QUEEN'S BIOLOGY MCIB SEMINAR SERIES
  • Home
  • Schedule
  • Contact

Seminar series of the Molecular, Cellular & Integrative Biology
research groups at Queen's University

Tues Sept 3rd //  Investigating Suberin Biosynthesis in Poplar: Candidate Genes and Chemical Composition

8/28/2019

 
Picture
Meghan Rains, PhD student
Algoma University / Queen's University

Pathogens, climate change, and pollution represent important stressors that plants face continuously. To better prepare for a changing terrestrial landscape, we must understand how plants adapt and cope with various environmental stressors. The plant cuticle and suberized cells (cork) are among the critical adaptations that plants developed when they moved from an aqueous environment to land. These cell wall-specific extracellular lipid barriers provide the first line of defense against pathogens and control water exchange. The cuticle covers most aerial plant surfaces and is composed of a polymer of fatty acids and waxes. The periderms of roots, tubers, and tree bark, contain waxes and suberin –an esterified network of glycerol and fatty acid derivatives that is bound to a lignin-like polymer. Although structural models have been inferred from chemical depolymerizations, the insoluble nature of these polymers makes analyses challenging, and consequently, the native structure of suberin remains unclear. Much of the current research on suberin biosynthesis has focused on the model plant Arabidopsis thaliana. However, the complete pathways have not yet been fully characterized, and it is unclear how knowledge derived from Arabidopsis translates to woody tree periderms. This dissertation work used a combination of chemical and molecular approaches to identify candidate genes for suberin biosynthesis and to investigate the structure of the polyester using the model tree, Populus trichocarpa (Poplar). The results from this research further our understanding of suberin structure in tree bark, establish improved methodologies, and generate hypotheses for future targeted studies.

Wednesday Aug 21 // Calmodulin-like proteins in plant counterdefense against viral RNA silencing suppressors

8/14/2019

 
Picture
Dr. Kenji Nakahara, Lecturer
Pathogen-Plant Interactions Group, Research Faculty of Agriculture,
Hokkaido University, Sapporo, Hokkaido 060-8589, Japan

RNA silencing is one of major antiviral systems in plants and most plant viruses encode RNA silencing suppressors (RSS) to facilitate their infection of plants by inhibiting the plant’s endogenous antiviral RNA-silencing machinery. Previously, a tobacco calmodulin-like protein (CML), termed rgs-CaM, has been reported to interact with HC-Pro and 2b, which are RSSs encoded by members of the genus Potyvirus and Cucumovirus, respectively. We have shown that the tobacco CML counteractively functions as an antiviral defense factor to direct degradation of its interacting RSS proteins via autophagy. Further studies suggest that the rgs-CaM-mediated counterdefense against RSSs involves salicylic acid signaling. Plants encode dozens of CMLs (50 and 32 CMLs in Arabidopsis and rice, respectively). Several CMLs of tobacco and other plants are similar to rgs-CaM in their amino acid sequences, suggesting possible binding to viral RSSs and involvement with antiviral defense. We have been investigating whether Arabidopsis CML orthologs of rgs-CaM may be involved in plant/virus interaction and I will present data from research in Japan and recent collaborative work in the Snedden lab here at Queen’s.

    Archives

    February 2021
    January 2021
    December 2020
    November 2020
    October 2020
    September 2020
    August 2020
    June 2020
    April 2020
    March 2020
    February 2020
    January 2020
    November 2019
    October 2019
    September 2019
    August 2019
    July 2019
    May 2019
    April 2019
    March 2019
    February 2019
    January 2019
    November 2018
    October 2018
    September 2018
    June 2018
    May 2018
    April 2018
    March 2018
    February 2018
    January 2018
    November 2017
    October 2017
    September 2017
    June 2017
    May 2017
    April 2017
    March 2017
    February 2017
    January 2017
    December 2016
    November 2016
    October 2016
    September 2016
    August 2016

Powered by Create your own unique website with customizable templates.
  • Home
  • Schedule
  • Contact