Professor Peter McCourt

Peter McCourt



St. George (downtown)

CSB Appointment


Research Areas

Bioinformatics / Computational Biology, Chemical Biology, Developmental Biology, Genetics / Genomics, Molecular Biology, Plant Biology, Systems Biology


Ph.D. Michigan State University 1986
M.Sc. Genetics University of Alberta 1983
B.Sc. Genetics University of Alberta 1978

Titles and Honors

Canada Research Chair in Plant Molecular Biology
Jack Dainty Distinguished Professor

Primary Undergraduate Department

Cell & Systems Biology

Graduate Programs

Cell & Systems Biology

Research Description

The general objectives of our research group are the development of genetic, genomic and chemical biology screening technologies to identify genes that control the synthesis and signaling of select plant hormones. Presently, we are focused on two hormones, abscisic acid (ABA) and strigolactones (SLs). ABA is involved in protecting plants from abiotic stresses such as drought and cold. We are developing meso-scale genetic and protein-protein interaction maps between a few hundred genes involved in the ABA response in Arabidopsis. With an understanding of these ABA networks, it will be possible to make rational improvements in crop species. Towards this end, we are presently translating information garnered from Arabidopsis to crops such as canola and soybean. Although SLs, also have many hormonal roles in Arabidopsis, these compounds are mostly known for their ability to act as germination cues in host/parasite plant interactions. These parasites have evolved strong seed dormancy, which is broken only when they sense SLs extruding from a host’s root. The use of SLs as a germination cue, which allows the parasite to coordinate its lifecycle with its host, has devastating consequences for developing world agriculture. In sub-Saharan Africa alone, parasitic plants have infested up to two-thirds of the arable land and represent one of the largest challenges to food security on that continent, affecting over 100 million people. To directly combat this major problem, we are developing high throughput chemical genomics screens to identify SL mimics that fool parasitic plants into germinating in the absence of a host.

Contact Information

Office Phone: 416-978-0523
Office: ESC4059
Lab: ESC4055
Lab Phone: 416-978-0837

Mailing Address

Department of Cell & Systems Biology
University of Toronto
25 Willcocks St.
Toronto, ON M5S 3B2

Visit lab’s website

Recent News

Excellence and excitement at CSB Research Day 2024

The wide variety of cutting-edge science in the Department of Cell & Systems Biology was on full display in the distinguished halls of Hart House…

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End of the tunnel for crop loss due to parasitic plants

Parasitic plants devastate entire fields of crops every year, resulting in billions of dollars of food lost. As food prices rise, protecting crops…

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Hybrid receptor from Lumba lab suggests how parasitic plants evolve

Professor Shelley Lumba’s lab found out how benign plants develop the ability to become parasites on other plants in new research published in PNAS.…

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Structural analysis of a hormone-bound Striga strigolactone receptor

Arellano-Saab A, Skarina T, Xu Z, McErlean CSP, Savchenko A, Lumba S, Stogios PJ, McCourt P
2023, Nature Plants,

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50 years of Arabidopsis research: highlights and future directions

Provart NJ, Alonso J, Assmann SM, Bergmann D, Brady SM, Brkljacic J, Browse J, Chapple C, Colot V, Cutler S, Dangl J, Ehrhardt D, Friesner JD, Frommer WB, Grotewold E, Meyerowitz E, Nemhauser J, Nordborg M, Pikaard C, Shanklin J, Somerville C, Stitt M, Torii KU, Waese J, Wagner D, McCourt P
2015, The New phytologist, 26465351

Structure-function analysis identifies highly sensitive strigolactone receptors in Striga

Toh S, Holbrook-Smith D, Stogios PJ, Onopriyenko O, Lumba S, Tsuchiya Y, Savchenko A, McCourt P
2015, Science (New York, N.Y.), 350, 203-7, 26450211

PARASITIC PLANTS. Probing strigolactone receptors in Striga hermonthica with fluorescence

Tsuchiya Y, Yoshimura M, Sato Y, Kuwata K, Toh S, Holbrook-Smith D, Zhang H, McCourt P, Itami K, Kinoshita T, Hagihara S
2015, Science (New York, N.Y.), 349, 864-8, 26293962

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Detection of Parasitic Plant Suicide Germination Compounds Using a High-Throughput Arabidopsis HTL/KAI2 Strigolactone Perception System

Toh S, Holbrook-Smith D, Stokes ME, Tsuchiya Y, McCourt P
2014, Chemistry & biology, 21, 988-98, 25126711

