protein/nucleic acid motifs

[Dr. P.A. Crossey]

I've got a query about a protein/nucleic acid motif. Can anybody help? The protein I'm studying has seven tandemly repeated copies of an acidic pentamer of the general form Gly-X-Glu-Glu-X where X is variant. Has anybody come across this motif or a similar one before.Is the fact that the motif is highly acidic important? Because there may be alternate initiation of translation this motif may lie in the 5'UTR of the gene so the same question applies with respect to nucleic acid motif. Finally could someone recommend a good review dealing with motifs.Thanks. By the way I have searched motif databases but with no joy.