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J. Biol. Chem., Vol. 279, Issue 34, 35768-35774, August 20, 2004

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The Minimal Essential Core of a Cysteine-based Protein-tyrosine Phosphatase Revealed by a Novel 16-kDa VH1-like Phosphatase, VHZ^*

Andres Alonso, Stephen Burkhalter, Joanna Sasin¶, Lutz Tautz, Jori Bogetz, Huong Huynh, Meire C. D. Bremer||, Leslie J. Holsinger||, Adam Godzik¶, and Tomas Mustelin**

From the Program of Signal Transduction, ^¶Program of Bioinformatics, The Burnham Institute, La Jolla, California 92037 and ^||SUGEN Inc., South San Francisco, California 94602

Received for publication, March 27, 2004 , and in revised form, May 25, 2004.

	ABSTRACT

TOP ABSTRACT INTRODUCTION EXPERIMENTAL PROCEDURES RESULTS AND DISCUSSION REFERENCES

 
The smallest active protein-tyrosine phosphatase yet (only 16 kDa) is described here and given the name VHZ for VH1-like member Z because it belongs to the group of small Vaccinia virus VH1-related dual specific phosphatases exemplified by VHR, VHX, and VHY. Human VHZ is remarkably well conserved through evolution as it has species orthologs in frogs, fish, fly, and Archaea. The gene for VHZ, which we designate as DUSP25, is located on human chromosome 1q23.1 and consists of only two coding exons. VHZ is broadly expressed in tissues and cells, including resting blood lymphocytes, Jurkat T cells, HL-60, and RAMOS. In transfected cells, VHZ was located in the cytosol and in other cells also in the nucleoli. Endogenous VHZ showed a similar but more granular distribution. We show that VHZ is an active phosphatase and analyze its structure by computer modeling, which shows that in comparison with the 185-amino acid residue VHR, the 150-residue VHZ is a shortened version of VHR and contains the minimal set of secondary structure elements conserved in all known phosphatases from this class. The surface charge distribution of VHZ differs from that of VHR and is therefore unlikely to dephosphorylate mitogen-activated protein kinases. The remarkably high degree of conservation of VHZ through evolution may indicate a role in some ancient and fundamental physiological process.

	INTRODUCTION

TOP ABSTRACT INTRODUCTION EXPERIMENTAL PROCEDURES RESULTS AND DISCUSSION REFERENCES

 
The VH1-like phosphatases (1) are members of the cysteine-based protein-tyrosine phosphatase (PTP)¹ family and contain the extended consensus signature motif DX_27–30HCX₂GX₂R(S/T/A)X₅A(Y/F)LM or slight variations thereof. The crystal structures of the catalytic domains of the VH1-like enzymes VHR (2), mitogen-activated protein kinase phosphatase-3 (MKP-3) (3), KAP (4), PTEN (5), and MTMR2 (6) show that they have the same topology and catalytic machinery as other members of the Class I cysteine-based PTP family exemplified by PTP1B (7) and RPTP (8). However, whereas the catalytic cleft of most VH1-like phosphatases is only 6 Å deep to allow access by the shorter phosphoamino acid side chains of phosphoserine (Ser(P)) and phosphothreonine (Thr(P)) to the catalytic Cys at the bottom of the pocket, the deeper (9 Å) pocket of classical phosphatases like PTP1B only permits dephosphorylation of phosphotyrosine. On the other hand, the catalytic pockets of PTEN (5) and MTMR2 (6) are considerably wider to accommodate their unique physiological substrate, the lipid-bound inositol ring with phosphate at the D position.

