9 - Signaling Pathways Directing Cell-Polarization I Flashcards
What is cell signaling necessary for?
Communications of the cell within itself or among cells in different tissues
What must cells take in information about?
Their environment, and their internal state
What decisions do cells have to make?
- What genes should be turned on/off?
2. What proteins should be activated/deactivated?
What are some responses cells could have through cell signaling?
Grow, divide, develop (migrate, change shape, etc.), survive, or die
What is cell signaling?
A language that cells use to communicate with one another and within themselves
True or false: the response of a cell is very specific
True: the nature of the signal and the integration of different signals makes the response highly specific
True or false: a signaling unit refers to a collection of proteins in a network
False: there are many different scales of signaling units (cell, protein, amino acid, etc.)
What is meant by the “universal nature” of signaling determinants?
While the context of the class will focus on neuronal development, these signaling determinants are found across different cells and different organisms as well
What is a state machine?
A machine that can acquire different states
What are some biological examples of state machines?
The whole cell, signaling determinants, etc.
What is a mechanical example of a state machine?
An automatic door
How does a state machine work?
An input changes the state of the machine, which leads to a different, specific function
When does a state machine change its state?
When it responds to a stimuli
True or false: a state machine can only be in two states
False: it can be in many different states depending on the state machine
Why can the cell be considered a state machine?
They take in inputs, change their state, and perform a specific function based on that state
What are some example states a cell could have?
Proliferating (growing), quiescent (surviving), and apoptotic (dying)
What are the different states controlled by?
Environmental inputs
True or false: a state machine can only have one input
False: it can integrate a combination of inputs
What is an example of states a protein can be in?
Phosphorylated or non-phosphorylated, ligand bound or non-ligand bound
What determines whether a kinase is active or inactive?
Its phosphorylation state
What determines whether a receptor is active or inactive?
Whether it is bound to a ligand
What is meant by a “hierarchal organization” of signaling devices?
Many components are signaling devices (organism -> cell -> kinase)
True or false: an amino acid in a protein can be a signaling device
True: there can be many scales of signaling devices
What is meant by an “upstream downstream hierarchy”?
Can have signaling events in order from beginning (upstream) to end (downstream)
