Table 2 The plant defense-related genes that have been manipulated to enhance sheath blight resistance in rice
| Â | Promoters/Transformation methods | Resistance phenotype | References | |
|---|---|---|---|---|
Name | Functions | |||
OsCHI11 | The chitinases are chitin-degrading enzymes that hydrolyze the β-(1, 4) linkages of chitin. | The maize ubiquitin promoter or CaMV35S promoter, A. tumefaciens-mediated transformation or protoplast transformation | The transgenic plants overexpressing OsCHI11 exhibit enhanced resistance to sheath blight. | Lin et al. (1995) Baisakh et al. (2001) Kumar et al. (2003) Sridevi et al. (2003) Sridevi et al. (2008) Sripriya et al. (2008) |
OsRC7 | The chitinase gene (OsRC7) encodes a class I chitinase (PR3 family) in rice. | The CaMV35S promoter, the biolistic method and protoplast transformation | The transgenic plants overexpressing the chitinase show different levels of enhanced resistance to R. solani. | Datta et al. (2001) |
Os11g47510 | A novel chitinase gene from indica rice | The CaMV35S promoter, the biolistic method | The transgenic plants show good correlation between transgene expression and the level of sheath blight resistance. | Richa et al. (2017) |
Ace-AMP1 | Ace-AMP1, a cysteine rich antimicrobial peptide from Allium cepa, is homologous to plant ns-LTP and shows strong antimicrobial activity. | An inducible rice phenylalanine ammonia-lyase (PAL) promoter or a constitutive maize ubiquitin promoter, A. tumefaciens-mediated transformation | The transgenic plants exhibit increased resistance to blast, sheath blight, and bacterial leaf blight without agronomic trait penalty. | Patkar and Chattoo (2006) |
Dm-AMP1 | Dm-AMP1, an antifungal plant defensin from Dahlia merckii, directly inhibits the pathogen. | The maize ubiquitin promoter, A. tumefaciens-mediated transformation | The transgenic rice plants expressing Dm-AMP1 have the potential to provide broad-spectrum disease resistance in rice. | Jha et al. (2009) |
Rs-AFP2 | Rs-AFP2, an antifungal plant defensin from Raphanus sativus, directly inhibits the pathogen. | The maize ubiquitin promoter, A. tumefaciens-mediated transformation | The transgenic rice plants expressing Rs-AFP2 show enhanced resistance to M. oryzae and R. solani. | Jha and Chattoo |
OsWRKY30 | WRKY30 activates expression of JA synthesis-related genes LOX, AOS2 and pathogenesis-related PR3 and PR10 genes | The maize ubiquitin promoter, A. tumefaciens-mediated transformation | The transgenic lines overexpressing WRKY30 have an enhanced resistance to R. solani. | Peng et al. (2012) |
OsWRKY80 | OsWRKY80 activates OsWRKY4 expression, and subsequently activates JA/ET-dependent defense responses. | The maize ubiquitin promoter, A. tumefaciens-mediated transformation | Overexpression of OsWRKY80 in rice plants significantly enhances disease resistance to R. solani, while silencing of OsWRKY80 compromises disease resistance to R. solani. | Peng et al. (2016) |
OsACS2 | OsACS2,1-aminocyclopropane-1-carboxylic acid synthase, is a key enzyme of ET biosynthesis. | The pathogen-inducible PBZ1 promoter, A. tumefaciens-mediated transformation | The OsACS2-overexpression lines show significantly increased levels of endogenous ET and defence gene expression, increased resistance to R. solani and M. oryzae, with little or no influence on seed production. | Helliwell et al. (2013) |
AtNPR1 | Nonexpresser of pathogenesis-related gene 1 (NPR1) in Arabidopsis as the master regulator of salicylic acid-mediated signaling | The CaMV35S promoter, A. tumefaciens-mediated transformation | Green tissue-specific expression of AtNPR1 in rice confers resistance to sheath blight, with no concomitant abnormalities in plant growth and yield parameters. | Molla et al. (2016) |
BjNPR1 | Brassica juncea nonexpresser of pathogenesis-related gene 1 (BjNPR1) causes redox-regulation in mustard akin to that of AtNPR1 in Arabidopsis. | The CaMV35S promoter, A. tumefaciens-mediated transformation | The BjNPR1-expressing rice lines display enhanced resistance to rice blast, sheath blight and bacterial leaf blight diseases, and improved agronomic traits. | Sadumpati et al.(2013) |
OsOSM1 | Osmotins belong to thaumatin-like proteins of PR5 family and are involved in the permeability stress and defense response in plants | The maize ubiquitin promoter, A. tumefaciens-mediated transformation | An appropriately elevated level of OsOSM1 in transgenic rice enhances RSB resistance without affecting rice development or grain yield. | Xue et al. (2016) |
OsOXO4 and OsCHI11 | As mentioned above | The green tissue-specific rice D54O-544 promoter and maize PEPC promoter, A. tumefaciens-mediated transformation | Simultaneous overexpression of the defense-related genes OsCHI11 and OsOXO4 in rice leads to significant resistance against R. solani without distressing any agronomically important traits. | Karmakar et al.(2015) |
AtNPR1 and OsCHI11 | As mentioned above | The green tissue-specific rice D54O-544 promoter and maize PEPC promoter, A. tumefaciens-mediated transformation | The transgenic rice plants with simultaneous overexpression of AtNPR1 and OsCHI11 show a significant upregulation of defense-related genes, PR genes, and antioxidant marker genes, and are more resistant to sheath blight as compared to the single transgene. | Karmakar et al.(2017) |
OsMAPK20-5 | Mitogen-activated protein kinases (MAPKs) play important roles in plant responses to biotic stresses. | Silencing of OsMAPK20-5 by inserting an inverted-repeat orientation (irMAPK20-5) A. tumefaciens-mediated transformation | Silencing of OsMAPK20-5 causes rice plants more susceptibility to Cnaphalocrocis medinalis and Magnaporthe grisea, but enhances sheath blight resistance. | Liu et al. (2019) |
OsGSTU5 | OsGSTU5 is a tau class of glutathione-S-transferase in rice, an important defense-associated protein that confers resistance against several abiotic and biotic stresses. | Via the expression vector pIRS154, A. tumefaciens-mediated transformation | The OsGSTU5-overexpressing rice lines are more tolerant, while the knockdown lines are more prone to Rhizoctonia infection. | Tiwari et al. (2020) |
OsASR2 | OsASR2 (abscisic acid, stress and ripening 2) regulates the expression of a defense-related gene, Os2H16, by targeting the GT-1 cis-element. | Maize Ubiquitin 1 promoter, A. tumefaciens-mediated transformation | Overexpression of OsASR2 enhances the resistance against Rhizoctonia solani and tolerance to drought in rice. | Li et al. (2018) |
LPA1 | LPA1 belongs to an INDETERMINATE DOMAIN protein family and regulates sheath blight resistance, tiller and leaf angle by activating auxin signaling. | Maize Ubiquitin 1 promoter, A. tumefaciens-mediated transformation | Overexpression of LPA1 and IDD13 enhances rice defenses against sheath blight via the activation of PIN1a in rice. | Sun et al. (2019) |
DEP1 | DEP1, a G-protein γ subunit, is a novel interactor of LPA1 and controls dense and erect panicle of rice. | The knock-out mutant dep1 (PFG_3A-02648) was generated with T-DNA insertion. | DEP1 knock-out increases planting density and resistance to sheath blight disease in rice. | Liu et al. (2020) |