Identification of Cyclin-dependent Kinase 1 Specific Phosphorylation Sites by an In Vitro Kinase Assay
To consistently produce healthy cells, the cell cycle—the process that generates daughter cells—must be precisely regulated.
Internal regulatory checkpoints ensure that a cell’s size, energy reserves, and DNA quality and completeness are sufficient to advance through the cell cycle. At these checkpoints, positive and negative regulators promote or inhibit a cell’s continuation through the cell cycle. Positive regulators include two protein groups that allow cells to pass through regulatory checkpoints: cyclins and cyclin-dependent kinases (CDKs). These proteins are present in eukaryotes, ranging from yeast to humans. Cyclins can be categorized as G1, G1/S, S, or M cyclins based on the cell cycle phase or transition they are most involved in. Generally, levels of a given cyclin are low during most of the cell cycle but abruptly increase at the checkpoint they most contribute to (G1 cyclins are an exception, as they are required throughout the cell cycle). The cyclin is then degraded by enzymes in the cytoplasm and its levels decline. Meanwhile, cyclins needed for the next checkpoints accumulate. To regulate the cell cycle, cyclins must be bound to a Cyclin-dependent kinase (CDK)—a type of enzyme that attaches a phosphate group to modify the activity of a target protein. …
Saccharomyces cerevisiae (commonly known as baker’s yeast) is a single-celled eukaryote that is frequently used in scientific research. S. cerevisiae is an attractive model organism due to the fact that its genome has been sequenced, its genetics are easily manipulated, and it is very easy to maintain in the lab. Because many yeast proteins are similar in sequence and function…
1School of Basic Pharmaceutical and Toxicological Sciences, College of Pharmacy, University of Louisiana Monroe, 2Department of Pharmaceutical Sciences, School of Pharmacy, Texas Tech University Health Sciences Center, 3Department of Obstetrics and Gynecology, School of Medicine, Texas Tech University Health Sciences Center
1Department of Biochemistry, Schulich School of Medicine and Dentistry, University of Western Ontario, 2London Regional Cancer Program, Children's Health Research Institute, and Department of Biochemistry, Schulich School of Medicine and Dentistry, University of Western Ontario
1Division of Developmental Neuroscience, United Centers for Advanced Research and Translational Medicine (ART), Tohoku University Graduate School of Medicine, 2The Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology Corporation (JST)