INVOLVEMENT OF A SINGLE-STRANDED-DNA BINDING-PROTEIN, SSCRE-BP PUR-ALPHA, IN MORPHINE-DEPENDENCE/

We have purified a nuclear protein from mouse cerebella that binds to single-stranded oligo-DNA of cAMP response element and is modulated by morphine treatment. Isolation of the cDNA clone showed that the nucle ar protein (ssCRE-BP) was identical to Pur alpha, a DNA binding protei n for single-stranded purine-rich sequences that was originally isolat ed as a replication factor. ssCRE-BP/Pur alpha and mRNA were abundant in the brain. The levels of ssCRE-BP/Pur alpha and the transcript were not changed by chronic morphine treatment, however, the levels of an activator of ssCRE-BP/Pur alpha which is necessary for the DNA binding , may be modulated by the treatment.