The N. gonorrhoeae type IV pilus stimulates mechanosensitive pathways and cytoprotection through a pilT-dependent mechanism.
The Neisseria gonorrhoeae type IV pilus is a retractile appendage that can generate forces near 100 pN. We tested the hypothesis that type IV pilus retraction influences epithelial cell gene expression by exerting tension on the host membrane. Wild-type and retraction-defective bacteria altered the expression of an identical set of epithelial cell genes during attachment. Interestingly, pilus retraction, per se, did not regulate novel gene expression but, rather, enhanced the expression of a subset of the infection-regulated genes. This is accomplished through mitogen-activated protein kinase activation and at least one other undefined stress-activated pathway. These results can be reproduced by applying artificial force on the epithelial membrane, using a magnet and magnetic beads. Importantly, this retraction-mediated signaling increases the ability of the cell to withstand apoptotic signals triggered by infection. We conclude that pilus retraction stimulates mechanosensitive pathways that enhance the expression of stress-responsive genes and activate cytoprotective signaling. A model for the role of pilus retraction in influencing host cell survival is presented.
Howie
Heather L
HL
Department of Molecular Microbiology and Immunology, Oregon Health and Science University, Portland, Oregon, USA. howieh@ohsu.edu <howieh@ohsu.edu>
Glogauer
Michael
M
So
Magdalene
M
D000251:Adenosine Triphosphatases / Q000502:physiology*; D001426:Bacterial Proteins / Q000502:physiology*; D002460:Cell Line; D003228:Conjunctiva / Q000382:microbiology; D010861:Fimbriae, Bacterial / Q000235:genetics / Q000502:physiology*; D015964:Gene Expression Regulation, Bacterial; D006801:Humans; D007413:Intestinal Mucosa / Q000382:microbiology; D020935:MAP Kinase Signaling System / Q000235:genetics; D008465:Mechanoreceptors / Q000502:physiology*; D020409:Molecular Motor Proteins / Q000502:physiology*; D008969:Molecular Sequence Data; D009344:Neisseria gonorrhoeae / Q000235:genetics* / Q000472:pathogenicity; D020411:Oligonucleotide Array Sequence Analysis; D020133:Reverse Transcriptase Polymerase Chain Reaction
D001426:Bacterial Proteins; D020409:Molecular Motor Proteins; D000251:Adenosine Triphosphatases