Fig. 1. Schematic representation of chromatin immunoprecipitation experiments. (A) Outline of ChIP experiment in retina and optic tectum. Dissected tissues were homogenized in the presence of formaldehyde. Crosslinked chromatin was prepared using a standard procedure, sonicated and incubated with appropriate antibodies. Specific DNA fragments in immunoprecipitates were quantified by real-time PCR. (B) Retinal ganglion cells (RGC) isolated using panning with anti-THY1 antibody. Dissociated retinal cells expressing THY1 were retained on dishes coated with anti-THY1 antibody and fixed with formaldehyde. Fixed cells were processed for ChIP as in A. (C) Schematic representation of upstream regions of the analyzed genes. The black squares are E-boxes and arrows indicate the primers used for amplification.