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Structural characterization of CAS SH3 domain selectivity and regulation reveals new CAS interaction partners

Jakub Gemperle1, Rozálie Hexnerová2, Martin Lepšík2

  • 1Department of Cell Biology, Faculty of Science, Charles University, Vinicna 7, Prague, Czech Republic.

Scientific Reports
|August 16, 2017
PubMed

Insights

Researchers identified the CAS SH3 binding motif, revealing key residues for ligand interaction and regulation. This discovery aids in understanding cancer cell metastasis and identifying new therapeutic targets.

Area of Science:

  • Cellular Biology
  • Molecular Oncology
  • Structural Biology

Background:

  • The Crk-associated substrate (CAS) protein is crucial for cancer cell invasion and metastasis.
  • The CAS SH3 domain mediates signaling, but its ligand binding and regulation mechanisms are poorly understood.

Purpose of the Study:

  • To elucidate the structural basis of CAS SH3 domain ligand binding.
  • To identify the consensus binding motif and regulatory factors of CAS SH3 domain interactions.
  • To discover novel CAS SH3 binding partners.

Main Methods:

  • Structural characterization of the CAS SH3 domain in complex with ligands.
  • Identification of the consensus CAS SH3 binding motif through sequence analysis.
  • Mutation studies to investigate the role of tyrosine 12 phosphorylation.
  • Prediction and experimental validation of novel binding partners.

Main Results:

  • A novel CAS SH3 binding motif was identified, requiring a central lysine at position +2 and optional anchoring residues at position +5.
  • Tyrosine 12 phosphorylation was confirmed to negatively regulate CAS SH3 ligand binding.
  • Two new binding partners, DOK7 and GLIS2, were identified and validated.

Conclusions:

  • The study provides a detailed structural and mechanistic understanding of CAS SH3 domain ligand binding.
  • The findings offer insights into CAS-mediated signaling in cancer progression.
  • The identified binding requirements facilitate the discovery of new protein interactions and potential therapeutic targets.

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