Mapping Protein Shape-Shifting with AI
Juan Vanegas, associate professor of biochemistry and biophysics, is using AlphaFold and related AI methods to explore how membrane proteins shift between different shapes and functional states.
His lab focuses on membrane proteins, which make up roughly 30% of all proteins and carry out essential roles in cells, including sensing environmental changes and supporting processes like vascular development and osmotic regulation. Many of these proteins are mechanosensitive, meaning they respond to physical force, but their structures are difficult to capture experimentally or computationally because they move between multiple conformations.
To study them, Vanegas has traditionally relied on molecular dynamics simulations, which use physics-based models to simulate atomic motion. While highly accurate, these simulations are extremely computationally expensive, sometimes taking days or weeks on supercomputers for a single protein system.
More recently, his lab has turned to data-driven approaches like AlphaFold, which was trained on large structural and genetic databases. Rather than generating just one predicted protein shape, Vanegas and his team are adapting the model to explore the different shapes a protein might naturally take. By making small changes to the information they provide the model, they can uncover a wide range of biologically realistic possibilities.
In some cases, these AI-generated conformations align with results from experimental structures and molecular dynamics simulations, suggesting the models are capturing physically meaningful behavior. Importantly, the approach is far less computationally intensive, producing results in minutes rather than days.
However, Vanegas noted limitations. The methods can behave like a black box, are difficult to control under specific environmental conditions and can be inconsistent depending on how closely a protein resembles training data.
Even so, he sees promise in using AI to better understand protein dynamics. The long-term goal is to move beyond simulating individual structures and instead using sequence information to predict the full range of shapes a protein can adopt, reducing or even replacing the need for costly simulations.