Studies of septin complexes using electron microscopy and cryomicroscopy

• Grant number: 24/20432-7
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• Start date: January 01, 2025
• End date: April 30, 2026
• Field of knowledge: Biological Sciences - Biophysics - Molecular Biophysics
• Principal Investigator: Ana Paula Ulian de Araujo
• Grantee: Yuri Volpato Santos
• Host Institution: Instituto de Física de São Carlos (IFSC). Universidade de São Paulo (USP). São Carlos , SP, Brazil
• Associated research grant: 20/02897-1 - Septin filaments: structure, polymerization and role in pathologies, AP.TEM

Abstract

Septins are involved in almost all stages of neuronal development: modulating dendritic morphogenesis and branching, spine morphogenesis and dendrite development, as well as neuronal excitability. In this context, there is still much to be learned about the potential roles of septin monomers, their oligomers and filaments, and structural biology can greatly contribute to this. Our proposal for this PD proposes several structural studies involving septin complexes using electron microscopy (EM) as the main technique. This is because the flexibility of the integral structure of the septin subunits and oligomers seems to be the main cause of the difficulties in crystallizing heterocomplexes or of the low resolution obtained in the eventual crystals obtained. Currently, there is only one resolved structure of a heterocomplex with more than two subunits (SEPT2-6-7), but its low resolution prevents the visualization of important details that would allow more consistent information about the interaction between septins.