FIG. 3.

A2RE-1 and A2RE-2 bind to hnRNP A2 in vitro. Biotin-conjugated oligoribonucleotides were immobilized on streptavidin-coated paramagnetic beads and incubated with a protein extract from rat brain. The beads were separated magnetically and washed extensively, and the proteins bound to the beads were eluted and analyzed by SDS-PAGE. The predominant protein, with a molecular mass of approximately 36 kDa, has been previously identified as hnRNP A2. The sequences of the oligoribonucleotides tested were as follows: A2RE, GCCAAGGAGCCAGAGAGCAUG; A2RE A8G, GCCAAGGGGCC; A2RE-1, GACAAGGACCAAAAGAACCCU; A2RE-1 A8G, GACAAGGGCCAAAAGAACCCU; A2RE-2, GAAAUGGAGCCAGTAGAUCCUAG; A2RE-2 A8G, GAAAUGGGGCCAGTAGAUCCUAG; and NSP, CAAGCACCGAACCGGCAACUG.