Reporter gene without fusion

[Sue4]

I know that a reporter gene can be used to detect the foreign gene expression if it is fused with the foreign gene. But can we monitor the foreign gene expression if we place the reporter gene under a different promoter? If not, what is the use of placing a selectable marker and a reporter gene under the same construct (without a fusion) ?

Thank you
Regards

[JackBean]

If you mean the same promoter just separate (e.g. both under control of bGlu promoter), than the expression should be similar, because it should be on the same locus with the same strenght etc. However, if you mean (and I do not think so) some completely different promoter than of course it won't be the same.