title: Laser Microdissection of Grapevine Leaves Reveals Site-Specific Regulation of Transcriptional Response to Plasmopara viticola.
abstract: Grapevine is one of the most important fruit crops in the world, and it is highly susceptible to downy mildew caused by the biotrophic oomycete Plasmopara viticola. Gene expression profiling has been used extensively to investigate the regulation processes of grapevine-P. viticola interaction, but all studies to date have involved the use of whole leaves. However, only a small fraction of host cells is in contact with the pathogen, so highly localized transcriptional changes of infected cells may be masked by the large portion of non-infected cells when analyzing the whole leaf. In order to understand the transcriptional regulation of the plant reaction at the sites of pathogen infection, we optimized a laser microdissection protocol and analyzed the transcriptional changes in stomata cells and surrounding areas of grapevine leaves at early stages of P. viticola infection. The results indicate that the expression levels of seven P. viticola-responsive genes were greater in microdissected cells than in whole leaves, highlighting the site-specific transcriptional regulation of the host response. The gene modulation was restricted to the stomata cells and to the surrounding areas of infected tissues, indicating that the host response is mainly located at the infection sites and that short-distance signals are implicated. In addition, due to the high sensitivity of the laser microdissection technique, significant modulations of three genes that were completely masked in the whole tissue analysis were detected. The protocol validated in this study could greatly increase the sensitivity of further transcriptomic studies of the grapevine-P. viticola interaction.
authors.affiliation: Research and Innovation Center, Fondazione Edmund Mach (FEM), Via E. Mach, 1, 38010 S. Michele all'Adige, Italy Department of Ecological and Biological Sciences, University of Tuscia, Via San Camillo de Lellis, 01100 Viterbo, Italy.
authors.forename: Luisa
authors.initials: L
authors.lastname: Lenzi
authors.affiliation: Department of Ecological and Biological Sciences, University of Tuscia, Via San Camillo de Lellis, 01100 Viterbo, Italy.
authors.forename: Carla
authors.initials: C
authors.lastname: Caruso
authors.affiliation: Technology Transfer Center, Fondazione Edmund Mach (FEM), Via E. Mach, 1, 38010 S. Michele all'Adige, Italy.
authors.forename: Pier Luigi
authors.initials: PL
authors.lastname: Bianchedi
authors.affiliation: Research and Innovation Center, Fondazione Edmund Mach (FEM), Via E. Mach, 1, 38010 S. Michele all'Adige, Italy.
authors.forename: Ilaria
authors.initials: I
authors.lastname: Pertot
authors.affiliation: Research and Innovation Center, Fondazione Edmund Mach (FEM), Via E. Mach, 1, 38010 S. Michele all'Adige, Italy michele.perazzolli@fmach.it.
authors.forename: Michele
authors.initials: M
authors.lastname: Perazzolli
mesh_terms: D020869:Gene Expression Profiling; D018506:Gene Expression Regulation, Plant; D054884:Host-Pathogen Interactions; D061346:Laser Capture Microdissection; D009868:Oomycetes / Q000502:physiology*; D010935:Plant Diseases / Q000382:microbiology*; D018515:Plant Leaves / Q000235:genetics / Q000382:microbiology; D054046:Plant Stomata / Q000235:genetics / Q000382:microbiology; D027843:Vitis / Q000235:genetics* / Q000382:microbiology
keywords: Gene expression; Laser microdissection; Oomycetes; Plant–pathogen interactions; Plasmopara viticola; Stomata; Vitis vinifera