VH1-like phosphatases are found in all main classes of organisms from bacteria to plants, yeast, insects, worms, and mammals. The human and mouse genomes each encode at least 61 VH1-like enzymes², 11 of which are collectively referred to as the MKPs. In addition to a catalytic VH1-like domain, these MKPs contain a non-catalytic CDC25 homology (CH2) domain for docking with mitogen-activated protein kinases (10), which subsequently are dephosphorylated by the catalytic domain. Another group of 19 small VH1-like phosphatases lack the CH2 domain (in both mice and humans),² but some of the phosphatases still dephosphorylate the phosphotyrosine and phosphothreonine residues in the activation loop of mitogen-activated protein kinases in vitro and in cells. In vitro, all of these 30 phosphatases as well as many other VH1-like enzymes dephosphorylate peptides with phosphate on any of three hydroxyl amino acids (serine, threonine, and tyrosine), and they are therefore often referred to as dual specific protein phosphatases (DSPs) (10). The CDC25 phosphatases also show dual specific activity against threonine- and tyrosine-phosphorylated cyclin-dependent protein kinases (11), but they have a different structure and topology (12) and do not share sequence similarity with DSPs apart from the CX₅R motif common to all Cys-based phosphatases. Thus, the three CDC25s are not members of the VH1-like family (as defined above) but apparently became dual specific phosphatases as the result of convergent evolution. In addition, several VH1-like phosphatases dephosphorylate Tyr(P), Ser(P), and Thr(P) in vitro but have non-protein substrates in vivo. For example, phosphatase and tensin homology deleted on chromosome 10, the related phosphatases TPTE and TPIP, and the myotubularins dephosphorylate the Asp-3 phosphate of phosphatidylinositol (13), whereas PIR1 (phosphatase that interacts with RNA/RNP complex 1) (14) and mRNA capping enzyme (RNGTT) dephosphorylate the 5' end of RNA transcripts during the mRNA capping process (14, 15).

Although much of the early work on DSPs focused on the biochemical and structural aspects of these enzymes, more recent work has begun to unravel the physiological functions of DSPs particularly in invertebrates. For example, the puckered (16) and slingshot (17) genes in Drosophila melanogaster and LIP-1 (18) in Caenorhabditis elegans have non-redundant functions revealed by gene deletion. Our understanding of the physiological roles of DSPs in mammals is much more rudimentary. The two reported DSP knock-out mice, MKP-1^-/- (19) and VHX^-/- (20) animals, had no apparent phenotype. However, new functions in cell lines and new substrates have recently been found for DSPs. For example, the cytoskeletal protein ADF/cofilin was identified as the substrate for the slingshot DSPs in the fruit fly D. melanogaster (17), whereas the hYVH1 (DUSP12) DSP was shown to dephosphorylate glucokinase, an enzyme involved in glucose metabolism (21). Another small DSP, laforin (EMP2A), associates via a glycogen-binding domain (22) with glycogen, an interaction that is important for cellular health because mutations in laforin cause a severe human disease, progressive myoclonus epilepsy or Lafora disease (23).

A first step toward understanding the physiological roles and possible redundancies within the DSP group of PTPs is the elucidation of the full repertoire of these enzymes expressed in cells and the characterization of their expression patterns and biochemical properties. Here we begin the characterization of a novel VH1-like phosphatase, which we call VHZ for VH1-like member Z.

	EXPERIMENTAL PROCEDURES

TOP ABSTRACT INTRODUCTION EXPERIMENTAL PROCEDURES RESULTS AND DISCUSSION REFERENCES

 
Antibodies and Reagents—The 9E10 hybridoma producing the monoclonal antibody that recognizes the c-Myc epitope tag was from the American Type Culture Collection (Manassas, VA). Polyclonal rabbit antisera were raised against the recombinant GST fusion protein of full-length VHZ protein and were used at 1:1,000 dilution.

Expression Plasmids for VHZ—The cDNA for VHZ was cloned into the 5' EcoRI to 3' XhoI sites of the pcDNA3.1myc-his vector leaving the epitope tags in the C terminus of the insert.

p-Nitrophenyl Phosphate (pNPP) Dephosphorylation Assay—The hydrolysis of pNPP was assayed at 30 °C for 30 min with 20 µg of enzyme in 100 µl of 0.1 M bis-Tris, pH 6.0, 150 mM NaCl, 1 mM dithiothreitol. The reaction was initiated by the addition of various concentrations of pNPP (ranging from 0.2 to 10 K_m) to the reaction mixtures and terminated by the addition of 200 µl of Biomol reagent. Nonenzymatic hydrolysis of the substrate was corrected by measuring the control without the addition of enzyme. After a 30-min incubation, the absorbance at 620 nm was determined using a PowerWaveX340 microplate spectrophotometer (Bio-Tek Instruments, Inc.) and converted to a molar amount of product using a standard curve. The K_m and K_cat values were determined by fitting the data to the Michaelis-Menten equations using nonlinear regression and the software program GraphPad Prism® (version 4.0).

