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GmSNAP18 and GmSHMT08 are two major genes conferring soybean cyst nematode (SCN) resistance in soybean. Overexpression of either of these two soybean genes would enhance the susceptibility of Arabidopsis to beet cyst nematode (BCN), while overexpression of either of their corresponding orthologs in Arabidopsis, AtSNAP2 and AtSHMT4, would suppress it. However, the mechanism by which these two pairs of orthologous genes boost or inhibit BCN susceptibility of Arabidopsis still remains elusive. In this study, Arabidopsis with simultaneously overexpressed GmSNAP18 and GmSHMT0 suppressed the growth of underground as well as above-ground parts of plants. Furthermore, Arabidopsis that simultaneously overexpressed GmSNAP18 and GmSHMT08 substantially stimulated BCN susceptibility and remarkably suppressed expression of AtPR1 in the salicylic acid signaling pathway. However, simultaneous overexpression of GmSNAP18 and GmSHMT08 did not impact the expression of AtJAR1 and AtHEL1 in the jasmonic acid and ethylene signaling pathways. GmSNAP18, GmSHMT08, and a pathogenesis-related (PR) protein, GmPR08-Bet VI, in soybean, and AtSNAP2, AtSHMT4, and AtPR1 in Arabidopsis could interact pair-wisely for mediating SCN and BCN resistance in soybean and Arabidopsis, respectively. Both AtSNAP2 and AtPR1 were localized on the plasma membrane, and AtSHMT4 was localized both on the plasma membrane and in the nucleus of cells. Nevertheless, after interactions, AtSNAP2 and AtPR1 could partially translocate into the cell nucleus. GmSNAP18 interacted with AtSHMT4, and GmSHMT4 interacted with AtSNAP2. However, neither GmSNAP18 nor GmSHMT08 interacted with AtPR1. Thus, no pairwise interactions among α-SNAPs, SHMTs, and AtPR1 occurred in Arabidopsis overexpressing either GmSNAP18 or GmSHMT08, or both of them. Transgenic Arabidopsis overexpressing either GmSNAP18 or GmSHMT08 substantially suppressed AtPR1 expression, while transgenic Arabidopsis overexpressing either AtSNAP2 or AtSHMT4 remarkably enhanced it. Taken together, no pairwise interactions of GmSNAP18, GmSHMT08, and AtPR1 with suppressed expression of AtPR1 enhanced BCN susceptibility in Arabidopsis. This study may provide a clue that nematode-resistant or -susceptible functions of plant genes likely depend on both hosts and nematode species. [ABSTRACT FROM AUTHOR]

Introduction: Plant parasitic cyst nematodes secrete a number of effectors into hosts to initiate formation of syncytia and infection causing huge yield losses. Objectives: The identified cyst nematode effectors are still limited, and the cyst nematode effectors-involved interaction mechanisms between cyst nematodes and plants remain largely unknown. Methods: The t-SNARE domain-containing effector in beet cyst nematode (BCN) was identified by In situ hybridization and immunohistochemistry analyses. The mutant of effector gene was designed by protein structure modeling analysis. The functions of effector gene and its mutant were analyzed by genetic transformation in Arabidopsis and infection by BCN. The protein–protein interaction was analyzed by yeast two hybrid, BiFC and pulldown assays. Gene expression was assayed by quantitative real-time PCR. Results: A t-SNARE domain-containing BCN HsSNARE1 was identified as an effector, and its mutant HsSNARE1-M1 carrying three mutations (E141D, A143T and −148S) that altered regional structure from random coils to α-helixes was designed and constructed. Transgenic analyses indicated that expression of HsSNARE1 significantly enhanced while expression of HsSNARE1-M1 and highly homologous HgSNARE1 remarkably suppressed BCN susceptibility of Arabidopsis. HsSNARE1 interacted with AtSNAP2 and AtPR1 via its t-SNARE domain and N-terminal, respectively, while HsSNARE1-M1/HgSNARE1 could not interact with AtPR1 but bound AtSNAP2. AtSNAP2, AtSHMT4 and AtPR1 interacted pairwise, but neither HsSNARE1 nor HsSNARE1-M1/HgSNARE1 could interact with AtSHMT4. Expression of HsSNARE1 significantly suppressed while expression of HsSNARE1-M1/HgSNARE1 considerably induced both AtSHMT4 and AtPR1 in transgenic Arabidopsis infected with BCN. Overexpression of AtPR1 significantly suppressed BCN susceptibility of Arabidopsis. Conclusions: This work identified a t-SNARE-domain containing cyst nematode effector HsSNARE1 and deciphered a molecular mode of action of the t-SNARE-domain containing cyst nematode effectors that HsSNARE1 promotes cyst nematode disease by interaction with both AtSNAP2 and AtPR1 and significant suppression of both AtSHMT4 and AtPR1, which is mediated by three structure change-causing amino acid residues.

