Structural and functional analysis of a protein involved in tumour evasion

• Honours

Lung cancer is the biggest cause of cancer deaths globally, where only one out of four patients will live longer than five years. Cancer cells evade our own immune system’s detection through various mechanisms, including downregulating the antigen presentation machinery. This project will structurally and functionally investigate a protein that is involved in the downregulation of MHC-I, whereby identifying critical residues for function may aid in therapeutic development.

The experimental approaches for this project will include introducing mutations into the protein of interest followed by insect cell expression and purification. Further characterisation will include structural characterization with negative stain and cryo-electron microscopy and in parallel functional characterisation with different assays, including ATPase assays.

The end goal will be to use these insights to facilitate a small molecule screen for drug discovery.

The Shakeel laboratory uses a hybrid approach to study the structure and function of multi-protein complexes involved in genome regulation and protection (Tan et al Nature Comms 2025, Shakeel, Rajendra et al Nature 2019; Alcon, Shakeel et al Nature Str Mol Bio 2020, Siljacki et al Nature Str Mol Bio in press).

We in vitro reconstitute activity of these cellular machines to dissect the role of each subunit and built atomic models using single particle cryo-electron microscopy and complementary mass spectrometry methods (native, cross-linking and hydrogen-deuterium exchange). By understanding the structure and mechanisms of these complexes, we will gain insight into the regulation of gene expression and find new targets of intervention when these processes are disrupted.

We are a team of biochemists and structural biologists with 10 years of experience in cryo-electron microscopy and biochemistry.