Posted: December 1, 2017

Natali Özber's proposal was selected for funding by College of Agricultural Sciences Graduate Student Competitive Grants Program.

Image: Penn State

Image: Penn State

Ph.D. candidate Natali Özber's proposal titled "Probing the structure and frequency of plasmodesmata via virus infection" was one of fourteen proposals selected for funding by the College of Agricultural Sciences Graduate Student Competitive Grants Program. Natali is a Plant Biology doctoral candidate advised by Dr. Cristina Rosa.

Through this project Natali proposes to analyze plasmodesmata (PD), the highly complex and still not completely characterized channels for intercellular movement of solutes, metabolites, and macromolecules in plants, by using virus-encoded movement proteins (MPs) as molecular probes.

These viral non-structural proteins exploit PD to facilitate virus cell-to-cell movement by two mechanisms: in the first, viral MPs dilate PD to transport viral nucleoprotein complexes to adjacent cells; in the second, MPs assemble into tubules inside the PD, displacing the desmotubule, compressed endoplasmic reticulum (ER) that transverses the cell junctions, to transport fully assembled virions.

Recent results in the Rosa Lab show that the ER is still present inside PD during plant infection by Ourmia melon virus (OuMV), a tubule-forming virus, supporting previous studies that hypothesized a mixed model of local transport for this virus, via RNA as well as via virions.

Özber's overarching goal is to examine the mechanism of OuMV movement and decipher the structural changes in PD during OuMV infection by a combination of super-resolution microscopy (a new capability available at Penn State) and confocal microscopy.

The specific aim of this project is to:

  • Investigate if the presence of the desmotubule in PD is dependent on the shape of PD and the developmental stage of the leaf;
  • Reveal the virus-induced structural changes in PD.

Results from this proposal will help to extend knowledge of the different movement strategies of plant viruses and give new insights into structural changes of PD during viral infection and plant development.

The College of Agricultural Sciences Graduate Student Competitive Grants Program is sponsored by the College of Agricultural Sciences Office for Research and Graduate Education. This program is a unique opportunity available to graduate students advised by College of Agricultural Sciences (CAS) faculty. The program serves as professional development for all CAS graduate students by providing funds to support master or doctoral research.