The role of biomolecular protein condensates in cuticle deposition
The arthropod cuticle or apical ECM (aECM) is a remarkable multifunctional composite material made of chitin nanofibers embedded in a protein matrix. Cuticular proteins (CPs) occupy a large portion of the material and play a crucial role in determining the optical and mechanical properties of the cuticle. However, it is unclear how they are introduced into chitin mesh. Protein condensation was hypothesized to play a role in the formation of aECM. This hypothesis is further supported by our recent finding that a large group of CPs from the spider Cupiennius salei contain large intrinsically disordered regions (IDR) with simple sequence composition similar to prion-like proteins. The aim of this project is to systematically survey CPs for their ability to form condensates in vivo and in vitro and to test how protein condensation affects chitin-protein composite assembly.