Related Experiment Video
Updated: Jul 10, 2026
08:36
Metabolic Mapping: Quantitative Enzyme Cytochemistry and Histochemistry to Determine the Activity of Dehydrogenases in Cells and Tissues
Published on: May 26, 2018
Correlating enzyme activity and cellular behavior
1Department of Chemistry, University of Georgia, Athens, GA 30602-2556, USA. tdore@chem.uga.edu
Chemistry & Biology
|November 21, 2007
Summary
A novel photoactivatable sensor tracks protein kinase C (PKC) activity during cell division. PKCbeta is active before nuclear envelope breakdown but not after, revealing its role in mitosis.
Area of Science:
- Biochemistry
- Cell Biology
- Molecular Biology
Background:
- Protein kinase C (PKC) plays crucial roles in cellular signaling pathways, including cell division.
- Monitoring PKC activity in real-time within living cells during mitosis is challenging due to the dynamic nature of the process.
Discussion:
- The study introduces a photoactivatable phosphorylation sensor for visualizing PKC activity.
- Isoform-specific inhibitors were used to target and study protein kinase C beta (PKCbeta).
- The sensor allowed for temporal monitoring of enzyme activity during specific stages of mitosis.
Key Insights:
- PKCbeta activity was detected prior to the breakdown of the nuclear envelope.
- PKCbeta activity was found to be absent after nuclear envelope breakdown.
- This suggests a specific temporal requirement for PKCbeta during early mitotic events.
Outlook:
- This methodology can be applied to study other kinases and their roles in cell cycle progression.
- Further research can elucidate the precise substrates and functions of PKCbeta during mitosis.
- Developing advanced imaging techniques can provide deeper insights into kinase signaling networks.
Related Concept Videos
01:19Regulation of Metabolism
Cellular needs and conditions vary from cell to cell and change within individual cells over time. For example, the required enzymes and energetic demands of stomach cells are different from those of fat storage cells, skin cells, blood cells, and nerve cells. Furthermore, a digestive cell works much harder to process and break down nutrients during the time that closely follows a meal compared with many hours after a meal. As these cellular demands and conditions vary, so do the amounts and...
01:19Enzyme Kinetics
Enzymes speed up reactions by lowering the activation energy of the reactants. The speed at which the enzyme turns reactants into products is called the rate of reaction. Several factors impact the rate of reaction, including the number of available reactants. Enzyme kinetics is the study of how an enzyme changes the rate of a reaction.
Scientists typically study enzyme kinetics with a fixed amount of enzyme in the controlled environment of a test tube. When more reactant, or substrate, is...
Scientists typically study enzyme kinetics with a fixed amount of enzyme in the controlled environment of a test tube. When more reactant, or substrate, is...
01:00Enzyme-linked Receptors
Enzyme-linked receptors are proteins that act as both receptor and enzyme, activating multiple intracellular signals. This is a large group of receptors that include the receptor tyrosine kinase (RTK) family. Many growth factors and hormones bind to and activate the RTKs.
Neurotrophin (NT) receptors are a family of RTKs, including trkA, trkB, and trkC (tropomyosin-related kinase) receptors. TrkA is specific for nerve growth factor (NGF), neurotrophin-6, and neurotrophin-7. TrkB binds...
Neurotrophin (NT) receptors are a family of RTKs, including trkA, trkB, and trkC (tropomyosin-related kinase) receptors. TrkA is specific for nerve growth factor (NGF), neurotrophin-6, and neurotrophin-7. TrkB binds...
02:34Enzymes
Inside living organisms, enzymes act as catalysts for many biochemical reactions involved in cellular metabolism. The role of enzymes is to reduce the activation energies of biochemical reactions by forming complexes with its substrates. The lowering of activation energies favor an increase in the rates of biochemical reactions.
Enzyme deficiencies can often translate into life-threatening diseases. For example, a genetic abnormality resulting in the deficiency of the enzyme G6PD...
Enzyme deficiencies can often translate into life-threatening diseases. For example, a genetic abnormality resulting in the deficiency of the enzyme G6PD...
01:22Amplifying Signals via Enzymatic Cascade
When a ligand binds to a cell-surface receptor, the receptor's intracellular domain changes shape, which may either activate its enzyme function or allow its binding to other molecules. The initial signal is amplified by most signal transduction pathways. This means that a single ligand molecule can activate multiple molecules of a downstream target. Proteins that relay a signal are most commonly phosphorylated at one or more sites, activating or inactivating the protein. Kinases catalyze the...
01:13Enzymes and Activation Energy
The activation energy (or free energy of activation), abbreviated as Ea, is the small amount of energy input necessary for all chemical reactions to occur. During chemical reactions, certain chemical bonds break, and new ones form. For example, when a glucose molecule breaks down, bonds between the molecule's carbon atoms break. Since these are energy-storing bonds, they release energy when broken. However, the molecule must be somewhat contorted to get into a state that allows the bonds to...