Host–Pathogen Interaction in Fusarium oxysporum Infections: Where Do We Stand?

Abstract

Fusarium oxysporum, a ubiquitous soilborne pathogen, causes devastating vascular wilt in more than 100 plant species and ranks 5th among the top 10 fungal plant pathogens. It has emerged as a human pathogen, too, causing infections in immune-compromised patients. Therefore, it is important to gain insight into the molecular processes involved in the pathogenesis of this transkingdom pathogen. A complex network comprising interconnected and overlapping signal pathways-mitogen-activated protein kinase signaling pathways, Ras proteins, G-protein signaling components and their downstream pathways, components of the velvet (LaeA/VeA/VelB) complex, and cAMP pathways-is involved in perceiving the host. This network regulates the expression of various pathogenicity genes. However, plants have evolved an elaborate protection system to combat this attack. They, too, possess intricate mechanisms at the molecular level which, once triggered by pathogen attack, transduce signals to activate defense response. This review focuses on understanding and presenting a wholistic picture of the molecular mechanisms of F. oxysporum-host interactions in plant immunity.

Breeding, Genetics, and Genomics Approaches for Improving Fusarium Wilt Resistance in Major Grain Legumes

“…Following establishment of the pathogen on plant roots, root penetration, and hyphal propagation of the FW pathogen causes a compromise in the host defense system (for detail see Rep and Kistler, 2010;Srinivas et al, 2019). At molecular level, the fungal pathogen recognizes a particular host and produces a range of cell wall-degrading enzymes including cellulases, pectinases, polygalacturonases, etc., in response to host plant derived hydrolases (viz., chitinase, glucanases) (Michielse et al, 2009;Swarupa et al, 2014;Husaini et al, 2018). Besides, the FW pathogen is also known to produce various mycotoxins/phytotoxins viz., fusaric acid (FSA), beauvericin, and enniatins in banana (López-Díaz et al, 2017;Liu et al, 2020;Shao et al, 2020).…”

“…Besides, the FW pathogen is also known to produce various mycotoxins/phytotoxins viz., fusaric acid (FSA), beauvericin, and enniatins in banana (López-Díaz et al, 2017;Liu et al, 2020;Shao et al, 2020). In parallel, the attacking pathogen integrates various signal transduction pathways mediated by mitogen activated protein (MAP) kinase cascades that transduce the signal downstream to the intracellular targets in response to the signal perceived by various receptors at cell surface during host infection (Widmann et al, 1999;Husaini et al, 2018). Thus, MAP plays a key role in regulating FW pathogenicity.…”

“…Thus, MAP plays a key role in regulating FW pathogenicity. Several genes are known to regulate host colonization and pathogenicity, which include FWO1 (Inoue et al, 2002), ClcI (Cañero and Roncero, 2008), chitin synthase V, DCW1, mannose-6-phosphate isomerase gene, FOXG_11097 (Michielse et al, 2009), XlnR (Calero-Nieto et al, 2007), secreted in xylem (SIX) protein encoding genes (Thatcher et al, 2016), SIX1, SIX6, and FTF1 genes (Ninþo-Saìnchez et al, 2015) (for details see Husaini et al, 2018). Thus, successful disease occurrence by the FW pathogen demands a compromise in the plant defense system.…”

Pathogenomics Characterization of an Emerging Fungal Pathogen, Fusarium oxysporum f. sp. lycopersici in Greenhouse Tomato Production Systems

“…SIX1, SIX3, SIX4, SIX5 , and SIX6 have all been shown to make a direct contribution to virulence ( Rep, 2005 ; Houterman et al, 2009 ; Takken and Rep, 2010 ; Thatcher et al, 2012 ; Gawehns et al, 2014 ; Ma et al, 2015 ). Interestingly, some of these genes can also evade host immunity by suppressing R gene-mediated resistance ( Jones and Dangl, 2006 ; Husaini et al, 2018 ). For example, SIX1 contributes directly to root penetration and invasion of xylem vessels ( Rep et al, 2004 , 2005 ; van der Does et al, 2008 ; Ma et al, 2010 ).…”

“…Fifteen pathogenicity genes involved in signaling pathways, cell-wall degradation, and transcriptional factors regulating gene expression and conferring virulence to F. oxysporum ( Idnurm and Howlett, 2001 ; Husaini et al, 2018 ) and described previously in other F. oxysporum f. spp. ( Covey et al, 2014 ; Ellis et al, 2016 ) were examined.…”