strange behaviour of integrant

Morris Maduro Morris_maduro at
Thu Mar 9 06:41:44 EST 1995

Hello once again,

Thanks to all those who sent replies to my inquiries regarding integration
of transgenic arrays.  I screened 300 plates of cloned F2's and recovered a
strain that gives 100% transmission.  The original array consisted of pRF4
and an unc-119::GFP fusion plasmid.  All of the animals of this strain
fluoresce and all are right-handed rollers.

I crossed a few of these putative integrants with N2 males, and almost all
the progeny failed to roll.  Those that did (only a few) rolled very
weakly.  All of the F1's did fluoresce, however, although apparently
slightly weaker than the parent strain.  In the F2, the strong right-hand
rol phenotype resegregated, and of those, all fluoresced, and brighter than
the F1's.

It looks like the rol-6D (su1006) has become recessive, maybe due to some
kind of position effect.  Either that, or I've integrated the array
_without pRF4_ into a rol gene.  (Of course, the apparent recessive nature
of the rol-6 marker makes crossing the 'integrant' easier since the F1
males mate well.  Also it will be easier to map it.)

Has anyone else had this happen?  As far as I know the F1s should all roll
if it is a true integrant.  I'm in the process of backcrossing the F1 males
to the original 'integrant' strain to test for recessive rol.

I'd appreciate any comments.

Morris Maduro
Dept of Biological Sciences
University of Alberta
Edmonton, AB Canada          Morris_maduro at

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