The heterologous expression of aGlycine maxhomolog of NONEXPRESSOR OF PR1 (NPR1) and α-hydroxynitrile glucosidase suppresses parasitism by the root pathogenMeloidogyne incognitainGossypium hirsutum

Abstract

Experiments in Glycine max (soybean) identified the expression of the salicylic acid signaling and defense gene NONEXPRESSOR OF PR1 (NPR1) in root cells (i.e., syncytium) parasitized by the plant parasitic nematode Heterodera glycines undergoing the process of resistance. Gm-NPR1-2 overexpression in G. max effectively suppresses parasitism by H. glycines. The heterologous expression of Gm-NPR1-2 in Gossypium hirsutum impairs the ability of the parasitic nematode Meloidogyne incognita to form root galls, egg sacs, eggs and second-stage juvenile (J2) nematodes.In related experiments, a G. max β-glycosidase (Gm-βg-4) related to Lotus japonicus secreted defense gene α-hydroxynitrile glucosidase LjBGD7 suppresses M. incognita parasitism. The results identify a cumulative negative effect that the transgenes have on M. incognita parasitism and demonstrate that the G. max-H. glycines pathosystem is a useful tool to identify defense genes that function in other agriculturally relevant plant species to plant parasitic nematodes with different strategies of parasitism.ARTICLE HISTORY

Transient expression of SbDhr2 and MeHNL in Gossypium hirsutum for herbivore deterrence assay with Spodoptera litura

“…These findings along with the previous work (Pant et al 2016) indicate that α-hydroxynitrile glucoside exists in G. hirsutum. There are possibilities that cyanide detoxification route/pathway (Gleadow and Moller 2014;Machingura et al 2016;Ting and Zschoche 1970;Zagrobelny et al 2004;Miller and Conn 1980;Sun et al 2018;Nielsen et al 2016;Pičmanová et al 2015) is more active in cotton.…”

Proteomics analysis reveals novel host molecular mechanisms associated with thermotherapy of ‘Ca. Liberibacter asiaticus’-infected citrus plants

“…Cherif et al [70] showed that an increase in beta-glucosidase activity in cucumber roots was associated with silicon-induced resistance to Pythium spp. Another study demonstrated that a soybean beta-glycosidase related to the Lotus japonicus defense gene, a-hydroxynitrile glucosidase, suppresses the parasitic activities of the nematode Meloidogyne incognita [71]. Furthermore, Miche et al [72] identified a putative endo-1,3-beta-D-glucosidase as part of the jasmonate-induced defense-responsive proteins in the roots of rice plants upon exposure to the endophyte Azoarcus sp.…”

The heterologous expression of a soybean (Glycine max) xyloglucan endotransglycosylase/hydrolase (XTH) in cotton (Gossypium hirsutum) suppresses parasitism by the root knot nematode Meloidogyne incognita

“…The heterologous expression of genes identified in one plant (G. max) in another recipient plant (G. hirsutum) has been demonstrated to be an effective way to understand the genetics of defense in various plant-parasitic nematode pathosystems by generating resistance outcomes under conditions where they may not normally exist. For example, a number of G. max genes and various bacterial effectors have been tested in the G. hirsutum-M. incognita pathosystem showing that they function to impair parasitism [37][38][39][40]. Pant et al (2016) showed that the G. max homolog of the A. thaliana transcription factor NONEXPRESSOR OF PR1 (NPR1) functions effectively to suppress M. incognita parasitism in G. hirsutum [37,41].…”

“…For example, a number of G. max genes and various bacterial effectors have been tested in the G. hirsutum-M. incognita pathosystem showing that they function to impair parasitism [37][38][39][40]. Pant et al (2016) showed that the G. max homolog of the A. thaliana transcription factor NONEXPRESSOR OF PR1 (NPR1) functions effectively to suppress M. incognita parasitism in G. hirsutum [37,41]. Furthermore, the bacterial effector harpin, first identified from the fire blight pathogen Erwinia amylovora, was capable of activating the expression of the coiled-coil nucleotide binding leucine rich repeat (CC-NB-LRR) NON-RACE SPECIFIC DISEASE RESISTANCE 1 (NDR1) in G. max [39,[42][43][44].…”

“…The induction of NDR1 can function in G. max on different pathogens, including the charcoal rot ascomycete (Macrophomina phaseolina), indicating a broad effectiveness for different types of pathogens [50]. Heterologous expression approaches were also used to examine these G. max genes in G. hirsutum to determine early signaling events that are transduced either through pathogen effectors (harpin), membrane receptors (NDR1), or transcription factors (NPR1) [14,[38][39][40]. However, these experiments have not taken into consideration the subsequent products of these signaling events including genes like XTH that were induced by harpin, NDR1, BIK1, NPR1 and MAPKs [13,14,39,40].…”