title: Early transcriptomic events in microdissected Arabidopsis nematode-induced giant cells.
abstract: Root-knot nematodes differentiate highly specialized feeding cells in roots (giant cells, GCs), through poorly characterized mechanisms that include extensive transcriptional changes. While global transcriptome analyses have used galls, which are complex root structures that include GCs and surrounding tissues, no global gene expression changes specific to GCs have been described. We report on the differential transcriptome of GCs versus root vascular cells, induced in Arabidopsis by Meloidogyne javanica at a very early stage of their development, 3 days after infection (d.p.i.). Laser microdissection was used to capture GCs and root vascular cells for microarray analysis, which was validated through qPCR and by a promoter-GUS fusion study. Results show that by 3 d.p.i., GCs exhibit major gene repression. Although some genes showed similar regulation in both galls and GCs, the majority had different expression patterns, confirming the molecular distinctiveness of the GCs within the gall. Most of the differentially regulated genes in GCs have no previously assigned function. Comparisons with other transcriptome analyses revealed similarities between GCs and cell suspensions differentiating into xylem cells. This suggests a molecular link between GCs and developing vascular cells, which represent putative GC stem cells. Gene expression in GCs at 3 d.p.i. was also found to be similar to crown galls induced by Agrobacterium tumefaciens, a specialized root biotroph.
authors.affiliation: Facultad de Ciencias del Medio Ambiente, Universidad de Castilla-La Mancha, Avenida de Carlos III s/n, 45071 Toledo, Spain.
authors.forename: Marta
authors.initials: M
authors.lastname: Barcala
authors.forename: Alejandra
authors.initials: A
authors.lastname: García
authors.forename: Javier
authors.initials: J
authors.lastname: Cabrera
authors.forename: Stuart
authors.initials: S
authors.lastname: Casson
authors.forename: Keith
authors.initials: K
authors.lastname: Lindsey
authors.forename: Bruno
authors.initials: B
authors.lastname: Favery
authors.forename: Gloria
authors.initials: G
authors.lastname: García-Casado
authors.forename: Roberto
authors.initials: R
authors.lastname: Solano
authors.forename: Carmen
authors.initials: C
authors.lastname: Fenoll
authors.forename: Carolina
authors.initials: C
authors.lastname: Escobar
mesh_terms: D000818:Animals; D017360:Arabidopsis / Q000166:cytology / Q000235:genetics / Q000378:metabolism* / Q000469:parasitology; D016000:Cluster Analysis; D020869:Gene Expression Profiling; D018507:Gene Expression Regulation, Developmental; D018506:Gene Expression Regulation, Plant; D015726:Giant Cells / Q000378:metabolism*; D006790:Host-Parasite Interactions / Q000235:genetics; D020411:Oligonucleotide Array Sequence Analysis; D018517:Plant Roots / Q000166:cytology / Q000235:genetics / Q000378:metabolism*; D018749:RNA, Plant / Q000235:genetics; D014431:Tylenchoidea
chemical_list: D018749:RNA, Plant