Leucine Rich Repeat In FLII Interacting Protein 1 (LRRFIP1)

The GCF2 cDNA contains an internal region with 98% nucleotide identity with the first 309 bp of the GCF cDNA, but the remainder of the 2 sequences share no significant homology.

The predicted 752-amino acid GCF2 protein has a pI of 4.4. The authors confirmed the calculated molecular mass of 83 kD by mass spectroscopy. However, GCF2 migrates as a 160-kD protein by SDS-PAGE. the discrepancy between the calculated and observed masses is due either to the acidic nature of the protein or to an unusual ability of GCF2 to form very stable dimers. GCF2 binds to EGFR promoter fragments in vitro. Cotransfection assays showed that GCF2 represses transcription from 3 different promoters, including that of EGFR.