title: Lon Protease Is Involved in RhpRS-Mediated Regulation of Type III Secretion in Pseudomonas syringae.
abstract: Pseudomonas syringae depends on the type III secretion system (T3SS) to directly translocate effectors into host cells. Previously, we reported a nonpathogenic rhpS mutant, suggesting that the two-component transduction system rhpRS is an important regulator of T3SS in P. syringae. rhpRS regulates itself and a variety of downstream genes under an inverted repeat element promoter in a phosphorylation-dependent manner. Here, we identify lon as a suppressor of the rhpS mutant through transposon screening. A lon/rhpS double mutant restored the phenotypes of the rhpS mutant. The expression level of lon was higher in rhpS and other T3SS-deficient mutants than the wild-type strain, suggesting a negative feedback mechanism between lon and T3SS genes. lon was also induced by a novel T3SS inhibitor, acetate, which substantially compromises the activation of T3SS genes in minimal medium and bacterial growth in host plants.
authors.affiliation: Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, TEDA Institute of Biological Sciences and Biotechnology, Nankai University, 23 Hongda Street, Tianjin 300457, China.
authors.forename: Tianhong
authors.initials: T
authors.lastname: Zhou
authors.affiliation: Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, TEDA Institute of Biological Sciences and Biotechnology, Nankai University, 23 Hongda Street, Tianjin 300457, China.
authors.forename: Chunyan
authors.initials: C
authors.lastname: Yin
authors.affiliation: Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, TEDA Institute of Biological Sciences and Biotechnology, Nankai University, 23 Hongda Street, Tianjin 300457, China.
authors.forename: Yingchao
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, TEDA Institute of Biological Sciences and Biotechnology, Nankai University, 23 Hongda Street, Tianjin 300457, China.
authors.forename: Heng
authors.initials: H
authors.lastname: Shi
authors.affiliation: Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, TEDA Institute of Biological Sciences and Biotechnology, Nankai University, 23 Hongda Street, Tianjin 300457, China.
authors.forename: Jingru
authors.initials: J
authors.lastname: Wang
authors.affiliation: Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, TEDA Institute of Biological Sciences and Biotechnology, Nankai University, 23 Hongda Street, Tianjin 300457, China.
authors.forename: Linbo
authors.initials: L
authors.lastname: Sun
authors.affiliation: Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, TEDA Institute of Biological Sciences and Biotechnology, Nankai University, 23 Hongda Street, Tianjin 300457, China.
authors.forename: Xiaolong
authors.initials: X
authors.lastname: Shao
authors.affiliation: Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, TEDA Institute of Biological Sciences and Biotechnology, Nankai University, 23 Hongda Street, Tianjin 300457, China.
authors.forename: Ruxia
authors.initials: R
authors.lastname: Gao
authors.affiliation: Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, TEDA Institute of Biological Sciences and Biotechnology, Nankai University, 23 Hongda Street, Tianjin 300457, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Wang
authors.affiliation: Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, TEDA Institute of Biological Sciences and Biotechnology, Nankai University, 23 Hongda Street, Tianjin 300457, China.
authors.forename: Xin
authors.initials: X
authors.lastname: Deng
mesh_terms: D000085:Acetates / Q000494:pharmacology; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D002874:Chromosome Mapping; D015964:Gene Expression Regulation, Bacterial; D018551:Solanum lycopersicum / Q000382:microbiology*; D008954:Models, Biological; D016254:Mutagenesis, Insertional; D010641:Phenotype; D010766:Phosphorylation; D010935:Plant Diseases / Q000382:microbiology*; D011401:Promoter Regions, Genetic / Q000235:genetics; D049070:Protease La / Q000235:genetics / Q000378:metabolism*; D044224:Pseudomonas syringae / Q000235:genetics*; D000069296:Type III Secretion Systems / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*
chemical_list: D000085:Acetates; D001426:Bacterial Proteins; D000069296:Type III Secretion Systems; D049070:Protease La