[Display omitted] • A t -SNARE domain-containing effector HsSNARE1 was identified from beet cyst nematode (BCN). • Protein structure modeling analysis found that three mutations (E141D, A143T and −148S) altered regional structure of HsSNARE1 from random coils to α-helixes. • Expression of HsSNARE1 significantly enhanced while expression of its highly homologous soybean cyst nematode (SCN) HgSNARE1 and its mutant HsSNARE1-M1 , both of which carry those above-mentioned three mutations, remarkably suppressed BCN susceptibility of Arabidopsis. • HsSNARE1 promotes cyst nematode disease by interaction with both AtSNAP2 and AtPR1 via its t -SNARE domain and N -terminal uncharacterized fragment, respectively, and significant suppression of both AtSHMT4 and AtPR1. • This work pinpoints a new molecular mode of action of the t -SNARE-domain containing cyst nematode effectors. Plant parasitic cyst nematodes secrete a number of effectors into hosts to initiate formation of syncytia and infection causing huge yield losses. The identified cyst nematode effectors are still limited, and the cyst nematode effectors-involved interaction mechanisms between cyst nematodes and plants remain largely unknown. The t -SNARE domain-containing effector in beet cyst nematode (BCN) was identified by In situ hybridization and immunohistochemistry analyses. The mutant of effector gene was designed by protein structure modeling analysis. The functions of effector gene and its mutant were analyzed by genetic transformation in Arabidopsis and infection by BCN. The protein–protein interaction was analyzed by yeast two hybrid, BiFC and pulldown assays. Gene expression was assayed by quantitative real-time PCR. A t -SNARE domain-containing BCN HsSNARE1 was identified as an effector, and its mutant HsSNARE1-M1 carrying three mutations (E141D, A143T and −148S) that altered regional structure from random coils to α-helixes was designed and constructed. Transgenic analyses indicated that expression of HsSNARE1 significantly enhanced while expression of HsSNARE1-M1 and highly homologous HgSNARE1 remarkably suppressed BCN susceptibility of Arabidopsis. HsSNARE1 interacted with AtSNAP2 and AtPR1 via its t -SNARE domain and N -terminal, respectively, while HsSNARE1-M1/HgSNARE1 could not interact with AtPR1 but bound AtSNAP2. AtSNAP2, AtSHMT4 and AtPR1 interacted pairwise, but neither HsSNARE1 nor HsSNARE1-M1/HgSNARE1 could interact with AtSHMT4. Expression of HsSNARE1 significantly suppressed while expression of HsSNARE1-M1/HgSNARE1 considerably induced both AtSHMT4 and AtPR1 in transgenic Arabidopsis infected with BCN. Overexpression of AtPR1 significantly suppressed BCN susceptibility of Arabidopsis. This work identified a t -SNARE-domain containing cyst nematode effector HsSNARE1 and deciphered a molecular mode of action of the t -SNARE-domain containing cyst nematode effectors that HsSNARE1 promotes cyst nematode disease by interaction with both AtSNAP2 and AtPR1 and significant suppression of both AtSHMT4 and AtPR1 , which is mediated by three structure change-causing amino acid residues. [ABSTRACT FROM AUTHOR]

GmSNAP18 and GmSHMT08 are two major genes conferring soybean cyst nematode (SCN) resistance in soybean. Overexpression of either of these two soybean genes would enhance the susceptibility of Arabidopsis to beet cyst nematode (BCN), while overexpression of either of their corresponding orthologs in Arabidopsis, AtSNAP2 and AtSHMT4, would suppress it. However, the mechanism by which these two pairs of orthologous genes boost or inhibit BCN susceptibility of Arabidopsis still remains elusive. In this study, Arabidopsis with simultaneously overexpressed GmSNAP18 and GmSHMT0 suppressed the growth of underground as well as above-ground parts of plants. Furthermore, Arabidopsis that simultaneously overexpressed GmSNAP18 and GmSHMT08 substantially stimulated BCN susceptibility and remarkably suppressed expression of AtPR1 in the salicylic acid signaling pathway. However, simultaneous overexpression of GmSNAP18 and GmSHMT08 did not impact the expression of AtJAR1 and AtHEL1 in the jasmonic acid and ethylene signaling pathways. GmSNAP18, GmSHMT08, and a pathogenesis-related (PR) protein, GmPR08-Bet VI, in soybean, and AtSNAP2, AtSHMT4, and AtPR1 in Arabidopsis could interact pair-wisely for mediating SCN and BCN resistance in soybean and Arabidopsis, respectively. Both AtSNAP2 and AtPR1 were localized on the plasma membrane, and AtSHMT4 was localized both on the plasma membrane and in the nucleus of cells. Nevertheless, after interactions, AtSNAP2 and AtPR1 could partially translocate into the cell nucleus. GmSNAP18 interacted with AtSHMT4, and GmSHMT4 interacted with AtSNAP2. However, neither GmSNAP18 nor GmSHMT08 interacted with AtPR1. Thus, no pairwise interactions among α-SNAPs, SHMTs, and AtPR1 occurred in Arabidopsis overexpressing either GmSNAP18 or GmSHMT08, or both of them. Transgenic Arabidopsis overexpressing either GmSNAP18 or GmSHMT08 substantially suppressed AtPR1 expression, while transgenic Arabidopsis overexpressing either AtSNAP2 or AtSHMT4 remarkably enhanced it. Taken together, no pairwise interactions of GmSNAP18, GmSHMT08, and AtPR1 with suppressed expression of AtPR1 enhanced BCN susceptibility in Arabidopsis. This study may provide a clue that nematode-resistant or -susceptible functions of plant genes likely depend on both hosts and nematode species.

