A Malaria Type Effector in the Soybean Cyst Nematode Modulates the Plant Immune System

Thumbnail Image
Andrews, Danielle
Major Professor
Committee Member
Journal Title
Journal ISSN
Volume Title
Research Projects
Organizational Units
Organizational Unit
Journal Issue
Is Version Of
Symposium on Undergraduate Research and Creative Expression
Iowa State University Conferences and Symposia

The Symposium provides undergraduates from all academic disciplines with an opportunity to share their research with the university community and other guests through conference-style oral presentations. The Symposium represents part of a larger effort of Iowa State University to enhance, support, and celebrate undergraduate research activity.

Though coordinated by the University Honors Program, all undergraduate students are eligible and encouraged to participate in the Symposium. Undergraduates conducting research but not yet ready to present their work are encouraged to attend the Symposium to learn about the presentation process and students not currently involved in research are encouraged to attend the Symposium to learn about the broad range of undergraduate research activities that are taking place at ISU.

The first Symposium was held in April 2007. The 39 students who presented research and their mentors collectively represented all of ISU's Colleges: Agriculture and Life Sciences, Business, Design, Engineering, Human Sciences, Liberal Arts and Sciences, Veterinary Medicine, and the Graduate College. The event has grown to regularly include more than 100 students presenting on topics that span the broad range of disciplines studied at ISU.

Plant Pathology and Microbiology

Cyst nematodes (CNs) are sedentary endoparasitic round worms that infect the roots of economically important plants such as soybean, potato and sugar beet. CNs secrete proteins (effectors) into root tissues and cells to promote parasitism. Sequence analyses of one CN effector determined that it has marginal, but significant similarity to an effector found only in the Malaria parasites (Plasmodium spp.), the Circumsporozoite Protein (CSP). Furthermore, the CN effector and Plasmodium CSPs share four protein domains that are essential for CSP function inside animal cells. Numerous evidences indicate that Plasmodium CSPs suppress the immune systems of their animal hosts by multiple, diverse strategies. As plants have immune systems, with significant overlaps with the animal innate immune system, we performed assays to test whether the CN effector suppresses plant immunity. Remarkably, multiple lines of evidence indicate that the CN effector strongly suppresses both of the major routes of the plant immune system. We are currently testing whether a CSP from the monkey Malaria species, P. fieldi, which the CN effector is most similar to, also suppresses plant immunity. We hypothesize that the CN effector and CSPs have converged on similar sequences to execute similar functions in their plant and animal hosts, respectively.