GFP expression and RNAi?

[laura-berkowitz at utulsa.edu]

Hi,
    I have an odd situation that I was wondering about.
    I have been trying to get embryonic expression of a GFP fusion gene 
using the unc-119; pie::GFP plasmid introduced by bombardment. I have 
gotten several transformed lines, none of which show any GFP. But about 
1/3 of the lines show an exact phenocopy of the mutant phenotype 
normally exhibited by loss-of-function mutations.  Since no GFP is seen 
I think it is unlikely it could be from over- or misexpression. I also 
antibody stained for the protein and could no longer see it (not even 
the endogenous)-- suggesting some sort of RNAi-like effect!
    Has anyone seen or heard of this happening?
    Does anyone have a suggestion how to stop it or actually get GFP 
expression?
    Thanks in advance for your thoughts.

                                    Laura

-- 
Laura A. Berkowitz, Ph.D.
Assistant Professor
Dept. of Biological Sciences
University of Tulsa
600 S. College Ave.
Tulsa,  OK  74104-3189

Office: (918) 631-2018
Lab: (918) 631-3127
Fax: (918) 631-2762


---