Cells and Transfections—293T, COS-1, HeLa, and other cell lines were kept at logarithmic growth in RPMI 1640 medium supplemented with 10% fetal calf serum, 2 mM L-glutamine, 1 mM sodium pyruvate, nonessential amino acids, and 100 units/ml each penicillin G and streptomycin. Peripheral blood lymphocytes (80% T cells) were obtained from venous blood from healthy donors (Red Cross Blood Bank, San Diego, CA); Ficoll gradient centrifugation was performed, and monocytes were removed by adherence to plastic at 37 °C for 2 h. 293T and COS-1 cells were transfected with a total of 5–10 µg of DNA by lipofection. Empty vector was added to control samples to make a constant amount of DNA in each sample. Cells were used for experiments 24–48 h after transfection.

Immunoprecipitation, SDS-PAGE, and Immunoblotting—These procedures were performed as before (24–26). Briefly, cells were lysed in 20 mM Tris/HCl, pH 7.5, 150 mM NaCl, 5 mM EDTA containing 1% Nonidet P-40, 1 mM Na₃VO₄, 10 µg/ml aprotinin and leupeptin, 100 µg/ml soybean trypsin inhibitor, and 1 mM phenylmethylsulfonyl fluoride and clarified by centrifugation at 15,000 rpm for 20 min. The clarified lysates were preadsorbed on protein G-Sepharose and then incubated with antibody for 2 h; this was followed by the addition of protein G-Sepharose beads. Immune complexes were washed three times in lysis buffer: once in lysis buffer with 0.5 M NaCl, again in lysis buffer, and then suspended in SDS sample buffer. Proteins resolved by SDS-PAGE were transferred electrophoretically to nitrocellulose filter and were then immunoblotted with 1:1,000 anti-VHZ or optimal dilutions of monoclonal antibodies followed by anti-rabbit or anti-mouse Ig-peroxidase, and the blots were developed by the enhanced chemiluminescence technique (ECL kit, Amersham Biosciences) according to the manufacturer's instructions.

Indirect Immunofluorescence and Confocal Microscopy—Immunofluorescence staining of transfected or endogenous VHZ was performed as described previously (25–28). 293T cells were washed in phosphate-buffered saline, fixed in 3.7% formaldehyde, permeabilized with 0.1% saponin in phosphate-buffered saline, and blocked in 2.5% normal goat serum, 0.1% saponin in phosphate-buffered saline for 30 min at room temperature. Primary and secondary antibody were diluted in the same buffer and incubated with the cells for 1 h each at room temperature. After washing three times with phosphate-buffered saline, the cells were mounted onto glass slides and viewed under a confocal laser scanning microscopy MRC-1024 (Bio-Rad). DNA was stained with TO-PRO-3 iodide (Molecular Probes) at 1:1,000. Nomarski-differential interference contrast images were also taken.

Bioinformatics—A VHZ model was built using a comparative modeling approach based on the structure of the human MAPK phosphatase (Protein Data Bank code 1mkp [PDB] ) and the phosphatase domain of the human cell cycle protein Cdc14 (Protein Data Bank code 1ohe [PDB] ) based on a -fold prediction metaserver alignment (29). Modeling was done by a SWISS-MODEL (30); the same package was used for model visualization. The final model was optimized by the SCRWL program (31). The tree in Fig. 3C was obtained by the STRUCLA server (32) based on several measures of protein structural similarity. Topology diagrams were obtained with the TOPS algorithm (33).

View larger version (38K): [in this window] [in a new window]   FIG. 3. Computer models of the structure of VHZ. A, model of the -helix/-strand fold of VHZ. The phosphate binding loop is shown in red. B, surface topology and charge distribution of VHZ. Blue, positive charge; red, negative charge. C, cladistic tree of the overall structure of several protein, phospholipid, and mRNA phosphatases. The shared core elements are in black; -helices are shown as circles, and -sheets are shown as triangles, the orientation of which indicates if they are parallel or antiparallel. All added elements (-helices, circles; -sheets, triangles) are color coded according to location in the structure. The cladistic tree also illustrates the presumed ancestral structure and six intermediate forms, with "X" over the lost elements.

