Genome-wide study of the tomato SlMLO gene family and its functional characterization in response to the powdery mildew fungus oidium neolycopersici

Zheng Zheng, Michela Appiano, Stefano Pavan, Valentina Bracuto, Luigi Ricciardi, Richard G.F. Visser, Anne Marie A. Wolters, Yuling Bai*

*Corresponding author for this work

Research output: Contribution to journalArticleAcademicpeer-review

19 Citations (Scopus)

Abstract

The MLO (Mildew Locus O) gene family encodes plant-specific proteins containing seven transmembrane domains and likely acting in signal transduction in a calcium and calmodulin dependent manner. Some members of the MLO family are susceptibility factors toward fungi causing the powdery mildew disease. In tomato, for example, the loss-of-function of the MLO gene SlMLO1 leads to a particular form of powdery mildew resistance, called ol-2, which arrests almost completely fungal penetration. This type of penetration resistance is characterized by the apposition of papillae at the sites of plant-pathogen interaction. Other MLO homologs in Arabidopsis regulate root response to mechanical stimuli (AtMLO4 and AtMLO11) and pollen tube reception by the female gametophyte (AtMLO7). However, the role of most MLO genes remains unknown. In this work, we provide a genome-wide study of the tomato SlMLO gene family. Besides SlMLO1, other 15 SlMLO homologs were identified and characterized with respect to their structure, genomic organization, phylogenetic relationship, and expression profile. In addition, by analysis of transgenic plants, we demonstrated that simultaneous silencing of SlMLO1 and two of its closely related homologs, SlMLO5 and SlMLO8, confer higher level of resistance than the one associated with the ol-2 mutation. The outcome of this study provides evidence for functional redundancy among tomato homolog genes involved in powdery mildew susceptibility. Moreover, we developed a series of transgenic lines silenced for individual SlMLO homologs, which lay the foundation for further investigations aimed at assigning new biological functions to the MLO gene family.

Original languageEnglish
Article numberA380
JournalFrontiers in Plant Science
Volume7
DOIs
Publication statusPublished - 2016

Fingerprint

Oidium neolycopersici
powdery mildew
tomatoes
loci
fungi
genome
genes
resistance to penetration
calmodulin
pollen tubes
plant pathogens
signal transduction
transgenic plants
Arabidopsis
genetically modified organisms
mutation
genomics
calcium
phylogeny

Keywords

  • MLO gene family
  • Powdery mildew disease
  • Susceptibility
  • Tomato

Cite this

@article{58f6a582233e4296893580e8418892a2,
title = "Genome-wide study of the tomato SlMLO gene family and its functional characterization in response to the powdery mildew fungus oidium neolycopersici",
abstract = "The MLO (Mildew Locus O) gene family encodes plant-specific proteins containing seven transmembrane domains and likely acting in signal transduction in a calcium and calmodulin dependent manner. Some members of the MLO family are susceptibility factors toward fungi causing the powdery mildew disease. In tomato, for example, the loss-of-function of the MLO gene SlMLO1 leads to a particular form of powdery mildew resistance, called ol-2, which arrests almost completely fungal penetration. This type of penetration resistance is characterized by the apposition of papillae at the sites of plant-pathogen interaction. Other MLO homologs in Arabidopsis regulate root response to mechanical stimuli (AtMLO4 and AtMLO11) and pollen tube reception by the female gametophyte (AtMLO7). However, the role of most MLO genes remains unknown. In this work, we provide a genome-wide study of the tomato SlMLO gene family. Besides SlMLO1, other 15 SlMLO homologs were identified and characterized with respect to their structure, genomic organization, phylogenetic relationship, and expression profile. In addition, by analysis of transgenic plants, we demonstrated that simultaneous silencing of SlMLO1 and two of its closely related homologs, SlMLO5 and SlMLO8, confer higher level of resistance than the one associated with the ol-2 mutation. The outcome of this study provides evidence for functional redundancy among tomato homolog genes involved in powdery mildew susceptibility. Moreover, we developed a series of transgenic lines silenced for individual SlMLO homologs, which lay the foundation for further investigations aimed at assigning new biological functions to the MLO gene family.",
keywords = "MLO gene family, Powdery mildew disease, Susceptibility, Tomato",
author = "Zheng Zheng and Michela Appiano and Stefano Pavan and Valentina Bracuto and Luigi Ricciardi and Visser, {Richard G.F.} and Wolters, {Anne Marie A.} and Yuling Bai",
year = "2016",
doi = "10.3389/fpls.2016.00380",
language = "English",
volume = "7",
journal = "Frontiers in Plant Science",
issn = "1664-462X",
publisher = "Frontiers Research Foundation",

}

Genome-wide study of the tomato SlMLO gene family and its functional characterization in response to the powdery mildew fungus oidium neolycopersici. / Zheng, Zheng; Appiano, Michela; Pavan, Stefano; Bracuto, Valentina; Ricciardi, Luigi; Visser, Richard G.F.; Wolters, Anne Marie A.; Bai, Yuling.

