Figure 4.

CRX accounts for the pineal-retina specific binding activity. (A) Supershift assay with an anti-CRX antiserum. The same probe as in Fig. 3B was used. The antiserum was incorporated in EMSAs with a series of nuclear extracts indicated. The arrow indicates the position of supershifted band that is absent when no antibody or no nuclear extracts was incorporated. (B) DNase I footprint assay of PINA intronic promoter. A ³²P end-labeled PINA promoter fragment was incubated with or without CrxHD-glutathione S-transferase fusion protein (8). Protected regions are indicated by brackets with the nucleotide positions indicated. The positions of PIREs are indicated by solid bars.