Collaborative Research: Unveiling the molecular mechanism of feeding tube formation by root-knot nematodes: structural and functional insights

University Of Georgia Research Foundation Inc, Athens GA

Investigators

Abstract

There is an urgent agricultural need for novel approaches to combat the billions of dollars lost annually to the devastating root-knot nematode, a soilborne roundworm and global threat to food and fiber crop production. Sedentary adult nematode females, which require intensive nourishment for several weeks during the production of hundreds of eggs, feed from plant root cells transformed into giant-cells. Nematode feeding and survival rely on a unique nematode-derived structure called the feeding tube. While the feeding tube has been described at the ultrastructural level, its composition and mechanism of assembly remains an enigma. This project will resolve the mystery of how the root-knot nematode feeding tube is assembled and determine its composition using a combination of immunohistochemistry, structural biology, protein interaction, and gene silencing. The overall goal is to identify the nematode proteins involved in feeding tube formation and translate this knowledge to develop novel root-knot nematode resistance in crop plants. The project will partner with the State Botanical Garden of Georgia for public service and outreach, targeting K-5 students. Through a series of field trips and summer camp activities promoting hands-on activities and interactions with graduate and undergraduate students, the project will bring awareness to the hidden enemies lurking below ground that impact our food supply. This project will support undergraduate and graduate student training. The composition of nematode feeding tubes and the underlying mechanism of their assembly is currently unknown and presents a truly transformative opportunity for a deeper understanding of root-knot nematode parasitism. The basis of this proposal is several novel root-knot nematode proteins that are linked to feeding tube formation. These proteins are produced in the secretory gland cell and actively secreted by feeding adult females. The underlying hypothesis is that once adult root-knot nematode females have established giant-cells, they secrete one or more proteins through their stylet, which self-assemble into a feeding tube essential for efficient nutrient uptake. The project will test this hypothesis by localizing the secreted proteins to the feeding tube, elucidate the 3D structure/s of feeding tube protein(s), test for potential protein interactions to understand the molecular mechanism of feeding tube assembly, and silence encoding genes to disrupt their formation and assess impacts on parasitism. A molecular and biochemical understanding of the mechanism of feeding tube formation will enable the development of innovative, broad-spectrum biotechnology for combating this destructive agricultural pathogen. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.