title: An insight into critical endocycle genes for plant-parasitic nematode feeding sites establishment.
abstract: Root-knot and cyst nematodes are biotrophic parasites that invade the root apex of host plants and migrate toward the vascular cylinder where they cause the differentiation of root cells into galls (or root-knots) containing hypertrophied multinucleated giant-feeding cells, or syncytia, respectively. The precise molecular mechanisms that drive the formation of such unique nematode feeding sites are still far-off from being completely understood. The diverse gene expression changes occurring within the host cells suggest that both types of plant-parasitic nematodes modulate a variety of plant processes. Induction and repression of genes belonging to the host cell cycle control machinery have shown to be essential to drive the formation of such specialized nematode feeding cells. We demonstrate that nematodes usurp key components regulating the endocycle in their favor. This is illustrated by the involvement of anaphase-promoting complex (APC) genes (CCS52A and CCS52B), the endocycle repressor DP-E2F-like (E2F/DEL1) gene and the ROOT HAIRLESS 1 PROTEIN (RHL1), which is part of a multiprotein complex of the toposiomerase VI, in the proper formation of nematode feeding sites. Altering the expression of these genes in Arabidopsis plants by down- or overexpressing strategies strongly influences the extent of endoreduplication in both types of nematode feeding site leading to a disturbance of the nematode's life cycle and reproduction.
authors.affiliation: Institut National de la Recherche Agronomique; Centre National de la Recherche Scientifique; Université de Nice-Sophia Antipolis; Sophia-Antipolis, France; † Current affiliation: Lab. Nematologia/ICAAM-Instituto de Ciências Agrárias e Ambientais Mediterrânicas; Universidade de Évora; Évora, Portugal.
authors.forename: Paulo
authors.initials: P
authors.lastname: Vieira
authors.forename: Tina
authors.initials: T
authors.lastname: Kyndt
authors.forename: Godelieve
authors.initials: G
authors.lastname: Gheysen
authors.forename: Janice
authors.initials: J
authors.lastname: de Almeida Engler
mesh_terms: D000818:Animals; D017360:Arabidopsis / Q000235:genetics / Q000469:parasitology*; D029681:Arabidopsis Proteins / Q000235:genetics*; D018797:Cell Cycle Proteins / Q000235:genetics*; D004268:DNA-Binding Proteins; D062951:Endoreduplication; D005247:Feeding Behavior; D017343:Genes, Plant; D015726:Giant Cells / Q000502:physiology; D006790:Host-Parasite Interactions / Q000235:genetics; D008938:Mitosis; D009348:Nematoda / Q000502:physiology*; D009687:Nuclear Proteins / Q000235:genetics*; D014157:Transcription Factors / Q000235:genetics*
chemical_list: D029681:Arabidopsis Proteins; C583229:CCS52B protein, Arabidopsis; D018797:Cell Cycle Proteins; C500416:DEL1 protein, Arabidopsis; D004268:DNA-Binding Proteins; D009687:Nuclear Proteins; C113289:RHL1 protein, Arabidopsis; D014157:Transcription Factors
keywords: Arabidopsis; cell cycle; cyst nematode; endocycle; root-knot nematode