Characterization of an activated human ros gene.

A human oncogene, mcf3, previously detected by a combination of DNA-mediated gene transfer and a tumorigenicity assay, derives from a human homology of the avian v-ros oncogene. Both v-ros and mcf3 can encode a protein with homology to tyrosine-specific protein kinases, and both mcf3 and v-ros encode a potential transmembrane domain N terminal to the kinase domain. mcf3 probably arose during gene transfer from a normal human ros gene by the loss of a putative extracellular domain. There do not appear to be any other gross rearrangements in the structure of mcf3.

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Molecular cloning, functional expression and characterization of two serine/threonine-specific protein kinases from Nicotiana tabacum pollen

Sexual Plant Reproduction ◽

10.1007/s00497-004-0228-6 ◽

2004 ◽

Vol 17 (4) ◽

pp. 165-175 ◽

Cited By ~ 4

Author(s):

Kumara Dissanayake ◽

Carlos Castillo ◽

Takeshi Takasaki ◽

Tetsu Nakanishi ◽

Naoko Norioka ◽

...

Keyword(s):

Nicotiana Tabacum ◽

Molecular Cloning ◽

Protein Kinases ◽

Functional Expression ◽

Specific Protein

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The Extracellular Domain of the Saccharomyces cerevisiae Sln1p Membrane Osmolarity Sensor Is Necessary for Kinase Activity

Journal of Bacteriology ◽

10.1128/jb.181.8.2527-2534.1999 ◽

1999 ◽

Vol 181 (8) ◽

pp. 2527-2534 ◽

Cited By ~ 39

Author(s):

Darin B. Ostrander ◽

Jessica A. Gorman

Keyword(s):

Saccharomyces Cerevisiae ◽

Leucine Zipper ◽

Transmembrane Domain ◽

Active Form ◽

Extracellular Domain ◽

Kinase Domain ◽

Mitogen Activated Protein Kinase ◽

High Osmolarity ◽

Mitogen Activated Protein ◽

Regulation Of Activity

ABSTRACT The function of the extracellular domain (ECD) of Sln1p, a plasma membrane two-transmembrane domain (TMD) sensor of the high-osmolarity glycerol (HOG) response pathway, has been studied in the yeastSaccharomyces cerevisiae. Truncations of SLN1that retain an intact kinase domain are capable of complementing the lethality of an sln1Δ strain. By observing levels of Hog1p phosphorylation as well as the phosphorylation state of Sln1p, the kinase activities of various SLN1 constructions were determined. In derivatives that do not contain the first TMD, Sln1p activity was no longer dependent on medium osmolarity but appeared to be constitutively active even under conditions of high osmolarity. Removal of the first TMD (ΔTMD1 construct) gave a protein that was strongly phosphorylated whereas Hog1p was largely dephosphorylated, as expected if the active form of Sln1p is phosphorylated. When both TMDs as well as the ECD were deleted, so that the kinase domain is cytosolic, Sln1p was not phosphorylated whereas Hog1p became constitutively hyperphosphorylated. Surprisingly, this hyperactivity of the HOG mitogen-activated protein kinase signaling pathway was not sufficient to result in cell lethality. When the ECD of the ΔTMD1 construct was replaced with a leucine zipper motif, Sln1p was hyperactive, so that Hog1p became mostly unphosphorylated. In contrast, when the Sln1p/leucine zipper construct was crippled by a mutation of one of the internal leucines, the Sln1 kinase was inactive. These experiments are consistent with the hypothesis that the ECD of Sln1p functions as a dimerization and activation domain but that osmotic regulation of activity requires the presence of the first TMD.

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Characterization of two tyrosine-specific protein kinases from pig spleen. Substrate-specific effect of autophosphorylation

European Journal of Biochemistry ◽

10.1111/j.1432-1033.1990.tb19450.x ◽

1990 ◽

Vol 194 (1) ◽

pp. 251-258 ◽

Cited By ~ 19

Author(s):

Andreas G. BATZER ◽

Sabine KIRSCH ◽

Hans Werner HOFER

Keyword(s):

Protein Kinases ◽

Specific Effect ◽

Specific Protein

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Phosphorylation, Mg-ADP, and Inhibitors Differentially Shape the Conformational Dynamics of the A-Loop of Aurora-A

Biomolecules ◽

10.3390/biom11040567 ◽

2021 ◽

Vol 11 (4) ◽

pp. 567

Author(s):

Zahra Musavizadeh ◽

Alessandro Grottesi ◽

Giulia Guarguaglini ◽

Alessandro Paiardini

Keyword(s):

Protein Kinases ◽

Kinase Inhibitors ◽

Conformational Dynamics ◽

Md Simulations ◽

Kinase Domain ◽

General Description ◽

Aurora A ◽

Post Translational Modification ◽

The Stability

The conformational state of the activation loop (A-loop) is pivotal for the activity of most protein kinases. Hence, the characterization of the conformational dynamics of the A-loop is important to increase our understanding of the molecular processes related to diseases and to support the discovery of small molecule kinase inhibitors. Here, we carry out a combination of molecular dynamics (MD) and essential dynamics (ED) analyses to fully map the effects of phosphorylation, ADP, and conformation disrupting (CD) inhibitors (i.e., CD532 and MLN8054) on the dynamics of the A-loop of Aurora-A. MD revealed that the stability of the A-loop in an open conformation is enhanced by single phospho-Thr-288, while paradoxically, the presence of a second phosphorylation at Thr-287 decreases such stability and renders the A-loop more fluctuant in time and space. Moreover, we found that this post-translational modification has a significant effect on the direction of the A-loop motions. ED analysis suggests that the presence of the phosphate moiety induces the dynamics of Aurora-A to sample two distinct energy minima, instead of a single large minimum, as in unphosphorylated Aurora-A states. This observation indicates that the conformational distributions of Aurora-A with both single and double phospho-threonine modifications are remarkably different from the unphosphorylated state. In the closed states, binding of CD532 and MLN8054 inhibitors has the effect of increasing the distance of the N- and C-lobes of the kinase domain of Aurora-A, and the angle analysis between those two lobes during MD simulations showed that the N- and C-lobes are kept more open in presence of CD532, compared to MLN8054. As the A-loop is a common feature of Aurora protein kinases, our studies provide a general description of the conformational dynamics of this structure upon phosphorylation and different ligands binding.

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