The pilus and porin of Neisseria gonorrhoeae cooperatively induce Ca(2+) transients in infected epithelial cells.
Purified pili and porin from Neisseria quickly mobilize calcium (Ca(2+)) stores in monocytes and epithelial cells, ultimately influencing host cell viability as well as bacterial intracellular survival. Here, we examined the Ca(2+) transients induced in human epithelial cells during infection by live, piliated N. gonorrhoeae. Porin induced an influx of Ca(2+) from the extracellular medium less than 60 s post infection. The porin-induced transient is followed by a pilus-induced release of Ca(2+) from intracellular stores. The timing of these events is similar to that observed using purified proteins. Interestingly, the porin-induced Ca(2+) flux is required for the pilus-induced transient, indicating that the pilus-induced Ca(2+) release is, itself, Ca(2+) dependent. Several lines of evidence indicate that porin is present on pili. Moreover, pilus retraction strongly influences the porin- and pilus-induced Ca(2+) fluxes. These and other results strongly suggest that the pilus and porin cooperate to modulate calcium signalling in epithelial cells, and propose a model to explain how N. gonorrhoeae triggers Ca(2+) transients in the initial stages of pilus-mediated attachment.
Ayala
Patricia
P
Department of Molecular Microbiology and Immunology, Oregon Health and Science University, Portland, OR 97239, USA. ayalap@ohsu.edu
Wilbur
J Scott
JS
Wetzler
Lee M
LM
Tainer
John A
JA
Snyder
Aurelie
A
So
Magdalene
M
D002118:Calcium / Q000378:metabolism*; D004847:Epithelial Cells / Q000378:metabolism / Q000382:microbiology; D010861:Fimbriae, Bacterial / Q000378:metabolism*; D006801:Humans; D009344:Neisseria gonorrhoeae / Q000378:metabolism*; D018272:Porins / Q000378:metabolism*; D015398:Signal Transduction
D018272:Porins; C057699:porin protein, Neisseria; D002118:Calcium