title: A newly identified bacterial cell-penetrating peptide that reduces the transcription of pro-inflammatory cytokines.
abstract: Cell-permeable proteins, also called cell-penetrating peptides (CPPs), have the ability to cross cellular membranes, either alone or in association with bioactive cargo. We identified the Yersinia protein YopM as a novel bacterial cell-permeable protein. Here, we describe the ability of isolated recombinant YopM to enter host cells without a requirement for additional factors. This autonomous translocation of YopM was confirmed in several cell types, indicating that it is an intrinsic property of YopM. Using truncated versions of YopM, we show that either of the two N-terminal alpha-helices of YopM mediates translocation into the cells. Furthermore, the two alpha-helices are also able to deliver heterologous cargo, such as GFP or YopE. In addition, we found that, after entering the cells, YopM is functional and efficiently downregulates the transcription of pro-inflammatory cytokines (such as tumor necrosis factor-alpha and interleukins 12, 15 and 18). This finding suggests the potential use of YopM as a tool for protein delivery. Furthermore, it can lead to important advances in understanding and evaluating the intracellular and molecular function of YopM without the need for infection with Yersinia.
authors.affiliation: Westfälische Wilhelms-Universität Münster, Institut für Infektiologie, Zentrum für Molekularbiologie der Entzündung (ZMBE), Von-Esmarch-Strasse 56, D-48149 Münster, Germany.
authors.forename: Christian
authors.initials: C
authors.lastname: Rüter
authors.forename: Christoph
authors.initials: C
authors.lastname: Buss
authors.forename: Julia
authors.initials: J
authors.lastname: Scharnert
authors.forename: Gerhard
authors.initials: G
authors.lastname: Heusipp
authors.forename: M Alexander
authors.initials: MA
authors.lastname: Schmidt
mesh_terms: D001425:Bacterial Outer Membrane Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D016207:Cytokines / Q000235:genetics / Q000276:immunology*; D004721:Endoplasmic Reticulum / Q000378:metabolism; D049452:Green Fluorescent Proteins / Q000378:metabolism; D018922:HL-60 Cells; D006367:HeLa Cells; D006801:Humans; D007249:Inflammation / Q000276:immunology*; D021962:Membrane Microdomains / Q000378:metabolism; D017433:Protein Structure, Secondary; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D014158:Transcription, Genetic; D014409:Tumor Necrosis Factor-alpha / Q000235:genetics / Q000378:metabolism; D015008:Yersinia enterocolitica / Q000235:genetics / Q000378:metabolism* / Q000472:pathogenicity; D015010:Yersinia pestis / Q000378:metabolism / Q000472:pathogenicity
chemical_list: D001425:Bacterial Outer Membrane Proteins; D016207:Cytokines; D011993:Recombinant Fusion Proteins; D014409:Tumor Necrosis Factor-alpha; C060772:yopM protein, Yersinia; D049452:Green Fluorescent Proteins