4GRZ

Crystal structure of SHP1 catalytic domain with PO4

Summary for 4GRZ

• Entry DOI: 10.2210/pdb4grz/pdb
• Descriptor: Tyrosine-protein phosphatase non-receptor type 6, PHOSPHATE ION (3 entities in total)
• Functional Keywords: phosphatase domain, hydrolase
• Biological source: Homo sapiens (human)
• Cellular location: Cytoplasm: P29350
• Total number of polymer chains: 1
• Total formula weight: 33013.09

Authors

Alicea-Velazquez, N.L.,Jakoncic, J.,Boggon, T.J. (deposition date: 2012-08-27, release date: 2012-12-19, Last modification date: 2023-09-13)

Primary citation

Alicea-Velazquez, N.L.,Jakoncic, J.,Boggon, T.J.
Structure-guided studies of the SHP-1/JAK1 interaction provide new insights into phosphatase catalytic domain substrate recognition.
J.Struct.Biol., 181:243-251, 2013

PubMed Abstract: SHP-1 (PTPN6) is a member of the SHP sub-family of protein tyrosine phosphatases and plays a critical role in the regulation of the JAK/STAT signaling pathway. Previous studies suggested that SHP-1 contains a PTP1B-like second phosphotyrosine pocket that allows for binding of tandem phosphotyrosine residues, such as those found in the activation loop of JAK kinases. To discover the structural nature of the interaction between SHP-1 and the JAK family member, JAK1, we determined the 1.8Å co-crystal structure of the SHP-1 catalytic domain and a JAK1-derived substrate peptide. This structure reveals electron density for only one bound phosphotyrosine residue. To investigate the role of the predicted second site pocket we determined the structures of SHP-1 in complex with phosphate and sulfate to 1.37Å and 1.7Å, respectively, and performed anomalous scattering experiments for a selenate-soaked crystal. These crystallographic data suggest that SHP-1 does not contain a PTP1B-like second site pocket. This conclusion is further supported by analysis of the relative dephosphorylation and binding affinities of mono- and tandem-phosphorylated peptide substrates. The crystal structures instead indicate that SHP-1 contains an extended C-terminal helix α2' incompatible with the predicted second phosphotyrosine binding site. This study suggests that SHP-1 defines a new category of PTP1B-like protein tyrosine phosphatases with a hindered second phosphotyrosine pocket.

PubMed: 23296072
DOI: 10.1016/j.jsb.2012.12.009

Experimental method

X-RAY DIFFRACTION (1.3732 Å)