The rhg1-α GmSNAPIS (an α-SNAP) and Rhg4 GmSHMT08 are two major cloned genes conferring soybean cyst nematode resistance in Pekingtype soybeans, but the application of α-SNAPs and SHMTs in cyst nematode management remains elusive. In this study, GmSNAPIS and GmSHMTOS. together with their orthologs in Arabidopsis, AlSNAP2 (an α-SNAP) and AtSHMT4, were individually transformed into Arabidopsis Col-0 to generate the transgenic lines, and the growth of transgenic plants, beet cyst nematode (BCN) infection phenotypes, and AtSNAP2, AtSHMT4, and AtPR1 expression patterns were analyzed using Arabidopsis-BCN compatible interaction system, in addition with protein--protein interaction assay. Pulldown and BiFC assays revealed that GmSNAPI8 and GmSHMT08 interacted with AtSHMT4 and AtSNAP2, respectively. Plant root growth was not impacted by overexpression of GmSNAPIS and AtSNAP2. However, overexpression of GmSHMT08 and AtSHMT4 both increased plant height, additionally, overexpression of GmSHMT08 decreased rosette leaf size. Overexpression of GmSNAP 18 and GmSHMTOS both suppressed AtPR1 expression and significantly enhanced BCN susceptibility, while overexpression of AlSNAP2 and AtSHMT4 both substantially boosted AtPR1 expression and remarkably enhanced BCN resistance, in transgenic Arabidopsis. Overexpression of GmSNAP18 reduced, while overexpression oiAtSNAP2 unaltered AtSHMT4 expression. Overexpression of GmSHMT08 and AtSHMT4 both suppressed AtSNAP2 expression in transgenic Arabidopsis. Thus, different expression patterns of AtPR1 and AtSHMT4 are likely associated with opposite BCN infection phenotypes of Arabidopsis between overexpressing GmSNAP18 and AtSNAP2, and between overexpressing GmSHMT08 and AtSHMT4: and boosted AtPR1 expression are required for enhanced BCN resistance in Arabidopsis. All these results establish a basis for extension of α-SNAPs and SHMTs in cyst nematode management. [ABSTRACT FROM AUTHOR]

The rhg1-a GmSNAP18 (an α-SNAP ) and Rhg4 GmSHMT08 are two major cloned genes conferring soybean cyst nematode resistance in Peking-type soybeans, but the application of α-SNAPs and SHMTs in cyst nematode management remains elusive. In this study, GmSNAP18 and GmSHMT08 , together with their orthologs in Arabidopsis, AtSNAP2 (an α-SNAP ) and AtSHMT4 , were individually transformed into Arabidopsis Col-0 to generate the transgenic lines, and the growth of transgenic plants, beet cyst nematode (BCN) infection phenotypes, and AtSNAP2 , AtSHMT4 , and AtPR1 expression patterns were analyzed using Arabidopsis-BCN compatible interaction system, in addition with protein-protein interaction assay. Pulldown and BiFC assays revealed that GmSNAP18 and GmSHMT08 interacted with AtSHMT4 and AtSNAP2, respectively. Plant root growth was not impacted by overexpression of GmSNAP18 and AtSNAP2 . However, overexpression of GmSHMT08 and AtSHMT4 both increased plant height, additionally, overexpression of GmSHMT08 decreased rosette leaf size. Overexpression of GmSNAP18 and GmSHMT08 both suppressed AtPR1 expression and significantly enhanced BCN susceptibility, while overexpression of AtSNAP2 and AtSHMT4 both substantially boosted AtPR1 expression and remarkably enhanced BCN resistance, in transgenic Arabidopsis. Overexpression of GmSNAP18 reduced, while overexpression of AtSNAP2 unaltered AtSHMT4 expression. Overexpression of GmSHMT08 and AtSHMT4 both suppressed AtSNAP2 expression in transgenic Arabidopsis. Thus, different expression patterns of AtPR1 and AtSHMT4 are likely associated with opposite BCN infection phenotypes of Arabidopsis between overexpressing GmSNAP18 and AtSNAP2 , and between overexpressing GmSHMT08 and AtSHMT4 ; and boosted AtPR1 expression are required for enhanced BCN resistance in Arabidopsis. All these results establish a basis for extension of α-SNAPs and SHMTs in cyst nematode management.