soluble protein expression in E. coli

[Saverio Brogna Genetics]

Dear someone,

I have expressed a Drosophila protein  in E. coli by using several 
strategies (unfused, fused to glutation transferase, and fuse to 6-His 
tag) but all of it is unsoluble.
DO YOU KNOW OF ANY WAY TO EXPRESS PROTEINS IN E. COLI THAT ARE SOLUBLE?

THANKS SAVERIO
-- 
Saverio Brogna
University of Cambridge, Departement of Genetics
Downing Street, Cambridge, CB2 3EH, England (UK)
tel +44-223-333970, fax +44-223-333992