Biological
Role
Signals
from
the
environment
(beyond
plasma
membrane)
changes
in
cells
composition
+
function
->
(differentiation
+
antibody
production,
Signaling
Types:
growth/strength
and
sexual/asexual
Antigens
cell
division)
Membrane
bound/soluble
protein/protein
complex
Hormones
exerts
a
physiological
effect
(Intrinsic
effect)
-
after
binding
its
natural
ligand
Neurotransmitters
Receptors:
Signal
Interaction
Light
Examples
of
the
Effects
of
Receptor
-
Agonist
Binding
Message
Transl at io n
to
cells
Touch
I
2
3
ā³
Pheromones
Agonist,
Na
Agonist
Agonist
Agonist
G
protein-coupled
receptors
Epinephrine
receptor
Ā·a
giggle
is
a
gal
all
a
para
al
aaaaaaaaaaaall
gain
a
re
Enzyme-linked
receptors
ā
Ā·-Protein
Insulin
receptors
ActIVatIOn
Actionof
seke's
enter
Terroristen
trie
Ligand-gated
on
channels
ā
conductance
Nicotinic
acetylcholine
recept
or
ā
ā
Activation
of
Activation
of
Activation
of
transcriptionand
Other
membrane
receptors
cell
signaling
cell
signaling
translation
Integrin
receptors
Receptors
Bind
Specific
Ligands
Nuclear
receptors
Steroid
receptors
Typi cal
Ilgands:
small
cons
(a)
Specificity
(d)
Desensitization/adaptation
signal
signal
molecule
fits
receptor
activation
ā
ferric
Ion
->
bacterial
ferric
receptor
binding
site
on
its
trigger
feet"s"
Off
Ā·mplementary
receptor
to
the
the
receptor
or
removes
to
the
fit
It
from
the
cell
surface
Organic
molecules
Response
(b)
Amplification
when
adrenalin
->
epinephrine
receptor
enzymes
activate
enzymes,
10)
Integration
when
molecules
increases
Polysaccharides
the
number
of
affected
on
the
effects
on
a
metabolic
enzyme
cascade.
heparin
->
fibroblasts
growth
factor
enme
.
arsen
a
Sun
remini
have
on
we
can
not
the
ene
Peptides
Response
Insulin
->
Insulin
recept
or
If)
localized
response
(C)
Modularity
Proteins
proteins
with
multivalent
signal
when
the
enzymacte
Far
S
e
affinities
form
diverse
ā§
vascular
endothelial
growth
factor:
VEGF
receptor
signaling
complexes
from
,
inee,
age
stir.
*nort
me
a
ne
interchangeable
parts.
ā³
message
Is
degraded
before
Phosphorylation
provides
I
It
can
diffuse
to
distant
Message
Massage
reversible
points
of
points,
so
the
response
is
Interaction.
ā±
only
local
and
brief
conse