Towards personalized agriculture: what chemical genomics can bring to plant biotechnology

Stokes ME, McCourt P
2014, Frontiers in plant science, 5, 344, 25183965

A mesoscale abscisic acid hormone interactome reveals a dynamic signaling landscape in Arabidopsis

Lumba S, Toh S, Handfield LF, Swan M, Liu R, Youn JY, Cutler SR, Subramaniam R, Provart N, Moses A, Desveaux D, McCourt P
2014, Developmental cell, 29, 360-72, 24823379

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ABI3 controls embryo degreening through Mendel’s I locus

Delmas F, Sankaranarayanan S, Deb S, Widdup E, Bournonville C, Bollier N, Northey JG, McCourt P, Samuel MA
2013, Proceedings of the National Academy of Sciences of the United States of America, 110, E3888-94, 24043799

Characterization of a cruciferin deficient mutant of Arabidopsis and its utility for overexpression of foreign proteins in plants

Lin Y, Pajak A, Marsolais F, McCourt P, Riggs CD
2013, PloS one, 8, e64980, 23724110

Forward genetic screening for the improved production of fermentable sugars from plant biomass

Stamatiou G, Vidaurre DP, Shim I, Tang X, Moeder W, Bonetta D, McCourt P
2013, PloS one, 8, e55616, 23383246

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HY5 is involved in strigolactone-dependent seed germination in Arabidopsis

Toh S, McCourt P, Tsuchiya Y
2012, Plant signaling & behavior, 7, 556-8, 22516816

The embryonic leaf identity gene FUSCA3 regulates vegetative phase transitions by negatively modulating ethylene-regulated gene expression in Arabidopsis

Lumba S, Tsuchiya Y, Delmas F, Hezky J, Provart NJ, Shi Lu Q, McCourt P, Gazzarrini S
2012, BMC biology, 10, 8, 22348746

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Thermoinhibition uncovers a role for strigolactones in Arabidopsis seed germination

Toh S, Kamiya Y, Kawakami N, Nambara E, McCourt P, Tsuchiya Y
2012, Plant & cell physiology, 53, 107-17, 22173099

Strigolactones as small molecule communicators

Tsuchiya Y, McCourt P
2012, Molecular bioSystems, 8, 464-9, 22027812

Next-generation mapping of Arabidopsis genes

Austin RS, Vidaurre D, Stamatiou G, Breit R, Provart NJ, Bonetta D, Zhang J, Fung P, Gong Y, Wang PW, McCourt P, Guttman DS
2011, The Plant journal : for cell and molecular biology, 67, 715-25, 21518053

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A small-molecule screen identifies new functions for the plant hormone strigolactone

Tsuchiya Y, Vidaurre D, Toh S, Hanada A, Nambara E, Kamiya Y, Yamaguchi S, McCourt P
2010, Nature chemical biology, 6, 741-9, 20818397

Arabidopsis: a rich harvest 10 years after completion of the genome sequence

McCourt P, Benning C
2010, The Plant journal : for cell and molecular biology, 61, 905-8, 20409265

Plant nuclear hormone receptors: a role for small molecules in protein-protein interactions

Lumba S, Cutler S, McCourt P
2010, Annual review of cell and developmental biology, 26, 445-69, 20590451

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Plant chemical genetics

McCourt P, Desveaux D
2010, The New phytologist, 185, 15-26, 19825020

Strigolactones: a new hormone with a past

Tsuchiya Y, McCourt P
2009, Current opinion in plant biology, 12, 556-61, 19726222

Abscisic acid inhibits type 2C protein phosphatases via the PYR/PYL family of START proteins

Park SY, Fung P, Nishimura N, Jensen DR, Fujii H, Zhao Y, Lumba S, Santiago J, Rodrigues A, Chow TF, Alfred SE, Bonetta D, Finkelstein R, Provart NJ, Desveaux D, Rodriguez PL, McCourt P, Zhu JK, Schroeder JI, Volkman BF, Cutler SR
2009, Science (New York, N.Y.), 324, 1068-71, 19407142

Using reverse genetics to develop small knockout collections for specific biological questions

Northey J, McCourt P
2009, Methods in molecular biology (Clifton, N.J.), 495, 1-10, 19085154

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CHOTTO1, a double AP2 domain protein of Arabidopsis thaliana, regulates germination and seedling growth under excess supply of glucose and nitrate

