Multivalent Angiomotin-like 1 and Yes-associated protein form a dynamic complex

Area of Science:

• Molecular Biology
• Biophysics
• Cancer Research

Background:

• Yes-associated protein (YAP) is a cancer-promoting co-activator.
• YAP forms multivalent complexes with PPxY motif proteins, influencing cell proliferation.
• Understanding YAP-PPxY complex assembly is limited by challenges in producing full-length binding domains.

Purpose of the Study:

• To produce a functional polypeptide of Angiomotin-like 1 (AMOTL1) containing all three PPxY binding sites.
• To investigate the biophysical mechanisms of YAP-AMOTL1 complex formation.
• To elucidate how these interactions regulate YAP nucleo-cytoplasmic shuttling.

Main Methods:

• Production of a recombinant AMOTL1 polypeptide with three PPxY motifs.
• Biophysical characterization using isothermal titration calorimetry (ITC).
• Size-exclusion chromatography coupled to multi-angle light scattering (SEC-MALS).
• Solution nuclear magnetic resonance (NMR) spectroscopy.

Main Results:

• The AMOTL1 polypeptide is partially disordered.
• AMOTL1 binds YAP WW domains, forming an ensemble of complexes with varying stabilities.
• Binding involves sequential and transient interactions between YAP WW domains and AMOTL1 PPxY motifs.
• A dynamic equilibrium of complexes with two YAP sites bound to two AMOTL1 sites is formed.

Conclusions:

• Transient interactions are key to the rapid assembly and disassembly of YAP-AMOTL1 complexes.
• This dynamic regulation fine-tunes complex stability in response to cellular environment.
• Findings provide insights into YAP regulation and potential therapeutic strategies targeting cancer proliferation.