Kinase‐dead mutation: A novel strategy for improving soybean resistance to soybean cyst nematode Heterodera glycines

Abstract

Protein kinases phosphorylate proteins for functional changes and are involved in nearly all cellular processes, thereby regulating almost all aspects of plant growth and development, and responses to biotic and abiotic stresses. We generated two independent co‐expression networks of soybean genes using control and stress response gene expression data and identified 392 differentially highly interconnected kinase hub genes among the two networks. Of these 392 kinases, 90 genes were identified as “syncytium highly connected hubs”, potentially essential for activating kinase signalling pathways in the nematode feeding site. Overexpression of wild‐type coding sequences of five syncytium highly connected kinase hub genes using transgenic soybean hairy roots enhanced plant susceptibility to soybean cyst nematode (SCN; Heterodera glycines) Hg Type 0 (race 3). In contrast, overexpression of kinase‐dead variants of these five syncytium kinase hub genes significantly enhanced soybean resistance to SCN. Additionally, three of the five tested kinase hub genes enhanced soybean resistance to SCN Hg Type 1.2.5.7 (race 2), highlighting the potential of the kinase‐dead approach to generate effective and durable resistance against a wide range of SCN Hg types. Subcellular localization analysis revealed that kinase‐dead mutations do not alter protein cellular localization, confirming the structure–function of the kinase‐inactive variants in producing loss‐of‐function phenotypes causing significant decrease in nematode susceptibility. Because many protein kinases are highly conserved and are involved in plant responses to various biotic and abiotic stresses, our approach of identifying kinase hub genes and their inactivation using kinase‐dead mutation could be translated for biotic and abiotic stress tolerance.

The soybean immune receptor GmBIR1 regulates host transcriptome, spliceome, and immunity during cyst nematode infection

“…Protein localization of kinase‐dead (KD) and wild‐type (WT) forms of the soybean ( Glycine max L.) BIR1 ( GmBIR1 , Glyma.16G079200 ) was determined in onion epidermal cells. The KD‐GmBIR1 variant was created by replacing the highly conserved lysine residues in the ATP binding pocket (lysine 330) and substrate binding motif (lysine 430) by arginine as previously described (Hewezi et al ., 2015; Piya et al ., 2022). Both variants were synthesized and fused to the N‐terminus of an enhanced yellow fluorescent protein (eYFP) driven by the CaMV 35S promoter in the pSAT6‐EYFP‐N1 vector.…”

“…The newly hatched second‐stage juvenile (J2) penetrates soybean roots and migrates intracellularly to the vascular cylinder where the nematode transforms root cells into a large multinucleate feeding structure known as syncytium from which the nematode feeds and develops into adult male or female. A soybean homolog of BIR1 ( GmBIR1 , Glyma.16G079200 ) has been recently identified as a syncytium highly interconnected kinase hub gene showing high number of gene co‐expression events with a potential role in establishing soybean interaction with SCN (Piya et al ., 2022). Here, we report on the function of GmBIR1 as a negative regulator of defense signaling during SCN parasitism of soybean and the underlying mechanism of action.…”

Overexpression of soybean GmNAC19 and GmGRAB1 enhances root growth and water-deficit stress tolerance in soybean

“…Agrobacterium rhizogenes strain K599 was used for the generation of the soybean hairy roots as previously described ( Rambani et al., 2020a ; Rambani et al., 2020b ; Piya et al., 2022 ). The individual target genes cloned into the pG2RNAi2 binary vector and the empty pG2RNAi2 vector were transferred into A. rhizogenes by the freeze-thaw method.…”

Progress and Challenges in Elucidating the Functional Role of Effectors in the Soybean-Phytophthora sojae Interaction

“…The hairy root technique has been exploited to study the soybean- P. sojae interaction [ 98 , 99 , 100 , 101 ]. Hairy roots are neoplastic growth that forms following infection with the symbiotic bacterium Agrobacterium rhizogenes.…”