The Functional Significance of Posttranslational Modifications on Polo-Like Kinase 1 Revealed by Chemical Genetic Complementation

Autor: Mark E. Burkard, Natalie G. Trueman, Brittany M. McPherson, Amber Lasek
Rok vydání: 2016
Předmět:
0301 basic medicine
Gene Identification and Analysis
lcsh:Medicine
Cell Cycle Proteins
Polo-like kinase
Biochemistry
Protein-fragment complementation assay
Chromosome Segregation
Cell Cycle and Cell Division
Phosphorylation
Post-Translational Modification
lcsh:Science
Staining
Multidisciplinary
Chromosome Biology
Cell Staining
Cyclin-Dependent Kinases
Precipitation Techniques
Cell Processes
Cell Division
CDC2 Protein Kinase
Research Article
Recombinant Fusion Proteins
Mutation
Missense

Mitosis
Protein Serine-Threonine Kinases
Biology
Research and Analysis Methods
PLK1
03 medical and health sciences
Cyclin-dependent kinase
Proto-Oncogene Proteins
Genetics
Humans
Point Mutation
Immunoprecipitation
Molecular Biology Techniques
Protein Kinase Inhibitors
Molecular Biology
Genetic Complementation Test
lcsh:R
Ubiquitination
Biology and Life Sciences
Proteins
Cell Biology
Protein Structure
Tertiary

Enzyme Activation
Pyrimidines
030104 developmental biology
Amino Acid Substitution
Protein kinase domain
Specimen Preparation and Treatment
Mutagenesis
Site-Directed

Genetic Complementation
biology.protein
Pyrazoles
lcsh:Q
Anaphase
Protein Processing
Post-Translational

Cytokinesis
HeLa Cells
Cloning
Zdroj: PLoS ONE, Vol 11, Iss 2, p e0150225 (2016)
PLoS ONE
ISSN: 1932-6203
DOI: 10.1371/journal.pone.0150225
Popis: Mitosis is coordinated by carefully controlled phosphorylation and ubiquitin-mediated proteolysis. Polo-like kinase 1 (Plk1) plays a central role in regulating mitosis and cytokinesis by phosphorylating target proteins. Yet, Plk1 is itself a target for posttranslational modification by phosphorylation and ubiquitination. We developed a chemical-genetic complementation assay to evaluate the functional significance of 34 posttranslational modifications (PTMs) on human Plk1. To do this, we used human cells that solely express a modified analog-sensitive Plk1 (Plk1AS) and complemented with wildtype Plk1. The wildtype Plk1 provides cells with a functional Plk1 allele in the presence of 3-MB-PP1, a bulky ATP-analog inhibitor that specifically inhibits Plk1AS. Using this approach, we evaluated the ability of 34 singly non-modifiable Plk1 mutants to complement Plk1AS in the presence of 3-MB-PP1. Mutation of the T-loop activating residue T210 and adjacent T214 are lethal, but surprisingly individual mutation of the remaining 32 posttranslational modification sites did not disrupt the essential functions of Plk1. To evaluate redundancy, we simultaneously mutated all phosphorylation sites in the kinase domain except for T210 and T214 or all sites in the C-terminal polo-box domain (PBD). We discovered that redundant phosphorylation events within the kinase domain are required for accurate chromosome segregation in anaphase but those in the PBD are dispensable. We conclude that PTMs within the T-loop of Plk1 are essential and nonredundant, additional modifications in the kinase domain provide redundant control of Plk1 function, and those in the PBD are dispensable for essential mitotic functions of Plk1. This comprehensive evaluation of Plk1 modifications demonstrates that although phosphorylation and ubiquitination are important for mitotic progression, many individual PTMs detected in human tissue may have redundant, subtle, or dispensable roles in gene function.
Databáze: OpenAIRE