	RESULTS AND DISCUSSION

TOP ABSTRACT INTRODUCTION EXPERIMENTAL PROCEDURES RESULTS AND DISCUSSION REFERENCES

Apparent species orthologs of VHZ (Fig. 1B) were found in a variety of organisms from mammals (e.g. mouse) to amphibians (Xenopus tropicalis; 68.5% identity, 82.2% similarity), fish (Takifugu rubripes; 64.4% identity, 72.6% similarity), insects (D. melanogaster), and even a possible species ortholog in the Archaea Thermococcus kodakaraensis (NCBI numbers gi:18147126; dbj BAB83049 [GenBank] 1), which is 30.3% identical and 49.7% similar over 145 residues). These sequences indicate that VHZ is a well conserved and ancient gene.

View larger version (79K): [in this window] [in a new window]   FIG. 1. Amino acid sequence and Northern blots for VHZ. A, deduced amino acid sequence of VHZ compared with that of VHX, VHR, and CDC14. Amino acid residues that are identical to those in human VHZ are shaded in gray. B, amino acid sequence comparison between human VHZ and presumed species orthologs from the puffer fish (T. rubripes), frog (X. tropicalis), and the Archaea T. kodakaraensis. Amino acid residues that are identical to those in human VHZ are shaded in gray.

View larger version (55K): [in this window] [in a new window]   FIG. 2. Expression and subcellular location of VHZ. A, Northern blot of mRNA from the indicated tissues with 32P-labeled, full-length VHZ cDNA as probe. B, anti-Myc blot of total lysates of COS cells transfected with empty vector (lane 1), Myc·His-tagged VHY (lane 2) Myc-His-tagged VHZ (lane 3), VHZ-C95S (lane 4), or VHZ-R101M (lane 5). C, anti-VHZ blot of total cell lysates from the indicated cell types or cell lines. D, confocal microscopy of 293T cells transfected with Myc-His-tagged VHZ and stained with the anti-Myc monoclonal antibody 9E10 followed by fluorescein isothiocyanate-conjugated anti-mouse IgG. The white arrows point to staining of the nucleolus. The right column of panels shows Nomarski-differential contrast images of the same cells. E, confocal microscopy of 293T cells stained with the anti-VHZ antibody followed by fluorescein isothiocyanate-conjugated anti-rabbit IgG. The second and fourth panels are Nomarski-differential contrast images of the same cells. The white arrows point to staining of the nucleolus. F, confocal microscopy of HeLa cells triple stained with the anti-VHZ antibody followed by fluorescein isothiocyanate-conjugated anti-rabbit IgG (green), anti-tubulin (red), and with 4'6-diamidino-2-phenylindole for DNA (blue). The fourth column of panels shows merges of the three colors.

To be able to detect the endogenous VHZ protein, we generated an anti-VHZ antiserum by immunizing rabbits with a GST fusion protein containing full-length VHZ. The resulting antisera reacted very well with the expressed tagged VHZ (Fig. 2C, lane 2) and with a protein of 16 kDa in freshly isolated blood lymphocytes, Jurkat T cells, HL-60 myelomonocytic cells, RAMOS B cells, and the tumor cell lines M45 and MT29.

Confocal microscopy of 293T cells transfected with VHZ and stained with the monoclonal antibody against its epitope tag showed that VHZ had a range of subcellular locations (Fig. 2D). In most cells, VHZ was cytoplasmic excluding the nucleus (top panels), whereas in some cells it was found also in the nucleus (second and third row of panels). A minority of cells had VHZ only in the nucleus (bottom panels). Interestingly, in every cell where VHZ was found in the nucleus, the nucleoli were intensely stained. Endogenous VHZ (Fig. 2E) was also primarily located in the cytosol but in a more granular manner with a faint staining of the nucleolus only in some cells (Fig. 2E, white arrows). To determine whether this somewhat variable distribution pattern of VHZ had any correlation to the cell cycle as the 50% homology with CDC14 might suggest, we double stained HeLa cells for endogenous VHZ and DNA and focused on cells in various stages of mitosis (Fig. 2F). In interphase cells, VHZ showed a granular distribution throughout the cytosol. The only change in the location of VHZ during mitosis was its entry into the vicinity of the condensed chromosomes upon breakdown of the nuclear envelope before cytokinesis. In this location, VHZ was more diffusely distributed but not significantly enriched. Staining for tubulin to visualize the mitotic spindle showed that VHZ was in the same region but not organized on the microtubules.

