Retraction

Abstract

The authors of the above article request that it be retracted from The Plant Cell and issue the following statement:After publication of the article, we discovered irregularities and inappropriate data manipulation in Figure 6C produced by the first author Ching-Wei Chen from the Zimmerli laboratory. Specifically, the same blot image improperly appears twice in Figure 6, once in Figure 6A corresponding to the IP: a-GFP blot for FLS2-GFP and again in Figure 6C as IP: a-GFP for CERK1-GFP. We repeated these experiments but found that the original results associated with Figure 6C could not be replicated and instead suggest the potential for interaction between IOS1 and CERK1 in vivo in Nicotiana benthamiana. This raises questions about some of the conclusions of the article, and we feel the best course of action is to retract the article. We believe a major conclusion of the article remains unaffected, namely, that IOS1 is involved in the regulation of flg22-and elf18-triggered responses. However, we cannot rule out an additional role for IOS1 in mediating signaling by CERK1. We are undertaking follow-up experiments to verify the major findings and clarify the role of IOS1 in plant immunity signaling.www.plantcell.org/cgi/doi/10.1105/tpc.15.00374The Plant Cell, Vol. 27: 1563, May 2015 Plasma membrane-localized pattern recognition receptors (PRRs) such as FLAGELLIN SENSING2 (FLS2), EF-TU RECEPTOR (EFR), and CHITIN ELICITOR RECEPTOR KINASE1 (CERK1) recognize microbe-associated molecular patterns (MAMPs) to activate pattern-triggered immunity (PTI). A reverse genetics approach on genes responsive to the priming agent b-aminobutyric acid (BABA) revealed IMPAIRED OOMYCETE SUSCEPTIBILITY1 (IOS1) as a critical PTI player. Arabidopsis thaliana ios1 mutants were hypersusceptible to Pseudomonas syringae bacteria. Accordingly, ios1 mutants showed defective PTI responses, notably delayed upregulation of the PTI marker gene FLG22-INDUCED RECEPTOR-LIKE KINASE1, reduced callose deposition, and mitogen-activated protein kinase activation upon MAMP treatment. Moreover, Arabidopsis lines overexpressing IOS1 were more resistant to bacteria and showed a primed PTI response. In vitro pull-down, bimolecular fluorescence complementation, coimmunoprecipitation, and mass spectrometry analyses supported the existence of complexes between the membrane-localized IOS1 and BRASSINOSTEROID INSENSITIVE1-ASSOCIATED KINASE1 (BAK1)-dependent PRRs FLS2 and EFR, as well as with the BAK1-independent PRR CERK1. IOS1 also associated with BAK1 in a ligand-independent manner and positively regulated FLS2-BAK1 complex formation upon MAMP treatment. In addition, IOS1 was critical for chitinmediated PTI. Finally, ios1 mutants were defective in BABA-induced resistance and priming. This work reveals IOS1 as a novel regulatory protein of FLS2-, EFR-, and CERK1-mediated signaling pathways that primes PTI activation. INTRODUCTIONPlants possess multilayered recognition systems that detect pathogens at various stages of infection and proliferation. Recognition of m...