boule acide

CONT: The DNA-binding domains appear to have well-defined structural motifs: by contrast, mutational studies of the activator domains suggest a disquieting picture of a conformationally ill-defined polypeptide that can function almost irrespective of sequence, provided only that there is a sufficient excess of acidic residues clustered or peppered about. Thus, the elegant molecular machinery that so reliably controls expression of eukaryotic polymerase II-transcribed genes relies on nearly shapeless molecular components dubbed ""acid blobs"" or perhaps more aptly ""negative noodles"".