Having established that a 16-kDa VHZ protein exists in cells, we turned to ask if this remarkably small DSP protein is a catalytically active phosphatase. The smallest experimentally verified VH1-like phosphatase so far is the 185-amino acid residue VHR (34), which has been crystallized (2) and found to comprise a catalytic domain with only a few extra residues in its N and C termini. VHZ contains only 150 amino acid residues and is therefore smaller than the catalytic domain of VHR.

A GST fusion protein containing full-length VHZ as well as its C95M and R101M mutant were expressed in Escherichia coli and purified. A standard phosphatase assay with p-nitrophenyl phosphate showed that VHZ readily dephosphorylated this substrate with a K_m of 1.498 mM and a K_cat of 0.0094 s^-1 (Table I). Although the K_m is similar to the values for the small DSPs VH1, VHX, and VHY (Table I), the catalysis rate is slow. Nevertheless, VHZ is an active phosphatase.

A more comprehensive comparison of the predicted structure of VHZ with nine other phosphatases (Fig. 3C) showed that although the central core, which is composed of four parallel -strands (black upside-down triangles) flanked by one and three -helices on each side (black circles), is found in all Cys-based PTPs, many additional elements have been added to this core structure during evolution. These added elements are shown in Fig. 3C as triangles for -sheets and circles for -helices, each color coded according to placement in the overall structure. For example, the classical PTPs (PTP1B, SHP2, and LAR) contain eight -sheets with the four additional ones being both antiparallel (triangles) and parallel (upside-down triangles) to the common four parallel -sheets. They also have additional flanking short -strands and -helices. These features contribute to the deeper catalytic pocket of these classical PTPs, making them strictly tyrosine-specific. In contrast, VHR and VHZ consist essentially only of the common core and thus are close to the likely three-dimensional structure of an archetypal protophosphatase. One could envision an evolutionary sequence of events in which an ancestral Cys-based hydrolase consisting of the minimal essential core of four or five parallel -strands flanked by only one or two -helices on each side was used as a starting point for building a first DSP-like phosphatase, which gave rise to more specialized protein phosphatases and eventually tyrosine-specific PTPs through the addition of more elements. This scenario is supported by the existence of DSP-like enzymes in all kingdoms of life, including Archaea and prokaryotes, whereas "classical" PTPs are found primarily in higher eukaryotes. Interestingly, VHZ appears to be a phylogenetically well conserved enzyme with a probable ortholog even in the Archaea T. kodakaraensis. Thus, it is possible that VHZ represents an ancient stage in the evolution of tyrosine phosphatases. Its presence in the human genome and wide expression in tissues and cell types may indicate that VHZ has retained some important and presumably basic function in cell physiology. On the amino acid sequence level, the closest relatives of VHZ are the CDC14 phosphatases, which are critical regulators of cell division (9). However, the 50% sequence identity with CDC14 is too low for any prediction of VHZ function. This topic will have to be addressed experimentally in the future.

	FOOTNOTES

 
^* This work was supported by a fellowship from the Spanish Ministries of Education and Culture and by National Institutes of Health Grants AI35603, AI48032, AI53585, AI55741, and CA96949 (to T. M.). The costs of publication of this article were defrayed in part by the payment of page charges. This article must therefore be hereby marked "advertisement" in accordance with 18 U.S.C. Section 1734 solely to indicate this fact.

Current address: Universidad de Valladolid, Instituto de Biologia y Genetica Molecular, Facultad de Medicina, c/Ramon y Cajal S/N, 47005 Valladolid, Spain.

^** To whom correspondence should be addressed: The Burnham Institute, 10901 North Torrey Pines Rd., La Jolla, CA 92037. Tel.: 858-713-6270; E-mail: tmustelin{at}burnham-inst.org.

¹ The abbreviations used are: PTP, protein-tyrosine phosphatase; MKP, mitogen-activated protein kinase phosphatase; DSP, dual specific protein phosphatase; GST, glutathione S-transferase; pNPP, p-nitrophenyl phosphate; bis-Tris, 2-[bis(2-hydroxyethyl)amino]-2-(hydroxymethyl)propane-1,3-diol; VHR, VH1 related; VHZ, VH1-like member Z.

² Alonso, A., Sasin, J., Bottini, N., Friedberg, I., Friedberg, I., Osterman, A. Godzik, A., Hunter, T., Dixon, J. E., and Mustelin, T. (2004) Cell 117, 699–711.

