Oleg Khassan

I joined group of Titia Sixma in September 2025. My research focuses on USP7, a deubiquitinating enzyme which operates at the interface of DNA repair and ubiquitin conjugation.

Given USP7’s involvement in multiple critical pathways and its careful regulation, our goal is to trap selected USP7 states using a mixed biochemical and chemical approach. This is followed by structural biology and interaction proteomics to elucidate how different regulation modes affect USP7 function. This work is significant because haplo-insufficiency of USP7 leads to Hao-Fountain Disease, a severe neurodevelopmental condition.