Transcriptome and Oxylipin Profiling Joint Analysis Reveals Opposite Roles of 9-Oxylipins and Jasmonic Acid in Maize Resistance to Gibberella Stalk Rot

Abstract

Gibberella stalk rot caused by Fusarium graminearum is one of the devastating diseases of maize that causes significant yield losses worldwide. The molecular mechanisms regulating defense against this pathogen remain poorly understood. According to recent studies, a major oxylipin hormone produced by 13-lipoxygenases (LOX) namely jasmonic acid (JA) has been associated with maize susceptibility to GSR. However, the specific roles of numerous 9-LOX-derived oxylipins in defense against Gibberella stalk rot (GSR) remain unexplained. In this study, we have shown that disruption of a 9-LOX gene, ZmLOX5, resulted in increased susceptibility to GSR, indicating its role in defense. To understand how ZmLOX5 regulates GSR resistance, we conducted transcriptome and oxylipin profiling using a zmlox5-3 mutant and near-isogenic wild type B73, upon infection with F. graminearum. The results showed that JA biosynthetic pathway genes were highly up-regulated, whereas multiple 9-LOX pathway genes were down-regulated in the infected zmlox5-3 mutant. Furthermore, oxylipin profiling of the mutant revealed significantly higher contents of several jasmonates but relatively lower levels of 9-oxylipins in zmlox5-3 upon infection. In contrast, B73 and W438, a more resistant inbred line, displayed relatively lower levels of JAs, but a considerable increase of 9-oxylipins. These results suggest antagonistic interaction between 9-oxylipins and JAs, wherein 9-oxylipins contribute to resistance while JAs facilitate susceptibility to F. graminearum.

Comparative transcriptome profiling and weighted gene co-expression network analysis to identify core genes in maize (Zea mays L.) silks infected by multiple fungi

“…The rationality variation in the value of the DEGs seemed to be caused by fungal infection ( Yang et al., 2022 ), and this perhaps could be reasoned out with the differences observed in the sample sizes of the datasets, where the control of dataset A (Ca) had 7.5 GB, while the control of dataset B (Cb) had 2.5 GB. The concept well defends this examination that varied sample sizes and the spatiotemporal specificity of samples could influence the drastic variations in the different data sets ( Wang, et al., 2021 ).…”

“…A research team ( Horst et al., 2008 ) proposed that Um infection to Z. mays leaves reduced the photosynthetic rate and maintained the nutrients as well as influenced the chlorophyll content on a time scale ( Kshirsagar et al., 2001 ). Wang et al. (2021) proposed the light harvesting in photosystem 1, a biosynthetic/metabolic process positively expressed in Gibberella stalk rot disease in Z. mays plant.…”

Convergent Gene Expression Patterns During Compatible Interactions Between TwoPseudomonas syringaePathovars and a Common Host (Nicotiana benthamiana)

“…The most upregulated gene with the chloroplast envelope GO term is a 9-divinyl ether synthase (DES; NbD030668); under biotic stress, related proteins can form antimicrobial oxylipins that have been found to be more useful against eukaryotic pathogens (Prost et al 2005). For example, NtDES1 from N. tabacum is upregulated in the early response to a pathogenic oomycete, while other oxylipin synthesis genes have roles in defense against nematode and fungal infections (Fammartino et al 2007; Wang et al 2021; Sanadhya et al 2021). In contrast, the most downregulated gene with the chloroplast envelope GO term is a receptor-like kinase (NbD047510) from the THESEUS 1/FERONIA family that can serve to detect cell wall defects and damage (Cheung and Wu 2011); this gene is annotated with additional GO terms associated with other cellular membranes, indicating unclear predicted localization.…”

A non‐JA producing oxophytodienoate reductase functions in salicylic acid‐mediated antagonism with jasmonic acid during pathogen attack

“…These results, once again, provided solid genetic evidence for JA as a susceptibility factor in maize– C. graminicola interactions. Similarly, recent studies of the interactions between maize and F. graminearum provided strong evidence based on the transcriptome, metabolome, and functional analyses of lox5 , opr7opr8 , and JAZ mutants that JA contributes to disease progression against this hemibiotrophic pathogen (Ma et al, 2021 ; Sugimoto et al, 2022 ; Wang et al, 2021 ).…”