title: Microbe-independent entry of oomycete RxLR effectors and fungal RxLR-like effectors into plant and animal cells is specific and reproducible.
abstract: A wide diversity of pathogens and mutualists of plant and animal hosts, including oomycetes and fungi, produce effector proteins that enter the cytoplasm of host cells. A major question has been whether or not entry by these effectors can occur independently of the microbe or requires machinery provided by the microbe. Numerous publications have documented that oomycete RxLR effectors and fungal RxLR-like effectors can enter plant and animal cells independent of the microbe. A recent reexamination of whether the RxLR domain of oomycete RxLR effectors is sufficient for microbe-independent entry into host cells concluded that the RxLR domains of Phytophthora infestans Avr3a and of P. sojae Avr1b alone are NOT sufficient to enable microbe-independent entry of proteins into host and nonhost plant and animal cells. Here, we present new, more detailed data that unambiguously demonstrate that the RxLR domain of Avr1b does show efficient and specific entry into soybean root cells and also into wheat leaf cells, at levels well above background nonspecific entry. We also summarize host cell entry experiments with a wide diversity of oomycete and fungal effectors with RxLR or RxLR-like motifs that have been independently carried out by the seven different labs that coauthored this letter. Finally we discuss possible technical reasons why specific cell entry may have been not detected by Wawra et al. (2013).
authors.affiliation: Department of Botany and Plant Pathology, Oregon State University, Corvallis, OR, USA. brett.tyler@oregonstate.edu
authors.forename: Brett M
authors.initials: BM
authors.lastname: Tyler
authors.forename: Shiv D
authors.initials: SD
authors.lastname: Kale
authors.forename: Qunqing
authors.initials: Q
authors.lastname: Wang
authors.forename: Kai
authors.initials: K
authors.lastname: Tao
authors.forename: Helen R
authors.initials: HR
authors.lastname: Clark
authors.forename: Kelly
authors.initials: K
authors.lastname: Drews
authors.forename: Vincenzo
authors.initials: V
authors.lastname: Antignani
authors.forename: Amanda
authors.initials: A
authors.lastname: Rumore
authors.forename: Tristan
authors.initials: T
authors.lastname: Hayes
authors.forename: Jonathan M
authors.initials: JM
authors.lastname: Plett
authors.forename: Isabelle
authors.initials: I
authors.lastname: Fudal
authors.forename: Biao
authors.initials: B
authors.lastname: Gu
authors.forename: Qinghe
authors.initials: Q
authors.lastname: Chen
authors.forename: Katharyn J
authors.initials: KJ
authors.lastname: Affeldt
authors.forename: Erwin
authors.initials: E
authors.lastname: Berthier
authors.forename: Gregory J
authors.initials: GJ
authors.lastname: Fischer
authors.forename: Daolong
authors.initials: D
authors.lastname: Dou
authors.forename: Weixing
authors.initials: W
authors.lastname: Shan
authors.forename: Nancy P
authors.initials: NP
authors.lastname: Keller
authors.forename: Francis
authors.initials: F
authors.lastname: Martin
authors.forename: Thierry
authors.initials: T
authors.lastname: Rouxel
authors.forename: Christopher B
authors.initials: CB
authors.lastname: Lawrence
mesh_terms: D020418:Algal Proteins / Q000235:genetics / Q000378:metabolism; D020816:Amino Acid Motifs / Q000502:physiology; D000818:Animals; D005656:Fungal Proteins / Q000235:genetics / Q000378:metabolism; D054884:Host-Pathogen Interactions; D006801:Humans; D009868:Oomycetes / Q000502:physiology*; D055750:Phytophthora infestans / Q000502:physiology*; D017434:Protein Structure, Tertiary; D021381:Protein Transport; D015203:Reproducibility of Results; D013025:Glycine max / Q000382:microbiology / Q000502:physiology*; D014908:Triticum / Q000382:microbiology / Q000502:physiology*; D037521:Virulence Factors / Q000235:genetics / Q000378:metabolism
chemical_list: C562170:AVR3a protein, Phytophthora infestans; D020418:Algal Proteins; D005656:Fungal Proteins; D037521:Virulence Factors
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