I’m currently trying to make some germline fluorescent reporters using the Mos single copy insertion system. I have a huge number of transformants, but none of them are expressing my reporter, and most seem to be stably maintaining their extrachromosomal arrays. Is there any way to increase the rate at which worms will lose extrachromosomal arrays?
are you sure that they’re not integrants of the array that express too weakly to see the GFP by your expected means?
outcrossing the array can decrease the frequency of transmission of the array to progeny.
could it be possible that you integrated your intended sequence as well as the backbone/array marker?