title: Expression of Arabidopsis pathogenesis-related genes during nematode infection.
abstract: The expression pattern of pathogenesis-related genes PR-1 to PR-5 was examined in the roots and leaves of Arabidopsis thaliana plants on infection with beet-cyst (Heterodera schachtii) and root-knot (Meloidogyne incognita) nematodes. During H. schachtii parasitism of Arabidopsis, the expression of PR-1, PR-2 and PR-5, which are considered to be markers for salicylic acid (SA)-dependent systemic acquired resistance (SAR), was induced in both roots and leaves of infected plants. In addition, the expression of PR-3 and PR-4, which are used as markers for jasmonic acid (JA)-dependent SAR, was not altered in roots, but in the leaves of H. schachtii-infected plants, the expression PR-3 was induced, whereas the expression of PR-4 was down-regulated. During M. incognita infection of Arabidopsis, the expression of PR-1, PR-2 and PR-5 was highly induced in roots, as was PR-3 to a lesser extent, but the expression of PR-4 was not altered, indicating that infection with M. incognita activated both SA- and JA-dependent SAR in roots. However, all PRgenes examined (PR-1 to PR-5) were down-regulated in the leaves of M. incognita-infected plants, suggesting the suppression of both SA- and JA-dependent SAR. Furthermore, constitutive expression of a single PR in Arabidopsis altered the transcription patterns of other PR genes, and the over-expression of PR-1 reduced successful infection by both H. schachtii and M. incognita, whereas the over-expression of PR-3 reduced host susceptibility to M. incognita but had no effect on H. schachtii parasitism. The results suggest that fundamental differences in the mechanisms of infection by beet-cyst and root-knot nematodes differentially regulate PR protein production and mobilization within susceptible host plants.
authors: North Carolina State University, Department of Plant Pathology, Raleigh, NC 27607, USA.
authors: Noureddine
authors: N
authors: Hamamouch
authors: Chunying
authors: C
authors: Li
authors: Pil Joon
authors: PJ
authors: Seo
authors: Chung-Mo
authors: CM
authors: Park
authors: Eric L
authors: EL
authors: Davis
mesh_terms: D000818:Animals; D017360:Arabidopsis / Q000235:genetics* / Q000469:parasitology*; D029681:Arabidopsis Proteins / Q000235:genetics; D003517:Cyclopentanes / Q000378:metabolism; D018506:Gene Expression Regulation, Plant / Q000235:genetics; D009348:Nematoda / Q000472:pathogenicity*; D054883:Oxylipins / Q000378:metabolism; D010935:Plant Diseases / Q000235:genetics / Q000469:parasitology; D020133:Reverse Transcriptase Polymerase Chain Reaction; D020156:Salicylic Acid / Q000378:metabolism; D015398:Signal Transduction / Q000235:genetics / Q000502:physiology
chemical_list: D029681:Arabidopsis Proteins; D003517:Cyclopentanes; D054883:Oxylipins; C011006:jasmonic acid; D020156:Salicylic Acid