Researchers led by Keren Lasker at Scripps Research, with Ashok Deniz and Raphael Park, used cryo-electron tomography to show that condensates formed by the PopZ protein assemble into ordered filaments that act as a scaffold, shaping the condensate’s properties.

Though conducted in bacteria, the work points to broader relevance for human cells where filament-based condensates clear damaged proteins and regulate growth; disruption of such cleanup condensates is linked to neurodegenerative diseases like ALS, and altered growth-regulating condensates can contribute to cancers such as prostate, breast, and endometrial cancer.

Functional tests using a filament-deficient PopZ mutant revealed condensates became more fluid with lower surface tension, and bacteria expressing the mutant failed to grow and properly segregate DNA, underscoring that condensate architecture and physical properties are essential for cellular life.

Published in Nature Structural and Molecular Biology, the study on February 2, 2026, shows that certain biomolecular condensates harbor an internal filamentous architecture rather than being mere droplets, a finding crucial for their function and opening new therapeutic targeting strategies.

The research points to therapeutic avenues that aim at the internal architecture of condensates, not only their chemistry, to restore proper structure and function and treat related diseases.

Single-molecule FRET data indicate PopZ adopts different conformations depending on whether it is outside or inside a condensate, revealing location-dependent structural states that influence function.

Key contributors include Keren Lasker, Daniel Scholl, Ashok Deniz, Raphael Park, Tumara Boyd, Andrew P. Latham, Alexandra Salazar, Asma Khan, Steven Boeynaems, Alex S. Holehouse, Gabriel C. Lander, and Andrej Sali, with support from NIH, NSF, and various foundations.