EXPRESSION SCREENING REVEALS AN ORPHAN RECEPTOR CHICK OVALBUMIN UPSTREAM PROMOTER TRANSCRIPTION FACTOR-I AS A REGULATOR OF NEURITE SUBSTRATE-CELL CONTACTS AND CELL-AGGREGATION

A rat homologue of chick ovalbumin upstream promoter transcription factor I (COUP-TF I) was isolated using an expression cloning method developed to isolate neurite outgrowth inhibitors. Overexpression of COUP-TF I in 3T3 fibroblasts resulted in reduction of stable contact formation between neurites and transfected cells. Additionally, COUP-TF I enhanced retinoic acid response element-dependent reporter gene expression in 3T3 fibroblasts, indicating that COUP-TF I can modulate transcriptional activation in these cells. Our data suggest that COUP-TF transcription factors are involved in the regulation of cell surface molecules during neurogenesis.