yck2 allele with lacZ. Cells carrying the yck2-2ts allele arrest at restrictive temperature with multiple, elongated buds containing multiple nuclei. This phenotype suggests that the essential functions of the Yck proteins include roles in bud morphogenesis, possibly in control of cell growth polarity, and in cytokinesis or cell separation. Further, a genetic relationship between the yck2ts allele and deletion of CDC55 indicates that the function of Yck phosphorylation may be related to that of protein phosphatase 2A activity.

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Casein kinase I-like protein kinases encoded by YCK1 and YCK2 are required for yeast morphogenesis

Molecular and Cellular Biology ◽

10.1128/mcb.13.5.2870-2881.1993 ◽

1993 ◽

Vol 13 (5) ◽

pp. 2870-2881

Author(s):

L C Robinson ◽

M M Menold ◽

S Garrett ◽

M R Culbertson

Keyword(s):

Protein Kinase ◽

Eukaryotic Cell ◽

Casein Kinase ◽

Temperature Sensitive ◽

Protein Kinase Activity ◽

Restrictive Temperature ◽

Loss Of Function ◽

Casein Kinase I ◽

Yeast Saccharomyces Cerevisiae

Casein kinase I is an acidotropic protein kinase class that is widely distributed among eukaryotic cell types. In the yeast Saccharomyces cerevisiae, the casein kinase I isoform encoded by the gene pair YCK1 and YCK2 is a 60- to 62-kDa membrane-associated form. The Yck proteins perform functions essential for growth and division; either alone supports growth, but loss of function of both is lethal. We report here that casein kinase I-like activity is associated with a soluble Yck2-beta-galactosidase fusion protein in vitro and that thermolabile protein kinase activity is exhibited by a protein encoded by fusion of a temperature-sensitive yck2 allele with lacZ. Cells carrying the yck2-2ts allele arrest at restrictive temperature with multiple, elongated buds containing multiple nuclei. This phenotype suggests that the essential functions of the Yck proteins include roles in bud morphogenesis, possibly in control of cell growth polarity, and in cytokinesis or cell separation. Further, a genetic relationship between the yck2ts allele and deletion of CDC55 indicates that the function of Yck phosphorylation may be related to that of protein phosphatase 2A activity.

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Oligodeoxyadenylate stimulates the protein kinase activity of anti-DNA sIgA from human milk.

Acta Biochimica Polonica ◽

10.18388/abp.2002_3848 ◽

2002 ◽

Vol 49 (1) ◽

pp. 291-294 ◽

Cited By ~ 2

Author(s):

Yuri Kit ◽

Elena Kuligina ◽

Dimitry Semenov ◽

Vladimir Richter

Keyword(s):

Protein Kinase ◽

Human Milk ◽

Kinase Activity ◽

Protein A ◽

Casein Kinase ◽

Protein Kinase Activity ◽

Stimulation Of

Preparations of anti-DNA sIgA were obtained from human milk by sequential chromatography on protein A-sepharose, DEAE-fractogel and DNA-cellulose. The influence of oligonucleotides on protein kinase activity was investigated. It was discovered that incubation of anti-DNA sIgA with oligodeoxyriboadenylate d(A)12 stimulates the phosphorylation of polypeptides of sIgA in the presence of [gamma-32P]ATP. The greatest was the incorporation of P into the sIgA H-chains. We also demonstrated stimulation of the casein kinase activity of anti-DNA sIgA by d(A)12. The stimulation of the protein kinase activity of anti-DNA sIgA by oligoriboadenylate r(A)12 was not detected.

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The ribosomal proteins phosphorylated in vitro by protein kinase activities from Krebs II ascites cells

Bioscience Reports ◽

10.1007/bf01172872 ◽

1983 ◽

Vol 3 (7) ◽

pp. 621-629 ◽

Cited By ~ 6

Author(s):

Michael J. McGarvey ◽

David P. Leader

Keyword(s):

Protein Kinase ◽

Ribosomal Protein ◽

Ribosomal Proteins ◽

Kinase Activity ◽

Casein Kinase ◽

Protein Kinase Activity ◽

Similar Reaction ◽

Histone Kinase

Studies were performed to identify in cytoplasmic extracts of Krebs II ascites cells protein kinase activities that might be responsible for the phosphorylation of the ribosomal proteins previously identified as phosphoproteins in these cells in vivo. Column chromatography resolved a casein kinase activity that could use ATP or GTP as a phosphoryl donor to phosphorylate, in ribosomes, exclusively the acidic 60S phosphoprotein(s) phosphorylated in vivo. A second casein kinase fraction could use ATP, only, in a similar reaction, but also contained protein kinase activity with respect to other ribosomal proteins, including the basic ribosomal protein phosphorylated in vivo, ribosomal protein S6. This latter was also among several proteins phosphorylated by an activity in the cyclic AMP-independent histone kinase fraction.

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Effect of Thrombin on Phosphorylation of Platelet Membrane Proteins

Thrombosis and Haemostasis ◽

10.1055/s-0038-1647962 ◽

1976 ◽

Vol 35 (03) ◽

pp. 635-642 ◽

Cited By ~ 4

Author(s):

M Steiner

Keyword(s):

Protein Kinase ◽

Kinase Activity ◽

Qualitative Change ◽

Protein Kinase Activity ◽

Protein Substrates ◽

Phosphoprotein Phosphatase ◽

Progressive Loss ◽

Platelet Membranes ◽

Endogenous Protein ◽

Considerable Loss

SummaryThe effect of thrombin on the phosphorylating activity of platelet membranes was compared to that of trypsin. Preincubation of non-32P phosphorylated platelet membranes with or without either of these two enzymes resulted in a considerable loss of membrane protein kinase activity which was most severe when trypsin was used. Protein kinase activity and endogenous protein acceptors decreased in parallel. 32P-phosphorylated membranes showed a slow but progressive loss of label which was accelerated by trypsin. Thrombin under these conditions prevented the loss of 32P-phosphate. These results are interpreted to indicate a thrombin-induced destruction of a phosphoprotein phosphatase. The protein kinase activity of phosphorylated platelet membranes using endogenous or exogenous protein substrates showed a significant reduction compared to non-phosphorylated membranes suggesting a deactivation of protein kinase by phosphorylation of platelet membranes. Neither thrombin nor trypsin caused a qualitative change in the membrane polypeptides accepting 32P-phosphate but resulted in quantitative alterations of their ability to become phosphorylated.

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