| Autor: |
Kemble GW; Department of Pharmacology, University of California, San Francisco 94143-0450., Danieli T, White JM |
| Jazyk: |
angličtina |
| Zdroj: |
Cell [Cell] 1994 Jan 28; Vol. 76 (2), pp. 383-91. |
| DOI: |
10.1016/0092-8674(94)90344-1 |
| Abstrakt: |
It has been proposed that membrane fusion events such as virus-cell fusion proceed through a hemifusion intermediate, a state where lipids but not contents of the fusing compartments mix. We engineered the influenza hemagglutinin (HA) such that it would be anchored in membranes via a glycosylphosphatidylinositol (GPI) tail. GPI-anchored HA forms a trimer that can bind red blood cells (RBCs) and change conformation under fusion-inducing conditions. Using RBCs labeled with fluorescent lipid or fluorescent soluble content probes, we found that GPI-anchored HA mediated lipid mixing with similar time course and efficiency as wt-HA, yet did not mediate transfer of soluble contents. Hence, GPI-anchored HA appears to initiate, but not complete, a fusion reaction. We interpret our results as evidence for uncoupling a physiological fusion reaction, for trapping a hemifusion intermediate, and for assigning a role to a transmembrane domain in a fusion event. |
| Databáze: |
MEDLINE |
| Externí odkaz: |
|
