New Publication – Buhrow et al 2016

Buhrow, L.M., Clark, S.M., Loewen, M.C. (2016) Identification of an attenuated barley stripe mosaic virus for the virus-induced gene silencing of pathogenesis-related wheat genes. Plant Methods 12:12. doi: 10.1186/s13007-016-0112-z.

This work represents, in part, our foray into the use of Virus Induced Genes Silencing (VIGS), for knocking down the expression of wheat genes, and testing the effect of these knockdowns on the plants resistance to wheat fungal diseases, such as Fusarium head blight (FHB).  In this instance we identified a novel variant of the VIGS expression system that imposes less ‘viral’ stress on the plant system, to enable more meaningful phenotyping of the FHB disease over the course of the experiment.

Open Grad Student Position

Graduate Student Position Available

Queen’s University / National Research Council – Ottawa

Supervisors: Dr. Michele Loewen & Dr. John Allingham

Start Date: May 2016 or sooner if possible.

Please visit our Jobs page for more information: Loewen Lab Jobs

Interested individuals should contact Dr. Michele Loewen as soon as possible at: michele.loewen@queensu.ca

Welcome Mr. James Wells and Dr. Zerihun Demissie

The lab is pleased to welcome two new members including, Mr James Wells and Dr. Zerihun Demissie.  James is co-op student joining us from the Queen’s University Biochemistry Coo-op Program.  He is undertaking an 8 month term with us working on enzymes involved in carotenoid metabolism in wheat kernels.  Ze joins us having recently completed his PhD in Plant Molecular Biology and Biochemistry at UBC-Okanagan with Dr. Solheil Mahmoud, and a short post-doctoral stint at Brock University with Dr. Vince DeLuca.  Ze will be working on projects focused on hormone signalling  and ABC transporter targets as they relate to the development of resistance to the wheat fungal pathogen, Fusarium Head Blight.

james ze

Four New Publications: 2014 & 2015

Please visit our Publications Page for details:

Choudhary, P., & Loewen, M.C., (2015) Cell Biol. Int. Aug 27. doi: 10.1002/cbin.10541. [Epub ahead of print].

Choudhary, P., & Loewen, M.C. (2015)  J Biochem. 2015 Jul 30. pii: mvv072. [Epub ahead of print].

Galka MM, Rajagopalan N, Buhrow LM, Nelson KM, Switala J, Cutler AJ, Palmer DR, Loewen PC, Abrams SR, Loewen MC. (2015) PLoS One. 2015 Jul 21;10(7):e0133033. doi: 10.1371/journal.pone.0133033.

Pydi, S.P., Sobotkiewca, T., Bilakanti, R., Bhullar, R.P., Loewen, M.C., Chelikani, P., (2014)  J. Biol. Chem. 289:25054-25066.

New Publication – Dorosh et al., 2014

Lyudmyla Dorosh, Nandahkishore Rajagopalan, Michele C. Loewen, Maria Stepanova (2014)  Molecular mechanisms in the selective basal activation of pyrabactin receptor 1: comparative analysis of mutants . Febs Open Bio 2014 DOI: 10.1016/j.fob.2014.05.001 .

This work represents a comparative computational analysis of the dynamics of the interactions between abscisic acid receptors and their downstream signalling target, Type2 protein phosphatases.  In particular the effect of sets of mutations on the basal or constitutive activity of the receptors is considered.

New Publication – Benson et al., 2014

Benson, C.L., Kepka, M., Wunschel., C., Rajagopalan, N., Nelson, K.M., Christmann, A., Abrams, S.R., Griill, E., Loewen, M.C. (2014) Abscisic acid analogs as chemical probes for dissection of abscisic acid responses in Arabidopsis thaliana.  Phytochemistry. EPub ahead of Print, April 2014.

This work reposents a caollabortive effort between the labs of Dr. Grill in Germany and Dr. Abrams and Loewen in Canada.  In this work we have carried out a structure activity study of a selection of analogs of abscisic acid, looking at both in vitro characteristics by enzymatic assay and isothermal titration calorimietry, and physiological effect on germination, root growth and stomatal aperture.  Together the results highlight the selectivity and specificity of select analogs in physiological functions and for differentiating the functionalities of the broader family of abscisic acid receptors.

New Publication – Kharenko et al., 2013

Olesya A. Kharenko; Devin Polichuk; Ken M. Nelson; Suzanne R. Abrams; Michele C. Loewen (2013) Identification and characterization of interactions between abscisic acid and human heat shock protein 70 family members J Biochem 154:383-391 [PDF]

This work represents a twist in our chemical proteomics strategy, having here applied it not to plant target tissues, but to human cell extracts.  ABA is well known to have positive beneficial effects on human health, but the primary targets of ABA in mediating its effects remain enigmatic.  Here we present evidence of an interaction between ABA and a heatshock protein, glucose responsive protein 78,  involved in a variety of human conditions including diabetes and immunological responses and cancer.

Welcome Ms. Yuping Lu!

Yuping Lu comes to us part time from the lab of Dr. John Balsevich here at NRC.  Yuping is an expert plant natural products chemist.  She is joining our group to carry out wheat metabolite fractionation and enrichment.  She will be working with Dr. Kishore Rajagopalan and Ms. Khanh Luu on elucidation of functional aspects of fungal disease resistance and susceptibilty in wheat.

Yuping

NEW PUBLICATION – KHARENKO ET AL., 2013

Olesya A. Kharenko, Pooja Choudhary, Michele C. Loewen (2013) Abscisic acid binds to recombinant Arabidopsis thaliana G-protein coupled receptor-type G-protein 1 in Sacaromycese cerevisiae and in vitro. Plant Physiol Biochem 68:32-6.

This work demonstrates that the phytohormone abscisic acid binds to a recombinant form of the GTG1 protein, both in intact yeast cell membranes and to affinity enriched GTG1 protein, insupport of the GTG1 protein being an abscisic acid binding protein.