Rab7 Associates with Early Endosomes to Mediate Sorting and Transport of Semliki Forest Virus to Late Endosomes
Authors
Affiliations
Semliki forest virus (SFV) is internalized by clathrin-mediated endocytosis, and transported via early endosomes to late endosomes and lysosomes. The intracellular pathway taken by individual fluorescently labeled SFV particles was followed using immunofluorescence in untransfected cells, and by video-enhanced, triple-color fluorescence microscopy in live cells transfected with GFP- and RFP-tagged Rab5, Rab7, Rab4, and Arf1. The viruses progressed from Rab5-positive early endosomes to a population of early endosomes (about 10% of total) that contained both Rab5 and Rab7. SFV were sequestered in the Rab7 domains, and they were sorted away from the early endosomes when these domains detached as separate transport carriers devoid of Rab5, Rab4, EEA1, Arf1, and transferrin. The process was independent of Arf1 and the acidic pH in early endosomes. Nocodazole treatment showed that the release of transport carriers was assisted by microtubules. Expression of constitutively inactive Rab7T22N resulted in accumulation of SFV in early endosomes. We concluded that Rab7 is recruited to early endosomes, where it forms distinct domains that mediate cargo sorting as well as the formation of late-endosome-targeted transport vesicles.
Diesendorf V, La Rocca V, Teutsch M, Alattar H, Obernolte H, Kenst K Cells. 2025; 14(5).
PMID: 40072063 PMC: 11899703. DOI: 10.3390/cells14050334.
Dynamin independent endocytosis is an alternative cell entry mechanism for multiple animal viruses.
Ojha R, Jiang A, Mantyla E, Quirin T, Modhira N, Witte R PLoS Pathog. 2024; 20(11):e1012690.
PMID: 39541404 PMC: 11594517. DOI: 10.1371/journal.ppat.1012690.
Potential Effects of Hyperglycemia on SARS-CoV-2 Entry Mechanisms in Pancreatic Beta Cells.
Michaels T, Essop M, Joseph D Viruses. 2024; 16(8).
PMID: 39205219 PMC: 11358987. DOI: 10.3390/v16081243.
Analyzing the factors affecting virus invasion by quantitative single-particle analysis.
Hou Y, Zhang L, Du L, Fu D, Li J, Liu L Virulence. 2024; 15(1):2367671.
PMID: 38910312 PMC: 11197921. DOI: 10.1080/21505594.2024.2367671.
Therapeutic Applications of Stem Cell-Derived Exosomes.
Abdulmalek O, Husain K, AlKhalifa H, Alturani M, Butler A, Moin A Int J Mol Sci. 2024; 25(6).
PMID: 38542535 PMC: 10971636. DOI: 10.3390/ijms25063562.