Ectopic reconstitution of a spine-apparatus-like structure provides insight into mechanisms underlying its formation.

ABSTRACT: The endoplasmic reticulum (ER) is a continuous cellular endomembrane network that displays focal specializations. Most notable examples of such specializations include the spine apparatus of neuronal dendrites and the cisternal organelle of axonal initial segments. Both organelles exhibit stacks of smooth ER sheets with a narrow lumen, interconnected by a dense protein matrix. The actin-binding protein synaptopodin is required for their formation, but the underlying mechanisms remain unknown. Here, we report that the spine apparatus and synaptopodin are conserved from flies to mammals and that a highly conserved region of this protein is necessary, but not sufficient, for its association with ER. We reveal a dual role of synaptopodin in generating actin bundles and in linking them to the E

SUBMITTER: Falahati H 

PROVIDER: S-EPMC11753949 | biostudies-literature | 2025 Jan

REPOSITORIES: biostudies-literature