The Salmonella effector protein PipB2 is a linker for kinesin-1.
Understanding the mechanisms of Salmonella virulence is an important challenge. The capacity of this intracellular bacterial pathogen to cause diseases depends on the expression of virulence factors including the second type III secretion system (TTSS-2), which is used to translocate into the eukaryotic cytosol a set of effector proteins that divert the biology of the host cell and shape the bacterial replicative niche. Yet little is known about the eukaryotic functions affected by individual Salmonella effectors. Here we report that the TTSS-2 effector PipB2 interacts with the kinesin light chain, a subunit of the kinesin-1 motor complex that drives anterograde transport along microtubules. Translocation of PipB2 is both necessary and sufficient for the recruitment of kinesin-1 to the membrane of the Salmonella-containing vacuole. In vivo, PipB2 contributes to the attenuation of Salmonella mutant strains in mice. Taken together, our data indicate that the TTSS-2-mediated fine-tuning of kinesin-1 activity associated with the bacterial vacuole is crucial for the virulence of Salmonella.
Henry
Thomas
T
Centre d'Immunologie de Marseille-Luminy, Centre National de la Recherche Scientifique, Institut National de la Santé et de la Recherche Médicale, Université de la Méditerranée, Parc Scientifique de Luminy, Marseille, France.
Couillault
Carole
C
Rockenfeller
Patrick
P
Boucrot
Emmanuel
E
Dumont
Audrey
A
Schroeder
Nina
N
Hermant
Aurélie
A
Knodler
Leigh A
LA
Lecine
Patrick
P
Steele-Mortimer
Olivia
O
Borg
Jean-Paul
JP
Gorvel
Jean-Pierre
JP
Méresse
Stéphane
S
D000818:Animals; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D001854:Bone Marrow Cells / Q000166:cytology; D002454:Cell Differentiation; D002460:Cell Line; D002478:Cells, Cultured; D005260:Female; D005269:Femur / Q000166:cytology; D017353:Gene Deletion; D006367:HeLa Cells; D006801:Humans; D016547:Kinesins / Q000378:metabolism*; D008264:Macrophages / Q000378:metabolism / Q000382:microbiology; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D012475:Salmonella / Q000145:classification / Q000235:genetics / Q000254:growth & development / Q000378:metabolism* / Q000472:pathogenicity*; D012481:Salmonella Infections, Animal / Q000382:microbiology; D014617:Vacuoles / Q000382:microbiology; D014774:Virulence
D001426:Bacterial Proteins; C478165:PipB2 protein, Salmonella enterica; D016547:Kinesins