Researchers used an image-based screen to identify structural features in amphipathic helices that govern their association with the inner nuclear membrane, according to a peer-reviewed study published in Nature Communications on July 30, 2026. The findings show that binding to the inner nuclear membrane depends primarily on how sensitive an amphipathic helix is to lipid packing defects, accompanied by a minor electrostatic contribution.
The study examined how different amphipathic helices behave when directed into the cell nucleus. Amphipathic helices that normally localize to endoplasmic reticulum or Golgi membranes successfully associated with the inner nuclear membrane upon nuclear targeting. In contrast, helices targeting mitochondria remained largely dissolved in the nucleoplasm. However, when researchers mutated a mitochondrial helix to increase its preference for membranes with lipid packing defects, the modified helix bound to the inner nuclear membrane once targeted to the nucleus.
Structural and Mechanical Effects
Structural analysis focused on TMEM214, an inner nuclear membrane-associated protein. The researchers observed that an amphipathic helix within TMEM214 folds upon binding to lipid packing defects, while the full-length TMEM214 protein localizes to nuclear pores.
The team also evaluated mechanical influences on membrane binding. Nuclear swelling increased the association of select amphipathic helices with the inner nuclear membrane, whereas stretching the cell did not yield the same effect.
The research was conducted by scientists at Yale University, the Institute for Bioengineering of Catalonia, the Barcelona Institute of Technology, the University of Fribourg, and the Universitat de Barcelona. Funding came from the National Institutes of Health, the Swiss National Science Foundation, the European Research Council, the Spanish Ministry of Science and Innovation, and the Generalitat de Catalunya.
