Phosphoserine Phosphatase Like Protein (PSPHL)

CO9 cDNA sequence matched those of homologous EST clones in GenBank that had been mapped to 7q11.2. A novel cDNA, which the authors called CO9, was identified. Northern blot analysis revealed that CO9 was significantly upregulated in FA fibroblasts but downregulated or absent in normal fibroblasts. The full-length CO9 cDNA is 840 bp long and encodes a putative 72-amino acid polypeptide with a molecular mass of 7.6 kD. The N-terminal and C-terminal nucleotide sequence of CO9 shows homology to human L-3-phosphoserine phosphatase but lacks a 476-bp stretch in the open reading frame. CO9 may play a role in catalytic phosphorylation/dephosphorylation cycles in regulatory pathways. Periostin, TIMP-2, and PSPHL can be used as predictor genes for the recurrence of pterygia.