Expression and distribution of extensins and AGPs in susceptible and resistant banana cultivars in response to wounding and Fusarium oxysporum

Abstract

Banana Fusarium wilt caused by Fusarium oxysporum f. sp. cubense (Foc) is soil-borne disease of banana (Musa spp.) causing significant economic losses. Extensins and arabinogalactan proteins (AGPs) are cell wall components important for pathogen defence. Their significance for Foc resistance in banana was not reported so far. In this study, two banana cultivars differing in Foc sensitivity were used to monitor the changes in transcript levels, abundance and distribution of extensins and AGPs after wounding and Foc inoculation. Extensins mainly appeared in the root cap and meristematic cells. AGPs recognized by JIM13, JIM8, PN16.4B4 and CCRC-M134 antibodies located in root hairs, xylem and root cap. Individual AGPs and extensins showed specific radial distribution in banana roots. At the transcript level, seven extensins and 23 AGPs were differentially expressed between two banana cultivars before and after treatments. Two extensins and five AGPs responded to the treatments at the protein level. Most extensins and AGPs were up-regulated by wounding and pathogen inoculation of intact plants but down-regulated by pathogen attack of wounded plants. Main components responsible for the resistance of banana were MaELP-2 and MaPELP-2. Our data revealed that AGPs and extensins represent dynamic cell wall components involved in wounding and Foc resistance.

Infection with blast fungus (Magnaporthe orzyae) leads to increased expression of an arabinogalactan-protein epitope in both susceptible and resistant rice cultivars

“…At the transcript level, seven extensins and 23 AGP genes were differentially expressed between the two banana cultivars before and after treatment. These data revealed that AGPs and extensins are involved in wounding and Fusarium resistance in banana (Wu et al, 2017). These and other recent investigations have linked AGPs to the infectious structures of both beneficial and pathogenic microbes in plant roots (Nguema-Ona et al, 2013).…”

“…Monoclonal antibodies raised against components of the plant extracellular matrix have been shown to provide a powerful 'toolkit' with which to study plant growth and development and stress responses (Roberts, 1989;Knox, 1997;Chen et al, 2006;Cornault et al, 2015). The use of such antibodies has also been applied to the study of plant/pathogen interactions (Xie et al, 2011;Wu et al, 2017). The role of plant cell wall hydroxyproline-rich glycoproteins (HRGPs) in the interaction between wax…”

“…In recent years, the utility of using well-characterised, anti-plant cell wall/plasma membrane antibodies to study plant/pathogen interactions, has shown that they can be used to facilitate an array of techniques (e.g. immunocytochemistry and immunogold labeling) which can be applied to better define modulations in plant cell wall and plasma membrane components in situ within complex tissues (Xie et al, 2011;Nguema-Ona et al, 2013;Wu et al, 2017).…”

“…Amongst the plethora of polysaccharide, glycoprotein and glycolipid components of the plant cell wall and plasma membrane, the importance of members of the hydroxyproline-rich glycoprotein (HRGP) superfamily, has been shown to be of major significance in plant pathogenesis (Wu et al, 2017). Within this superfamily, the potential role(s) of arabinogalactan-proteins (AGPs) is of particular interest.…”

“…Within this superfamily, the potential role(s) of arabinogalactan-proteins (AGPs) is of particular interest. AGPs have been shown to occur both within the plant cell wall and as glycosylphosphatidylinositol (GPI) anchored proteins, located in the plasma membrane and have been demonstrated to play a role in plant -microbe interactions (Xie et al, 2011;Nguema-Ona et al, 2013;Wu et al, 2017).…”