Are the background genes appear in gene regulatory network?

Question

[someone]

Hello,

I use SynTReN Tool from :

http://www.biomedcentral.com/1471-2105/7/43/

The tool -that create gene network - provide me to change number of background genes

and the relation between any background genes are "de" examples:

araC du araBAD
araC du araE

My question is :

Does these relations between background genes appear in the network? and what does of "du" mean?

Thank you