16-Cell communication - signal transduction mechanisms Flashcards
What is cell communication?
Ability to sense, interpret and intergrate signals from their environment through biological responses
What is cell signalling?
Simple responses of cells such as growing dividing dying
What are the different forms of cell communication?
Paracrine signalling (local) Synaptic signalling (local) Autocrine signalling (local) Endocrine (long distance) Nervous system (long distance) cell-cell signalling
Describe the mechanism of GPCR (G-protein cell receptor) signalling
Used by diverse ligands for rapid response
GPCR activates G-proteins by swapping GDP for GTP
What is the role of G-proteins in GPCR signalling?
G- proteins activate enzymes that generate “second messengers” in the cell
What are second messengers? and give an example
Small molecules with key functions inside cells
cAMP
How Receptor Tyrosine kinase (RTK) signalling functions?
Receptors form dimers that span the plasma membrane more than once
Receptors are enxzymes that phosphorylate tyrosine amino acids
What is the role of tyrosine phosphorylation?
On/Off switch for RTKs depend on phosphorylation of tyrosine
What are examples of local cell signalling?
Contact Cell- cell signalling Paracrine Autocrine Synaptic
What are examples of long distance cell signalling?
Endocrine
Neuronal
What is paracrine signalling?
Signalling in which the target cell is close to the signal releasing cell, and signal chemical is broken down too quickly to be carried to other parts of the body
What is synaptic signalling?
From a nerve to a target cell
What is autocrine signalling?
Is a form of signalling in which a cell secretes a chemical messenger that signals the same cell
Name different types of cellular receptors that are plasma membrane bound
G-protein coupled receptors
Enzyme linked receptors
Ion channel receptors
Name different types of cellular receptors that are intracellular?
steriod hormones
