Interplay between clathrin and Rab5 controls the early phagocytic trafficking and intracellular survival of Brucella abortus within HeLa cells.
Lipid raft-associated clathrin is essential for host-pathogen interactions during infection. Brucella abortus is an intracellular pathogen that circumvents host defenses, but little is known about the precise infection mechanisms that involve interaction with lipid raft-associated mediators. The aim of this study was to elucidate the clathrin-mediated phagocytic mechanisms of B. abortus. The clathrin dependence of B. abortus infection in HeLa cells was investigated using an infection assay and immunofluorescence microscopy. The redistribution of clathrin in the membrane and in phagosomes was investigated using sucrose gradient fractionation of lipid rafts and the isolation of B. abortus-containing vacuoles, respectively. Clathrin and dynamin were concentrated into lipid rafts during B. abortus infection, and the entry and intracellular survival of B. abortus within HeLa cells were abrogated by clathrin inhibition. Clathrin disruption decreased actin polymerization and the colocalization of B. abortus-containing vacuoles with clathrin and Rab5 but not lysosome-associated membrane protein 1 (LAMP-1). Thus, our data demonstrate that clathrin plays a fundamental role in the entry and intracellular survival of B. abortus via interaction with lipid rafts and actin rearrangement. This process facilitates the early intracellular trafficking of B. abortus to safe replicative vacuoles.
From the College of Veterinary Medicine, Gyeongsang National University, Jinju 660-701, Republic of Korea.
Jin Ju
JJ
Lee
Dae Geun
DG
Kim
Dong Hyeok
DH
Kim
Hannah Leah
HL
Simborio
Wongi
W
Min
Hu Jang
HJ
Lee
Moon
M
Her
Suk Chan
SC
Jung
Masahisa
M
Watarai
Suk
S
Kim
D000199:Actins / Q000737:chemistry; D001692:Biological Transport; D002003:Brucella abortus / Q000502:physiology*; D002966:Clathrin / Q000378:metabolism*; D015971:Gene Expression Regulation, Enzymologic; D006367:HeLa Cells; D006801:Humans; D052118:Lysosomal-Associated Membrane Protein 1 / Q000378:metabolism; D021962:Membrane Microdomains / Q000737:chemistry; D008856:Microscopy, Fluorescence; D010587:Phagocytosis; D010588:Phagosomes / Q000378:metabolism / Q000382:microbiology; D058105:Polymerization; D034741:RNA, Small Interfering / Q000378:metabolism; D020696:rab5 GTP-Binding Proteins / Q000378:metabolism*
D000199:Actins; D002966:Clathrin; D052118:Lysosomal-Associated Membrane Protein 1; D034741:RNA, Small Interfering; D020696:rab5 GTP-Binding Proteins
Bacteria; Bacterial Pathogenesis; Host-Pathogen Interactions; Microbial Pathogenesis; Microbiology