Exploration of the late stages of the tomato–Phytophthora parasitica interactions through histological analysis and generation of expressed sequence tags

Abstract

Summary• The oomycete Phytophthora parasitica is a soilborne pathogen infecting numerous plants. The infection process includes an initial biotrophic stage, followed by a necrotrophic stage. The aim here was to identify genes that are involved in the late stages of infection.• Using the host tomato and a transformed strain of P. parasitica expressing the green fluorescent protein (GFP), the various infection steps from recognition of the host to the colonization of plant tissues were studied. This late stage was selected to generate 4000 ESTs (expressed sequence tags), among which approx. 80% were from the pathogen.• Comparison with an EST data set created previously from in vitro growth of P. parasitica allowed the identification of several genes, the expression of which might be regulated during late stages of infection.• Changes in gene expression of several candidate genes predicted from in silico analysis were validated by quantitative RT-PCR experiments. These results give insights into the molecular bases of the necrotrophic stage of an oomycete pathogen.

Development of a multiplex PCR assay for rapid and simultaneous detection of rubber tree pathogens Phytophthora spp. and P. palmivora

“…Moreover, it has been demonstrated that biomass of Phytophthora spp. such as P. infestans and P. ramorum in infected tissues is generally low 29 . Other possible reason is that the disease expressing materials tested here might not be caused by Phytophthora spp.…”

Green fluorescent protein (GFP) as a vital marker for studying the interaction of Phytophthora sojae and soybean

“…nicotianae [15,16] and P. brassicae [17] . In this paper we extend the use of GFP to P. sojae using the CaCl 2 /PEG-mediated transformation method.…”

“…This method has been successfully used for the expression of marker genes such as gus and gfp in Phytophthora spp. [12][13][14][15][16][17][18] . Here, we describe the first successful transformation of the oomycete P. sojae with the reporter gene gfp.…”

“…This method has been successfully used for the expression of marker genes such as β-glucuronidase gene (gus) in P. infestans [12,13] and green fluorescent protein gene (gfp) in Phytophthora palmivora [14] , Phytophthora parasitica var. nicotianae [15,16] and Phytophthora brassicae [17] , which provide two excellent reporter systems for studying the development, gene expression and infection events of oomycetes. To determine the location and time of in planta-induced gene ipiO expression, cytological assays were performed using a P. infestans transformant expressing a transcriptional fusion between the ipiO promoter and gus gene [18] .…”

“…Another reporter gene, gfp gene was used in P. parasitica var. nicotianae [15,16] and P. palmivora [14] , both as a quantitative reporter of gene induction and as a vital marker allowing the study of development of oomycetes in vitro and in the host plants. Remarkably, induced resistance was studied in the model pathosystem Arabidopsis-P. brassicae in comparison with the late blight disease of potato using the gfp gene [17] .…”