DEX induction problems

[Nobody]

Dear Colleagues,

We are having problems with DEX induction of a transcription 
factor-glucocorticoid receptor fusion (BBM-GR) in young seedlings. 
The seeds are plated on =BD MS + 1% sucrose containing 10 um DEX and 
scored for somatic embryo formation up to 10 days after germination. 
The problem we are experiencing is that the same seed batch responds 
differently to the DEX induction when plated at different times; 
sometimes the phenotypes are very strong, while at other times only 
very weak phenotypes are observed. We have ruled out any problems 
related to seed vigour and the stability of the DEX solution. We are 
wondering if the variable phenotypes could be related to the 
efficiency of DEX uptake by the seedlings, e.g. could the amount of 
moisture in the plates affect DEX uptake?  We would be interested to 
hear from other groups who have experienced (and solved!) similar 
problems.

Thanks,

Kim Boutilier
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