title: Signaling pathways coordinating the alkaline pH response confer resistance to the hevein-type plant antimicrobial peptide Pn-AMP1 in Saccharomyces cerevisiae.
abstract: Genome-wide screening of Saccharomyces cerevisiae revealed that signaling pathways related to the alkaline pH stress contribute to resistance to plant antimicrobial peptide, Pn-AMP1. Plant antimicrobial peptides (AMPs) are considered to be promising candidates for controlling phytopathogens. Pn-AMP1 is a hevein-type plant AMP that shows potent and broad-spectrum antifungal activity. Genome-wide chemogenomic screening was performed using heterozygous and homozygous diploid deletion pools of Saccharomyces cerevisiae as a chemogenetic model system to identify genes whose deletion conferred enhanced sensitivity to Pn-AMP1. This assay identified 44 deletion strains with fitness defects in the presence of Pn-AMP1. Strong fitness defects were observed in strains with deletions of genes encoding components of several pathways and complex known to participate in the adaptive response to alkaline pH stress, including the cell wall integrity (CWI), calcineurin/Crz1, Rim101, SNF1 pathways and endosomal sorting complex required for transport (ESCRT complex). Gene ontology (GO) enrichment analysis of these genes revealed that the most highly overrepresented GO term was "cellular response to alkaline pH". We found that 32 of the 44 deletion strains tested (72 %) showed significant growth defects compared with their wild type at alkaline pH. Furthermore, 9 deletion strains (20 %) exhibited enhanced sensitivity to Pn-AMP1 at ambient pH compared to acidic pH. Although several hundred plant AMPs have been reported, their modes of action remain largely uncharacterized. This study demonstrates that the signaling pathways that coordinate the adaptive response to alkaline pH also confer resistance to a hevein-type plant AMP in S. cerevisiae. Our findings have broad implications for the design of novel and potent antifungal agents.
authors: Division of Applied Life Science and IALS, Gyeongsang National University, Jinju, 660-701, Republic of Korea.
authors: Youngho
authors: Y
authors: Kwon
authors: University of British Columbia, Pharmaceutical Sciences, Vancouver, BC, Canada.
authors: Jennifer
authors: J
authors: Chiang
authors: University of British Columbia, Pharmaceutical Sciences, Vancouver, BC, Canada.
authors: Grant
authors: G
authors: Tran
authors: University of British Columbia, Pharmaceutical Sciences, Vancouver, BC, Canada.
authors: Guri
authors: G
authors: Giaever
authors: University of British Columbia, Pharmaceutical Sciences, Vancouver, BC, Canada.
authors: Corey
authors: C
authors: Nislow
authors: National Academy of Agricultural Sciences, Rural Development Administration, Jeonju, 560-500, Republic of Korea.
authors: Bum-Soo
authors: BS
authors: Hahn
authors: Division of Applied Life Science and IALS, Gyeongsang National University, Jinju, 660-701, Republic of Korea. kwak@gnu.ac.kr.
authors: Youn-Sig
authors: YS
authors: Kwak
authors: Division of Science Education and Institute of Science Education, Chonbuk National University, Jeonju, 761-756, Republic of Korea. jkoo@jbnu.ac.kr.
authors: Ja-Choon
authors: JC
authors: Koo
mesh_terms: D023181:Antimicrobial Cationic Peptides / Q000378:metabolism* / Q000502:physiology; D055106:Genome-Wide Association Study; D006863:Hydrogen-Ion Concentration; D057865:Plant Immunity / Q000502:physiology; D037121:Plant Lectins / Q000378:metabolism / Q000502:physiology; D010940:Plant Proteins / Q000378:metabolism / Q000502:physiology*; D012441:Saccharomyces cerevisiae / Q000187:drug effects / Q000378:metabolism* / Q000502:physiology; D015398:Signal Transduction / Q000502:physiology*
chemical_list: D023181:Antimicrobial Cationic Peptides; D037121:Plant Lectins; D010940:Plant Proteins; C045875:hevein
keywords: Alkaline pH signaling; Antimicrobials; Cell wall integrity; Chemogenetic screen; Disease control; Hevein-type peptide; Pn-AMP1