title: [VPA1045 and VPA1049 of Vibrio parahaemolyticus regulate translocation of Hcp2].
abstract: OBJECTIVE
  Vibrio parahaemolyticus causes acute gastroenteritis by secreting a number of virulence factors including two sets of type VI secretion systems (T6SS1 and T6SS2). However, it remains unknown how T6SS is regulated in the bacterium and what kinds of effects the systems have on adhesion onto and invasion into the host cells. This study was attempted to examine if VPA1045 and VPA1049 regulate T6SS2.
  
  
  METHODS
  Vpa1045 and Vpa1049 deletion mutants were constructed by homologous recombination. Real-time PCR was performed to examine the transcription level of the translocon protein gene hcp2 in V. parahaemolyticus clinical strain HZ and its mutants. Western blot was used to analyze the levels of expression and translocation of Hcp2.
  
  
  RESULTS
  Both VPA1045 and VPA1049 contain the Che-Y domain, and belong to the two-component regulators. Deletion of either Vpa1045 or Vpa1049 did not affect expression and transcription of Hcp2, but decreased translocation of Hcp2 in the supernatant of V. parahaemolycus. Bacterial adherence to the HeLa monolayers was also significantly reduced as compared with their parent strains.
  
  
  CONCLUSIONS
  The two-component regulators VPA1045 and VPA1049 regulate T6SS2 of V. parahaemolyticus post-translationally by up-regulating Hcp2 translocation.
authors.affiliation: Zhejiang University Institute of Preventive Veterinary Medicine, Zhejiang Provincial Key Laboratory of Preventive Veterinary Medicine, Hangzhou 310058, China. yuyingye@zju.edu.cn
authors.forename: Ying
authors.initials: Y
authors.lastname: Yu
authors.forename: Yan
authors.initials: Y
authors.lastname: Zhang
authors.forename: Jun
authors.initials: J
authors.lastname: Li
authors.forename: Hong
authors.initials: H
authors.lastname: Yang
authors.forename: Houhui
authors.initials: H
authors.lastname: Song
authors.forename: Weihuan
authors.initials: W
authors.lastname: Fang
mesh_terms: D001422:Bacterial Adhesion; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D058947:Bacterial Secretion Systems; D015964:Gene Expression Regulation, Bacterial; D006367:HeLa Cells; D006801:Humans; D021381:Protein Transport; D014735:Vibrio Infections / Q000382:microbiology*; D014736:Vibrio parahaemolyticus / Q000235:genetics / Q000378:metabolism*
chemical_list: D001426:Bacterial Proteins; D058947:Bacterial Secretion Systems