Cell-Cell Communication Flashcards
Describe chemical mediators
small molecules, specific
Examples of signalling molecules
gases, amino acids, small peptides, proteins, steroids,
Describe steroid hormones
lipophilic molecules, intracellular receptors
Where is cortisol produced
zona fasciculata of adrenal cortex
What does sildefanil interfere with
signalling by nitric oxide
Name two types of signalling
passive diffusion, direct cell-cell contact
Where is nitric oxide produced
epithelial cells
What is the effect of nitric oxide
relaxes smooth muscles
How does nitric oxide signal
passive diffusion
What is nitric oxide synthesised by
enzyme found in endothelial cells
What are gap junctions used a lot for
co-ordinating muscle contraction
Is the ligand secreted for contact dependent receptors
No
Describe the ligand and receptors in contact-dependent receptors
membrane proteins
What do contact dependent receptors communicate with
neighbouring cells, extracellular matrix
What are contact dependent receptors used for
neuronal development, NK cells and cancer cells
What distance does autocrine signalling cover
very short distances
Describe autocrine signalling
signalling cell secretes a ligand which binds to own receptors
Where does autocrine signalling signal to
it self - cell
Where is autocrine signalling used and why
nervous system - prevents overstimulation
What distance does paracrine signalling cover
short distance
What drug can interfere with paracrine signalling
aspirin
WHat does paracrine signalling signal to
neighbouring cells
What distance does endocrine signalling cover
long distances
Examples of endocrine signalling glands
islet of langerhans, thyroid gland
What are the signalling molecules used by endocrine signalling
hormones
What are the neurotransmitters called in synaptic signalling
ligands
What do intracellular signalling cascades involve
relay, adaptor, bifurcation proteins
What is the function of bifurcation proteins
take message to other signallign pathway
What is the function of transducer proteins
convert signal into another form
What is the function of integrator proteins
integrate signal from different signalling pathways
What is the effect on latent gene regulatory proteins when they are activated
migrate to nucleus
What is the function of adaptor proteins
bring signalling molecules close together
What is the function of intracellular signalling cascades
stronger combined response - integrate pathways
What types of loops can intracellular signalling cascades have
positive or negative feedback loops
What is the function of scaffold proteins
bind multiple relay proteins, improve precision, limit diffusion of pathway
What do scaffold proteins reduce
opportunities for amplification
