Date of Graduation


Document Type


Degree Name

Bachelor of Science in Biology

Degree Level



Biological Sciences


Egan, Martin

Committee Member/Reader

Bailey, Tameka

Committee Member/Second Reader

Lewis, Jeffrey

Committee Member/Third Reader

Davidson, Fiona


The plant pathogenic fungus Magnaporthe oryzae forms a specialized pressure-generating infection cell called an appressorium on the leaf surface, which it uses to mechanically rupture the otherwise impenetrable cuticle, enabling colonization of the underlying tissue and the establishment of blast disease. Appressorium differentiation by M. oryzae is cell cycle-regulated and requires programmed cell death of a three-celled propagative spore, as well as extensive remodeling of the microtubule, actin, and septin cytoskeletons. Recent studies have proposed the importance of sumoylation – the enzymatic conjugation of a small ubiquitin-like modifier to target proteins, for various aspects of infection-related development by M. oryzae, including the formation of septin ring-like structures within the base of appressoria, through direct sumoylation of four core septin proteins. Here, using fluorescence microscopy-based live-cell imaging of sumoylation-deficient M. oryzae mutants, we determine the importance of global sumoylation for key stages of appressorium morphogenesis in vitro, including nuclear division and the formation and remodeling of higher-order septin structures. Together, our data provide new perspective on the importance of sumoylation for infection-related development by the blast fungus.


sumoylation, Uba2, septins, cell cycle

Available for download on Thursday, May 01, 2025