Remote conformational control of a molecular switch via methylation and deprotonation

Methylation and deprotonation at remote sites of a diphenylacetylene-based molecular switch exert global conformational changes through subtle tuning of a hydrogen-bonding network.

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Structural Insights into the Active Site Formation of DUSP22 in N-loop-containing Protein Tyrosine Phosphatases

International Journal of Molecular Sciences ◽

10.3390/ijms21207515 ◽

2020 ◽

Vol 21 (20) ◽

pp. 7515

Author(s):

Chih-Hsuan Lai ◽

Co-Chih Chang ◽

Huai-Chia Chuang ◽

Tse-Hua Tan ◽

Ping-Chiang Lyu

Keyword(s):

Hydrogen Bonding ◽

Phosphatase Activity ◽

Conformational Changes ◽

Active Site ◽

Protein Tyrosine Phosphatases ◽

Site Formation ◽

Tyrosine Phosphatases ◽

Conserved Residues ◽

Protein Tyrosine ◽

Hydrogen Bonding Network

Cysteine-based protein tyrosine phosphatases (Cys-based PTPs) perform dephosphorylation to regulate signaling pathways in cellular responses. The hydrogen bonding network in their active site plays an important conformational role and supports the phosphatase activity. Nearly half of dual-specificity phosphatases (DUSPs) use three conserved residues, including aspartate in the D-loop, serine in the P-loop, and asparagine in the N-loop, to form the hydrogen bonding network, the D-, P-, N-triloop interaction (DPN–triloop interaction). In this study, DUSP22 is used to investigate the importance of the DPN–triloop interaction in active site formation. Alanine mutations and somatic mutations of the conserved residues, D57, S93, and N128 substantially decrease catalytic efficiency (kcat/KM) by more than 102-fold. Structural studies by NMR and crystallography reveal that each residue can perturb the three loops and induce conformational changes, indicating that the hydrogen bonding network aligns the residues in the correct positions for substrate interaction and catalysis. Studying the DPN–triloop interaction reveals the mechanism maintaining phosphatase activity in N-loop-containing PTPs and provides a foundation for further investigation of active site formation in different members of this protein class.

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Faculty Opinions recommendation of Structural and kinetic evidence for an extended hydrogen-bonding network in catalysis of methyl group transfer. Role of an active site asparagine residue in activation of methyl transfer by methyltransferases.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.1067744.520660 ◽

2007 ◽

Author(s):

Rowena Matthews

Keyword(s):

Hydrogen Bonding ◽

Active Site ◽

Methyl Group ◽

Group Transfer ◽

Methyl Transfer ◽

Hydrogen Bonding Network ◽

Asparagine Residue ◽

Methyl Group Transfer

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Structural studies of phosphorylation-dependent interactions between the V2R receptor and arrestin-2

Nature Communications ◽

10.1038/s41467-021-22731-x ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Qing-Tao He ◽

Peng Xiao ◽

Shen-Ming Huang ◽

Ying-Li Jia ◽

Zhong-Liang Zhu ◽

...

Keyword(s):

Crystal Structures ◽

Conformational Changes ◽

Nmr Spectrum ◽

H Nmr ◽

Interaction Sites ◽

Receptor Interactions ◽

Remote Sites ◽

Genetic Code Expansion ◽

G Protein Coupled ◽

Interaction Change

AbstractArrestins recognize different receptor phosphorylation patterns and convert this information to selective arrestin functions to expand the functional diversity of the G protein-coupled receptor (GPCR) superfamilies. However, the principles governing arrestin-phospho-receptor interactions, as well as the contribution of each single phospho-interaction to selective arrestin structural and functional states, are undefined. Here, we determined the crystal structures of arrestin2 in complex with four different phosphopeptides derived from the vasopressin receptor-2 (V2R) C-tail. A comparison of these four crystal structures with previously solved Arrestin2 structures demonstrated that a single phospho-interaction change results in measurable conformational changes at remote sites in the complex. This conformational bias introduced by specific phosphorylation patterns was further inspected by FRET and 1H NMR spectrum analysis facilitated via genetic code expansion. Moreover, an interdependent phospho-binding mechanism of phospho-receptor-arrestin interactions between different phospho-interaction sites was unexpectedly revealed. Taken together, our results provide evidence showing that phospho-interaction changes at different arrestin sites can elicit changes in affinity and structural states at remote sites, which correlate with selective arrestin functions.

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