This calculator explores the phase space of gene regulation as a function of basal (unregulated) rates of transcription
initiation. Unregulated rate constants and polymerase concentration are enetered below in the left column. The fold-change of each parameter generated upon regulation is in the second column and defines a fixed regulatory mechanism. Two basal parameters are selected using the drop-down menus. The X- and Y- parameters will be titrated geometrically from their input value to their input value times the X- and Y-multiplier respectively using the number of points. When the "GO" button is clicked, the mRNA flux fold-change for the defined regulatory mechanism applied to the defined set of basal parameters is calculated and the titrated parameters will be highlighted in the schematic below. The resulting plot is color coded to indicate regions of promoter space that will be activated (flux ratio > 1, green) or repressed (flux ratio < 1, red). Data can be downloaded in CSV format by clicking on the button below at the bottom of the page. See Reference for more information.
fold-change
in mechanism
in mechanism
k
basal
on
nM-1s-1
X-axis:
X-multiplier:
k
basal
off
s-1
Y-axis:
Y-multiplier:
k
basal
open
s-1
Number of Points:
k
basal
close
s-1
Log or Linear:
k
basal
esc
s-1
R
basal
0
nM