Abstract
Tau protein in vitro can undergo liquid-liquid phase separation (LLPS); however, observations of this phase transition in living cells are limited. To investigate protein state transitions in living cells, we attached Cry2 to Tau and studied the contribution of each domain that drives the Tau cluster in living cells. Surprisingly, the proline-rich domain (PRD), not the microtubule binding domain (MTBD), drives LLPS and does so under the control of its phosphorylation state. Readily observable, PRDderived cytoplasmic condensates underwent fusion and fluorescence recovery after photobleaching consistent with the PRD LLPS in vitro. Simulations demonstrated that the charge properties of the PRD predicted phase separation. Tau PRD formed heterotypic condensates with EB1, a regulator of plus-end microtubule dynamic instability. The specific domain properties of the MTBD and PRD serve distinct but mutually complementary roles that use LLPS in a cellular context to implement emergent functionalities that scale their relationship from binding α-beta tubulin heterodimers to the larger proportions of microtubules.
| Original language | English (US) |
|---|---|
| Article number | e202006054 |
| Journal | Journal of Cell Biology |
| Volume | 219 |
| Issue number | 11 |
| DOIs | |
| State | Published - 2020 |
Funding
This study was funded by U54 NS (100717; K.S. Kosik), the Tau Consortium (K.S. Kosik and S. Han), the Dr. Miriam and Sheldon G. Adelson Medical Research Foundation (K.S. Kosik and, M.Z. Wilson), the Larry L. Hillblom Foundation (K.S. Kosik), the Edward N. and Della L. Thome Memorial Foundation (K.S. Kosik), and the National Institutes of Health (R01AG056058; K.S. Kosik, S. Han, J. Shea, and J. McCarty). G.H. Fredrickson and J. Shea acknowledge the Materials Research Science and Engineering Centers Program of the National Science Foundation (DMR 1720256), and J. Shea acknowledges the National Science Foundation (MCB-1716956). The computational part of this research used resources of the Extreme Science and Engineering Discovery Environment (supported by National Science Foundation Project TG-MCA05S027 and the Center for Scientific Computing from the California NanoSystems Institute, University of California, Santa Barbara, available through the Materials Research Laboratory; the National Science Foundation Materials Research Science and Engineering Centers (DMR-1720256) and the National Science Foundation (CNS-1725797). We acknowledge the use of the Neuroscience Research Institute, Molecular, Cell and Developmental Biology Microscopy Facility, and the Resonant Scanning Confocal Microscope supported by the National Science Foundation Major Research Instrumentation Program (DBI-1625770). The authors declare no competing financial interests.
ASJC Scopus subject areas
- Cell Biology