Biomedical Engineering Reference
In-Depth Information
Figure 3.12.
The response of our model to step-wise changes in uniform concen-
tration of activated receptors. The initial concentration of activated receptors is
S
=1
molecule/μm
and is changed ten-fold at
t
=0
s
and another ten-fold at
t
=50
s
.
spontaneously) there is very little hysteresis when the external gradient is
changed. This latter behavior stands in contrast to what is observed with
instability-based models of gradient sensing [45, 46, 47].
Experimental results to date (see [37] for a full discussion) suggest that
we might be able to identify the model component
A
with
G
α
and the model
component
B
with
G
βγ
.
G
βγ
would then be the inhibitor and
G
α
, in both
its GTP-bound and GDP-bound form, would play the role of activator and