Yamagishi K, Tatematsu K, Yano R, Preston J, Kitamura S, Takahashi H, McCourt P, Kamiya Y, Nambara E
2009, Plant & cell physiology, 50, 330-40, 19109301

The ABA receptors — we report you decide

McCourt P, Creelman R
2008, Current opinion in plant biology, 11, 474-8, 18774332

A novel role for protein farnesylation in plant innate immunity

Goritschnig S, Weihmann T, Zhang Y, Fobert P, McCourt P, Li X
2008, Plant physiology, 148, 348-57, 18599656

The synthesis of the rhamnogalacturonan II component 3-deoxy-D-manno-2-octulosonic acid (Kdo) is required for pollen tube growth and elongation

Delmas F, Séveno M, Northey JG, Hernould M, Lerouge P, McCourt P, Chevalier C
2008, Journal of experimental botany, 59, 2639-47, 18503041

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Plant hormone receptors: perception is everything

Chow B, McCourt P
2006, Genes & development, 20, 1998-2008, 16882977

A small-molecule screen in C. elegans yields a new calcium channel antagonist

Kwok TC, Ricker N, Fraser R, Chan AW, Burns A, Stanley EF, McCourt P, Cutler SR, Roy PJ
2006, Nature, 441, 91-5, 16672971

High-throughput screening of small molecules for bioactivity and target identification in Caenorhabditis elegans

Burns AR, Kwok TC, Howard A, Houston E, Johanson K, Chan A, Cutler SR, McCourt P, Roy PJ
2006, Nature protocols, 1, 1906-14, 17487175

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Preventing leaf identity theft with hormones

Lumba S, McCourt P
2005, Current opinion in plant biology, 8, 501-5, 16054431

Plant biology: a receptor for gibberellin

Bonetta D, McCourt P
2005, Nature, 437, 627-8, 16193028

Molecular tailoring of farnesylation for plant drought tolerance and yield protection

Wang Y, Ying J, Kuzma M, Chalifoux M, Sample A, McArthur C, Uchacz T, Sarvas C, Wan J, Dennis DT, McCourt P, Huang Y
2005, The Plant journal : for cell and molecular biology, 43, 413-24, 16045476

Dude, where’s my phenotype? Dealing with redundancy in signaling networks

Cutler S, McCourt P
2005, Plant physiology, 138, 558-9, 15955914

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Systems approaches to understanding cell signaling and gene regulation

Provart NJ, McCourt P
2004, Current opinion in plant biology, 7, 605-9, 15337105

The transcription factor FUSCA3 controls developmental timing in Arabidopsis through the hormones gibberellin and abscisic acid

Gazzarrini S, Tsuchiya Y, Lumba S, Okamoto M, McCourt P
2004, Developmental cell, 7, 373-85, 15363412

The FUS3 transcription factor functions through the epidermal regulator TTG1 during embryogenesis in Arabidopsis

Tsuchiya Y, Nambara E, Naito S, McCourt P
2004, The Plant journal : for cell and molecular biology, 37, 73-81, 14675433

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Hormone signalling from a developmental context

Chow B, McCourt P
2004, Journal of experimental botany, 55, 247-51, 14673027

Lack of recognition of Nepsilon-(carboxymethyl)lysine by the mouse liver reticulo-endothelial system: implications for pathophysiology

Svistounov DN, Berg TJ, McCourt PA, Zykova SN, Elvevold KH, Nagai R, Horiuchi S, Smedsrod BH
2003, Biochemical and biophysical research communications, 309, 786-91, 13679041

Cross-talk in plant hormone signalling: what Arabidopsis mutants are telling us

Gazzarrini S, McCourt P
2003, Annals of botany, 91, 605-12, 12714359

The ABSCISIC ACID INSENSITIVE 3 (ABI3) gene is modulated by farnesylation and is involved in auxin signaling and lateral root development in Arabidopsis

Brady SM, Sarkar SF, Bonetta D, McCourt P
2003, The Plant journal : for cell and molecular biology, 34, 67-75, 12662310

Hormone evolution: The key to signalling

Kushiro T, Nambara E, McCourt P
2003, Nature, 422, 122, 12634761

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A screen for genes that function in abscisic acid signaling in Arabidopsis thaliana

Nambara E, Suzuki M, Abrams S, McCarty DR, Kamiya Y, McCourt P
2002, Genetics, 161, 1247-55, 12136027

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McCourt P
1999, Annual review of plant physiology and plant molecular biology, 50, 219-243, 15012209

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