Diverse RNA viruses elicit the expression of common sets of genes in susceptible Arabidopsis thaliana plants

Abstract

SummarySystemic infections of plants by viruses require that viruses modify host cells in order to facilitate infections. These modifications include induction of host factors required for replication, propagation and movement, and suppression of host defense responses, which are likely to be associated with changes in host gene expression. Past studies of the effects of viral infection on gene expression in susceptible hosts have been limited to only a handful of genes. To gain broader insight into the responses elicited by viruses in susceptible hosts, high-density oligonucleotide probe microarray technology was used. Arabidopsis leaves were either mock inoculated or inoculated with cucumber mosaic cucumovirus, oil seed rape tobamovirus, turnip vein clearing tobamovirus, potato virus X potexvirus, or turnip mosaic potyvirus. Inoculated leaves were collected at 1, 2, 4, and 5 days after inoculation, total RNA was isolated, and samples were hybridized to Arabidopsis GeneChip microarrays (Affymetrix). Microarray hybridization revealed co-ordinated changes in gene expression in response to infection by diverse viruses. These changes include virus-general and virusspecific alterations in the expression of genes associated with distinct defense or stress responses. Analyses of the promoters of these genes further suggest that diverse RNA viruses elicit common responses in susceptible plant hosts through signaling pathways that have not been previously characterized.

Virus Induction of Heat Shock Protein 70 Reflects a General Response to Protein Accumulation in the Plant Cytosol

“…We and others have reported the induction of HSP70 by a wide range of viruses in diverse host plants, including pea (Pisum sativum), N. benthamiana, squash (Cucurbita pepo), tobacco (Nicotiana tabacum), and Arabidopsis (Aranda et al, 1996;Escaler et al, 2000;Havelda and Maule, 2000;Jockusch et al, 2001;Whitham et al, 2003). Based on the differential induction of heat-inducible genes Figure 3.…”

“…In addition to its part in responses to abiotic stress, HSP70 also functions in response to pathogen attack. Hence, in plants, HSP70 and HSP90 are essential components of the hypersensitive response defense mechanism (Kanzaki et al, 2003), and HSP70 is induced by virus infection in both animal and plant cells (Aranda and Maule, 1998;Whitham et al, 2003).…”

ARGONAUTE2 Mediates RNA-Silencing Antiviral Defenses againstPotato virus Xin Arabidopsis

“…PVX is the type member of the genus Potexvirus (Martelli et al, 2007) and infects several solanaceous hosts, but Arabidopsis is considered a nonhost for PVX. However, an Arabidopsis-infecting strain of PVX (PVX 2.7) has been described and used in microarray expression studies (Whitham et al, 2003). We show here that PVX 2.7 can infect Arabidopsis because of the presence of a second virus, Pepper ringspot virus (PepRSV).…”

Differential Tomato Transcriptomic Responses Induced by Pepino Mosaic Virus Isolates with Differential Aggressiveness

“…Since viruses are obligate intracellular parasites that hijack host cellular functions and resources for their replication and movement, they generally induce a wide variety of alterations in host gene expression and cell physiology (Whitham et al, 2003(Whitham et al, , 2006. In recent years, the use of transcriptomics approaches, such as microarrays and subtractive libraries, has resulted in significant advances in identifying such responses to viruses (Whitham et al, 2003(Whitham et al, , 2006Marathe et al, 2004;Dardick, 2007;Yang et al, 2007). Many microarray analyses are initiated to discover novel genes with effective host defense responses to obtain candidate genes for functional analysis (Wise et al, 2007).…”