Publications by authors named "Tom R Maier"

Pathogens must precisely tailor their gene expression to cause infection. However, a signaling cascade from host signal to effector production has remained elusive for metazoan pathogens. Here, we show that plants contain molecular signals, termed effectostimulins, that activate the first identified regulator of plant-parasitic nematode effectors.

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The soybean cyst nematode (SCN; ) facilitates infection by secreting a repertoire of effector proteins into host cells to establish a permanent feeding site composed of a syncytium of root cells. Among the diverse proteins secreted by the nematode, we were specifically interested in identifying proteases to pursue our goal of engineering decoy substrates that elicit an immune response when cleaved by an SCN protease. We identified a cysteine protease that we named Cysteine Protease 1 (CPR1), which was predicted to be a secreted effector based on transcriptomic data obtained from SCN esophageal gland cells, the presence of a signal peptide, and the lack of transmembrane domains.

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Plant-parasitic nematodes are a major threat to crop production in all agricultural systems. The scarcity of classical resistance genes highlights a pressing need to find new ways to develop nematode-resistant germplasm. Here, we sequence and assemble a high-quality phased genome of the model cyst nematode Heterodera schachtii to provide a platform for the first system-wide dual analysis of host and parasite gene expression over time, covering all major parasitism stages.

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The soybean cyst nematode (Heterodera glycines) is a sedentary plant parasite that exceeds billion USD annually in yield losses. This problem is exacerbated by H. glycines populations overcoming the limited sources of natural resistance in soybean and by the lack of effective and safe alternative treatments.

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The soybean cyst nematode is the most economically devastating pathogen of soybean in the United States and threatens to become even more damaging through the selection of virulent nematode populations in the field that can overcome natural resistance mechanisms in soybean cultivars. This pathogen, therefore, demands intense transcriptomic/genomic research inquiries into the biology of its parasitic mechanisms. delivers effector proteins that are produced in specialized gland cells into the soybean root to enable infection.

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Rapid plant genome evolution is crucial to adapt to environmental changes. Chromosomal rearrangements and gene copy number variation (CNV) are two important tools for genome evolution and sources for the creation of new genes. However, their emergence takes many generations.

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Soybean is an important worldwide crop, and farmers continue to experience significant yield loss due to the soybean cyst nematode (SCN), Heterodera glycines. This soil-borne roundworm parasite is rated the most important pathogen problem in soybean production. The infective nematodes enter into complex interactions with their host plant by inducing the development of specialized plant feeding cells that provide the parasites with nourishment.

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Background: Heterodera glycines, commonly referred to as the soybean cyst nematode (SCN), is an obligatory and sedentary plant parasite that causes over a billion-dollar yield loss to soybean production annually. Although there are genetic determinants that render soybean plants resistant to certain nematode genotypes, resistant soybean cultivars are increasingly ineffective because their multi-year usage has selected for virulent H. glycines populations.

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Plant-parasitic cyst nematodes synthesize and secrete effector proteins that are essential for parasitism. One such protein is the 10A07 effector from the sugar beet cyst nematode, Heterodera schachtii, which is exclusively expressed in the nematode dorsal gland cell during all nematode parasitic stages. Overexpression of H.

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Sedentary plant-parasitic nematodes engage in complex interactions with their host plants by secreting effector proteins. Some effectors of both root-knot nematodes (Meloidogyne spp.) and cyst nematodes (Heterodera and Globodera spp.

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Meloidogyne incognita is one of the most economically damaging plant pathogens in agriculture and horticulture. Identifying and characterizing the effector proteins which M. incognita secretes into its host plants during infection is an important step toward finding new ways to manage this pest.

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Esophageal glands of plant-parasitic nematodes are highly specialized cells whose gene expression products include secreted effector proteins, which govern nematode parasitism of host plants. Therefore, elucidating the transcriptomes of esophageal glands with the goal of identifying nematode effectors is a promising avenue to understanding nematode parasitism and its evolutionary origins as well as to devising nematode control strategies. We have developed a method to separate and isolate individual esophageal gland cells from multiple species of plant-parasitic nematodes while preserving RNA quality.

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The syncytium is a unique plant root organ whose differentiation is induced by plant-parasitic cyst nematodes to create a source of nourishment. Syncytium formation involves the redifferentiation and fusion of hundreds of root cells. The underlying regulatory networks that control this unique change of plant cell fate are not understood.

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Cyst nematodes are sedentary plant parasites that cause dramatic cellular changes in the plant root to form feeding cells, so-called syncytia. 10A06 is a cyst nematode secretory protein that is most likely secreted as an effector into the developing syncytia during early plant parasitism. A homolog of the uncharacterized soybean cyst nematode (Heterodera glycines), 10A06 gene was cloned from the sugar beet cyst nematode (Heterodera schachtii), which is able to infect Arabidopsis (Arabidopsis thaliana).

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Cyst nematodes are highly evolved sedentary plant endoparasites that use parasitism proteins injected through the stylet into host tissues to successfully parasitize plants. These secretory proteins likely are essential for parasitism as they are involved in a variety of parasitic events leading to the establishment of specialized feeding cells required by the nematode to obtain nourishment. With the advent of RNA interference (RNAi) technology and the demonstration of host-induced gene silencing in parasites, a new strategy to control pests and pathogens has become available, particularly in root-knot nematodes.

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Plant-parasitic cyst nematodes secrete a complex of cell wall-digesting enzymes, which aid in root penetration and migration. The soybean cyst nematode Heterodera glycines also produces a cellulose binding protein (Hg CBP) secretory protein. To determine the function of CBP, an orthologous cDNA clone (Hs CBP) was isolated from the sugar beet cyst nematode Heterodera schachtii, which is able to infect Arabidopsis thaliana.

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Plant-parasitic cyst nematodes induce the formation of specialized feeding cells in infected roots, which involves plant developmental processes that have been shown to be influenced by microRNAs (miRNAs) and other small RNAs. This observation provided the foundation to investigate the potential involvement of small RNAs in plant-cyst nematode interactions. First, we examined the susceptibilities of Arabidopsis DICER-like (dcl) and RNA-dependent RNA polymerase (rdr) mutants to the sugar beet cyst nematode Heterodera schachtii.

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Plant-parasitic nematodes are major agricultural pests worldwide and novel approaches to control them are sorely needed. We report the draft genome sequence of the root-knot nematode Meloidogyne incognita, a biotrophic parasite of many crops, including tomato, cotton and coffee. Most of the assembled sequence of this asexually reproducing nematode, totaling 86 Mb, exists in pairs of homologous but divergent segments.

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Ethylene-responsive element-binding proteins (EREBPs) are plant-specific transcription factors, many of which have been linked to plant defense responses. Conserved EREBP domains bind to the GCC box, a promoter element found in pathogenesis-related (PR) genes. We previously identified an EREBP gene from soybean (GmEREBP1) whose transcript abundance decreased in soybean cyst-nematode-infected roots of a susceptible cultivar, whereas it increased in abundance in infected roots of a resistant cultivar.

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