Conidial Morphogenesis and Septin-Mediated Plant Infection Require Smo1, a Ras GTPase-Activating Protein in Magnaporthe oryzae

Kershaw, Michael J., Basiewicz, Magdalena, Soanes, Darren M., Yan, Xia, Ryder, Lauren S., Csukai, Michael, Oses-Ruiz, Miriam, Valent, Barbara and Talbot, Nicholas J. (2019) Conidial Morphogenesis and Septin-Mediated Plant Infection Require Smo1, a Ras GTPase-Activating Protein in Magnaporthe oryzae. Genetics, 211 (1). pp. 151-167. ISSN 0016-6731

[img]
Preview
PDF (Published_Version) - Published Version
Available under License Creative Commons Attribution.

Download (2MB) | Preview

Abstract

The pathogenic life cycle of the rice blast fungus Magnaporthe oryzae involves a series of morphogenetic changes, essential for its ability to cause disease. The smo mutation was identified > 25 years ago, and affects the shape and development of diverse cell types in M. oryzae, including conidia, appressoria, and asci. All attempts to clone the SMO1 gene by map-based cloning or complementation have failed over many years. Here, we report the identification of SMO1 by a combination of bulk segregant analysis and comparative genome analysis. SMO1 encodes a GTPase-activating protein, which regulates Ras signaling during infection-related development. Targeted deletion of SMO1 results in abnormal, nonadherent conidia, impaired in their production of spore tip mucilage. Smo1 mutants also develop smaller appressoria, with a severely reduced capacity to infect rice plants. SMO1 is necessary for the organization of microtubules and for septin-dependent remodeling of the F-actin cytoskeleton at the appressorium pore. Smol physically interacts with components of the Ras2 signaling complex, and a range of other signaling and cytoskeletal components, including the four core septins. SMO1 is therefore necessary for the regulation of RAS activation required for conidial morphogenesis and septin-mediated plant infection.

Item Type: Article
Uncontrolled Keywords: magnaporthe oryzae,pyricularia oryzae,rice blast,smo,ras-gap,bulked segregant analysis,rice blast fungus,surface attachment,map kinase,identification,grisea,norwich,encodes,biology,genome,growth
Faculty \ School:
Depositing User: LivePure Connector
Date Deposited: 15 Feb 2019 09:30
Last Modified: 18 Mar 2020 02:38
URI: https://ueaeprints.uea.ac.uk/id/eprint/69933
DOI: 10.1534/genetics.118.301490

Actions (login required)

View Item View Item