Chorismate mutase: an alternatively spliced parasitism gene and a diagnostic marker for three important Globodera nematode species

Abstract

The chorismate mutase gene is widely distributed in both cyst and root-knot nematode species and believed to play a critical role in nematode parasitism. In this study, we cloned a new chorismate mutase gene (Gt-cm-1) from Globodera tabacum and further characterized the gene structure in both G. tabacum and G. pallida, a closely related species of G. rostochiensis. The genomic clones of chorismate mutase genes from these two species were found to contain three introns with the second intron having unusual 5' and 3' splice sites. A previous study revealed that the chorismate mutase gene from G. rostochiensis is subject to alternative splicing through retention of intron 2, a process that allows for the generation of multiple mRNA transcripts from a single gene. As expected, we discovered that alternative splicing of the chorismate mutase gene is a conserved event in three Globodera species, supporting an important role of alternative splicing in regulating chorismate mutase gene function in plant parasitism by these nematodes. In addition to the potential suboptimal 5' and 3' splice sites and the small size of intron 2, detailed sequence analysis also identified candidate cis-acting elements that might be responsible for regulating intron retention of Globodera chorismate mutase genes. Based on genomic sequence variations observed, we developed TaqMan qPCR assays that provided a highly specific and sensitive identification of each Globodera species, revealing a new application of using the chorismate mutase gene as a valuable diagnostic marker for plant-parasitic nematodes.

A Plasmodium‐like virulence effector of the soybean cyst nematode suppresses plant innate immunity

“…In an outbred H. glycines field population, we identified four different HgGLAND18 isoforms, of which three appeared to have produced protein variants that differ in the number of exon 2 repeats ranging from 0 to 5. Thus, allelic variation and/or alternative splicing of repeat exons appear to generate extensive HgGLAND18 variation; the latter process has been documented for the chorismate mutase effector of plant-parasitic nematodes (Yu et al, 2011). Inter-and intrapopulation variation in the number of repeats has been documented for other cyst nematode effectors (Eves-van den Akker et al, 2014), and this feature may be of critical importance for infection.…”

Primer reporte de Melittia calabaza (Duckworth y Eichlin) (Lepidoptera: Sesiidae) en el Estado de Veracruz, México

“…Identificación molecular. La extracción de ADN se realizó a dos larvas frescas, utilizando el método descrito por Yu et al (2011), con algunas modificaciones. Las larvas se lavaron con agua destilada estéril, posteriormente se cortó un segmento de la parte abdominal del cual se utilizó un miligramo de tejido por cada espécimen.…”

Cellular Signaling Pathways and Posttranslational Modifications Mediated by Nematode Effector Proteins

“…The complete absence of CM substrate in animals provided the first clue that parasitic nematodes use molecular mimicry of host proteins to modulate secondary metabolic pathways (Doyle and Lambert, 2003). While the exact function of the secreted CMs remains unknown, the wide distribution of this class of effector proteins in plant-parasitic nematodes (Jones et al, 2003(Jones et al, , 2009Huang et al, 2005;Lu et al, 2008;Vanholme et al, 2009;Haegeman et al, 2011;Yu et al, 2011) suggests that they have a fundamental and conserved function in parasitism across nematode species.…”