In: Frontiers in Plant Science, Vol. 7, A380, 2016.

Research output: Contribution to journalArticleAcademicpeer-review

TY - JOUR

T1 - Genome-wide study of the tomato SlMLO gene family and its functional characterization in response to the powdery mildew fungus oidium neolycopersici

AU - Zheng, Zheng

AU - Appiano, Michela

AU - Pavan, Stefano

AU - Bracuto, Valentina

AU - Ricciardi, Luigi

AU - Visser, Richard G.F.

AU - Wolters, Anne Marie A.

AU - Bai, Yuling

PY - 2016

Y1 - 2016

N2 - The MLO (Mildew Locus O) gene family encodes plant-specific proteins containing seven transmembrane domains and likely acting in signal transduction in a calcium and calmodulin dependent manner. Some members of the MLO family are susceptibility factors toward fungi causing the powdery mildew disease. In tomato, for example, the loss-of-function of the MLO gene SlMLO1 leads to a particular form of powdery mildew resistance, called ol-2, which arrests almost completely fungal penetration. This type of penetration resistance is characterized by the apposition of papillae at the sites of plant-pathogen interaction. Other MLO homologs in Arabidopsis regulate root response to mechanical stimuli (AtMLO4 and AtMLO11) and pollen tube reception by the female gametophyte (AtMLO7). However, the role of most MLO genes remains unknown. In this work, we provide a genome-wide study of the tomato SlMLO gene family. Besides SlMLO1, other 15 SlMLO homologs were identified and characterized with respect to their structure, genomic organization, phylogenetic relationship, and expression profile. In addition, by analysis of transgenic plants, we demonstrated that simultaneous silencing of SlMLO1 and two of its closely related homologs, SlMLO5 and SlMLO8, confer higher level of resistance than the one associated with the ol-2 mutation. The outcome of this study provides evidence for functional redundancy among tomato homolog genes involved in powdery mildew susceptibility. Moreover, we developed a series of transgenic lines silenced for individual SlMLO homologs, which lay the foundation for further investigations aimed at assigning new biological functions to the MLO gene family.

AB - The MLO (Mildew Locus O) gene family encodes plant-specific proteins containing seven transmembrane domains and likely acting in signal transduction in a calcium and calmodulin dependent manner. Some members of the MLO family are susceptibility factors toward fungi causing the powdery mildew disease. In tomato, for example, the loss-of-function of the MLO gene SlMLO1 leads to a particular form of powdery mildew resistance, called ol-2, which arrests almost completely fungal penetration. This type of penetration resistance is characterized by the apposition of papillae at the sites of plant-pathogen interaction. Other MLO homologs in Arabidopsis regulate root response to mechanical stimuli (AtMLO4 and AtMLO11) and pollen tube reception by the female gametophyte (AtMLO7). However, the role of most MLO genes remains unknown. In this work, we provide a genome-wide study of the tomato SlMLO gene family. Besides SlMLO1, other 15 SlMLO homologs were identified and characterized with respect to their structure, genomic organization, phylogenetic relationship, and expression profile. In addition, by analysis of transgenic plants, we demonstrated that simultaneous silencing of SlMLO1 and two of its closely related homologs, SlMLO5 and SlMLO8, confer higher level of resistance than the one associated with the ol-2 mutation. The outcome of this study provides evidence for functional redundancy among tomato homolog genes involved in powdery mildew susceptibility. Moreover, we developed a series of transgenic lines silenced for individual SlMLO homologs, which lay the foundation for further investigations aimed at assigning new biological functions to the MLO gene family.

KW - MLO gene family

KW - Powdery mildew disease

KW - Susceptibility

KW - Tomato

U2 - 10.3389/fpls.2016.00380

DO - 10.3389/fpls.2016.00380

M3 - Article

VL - 7

JO - Frontiers in Plant Science

JF - Frontiers in Plant Science

SN - 1664-462X

M1 - A380

ER -