³ Alonso, A., Narisawa, S., Bogetz, J., Tautz, L., Hadzik, R., Huynh, H., Williams, S., Gjörloff-Wingren, A., Bremer, M., Holsinger, L., Millan, J., and Mustelin, T. (2004) J. Biol. Chem. 279, 32586–32591.

	REFERENCES

TOP ABSTRACT INTRODUCTION EXPERIMENTAL PROCEDURES RESULTS AND DISCUSSION REFERENCES

 

1. Fauman, E. B., and Saper, M. A. (1996) Trends. Biochem. Sci. 21, 413-417[CrossRef][Medline] [Order article via Infotrieve]
2. Yuvaniyama, J., Denu, J. M., Dixon, J. E., and Saper, M. A. (1996) Science 272, 1328-1331[Abstract]
3. Stewart, A. E., Dowd, S., Keyse, S. M., and McDonald, N. Q. (1999) Nat. Struct. Biol. 6, 174-181[CrossRef][Medline] [Order article via Infotrieve]
4. Hanlon, N., and Barford, D. (1998) Protein Sci. 7, 508-511[Abstract]
5. Lee, J. O., Yang, H., Georgescu, M. M., Di Cristofano, A., Maehama, T., Shi, Y., Dixon, J. E., Pandolfi, P., and Pavletich, N. P. (1999) Cell 99, 323-334[CrossRef][Medline] [Order article via Infotrieve]
6. Begley, M. J., Taylor, G. S., Kim, S.-A., Veine, D. M., Dixon, J. E., and Stuckey, J. A. (2003) Mol. Cell 12, 1391-1402[CrossRef][Medline] [Order article via Infotrieve]
7. Barford, D., Flint, A. J., and Tonks, N. K. (1994) Science 263, 1397-1404[Abstract/Free Full Text]
8. Bilwes, A. M., den Hertog, J., Hunter, T., and Noel, J. P. (1996) Nature 382, 555-559[CrossRef][Medline] [Order article via Infotrieve]
9. Visintin, R., Craig, K., Hwang, E. S., Prinz, S., Tyers, M., and Amon, A. (1998) Mol. Cell 2, 709-718[CrossRef][Medline] [Order article via Infotrieve]
10. Alonso, A., Rojas, A., Godzik, A., and Mustelin, T. (2003) Top. Curr. Genet. 5, 333-358
11. Honda, R., Ohba, Y., Nagata, A., Okayama, H., and Yasuda, H. (1993) FEBS Lett. 318, 331-334[CrossRef][Medline] [Order article via Infotrieve]
12. Fauman, E. B., Cogswell, J. P., Lovejoy, B., Rocque, W. J., Holmes, W., Montana, V. G., Piwnica-Worms, H., Rink, M. J., and Saper, M. A. (1998) Cell 93, 617-625[CrossRef][Medline] [Order article via Infotrieve]
13. Maehama, T., and Dixon, J. E. (1998) J. Biol. Chem. 273, 13375-13378[Abstract/Free Full Text]
14. Deshpande, T., Takagi, T., Hao, L., Buratowski, S., and Charbonneau, H. (1999) J. Biol. Chem. 274, 16590-16594[Abstract/Free Full Text]
15. Takagi, T., Moore, C. R., Diehn, F., and Buratowski, S. (1997) Cell 89, 867-873[CrossRef][Medline] [Order article via Infotrieve]
16. Martin-Blanco, E., Gampel, A., Ring, J., Virdee, K., Kirov, N., Tolkovsky, A. M., and Martinez-Arias, A. (1998) Genes Dev. 12, 557-570[Abstract/Free Full Text]
17. Niwa, R., Nagata-Ohashi, K., Takeichi, M., Mizuno, K., and Uemura, T. (2002) Cell 108, 233-246[CrossRef][Medline] [Order article via Infotrieve]
18. Berset, T., Hoier, E. F., Battu, G., Canevascini, S., and Hajnal, A. (2001) Science 291, 1055-1058[Abstract/Free Full Text]
19. Dorfman, K., Carrasco, D., Gruda, M., Ryan, C., Lira, S. A., and Bravo, R. (1996) Oncogene 13, 925-931[Medline] [Order article via Infotrieve]
