RPTPα phosphatase activity is allosterically regulated by the membrane-distal catalytic domain
| Autor: | Kuninobu Wakabayashi, Nunzio Bottini, Mattias Svensson, Yutao Wen, Stephanie M. Stanford, Eugenio Santelli, Shen Yang |
|---|---|
| Rok vydání: | 2020 |
| Předmět: |
Models
Molecular 0301 basic medicine animal structures Protein Conformation Phosphatase Allosteric regulation Sequence Homology Protein tyrosine phosphatase Crystallography X-Ray Biochemistry 03 medical and health sciences Protein structure Allosteric Regulation Catalytic Domain Humans Amino Acid Sequence Molecular Biology 030102 biochemistry & molecular biology Chemistry Receptor-Like Protein Tyrosine Phosphatases Class 4 Cell Membrane HEK 293 cells Cell Biology Cell biology Transmembrane domain 030104 developmental biology Protein Structure and Folding Protein Tyrosine Phosphatases Signal transduction Protein Binding Proto-oncogene tyrosine-protein kinase Src |
| Zdroj: | J Biol Chem |
| ISSN: | 0021-9258 |
| DOI: | 10.1074/jbc.ra119.011808 |
| Popis: | Receptor-type protein tyrosine phosphatase α (RPTPα) is an important positive regulator of SRC kinase activation and a known promoter of cancer growth, fibrosis, and arthritis. The domain structure of RPTPs comprises an extracellular region, a transmembrane helix, and two tandem intracellular catalytic domains referred to as D1 and D2. The D2 domain of RPTPs is believed to mostly play a regulatory function; however, no regulatory model has been established for RPTPα-D2 or other RPTP-D2 domains. Here, we solved the 1.8 Å resolution crystal structure of the cytoplasmic region of RPTPα, encompassing D1 and D2, trapped in a conformation that revealed a possible mechanism through which D2 can allosterically inhibit D1 activity. Using a D2-truncation RPTPα variant and mutational analysis of the D1/D2 interfaces, we show that D2 inhibits RPTPα phosphatase activity and identified a (405)PFTP(408) motif in D1 that mediates the inhibitory effect of D2. Expression of the gain-of-function F406A/T407A RPTPα variant in HEK293T cells enhanced SRC activation, supporting the relevance of our proposed D2-mediated regulation mechanism in cell signaling. There is emerging interest in the development of allosteric inhibitors of RPTPs but a scarcity of validated allosteric sites for RPTPs. The results of our study not only shed light on the regulatory role of RPTP-D2 domains, but also provide a potentially useful tool for the discovery of chemical probes targeting RPTPα and other RPTPs. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|