Co-regulation of the Glycine max soluble N-ethylmaleimide-sensitive fusion protein attachment protein receptor (SNARE)-containing regulon occurs during defense to a root pathogen.

Genes functioning in membrane fusion were originally identified genetically in Saccharomyces cerevisiae and are found in all eukaryotes. Components of the unit, soluble N-ethylmaleimidesensitive fusion protein attachment protein receptor (SNARE), function in the plant genetic model Arabidopsis thaliana during its defense to shoot pathogens. Regarding defense, little is understood about SNARE in roots or its regulation. Experiments in Glycine max (soybean) have provided an opportunity to perform such studies, revealing that SNARE genes are expressed under natural conditions in root cells undergoing defense to parasitism by the nematode Heterodera glycines. Presented here, the G. max homolog of S. cerevisiae suppressor of sec1 (SSO1), identified genetically in A. thaliana as PENETRATION1 (PEN1) and named in its genomic annotation as syntaxin 121 (SYP121) functions in the resistance of G. max to H. glycines. Genetic experiments demonstrate Gm- SYP121 is co-expressed with homologs of other SNARE genes exhibiting measurable transcript levels in infected cells undergoing resistance. These genes include synaptosomal-associated protein 25, homologous to A. thaliana SNAP33 (SNAP-25/SNAP33/SEC9); mammalian uncoordinated-18 (MUNC18/SEC1); synaptotagmin/tricalbin-3 (SYT/TCB3); synaptobrevin/vesicle associated membrane protein/YKT6/SEC22 (SYB/VAMP/YKT6/SEC22); N-ethylmaleimide-sensitive fusion protein (NSF/SEC18) and alpha-soluble N-ethylmaleimide-sensitive fusion protein associated protein (a-SNAP/SEC17). Experiments show each SNARE component functions in resistance. In contrast, a coatomer zeta/ retrieval3 (C?/RET3) homolog known to function in retrograde transport within and between the Golgi and endoplasmic reticulum does not appear to function in resistance. Experiments show that SNARE is co-regulated along with a β-glucosidase having homology to PEN2 and an ATP binding cassette transporter exhibiting homology to PEN3. [ABSTRACT FROM AUTHOR]