The cysteine-rich receptor-like kinase TaCRK3 contributes to defense against Rhizoctonia cerealis in wheat

Abstract

Sharp eyespot, caused by the necrotrophic fungal pathogen Rhizoctonia cerealis, is a devastating disease of bread wheat (Triticum aestivum). However, the molecular mechanisms underlying wheat defense against Rhizoctonia cerealis are still largely unknown. In this study, we identified a novel cysteine-rich receptor-like kinase (CRK)-encoding gene, designated as TaCRK3, through comparative transcriptomic analysis, and investigated its defence role against Rhizoctonia cerealis. TaCRK3 transcriptional abundance was significantly elevated by R. cerealis and exogenous ethylene treatments. Silencing of TaCRK3 significantly compromised resistance to R. cerealis and repressed expression of an ethylene biosynthesis enzyme-encoding gene ACO2 and a subset of defence-associated genes in wheat, whose transcript levels are up-regulated by ethylene stimulus. TaCRK3 protein was localized at the plasma membrane in wheat. Noticeably, both the heterologously-expressing TaCRK3 protein and its partial peptide harboring two DUF26 domains could inhibit growth of R. cerealis mycelia. These results suggest that the TaCRK3 mediates wheat resistance to R. cerealis through direct-antifungal activity and heightening the expression of defence-associated genes in the ethylene signaling pathway, and that its DUF26 domains are required for the antifungal activity of TaCRK3. This study provides a promising gene for breeding wheat varieties with resistance to R. cerealis.

TaWAK2A-800, a Wall-Associated Kinase, Participates Positively in Resistance to Fusarium Head Blight and Sharp Eyespot in Wheat

“…Four wheat cultivars/varieties, including R. cerealis -resistant CI12633 (Prof. Shibing Cai, Jiangsu Academy of Agricultural Sciences, Nanjing, Jiangsu, China), and Shanhongmai (Prof. Jizeng Jia, Institute of Crop Sciences, CAAS, Beijing, China), R. cerealis -susceptible Yangmai 9 (Prof. Jizeng Jia), and Wenmai 6 (Prof. Shunhe Cheng, Jiangsu Academy of Agricultural Sciences, Nanjing, Jiangsu, China) [ 36 ], were used to investigate the transcriptional profile of TaWAK2A-800 . The sharp-eyespot-resistant and -susceptible recombinant RILs (derived from Shanhongmai and Wenmai 6 cross) were used for RNA-sequencing, and RNA-sequencing analyses were performed as described by Guo et al [ 37 ]. The R. cerealis -resistant cultivar, CI12633, and the F. graminearum -resistant cultivar, Sumai 3 (Prof. Jizhong wu, Jiangsu Academy of Agricultural Sciences, Nanjing, Jiangsu, China), were used to detect the defense role of TaWAK2A-800 against R. cerealis and F. graminearum by the virus-induced gene-silencing (VIGS) experiment, respectively.…”

“…Then, these spikes of Sumai 3 were placed in a plastic moist chamber, with high humidity, at 22 °C for 2 days. The RNA-sequencing-based transcriptomics of TaWAK2A-800 ( Table S1 ) were subjected as described by Guo et al [ 37 ].…”

“…The transcriptional levels of TaWAK2A-800 ( TaWAK2A-800 -QF: 5′-GGTATCGTGCTACTGGAGCTC-3′, TaWAK2A-800 -QR: 5′-CTCCCATGGTAGGC CTGTTA-3′), TaRLCK1B [ 40 ], TaCERK1 ( TaCERK1 -QF: 5′-CGGAGCAGATGGAC ACACTT-3′, TaCERK1 -QR: 5′-TGAGTGGCCGATGATGTCAC-3′), TaMPK3 [ 41 ], Defensin [ 41 ], Chitinase 3 [ 37 ], and β-1,3-Glucanase [ 37 ] in wheat were measured and analyzed using RT-PCR or qRT-PCR. Following the previous method [ 37 ], the qRT-PCR reaction was performed by using a SYBR Premix Ex Taq kit (TaKaRa, Otsu, Japan), in volumes of 20 μL, on an ABI 7500 RT-PCR system (Applied Biosystems, Waltham, MA, USA). The 2 −ΔΔCT method [ 42 ] was used to calculate the relative transcription level of the target genes (internal reference: TaActin ).…”

“…TraesCS2A02G071800.1 was downloaded from the Chinese Spring V1.0 genome (http://202.194.139.32/jbrowse.html, accessed on 27 February 2020). The deduced protein sequence of TaWAK2A-800 and the phylogenetic tree were obtained and constructed as described by Guo et al [37].…”

The Wheat Wall-Associated Receptor-Like Kinase TaWAK-6D Mediates Broad Resistance to Two Fungal Pathogens Fusarium pseudograminearum and Rhizoctonia cerealis

“…In this study, the recombinant inbred lines (RILs) derived from the cross Shanhongmai × Wenmai 6, were used for RNA-Seq (RNA-sequencing) analysis as described by Zheng et al ( 2020 ) and Guo et al ( 2021 ).…”