Bio-Rad EXQuest Spot Cutter - Manual (Page 222)

Analysis Tools
6-31
For a graphical display of the overall trend of MrpI values across the entire gel, first
make sure the Master subwindow is active, then select Plot MrpI Grid from the
Analyze > MrpI Standards submenu or toolbar.
Fig. 6-23. MrpI grid with values in the Spot Parameters dialog.
A grid of MrpI axes will appear over the Master. You can use the grid to verify that
the values that you entered make sense; you can also use it to estimate the MrpI
values of proteins of interest.
To see the exact MrpI values of a spot, select Spot Parameters from the Spots menu or
toolbar and click the spot, or use the F6 key command on the spot. The MrpI values
are displayed in the pop-up box.
Note: If the isoelectric point value of the spot falls outside the highest and lowest
known values, the pI value will not be calculated. Empirical results have shown
that extrapolated pI values are unreliable, due to gel distortions and other factors.
Transferring MrpI Data in a Higher Level MatchSet
Transfer MrpIs allows you to apply the molecular weight and isoelectric point values
from one higher level MatchSet member to the other members. This makes it easier to
correlate data from the member MatchSets. (See section 5.8.b, Higher Level
MatchSets for more information on higher level MatchSets.)