Tuesday, March 3, 2009

Miranda Meents

keywords: Arabidopsis, secondary cell walls, xylan, xylem, cisternal maturation, glycosyltransferases

Originally from Calgary, AB, I got my BSc in Biological Sciences from the University of Lethbridge in 2009. I did my Undergraduate Honours Thesis with Dr. Elizabeth Schultz, helping to characterize an Arabidopsis mutant with a novel MONOPTEROS allele. I used microscopy (e.g. light, fluorescence, SEM) to look at embryo and ovule development, anther dehiscence, pollen tube growth, and floral anatomy.

After graduating in 2009 I took a job as a research technician working at the University of Alberta on the TRIA project, a large collaborative project investigating the Mountain Pine Beetle system. I spent part of my time the first year in the lab of Dr. Felix Sperling, where I took over a project developing a sequencing-based SNP genotyping method to distinguish different species of fungal symbionts associated with the beetle. The rest of the time I was in the lab of Dr. Janice Cooke, where we worked to elucidate the impact of tree water status and host species on tree defence against mountain pine beetle attack, combining bioinformatic, physiological, and molecular methods.

Then, in 2012, I joined the Samuels lab as a Master’s student, before transferring to a PhD in 2014. While the hemicellulose xylan is a major component of plant secondary cell walls, the enzymes involved in its synthesis have only recently been discovered, and xylan synthesis is not fully understood. I will use high resolution microscopy to look at synthesis in the Golgi of xylan by glycosyltransferases like IRX10. I will use an Arabidopsis line with an inducible ‘switch’ turning on the master transcription factor VND7. One of the things turned on with VND7 induction is secondary cell wall, and xylan, synthesis. By localizing both the biosynthetic enzyme(s)  and their products within the Golgi we hope to test the cisternal maturation model, which predicts a maturation of products within Golgi stacks as they move from cis to trans, while glycosyltransferases are recycled ‘backward’ to earlier stacks. This component of the cisternal maturation model has never been tested explicitly, and has implications for cell biology in all eukaryotes, across the kingdoms.

Publications

Meents MJ, Watanabe Y, Samuels AL (2018) The Cell Biology of Secondary Cell Wall Biosynthesis. Annals of Botany. published online [view abstract]

de Michele, R, McFarlane, HE, Parsons, HT, Meents, MJ, Lao, J, González Fernández-Niño, SM, Petzold, CJ, Frommer, WB, Samuels, AL, Heazlewood, JL (2016) Free-flow electrophoresis of plasma membrane vesicles enriched by two-phase partitioning enhances the quality of the proteome from Arabidopsis seedlings. Journal of Proteome Research. 15(3):900-913. [view abstract]

Watanabe Y, Meents MJ, McDonnell LM, Barkwill S, Sampathkumar A, Cartwright HN, Demura T, Ehrhardt DW, Samuels AL, Mansfield SD (2015) Visualization of cellulose synthases in Arabidopsis secondary cell walls. Science 350:198-203. [view abstract]

Arango-Velez A, Galindo Gonzalez LM, Meents MJ, El Kayal W, Cooke BJ, Linsky J, Lusebrink I, Cooke JEK (2013) Influence of water deficit on the molecular responses of Pinus contorta x Pinus banksiana mature tree to infection by the mountain pine beetle fungal associate, Grosmannia clavigera. Tree Physiology. [view abstract]

Garrett JJ, Meents MJ, Blackshaw MT, Blackshaw LC, Hou H, Styranko D, Kohalmi S, Schultz EA (2012) A novel, semi-dominant allele of MONOPTEROS provides insight into leaf initiation and vein pattern formation. Planta. 236(1):297-312. [view abstract]