A sorghum BAK1/SERK4 homolog functions in pathogen-associated molecular patterns-triggered immunity and cell death in response to Colletotrichum sublineola infection

Authors: VELA, SADDIE - University Of Florida; WOLF, EMILY - University Of Florida; ZHOU, MINGXI - University Of Florida; DAVIS, ALYSSA - University Of Florida; MOU, ZHONGLIN - University Of Florida; Cuevas, Hugo; VERMERRIS, WILFRED - University Of Florida

Submitted to: Phytopathology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/3/2025
Publication Date: 4/25/2025
Citation: Vela, S., Wolf, E.S., Zhou, M., Davis, A., Mou, Z., Cuevas, H.E., Vermerris, W. 2025. A sorghum BAK1/SERK4 homolog functions in pathogen-associated molecular patterns-triggered immunity and cell death in response to Colletotrichum sublineola infection. Phytopathology. 115: 387-400. https://doi.org/10.1094/PHYTO-09-24-0283-R.
DOI: https://doi.org/10.1094/PHYTO-09-24-0283-R

Interpretive Summary: Understanding the molecular mechanism of plant resistance response against pathogens is imperative for the development of new disease control strategies. Thus, the molecular function of the anthracnose (Colletotrichum sublineola) resistance gene Sobic.005G182400 was studied via gene co-expression network and gene regulatory network analysis of transcriptomic data. The results showed this gene has an essential function in the plant immunity system through the activation of multiple defense related genes that cause cell death during the pathogen infection. This work provides new insight for the developing of novel diseases resistance response in different crops.

Technical Abstract: Sorghum bicolor (L.) Moench is the fifth most important cereal crop behind maize, wheat, rice, and barley and is expected to gain prominence due to its versatility, low input requirements, and tolerance to hot and dry conditions. The productivity of sorghum is severely limited by the hemibiotrophic fungal pathogen, Colletotrichum sublineola, which causes anthracnose. Cultivating anthracnose-resistant accessions is the most effective way to safeguard yield. However, the molecular function of resistance loci in sorghum is not well characterized. A previous genome-wide association study for anthracnose resistance in the sorghum association panel (SAP) uncovered novel loci on chromosome 5 associated with resistance to anthracnose disease. One locus consisted of a single nucleotide polymorphism located within the coding region of gene Sobic.005G182400, annotated to encode a tyrosine kinase. We examined the molecular function of Sobic.005G182400 via gene co-expression network and gene regulatory network analysis of transcriptomic data from inoculated versus mock-inoculated samples. Based on our analysis, we determined that Sobic.005G182400 is a homolog of the Arabidopsis thaliana BRASSINOSTEROID INSENSITIVE 1-ASSOCIATED RECEPTOR KINASE1 (BAK1) and Oryza sativa SOMATIC EMBRYOGENESIS RECEPTOR-LIKE KINASE 4 (SERK4). These genes play a role in pathogen-associated molecular pattern (PAMP)-triggered immunity and regulation of cell death by protein glycosylation. Our findings provide insights in the sorghum-C. sublineola interaction, which in turn will facilitate the development of novel strategies to protect sorghum against anthracnose.