Cellular Mapping Technique Reveals Protein Locations and Movements

Scientists at the Chan Zuckerberg Biohub San Francisco have developed a novel method called Organelle Profiling to map protein locations within cells. This technique, described in Cell, provides a comprehensive view of how approximately 8,000 different proteins are distributed across 19 cellular compartments.

The method involves tagging cellular compartments, gently breaking open cells, and using mass spectrometry to identify proteins within each compartment. This approach allows researchers to observe proteins at the interfaces between organelles and create a detailed map of protein relationships across the entire cell.

Organelle Profiling's power lies in its ability to track protein movements under different conditions. When applied to cells infected with OC43, a coronavirus causing the common cold, the technique revealed that 633 types of proteins changed locations, while 429 types changed in abundance. Surprisingly, only 54 proteins experienced both types of changes.

This discovery highlights the importance of studying protein location changes, not just abundance, to fully understand cellular responses to stimuli. As senior author Manuel Leonetti noted, "If we want to get the full picture of what's going on in cells during disease, we need to think not only about measuring abundance, but also changes in spatial organization.”

The research team has made their data freely available and plans to offer their tools to the scientific community. They hope this will encourage other researchers to contribute data and help build better models of cellular organization.