Signaling #1 Flashcards
What is cell signaling?
Process by which cells recognize and respond to environmental changes
What are the basic elements of cell signaling?
- Signal
- Ligand/first messenger
- Receptor
- Biochemical response
- Cellular response
What is signal transduction?
Process whereby chemical signals elicit intracellular changes
What are the four modes of action in cell signaling?
- Allostery
- Covalent modification
- Proximity
- Ligand binding
What are ligands in cell signaling?
Hormones, growth factors, gases – 1st messengers
What role do receptors play in cell signaling?
Detect incoming signals and transfer information to internal signaling pathways
What is the significance of defects in cell signaling?
They underlie disease mechanisms and associated aberrant cell responses
True or False: All receptors are transmembrane proteins.
False
What is the function of histone acetyltransferases (HATs) in cell signaling?
Acetylate lysine residues on histones, facilitating transcription
Fill in the blank: The first to show that adrenal glands are essential to life was _______.
[Charles-Édouard Brown-Séquard]
What are agonists in the context of receptors?
Mimic the function of the ligand
What are antagonists in the context of receptors?
Bind to the receptor but do not elicit a response
What is the role of estrogen receptors in cell signaling?
Bind to DNA and associate with co-activators to stimulate transcription
What is the daily testosterone secretion amount in humans?
6 mg (6,000,000 ng)
What is the primary focus of the study of cell signaling?
Understanding how signaling molecules initiate physiological responses
How does ligand binding to a receptor affect the receptor’s function?
It must be specific and saturable
What is the speed of signal transmission for ion channels?
Very fast (milliseconds)
What factors determine the sensitivity of a cell to signaling?
Number and type of cell surface receptors
What is the effect of acetylation on histones?
Decreases interaction of histone with DNA, allowing gene regulation
What is the historical significance of Charles-Édouard Brown-Séquard?
Considered the father of modern endocrinology and first to demonstrate internal secretions’ effects
What are intracellular mediators in cell signaling?
- Adaptor proteins
- Docking proteins
- GTP binding proteins
What are effector proteins in a signaling pathway?
- Protein or lipid kinases
- Phosphodiesterases
- Metabolic enzymes
What is the purpose of using microarrays in cell signaling studies?
To examine how gene expression changes in response to ligand binding
What does HDAC stand for?
Histone Deacetylase
What does HAT stand for?
Histone AcetylTransferase
Give an example of a Histone AcetylTransferase.
p300
What is often studied to understand gene expression changes?
Exposure to different environmental stimuli or ligands
In the microarray experiment, what are the two conditions compared?
Serum-treated cells vs serum-deprived cells
What color represents serum-induced genes in the microarray?
RED
What color represents serum-inhibited genes in the microarray?
GREEN
How many different genes were analyzed in the study mentioned?
8613 different genes
Who are the authors of the study referenced?
V R Iyer et al.
In which journal was the referenced study published?
Science
What year was the referenced study published?
1999
What is the purpose of microarray DNA chip analysis?
To study signaling in live tissues or cells
Fill in the blank: Microarray analysis is used to study _______ in serum-stimulated fibroblasts.
signaling
