CSF: cell communication Flashcards
3 main steps of cell signaling
- reception
- transduction
- response
what happens to receptor proteins during reception
it changes shape or chemical shape
what does reception allow/cause
activation of a protein
what happens in reception
signaling protein binds to receptor protein ie. ligand or first messenger
messages and transduction
gives messages to second messengers
transduction and proteins
each activated protein cause a series of changes via a phosphorylation cascade
Response what happens?
cell does something in response
receptors are?
specific
two types of receptors
Intracellular, cell surface proteins
name two types of cell surface proteins
- G protein-coupled receptor
- Ligand-gated ion channel
what kind of proteins are g protein couples receptors?
Transmembrane proteins
they pass the plasma membrane 7 times
what are the functions of GCPRs?
development, sensory reception - vision, taste, smell
what happens when GCPRs are coupled with G proteins
GPs are molecular switches which are on or off if GDP or GTP is bound
what do ligand gated ion channels contain?
gate
what causes changes in ligand channel shape
binding the ligand at a specific site on the receptor
what can pass through ligand channels and why
- ions pass-through
- channel opens and allows things to pass as it changes shape
what kind of a process is ligand channel transport
passive
what is signal transduction
signals relayed from receptors to target molecules via a ‘cascade’ of molecular interactions
what are the two main secondary receptors
cAMP (cylose acyl - phosphate), calcium 2+
What is the point of secondary messengers cAMP and Ca2+?
phospholipase enzymes activates downstream protein
Ca2+ dangers
concentration must be managed as it can damage and kill cells
6 cellular responses
- gene expression
- alteration of protein function to gain or lose activity
- opening or closing of an ion channel
- alteration of cellular metabolism
- regulation of cellular organelles or organization
- rearrangement/movement of cytoskeleton
Glycogen is a…
long term energy store in liver and skeletal muscle
activation of cell response usually
promotes the start of deactivation
what breaks down CAMP
phosphodiesterase (PDE)
why do we inhibit PDEs
therapeutic approach ie viagra
signals can be
short or long distance
how do signals travel long distance
hormones travel via the circulatory system to specific cells
transduction definition
during transduction pathways multiple proteins may be activated, typical via phosphorylation
