The gene (PTPIM13) encoding the protein tyrosine phosphatase PTP-BL/PTP-BAS is located in mouse chromosome region 5E/F and human chromosome region 4q21

Both mouse and human genomic clones were isotively). Using these clones as a probe, PTPN 13 was assigned to lated for protein tyrosine phosphatase PTP-BL/PTP-BAS human chromosome region 4q21 and mouse chromosome (HGM approved gene symbols Ptpnl3 and PTPN13, respecregion 5E/F by fluorescence in situ hybridization (FISH). Protein tyrosine kinases (PTKs) can exert growth stimulatophosphatase domain is present. In between are five 80 amino ry responses by transient phosphorylation of cellular protein acids repeats, a protein motif that is also found in the Drosophtyrosine residues. Protein tyrosine phosphatases (PTPases) ila discs-large tumor suppressor. These discs-large homologous were, therefore, considered negative regulators of cell growth regions (DHRs) have now been identified in a large number of and differentiation. However, evidence is accumulating that PTPases can also stimulate cell proliferation and maturation ing signals (Ponting and Phillips, 1995). Recently, it was shown and can work in concert with PTKs in signal transduction paththat one of the DHRs of PTP-BAS can associate with the reguways (Brady-Kalnay and Tonks, 1994). Over 30 PTPase family latory region of Fas, thereby inhibiting Fas-i members have been characterized, displaying different struc(Sato et al., 1995). Since tissue homeostasis is ; to act as s (Walton balanced cell proliferation and cell death, Recently, we obtained mouse partial cDNA clones encoding PTP-BAS expression levels or activities might the PTPase PTP-BL (Accession number Z3274Q; Hendriks et cal consequences, al., 1995) which has also been cloned by others and termed RIP Knowledge of the exact c (Chida et al., 1995). The deduced amino acid sequence of will facilitate studies that address the murine PTP-BL displays 80 % overall sequence homology with PTP-BL/PTP-BAS in tumorigenesis. of PTPN 13 human PTP-BAS awa et al„ 1994), also known as to mouse c 5 hPTPIE (Banville et a l, 1994) or PTPL1 (Saras et al., 1994). human chromosome 4, using inters Like its human homolog PTP-BAS, PTP-BL shares intriguing (Chida et al., sequence homologies with submembranous tumor suppressors. It contains a band 4 .1-like motif also present in the tumor sup­ pressors neurofibromatosis type 2 and e er et al., 1993). At the carboxy-terminal end the si \ or PCR on a p 1994), respectively. We used refine situ PTP-BAS chromosome region 4q21, respectively. :e in location of the PTP-BL/ Supported by a grant from the Dutch Cancer Society (Koningin Wilhelmina Fonds). Materials and methods Received 27 July 1995; revision accepted 22 May 1996. Dr. W.J.A.J, Hendriks, of Cell Biology and Histology, University I, P.O. Box 910!, 6500 HB .‘gen. s: +31 24 3614334; lax: +31 24 3540525. Two liai 6.5-kb of mouse PTP-BL genomic clows fragments of 1.1 kb and 1.3 kb were isolated from the par* s et al., s were labeled radloactively and used to screen a mouse strain genomic cosmid library. Positive clones were purified by subseKÀRfîFR E-mail karger(o'karger.ch IV/ \IVVJ I. IV Fax +4] 61 3()6 12 34 h ttp :// www. karger, ch © 1996 S, Karger AG, Basel 030 i -0171/96/0742-015 3£ 10.00/0