20. Chen, A. J., Zhou, G., Juan, T., Colicos, S. M., Cannon, J. P., Cabriera-Hansen, M., Meyer, C. F., Jurecic, R., Copeland, N. G., Gilbert, D. J., Jenkins, N. A., Fletcher, F., Tan, T. H., and Belmont, J. W. (2002) J. Biol. Chem. 277, 36592-36601[Abstract/Free Full Text]
21. Munoz-Alonso, M. J., Guillemain, G., Kassis, N., Girard, J., Burnol, A. F., and Leturque, A. (2000) J. Biol. Chem. 275, 32406-32412[Abstract/Free Full Text]
22. Wang, J., Stuckey, J. A., Wishart, M. J., and Dixon, J. E. (2002) J. Biol. Chem. 277, 2377-2380[Abstract/Free Full Text]
23. Minassian, B. A., Lee, J. R., Herbrick, J. A., Huizenga, J., Soder, S., Mungall, A. J., Dunham, I., Gardner, R., Fong, C. Y., Carpenter, S., Jardim, L., Satishchandra, P., Andermann, E., Snead, O. C., III, Lopes-Cendes, I., Tsui, L. C., Delgado-Escueta, A. V., Rouleau, G. A., and Scherer, S. W. (1998) Nat. Genet. 20, 171-174[CrossRef][Medline] [Order article via Infotrieve]
24. Saxena, M., Williams, S., Taskén, K., and Mustelin, T. (1999) Nat. Cell Biol. 1, 305-311[CrossRef][Medline] [Order article via Infotrieve]
25. Alonso, A., Rahmouni, S., Williams, S., van Stipdonk, M., Jaroszewski, L., Godzik, A., Abraham, R. T., Schoenberger, S. P., and Mustelin, T. (2003) Nat. Immunol. 4, 44-48[CrossRef][Medline] [Order article via Infotrieve]
26. Alonso, A., Bottini, N., Bruckner, S., Rahmouni, S., Williams, S., Schoenberger, S. P., and Mustelin, T. (2004) J. Biol. Chem. 279, 4922-4928[Abstract/Free Full Text]
27. Gjörloff-Wingren, A., Saxena, M., Han, S., Wang, X., Alonso, A., Renedo, M., Oh, P., Williams, S., Schnitzer, J., and Mustelin, T. (2000) Eur. J. Immunol. 30, 2412-2421[CrossRef][Medline] [Order article via Infotrieve]
28. Wang, X., Huynh, H., Gjörloff-Wingren, A., Monosov, E., Stridsberg, M., Fukuda, M., and Mustelin, T. (2002) J. Immunol. 168, 4612-4619[Abstract/Free Full Text]
29. Bujnicki, J. M., Elofsson, A., Fischer, D., and Rychlewski, L. (2001) Bioinformatics 17, 750-751[Abstract/Free Full Text]
30. Schwede, T., Kopp, J., Guex, N., and Peitsch, M. C. (2003) Nucleic Acids Res. 31, 3381-3385[Abstract/Free Full Text]
31. Bower, M. J., Cohen, F. E., and Dunbrack, R. L., Jr. (1997) J. Mol. Biol. 267, 1268-1282[CrossRef][Medline] [Order article via Infotrieve]
32. Sasin, J. M., Kurowski, M. A., and Bujnicki, J. M. (2003) Bioinformatics 19, Suppl. 1, I252-I254[CrossRef][Medline] [Order article via Infotrieve]
33. Michalopoulos, I., Torrance, G. M., Gilbert, D. R., and Westhead, D. R. (2004) Nucleic Acids Res. 32, D251-D254[Abstract/Free Full Text]
34. Ishibashi, T., Bottaro, D. P., Chan, A., Kiki, T., and Aaronson, S. A. (1992) Proc. Natl. Acad. Sci. U. S. A. 89, 12170-12174[Abstract/Free Full Text]
35. Alonso, A., Merlo, J. J., Na, S., Kholod, N., Williams, S., Posada J., and Mustelin, T. (2002) J. Biol. Chem. 277, 5524-5528[Abstract/Free Full Text]
36. Hood, K. L., Tobin, J. F., and Yoon, C. (2002) Biochem. Biophys. Res. Comm. 298, 545-551[CrossRef][Medline] [Order article via Infotrieve]
37. Schumacher, M. A., Todd, J. L., Rice, A. E., Tanner, K. G., and Denu, J. M. (2002) Biochemistry 41, 3009-3017[CrossRef][Medline] [Order article via Infotrieve]

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