Cloning and characterization of a chicken platelet-derived growth factor B-chain cDNA

Avian thrombocytes are nucleated blood cells homologous in function to mamm alian platelets. In the present study, we obtained a cDNA from chicken thro mbocyte polyadenylated RNA [Poly(A) + RNA], which coded for the chicken PDG F-B chain. The sequence was 1083-bp long and had an open reading frame (ORF ) of 753-bp. At the amino acid level, the predicted mature protein showed 6 9% homology with the processed coding region of human PDGF-B. Reverse trans criptase-polymerase chain reaction (RT-PCR) analysis showed that PDGF-B mRN A was expressed at high levels in thrombocytes and in the lung. The express ion of PDGF-B chain mRNA in thrombocytes reached its maximum level 12 It fo llowing type I collagen treatment. These results suggest that chicken PDGF- B chain may play an important role in the vascular system and in healing wo unded tissue. (C) 2001 Elsevier Science Ltd. All rights reserved.