Protein Tyrosine Phosphatases: Structure, regulation and biological function

Protein Tyrosine Phosphatases: Structure, regulation and biological function 2007 - 2011
Acronym: PTPNET
Project director: Stefan Szedlacsek
Grant agreement ID: 35830
External website: full link

Project Funded under: Human resources and Mobility in the specific programme for research, technological development and demonstration "Structuring the European Research Area" under the Sixth Framework Programme 2002-2006. PTPNET is a training network for young scientists in the field of protein tyrosine phosphatase (PTP) research.

PTPs are protein with enzymatic properties and a range of cellular and tissue functions. PTPs participate in the control of embryo development and normal physiology in humans, while PTPs are also causative for  a number of diseases. However, general knoledge of PTP function lags far behind that of many other proteins, and thus PTPNET was established to adress many pressing questions in the field.

These included the Consortium's desire to understand protein structure and regulation, how PTPs send inside cells and tissues, and how PTPs are involved in embryonic development and diseases such as cancer, multiple sclerosis and osteoporosis.


Stefan Szedlacsek, Dr.
Stefan Szedlacsek, Dr.

Head of Department

Professor Dr. Stefan Eugen Szedlacsek is the Head of the Enzymology Department at the Institute of Biochemistry of the Romanian Academy. He holds a PhD degree in Biotechnology from Polytechnic University of Bucharest as well as a MSc in Organic Synthesis (Polytechnic University- Bucharest) and MSc in Mathematics (Bucharest University). As a visiting scientist, he performed research in the field of cholesterol metabolism University of Illinois at Urbana-Champaign (USA), where he succeeded to evidence a new pathway in the metabolism of oxysterols. He is an “Alexander von Humboldt“ fellow and worked in Germany, in the Institute of Biochemistry (Kiel University) More...

The network proposed in this project has scientific, technological and training objectives. She set out to rapidly define PTP structures, substrates, and ligands, and to define the signaling output of PTPs. Also, project proposed to follow how this relates to the involvement of PTPs in the etiology and progression of human disease. This knowledge will ultimately be exploited in the development of therapies targeting PTP enzymes.

The PTP domain is relatively small and geographically fragmented and a key objective is to bring together groups from Europe and Associated States to provide a highly interactive, interdisciplinary and cross-sectoral network.


This network will be based on the principle of effective training for EU-funded researchers and will provide a unique training platform that will increase critical mass, collaboration and best practice in this field.

1.Project Coordinator: Dr.Andrew Stoker

University College London
Reader in Developmental Neurobiology
Neural Development Unit Institute of Child Health
30 Guilford Street; London WC1N 1EH; UK

Partner 2: Professor Rafael Pulido 

Fundacion de la Comunidad Valenciana Centro de Investigation Principe Felipe 
Adress: C/ d'Eduardo Primo Yúfera, 3,
Bloque C, Planta 3, 4; 6012; Valencia, Spain

Partner 3: Professor Arne Östman

Karolinska Institute,Stockholm 
Dept of Oncology-Pathology  
Solnavägen 1, 171 77 Solna, Sweden

Partner 4: Professor: Szedlacsek Stefan 

Institute of Biochemistry  of the  Romanian Academy
Department of Enzymology  
Bucharest, Romania
Splaiul Independenței nr.296,
Sector 6

Partner 5: Professor: Frank D Böhmer

Center for Molecular Biomedicine, JENA,
Hans-Knöll-Straße 2, 07745 Jena, Germany

Partner 6: Professor:Jeroen den Hertog 


Hubrecht Institute, Utrecht,
Uppsalalaan 8, 3584 CT Utrecht, Netherlands

Partner 7: Primary Investigator: Sheila Harroch

Pasteur Institute, Paris
25-28 Rue du Dr Roux, 75015 Paris, France

Partner 8: Professor: Wiljan J. A. J. Hendriks

Radboud Univ. Nijmegen Medical Centre, Nijmegen,             

Department of Cell Biology,
Geert Grooteplein Zuid 10, 6525
GA Nijmegen, Netherlands

Partner 9: Associate Director: Rob Hooft van Huijsduijnen 

Merck Serono, Geneva                          

Quai des Bergues 29, 1201 Genève, Switzerland

Partner 10: Professor: Lydia Tabernero

Division of Evolution, Infection and Genomics
Oxford Rd, Manchester M13 9PL, United Kingdom

Partner 11: Professor: Ari Elson


Department of Molecular Genetics
Rehovot 76100; Israel

Partner 12: Professor: E. Yvonne Jones

The Chancellor, Masters and Scholars of the University of  Oxford;  

Division of Structural Biology
OX3 7BN; United Kingdom

Group leader:Dr.Stefan Szedlacsek

Postdoctoral fellow:Dr.Mihaela BĂLAȘU

ESR trainee:Sujay Turuvekere Mallikarjuna,

PhD Student:Rodica BADEA

PhD student:Georgiana PETRĂREANU

PhD student:Mihaela MENȚEL  

1. Progress in cross interaction among disciplines:

    2.  Access to/use of state-of-the-art infrastructure and facilities:

1      3. Education and completion of doctoral studies:



       4.  Other additional information

  ·         Teams in Sweden and Germany studied how chemicals known as reactive oxygen species (ROS) can control PTPs. ROS are produced under many disease conditions including cancer and neurodegeneration

·         French team discovered the role for a PTP in cells that make myelin - the "insulator" of nerve fibres. Myelin is damaged in multiple sclerosis and there is great interest in developing ways to repair it 

·         Swiss industrial team also researched multiple sclerosis and documented several new PTPs as potential therapeutic targets. This work thus provided important new knowledge with translational potential

·         Other teams discovered new roles for PTPs in both brain tumours and leukaemia, and a Dutch team completed the first ever screen of PTP gene function in zebrafish

·         Finally, Manchester team successfully delivered the web resource PhosphaBase, a publically accessible database and research platform for studying PTPs across hundreds of organisms. This is a major success for the Network,leaving a positive and lasting legacy.




I. Experimental

  • Both the full-length hEya3 gene and the C-terminal domain of hEya3(ED) were cloned using a cDNA library;
  • The experiments using the phosphorylated peptides could not demonstrate that hEya3 protein can autodephosphorilate at the sites we proposed;
  • The enzymatic activity measured for both hEya3 full-length and hEya3ED on pNPP revealed that N-terminal domain of hEya3 has no influences on its phosphates activity;
  • A big difference was observed when the enzymatic activity was measured on DiFMUP. The hEya3(ED) didn’t exhibit any activity, possible because of the lack of the native conformation;
  • We report for the first time that a full-length Eye-absent protein exhibits enzymatic activity. hEya1 activity appears to be, in preliminary assays, inhibited by high concentration of pNPP;
  • Investigating PLCγ2 as a potential substrate of RPTPμ, protein pull-down experiments with a series of mutant forms of RPTPm confirmed that these two proteins interact and can be efficiently co-precipitated from cells;
  • The catalytic domain of RPTPμ has been shown to dephosphorylate both the pY753 and pY759 sites of PLCγ2, which may have physiological significance because these residues are involved in activation of PLCγ2. The data strongly suggest that PLCγ2 is a bona fide substrate of RPTPμ.


II. Organization of workshops/courses:

Institute of Biochemistry (IBI) organized the FEBS Advanced Course "Recombinant DNA Technology and Protein Expression" held in Bucharest between September 7-14,2008. The ESR from the Institute of Biochemistry (Partner #4) and a member of the team from Jena University Hospital (Partner #4) attended this practical and theoretical course.

III. Relevant training for the ESR trainee (Sujay Turuvekere Mallikarjuna):

a) Participation and presentation of research results in the PTPNET meeting held in Manchester, between June 13-18, 2008

b) Participation in training course “Bioinformatics and Crystallography Workshop” held in Manchester between June 13-18, 2008 and in the FEBS Advanced Course "Recombinant DNA Technology and Protein Expression" held in Bucharest, bewteen June 13-18, 2008

c) Secondment in University of Oxford (Partner #10), between July 1- July, 31 (2008)



Published papers:

1.Protein tyrosine phosphatases: structure-function relatuionships; authors: Tabernero, L., A. R. Aricescu, E. Y. Jones, and S. E. Szedlacsek.; Volume 275; Issue 5; Page 867-882; DOI10.1111/j.1742-4658.2008.06251.x; Febs Journal; 2008

2.Interface analysis of the complex between ERK2 and PTP-SL; authors: Balasu MC, Spiridon LN, Miron S, Craescu CT, Scheidig AJ, Petrescu AJ, Szedlacsek SE.;; Volume 4; Issue 5; DOI10.1371/journal.pone.0005432; Plos One; 2009

3.Large scale  mammalian  expression and purification of protein tyrosine phosphatase PTPBR7; authors: Sujay Turuvekere Mallikarjuna, Stefan E. Szedlacsek*; ROM.J.BIOCHEM., 49, 1, 13–20; 2012.

4.Protein tyrosine phosphatase structure-function relationships in regulation and pathogenesis; authors: Bohmer, F., Szedlacsek, S., Tabernero, L., Ostman, A., den Hertog, J;; Volume 280, Issue 2, Page: 413-431; DOI10.1111/j.1742-4658.2012.08655.x1; Febs Journal; 2013

Book Chapter:

1.Expression, Purification, and Kinetic Analysis of PTP Domains; authors: Mentel, M; Badea, RA; Necula-Petrareanu, G; Mallikarjuna, ST; Ionescu, AE; Szedlacsek, SE;; Book Series Methods in Molecular Biology; Volume1447; Page39-66; DOI10.1007/978-1-4939-3746-2_3; 2016;

Conferences, poster presentations, seminars, workshop