STRUCTURE OF THE MURINE MPTP-PEST GENE - GENOMIC ORGANIZATION AND CHROMOSOMAL MAPPING

Protein tyrosine phosphatases comprise a large family of enzymes that are involved in the control of cellular tyrosine phosphorylation. We h ave used lambda phage analysis to elucidate the complete genomic struc ture of an intracellular member of this family, the murine MPTP-PEST g ene. Eight overlapping lambda phage clones representing the MPTP-PEST locus were isolated from a 129/sv mouse genomic library. The gene span s over 90 kb of the mouse genome and is composed of 18 exons, 10 of wh ich constitute the catalytic phosphatase domain Detailed comparison of the position of intron/exon boundaries of the phosphatase domain of M PTP-PEST to those of several other protein tyrosine phosphatases indic ates that the MPTP-PEST catalytic domain contains additional exons as a consequence of the insertion of novel introns. In addition, this ana lysis reveals a strong conservation of the genomic organization within the catalytic domain of the protein tyrosine phosphatase gene family. Finally, fluorescence in situ hybridization with MPTP-PEST genomic DN A refines the map position of MPTP-PEST to mouse chromosome 5A3 to B. This result is in agreement with the previous mapping of the human PES T gene to chromosome 7q11.23, a region of synteny with the centromeric portion of mouse chromosome 5. (C) 1995 Academic Press, Inc.