How local pressure pushes the cell membrane outward
How can a crowded patch inside a cell create a temporary bulge?
How it works
Cells sometimes form small balloon-like bulges on their surface, called blebs. A bulge can appear when the membrane loosens from the supporting layer beneath it and pressure pushes the membrane outward.
Water movement may help these bulges grow. A 2026 study showed that many proteins assembling around CaMKII can create a local difference in osmotic pressure, contributing to membrane expansion.
CaMKII is usually known as an enzyme that chemically regulates other proteins. This study highlights another possibility: assembling many proteins in one place can itself affect water movement and cell shape.
What we want to learn next
Published researchWe aim to connect the amount of protein assembly and water movement to the size and growth rate of blebs. This does not mean that bleb formation has been shown to use the same phase-separation mechanism as p62 or OPTN droplets.
Related publications & press releases
A protein assembly can generate local osmotic effects that drive outward protrusions of the cell membrane.