Title:Recent Advances in the Study of the Plant Pathogenic Fungus Botrytis cinerea and its Interaction with the Environment
Volume: 18
Issue: 10
Author(s): Luis Castillo*, Verónica Plaza, Luis F. Larrondo and Paulo Canessa
Affiliation:
- Laboratory of Biochemistry and Molecular Biology, Department of Biology, Faculty of Sciences, University of La Serena, La Serena,Chile
Keywords:
Botrytis cinerea, cell wall, virulence factor, cell wall-degrading enzymes, light, circadian clock.
Abstract: The primary contact between the fungal phytopathogen Botrytis cinerea and its host takes
place at the cell surface of both organisms. The fungal cell wall is generally composed of an inner
skeletal layer consisting of various polysaccharides surrounded by a layer of glycoproteins. Some of
these glycoproteins have structural or enzymatic functions, or are involved in conidial adhesion. After
landing on the host surface and sensing appropriate signals, B. cinerea conidia produce a germ tube
and secrete phytotoxic fungal metabolites and cell wall-degrading enzymes (CWDEs), facilitating
host penetration. In fact, 118 genes encoding putative Carbohydrate-Active Enzymes (CAZymes)
have been identified in the B. cinerea genome. This large enzymatic repertoire could explain, at least
in part, the ability of B. cinerea to infect a vast number of plant species. In recent years, several genes
and signaling factors have been identified as playing key roles in pathogenesis, particularly in appressorium
formation and penetration. These include the NOX Complex, MAPK cascades, heterotrimeric
G proteins, histidine kinases and cAMP signaling pathways. Some of these pathways could also be
responsible for controlling the expression and secretion of CWDEs and/or secondary metabolites during
infection. Herein, putative virulence factors that are linked to the cell wall, as well as recentlydescribed
genes and components that allow the sensing of environmental cues, are highlighted.
