title: Peroxisomes, lipid droplets, and endoplasmic reticulum "hitchhike" on motile early endosomes.
abstract: Intracellular transport is mediated by molecular motors that bind cargo to be transported along the cytoskeleton. Here, we report, for the first time, that peroxisomes (POs), lipid droplets (LDs), and the endoplasmic reticulum (ER) rely on early endosomes (EEs) for intracellular movement in a fungal model system. We show that POs undergo kinesin-3- and dynein-dependent transport along microtubules. Surprisingly, kinesin-3 does not colocalize with POs. Instead, the motor moves EEs that drag the POs through the cell. PO motility is abolished when EE motility is blocked in various mutants. Most LD and ER motility also depends on EE motility, whereas mitochondria move independently of EEs. Covisualization studies show that EE-mediated ER motility is not required for PO or LD movement, suggesting that the organelles interact with EEs independently. In the absence of EE motility, POs and LDs cluster at the growing tip, whereas ER is partially retracted to subapical regions. Collectively, our results show that moving EEs interact transiently with other organelles, thereby mediating their directed transport and distribution in the cell.
authors.affiliation: Biosciences, University of Exeter, Exeter EX4 4QD, England, UK.
authors.forename: Sofia C
authors.initials: SC
authors.lastname: Guimaraes
authors.affiliation: Biosciences, University of Exeter, Exeter EX4 4QD, England, UK.
authors.forename: Martin
authors.initials: M
authors.lastname: Schuster
authors.affiliation: Biosciences, University of Exeter, Exeter EX4 4QD, England, UK.
authors.forename: Ewa
authors.initials: E
authors.lastname: Bielska
authors.affiliation: Biosciences, University of Exeter, Exeter EX4 4QD, England, UK.
authors.forename: Gulay
authors.initials: G
authors.lastname: Dagdas
authors.affiliation: Biosciences, University of Exeter, Exeter EX4 4QD, England, UK.
authors.forename: Sreedhar
authors.initials: S
authors.lastname: Kilaru
authors.affiliation: Biosciences, University of Exeter, Exeter EX4 4QD, England, UK.
authors.forename: Ben R A
authors.initials: BR
authors.lastname: Meadows
authors.affiliation: Biosciences, University of Exeter, Exeter EX4 4QD, England, UK.
authors.forename: Michael
authors.initials: M
authors.lastname: Schrader
authors.affiliation: Biosciences, University of Exeter, Exeter EX4 4QD, England, UK g.steinberg@exeter.ac.uk.
authors.forename: Gero
authors.initials: G
authors.lastname: Steinberg
mesh_terms: D003599:Cytoskeleton / Q000378:metabolism*; D004398:Dyneins / Q000378:metabolism; D004721:Endoplasmic Reticulum / Q000378:metabolism*; D011992:Endosomes / Q000378:metabolism*; D049452:Green Fluorescent Proteins / Q000737:chemistry; D016547:Kinesins / Q000378:metabolism; D066292:Lipid Droplets / Q000378:metabolism*; D008055:Lipids / Q000737:chemistry; D008870:Microtubules / Q000378:metabolism; D008928:Mitochondria / Q000378:metabolism; D008969:Molecular Sequence Data; D009154:Mutation; D020675:Peroxisomes / Q000378:metabolism*; D021381:Protein Transport; D012441:Saccharomyces cerevisiae; D014588:Ustilago
chemical_list: D008055:Lipids; D049452:Green Fluorescent Proteins; D004398:Dyneins; D016547:Kinesins