Cloning, nucleotide sequence, and chromosome localization of the human pleiotrophin gene

Pleiotrophin (PTN), midkine (MK), and retinoic acid-induced heparin-binding (RI-HB) protein are members of a recently discovered family of developmentally regulated cytokines. We report here the cloning, sequencing, chromosomal localization, and structural organization of the genomic version of the human PTN gene and its comparison to the mouse MK. The PTN gene was found to be arranged in five exons and four introns, in a fashion similar to that of the mouse MK gene. Exon 1, as for MK, does not appear to encode amino acid sequence