title: Type IV pilus retraction in pathogenic Neisseria is regulated by the PilC proteins.
abstract: Pathogenic Neisseria express type IV pili (tfp), which have been shown to play a central role in the interactions of bacteria with their environment. The regulation of piliation thus constitutes a central element in bacterial life cycle. The PilC proteins are outer membrane-associated proteins that have a key role in tfp biogenesis since PilC-null mutants appear defective for fibre expression. Moreover, tfp are also subjected to retraction, which is under the control of the PilT nucleotide-binding protein. In this work, we bring evidence that fibre retraction involves the translocation of pilin subunits to the cytoplasmic membrane. Furthermore, by engineering meningococcal strains that harbour inducible pilC genes, and with the use of meningococcus-cell interaction as a model for the sequential observation of fibre expression and retraction, we show that the PilC proteins regulate PilT-mediated fibre retraction.
authors.affiliation: INSERM U570, Faculté de Médecine Necker-Enfants Malades, Paris, France.
authors.forename: Philippe C
authors.initials: PC
authors.lastname: Morand
authors.forename: Emmanuelle
authors.initials: E
authors.lastname: Bille
authors.forename: Sandrine
authors.initials: S
authors.lastname: Morelle
authors.forename: Emmanuel
authors.initials: E
authors.lastname: Eugène
authors.forename: Jean-Luc
authors.initials: JL
authors.lastname: Beretti
authors.forename: Matthew
authors.initials: M
authors.lastname: Wolfgang
authors.forename: Thomas F
authors.initials: TF
authors.lastname: Meyer
authors.forename: Michael
authors.initials: M
authors.lastname: Koomey
authors.forename: Xavier
authors.initials: X
authors.lastname: Nassif
mesh_terms: D000251:Adenosine Triphosphatases / Q000378:metabolism; D001426:Bacterial Proteins / Q000378:metabolism; D002448:Cell Adhesion / Q000235:genetics / Q000502:physiology; D002462:Cell Membrane / Q000378:metabolism; D002478:Cells, Cultured; D017931:DNA Primers; D036781:Fimbriae Proteins / Q000235:genetics / Q000378:metabolism*; D010861:Fimbriae, Bacterial / Q000378:metabolism* / Q000502:physiology; D005455:Fluorescent Antibody Technique; D006801:Humans; D015151:Immunoblotting; D046529:Microscopy, Electron, Transmission; D020409:Molecular Motor Proteins / Q000378:metabolism; D009343:Neisseria / Q000235:genetics / Q000378:metabolism*; D009345:Neisseria meningitidis / Q000235:genetics / Q000378:metabolism / Q000648:ultrastructure; D009841:Oligonucleotides; D021381:Protein Transport / Q000502:physiology; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014169:Transformation, Bacterial
chemical_list: D001426:Bacterial Proteins; D017931:DNA Primers; D020409:Molecular Motor Proteins; D009841:Oligonucleotides; C079208:pilC protein, Neisseria gonorrhoeae; D036781:Fimbriae Proteins; D000251:Adenosine Triphosphatases