AUTHOR=Yang Tiantian , Liu Jiajun , Li Xiaomei , Amanullah Sikandar , Lu Xueyan , Zhang Mingchong , Zhang Yanhang , Luan Feishi , Liu Hongyu , Wang Xuezheng 

TITLE=Transcriptomic Analysis of Fusarium oxysporum Stress-Induced Pathosystem and Screening of Fom-2 Interaction Factors in Contrasted Melon Plants

JOURNAL=Frontiers in Plant Science

VOLUME=Volume 13 - 2022

YEAR=2022

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2022.961586

DOI=10.3389/fpls.2022.961586

ISSN=1664-462X

ABSTRACT=<p>Fusarium wilt is one of the most destructive and less controllable diseases in melon, which is usually caused by <italic>fusarium oxysporum</italic>. In this study, transcriptome sequencing and Yeast Two-Hybrid (Y2H) methods were used for quantification of differentially expressed genes (DEGs) involved in <italic>fusarium oxysporum</italic> (f. sp. <italic>melonis</italic> race 1) stress-induced mechanisms in contrasted melon varieties (M4-45 “susceptible” and MR-1 “resistant”). The interaction factors of <italic>Fom-2</italic> resistance genes were also explored in response to the plant-pathogen infection mechanism. Transcriptomic analysis exhibited total 1,904 new genes; however, candidate DEGs analysis revealed a total of 144 specific genes (50 upregulated and 94 downregulated) for M4-45 variety and 104 specific genes (71 upregulated and 33 downregulated) for MR-1 variety, respectively. The analysis of Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway depicted some candidate DEGs, including Phenylalanine metabolism, phenylpropane biosynthesis, plants-pathogen interaction, and signal transduction of plant hormones, which were mainly involved in disease resistance metabolic pathways. The weighted gene co-expression network analysis (WGCNA) analysis revealed a strong correlation module and exhibited the disease resistance-related genes encoding course proteins, transcription factors, protein kinase, benzene propane biosynthesis path, plants-pathogen interaction pathway, and glutathione S-transferase. Meanwhile, the resistance-related specific genes expression was relatively abundant in MR-1 compared to the M4-45, and cell wall-associated receptor kinases (<italic>MELO3C008452</italic> and <italic>MELO3C008453</italic>), heat shock protein (Cucumis_melo_newGene_172), defensin-like protein (Cucumis_melo_newGene_5490), and disease resistance response protein (<italic>MELO3C016325</italic>), activator response protein (<italic>MELO3C021623</italic>), leucine-rich repeat receptor protein kinase (<italic>MELO3C024412</italic>), lactyl glutathione ligase (Cucumis_melo_newGene_36), and unknown protein (<italic>MELO3C007588</italic>) were persisted by exhibiting the upregulated expressions. At the transcription level, the interaction factors between the candidate genes in response to the <italic>fusarium oxysporum</italic> induced stress, and Y2H screening signified the main contribution of MYB transcription factors (<italic>MELO3C009678</italic> and <italic>MELO3C014597</italic>), BZIP (<italic>MELO3C011839</italic> and <italic>MELO3C019349</italic>), unknown proteins, and key enzymes in the ubiquitination process (<italic>4XM334FK014</italic>). The candidate genes were further verified in exogenously treated melon plants with <italic>f. oxysporum</italic> (<italic>Fom-2</italic>, Race 1), Abscisic acid (ABA), Methyl Jasmonite (MeJA), and Salicylic acid (SA), using the fluorescence quantitative polymerase chain reaction (qRT-PCR) analysis. The overall expression results indicated that the SA signal pathway is involved in effective regulation of the <italic>Fom-2</italic> gene activity.</p>