Photo of Shelley Hepworth

Shelley Hepworth


Degrees:B.Sc. (Waterloo), Ph.D. (Toronto)
Phone:613-520-2600 x 4214
Office:Office: 315 Nesbitt Building
Lab: 311 Nesbitt Building
Website:Visit my lab website


The Hepworth Lab is a nationally and internationally integrated research unit at Carleton University. Agriculture is a major sector of the Canadian economy. Population growth coupled with the impacts of climate change has created the demand for a second “green revolution” to improve and stabilize crop productivity. Plant architecture is a major determinant of crop yield. The long-term objective of our research is to understand how genes control plant architecture traits related to crop yield.

Plant shape and form relies on the activity of self-maintaining groups of stem cells called meristems. Meristems provide a continuous supply of daughter cells for incorporation into new leaves, flowers, and shoots throughout the life cycle. Our work focuses on the role of organ boundaries located on the meristem periphery. Boundaries are domains of low growth that separate the meristem from new organs as they emerge. These domains preserve growth by forming a barrier that allows stem cells to continue propagating in the center of the meristem and organs to continue developing at the periphery. Boundaries are also the source of axillary meristems that give rise to branches and flowers on the inflorescence and the site of abscission zones that control the detachment and dispersal of fruits, leaves, flowers, and seeds. Despite the importance of boundaries in controlling plant architecture, little is known about genetic networks that control their function during the reproductive phase. Our work is at the forefront of such discoveries.

We work with university and government researchers in Canada (e.g. University of Ottawa, National Research Council Canada, Agriculture and Agri-Food Canada) and other parts of the world (e.g. Institut Jean-Pierre Bourgin in France, Lanzhou University in China) sharing students, ideas, and resources to improve the speed and efficiency of crop development.

The Hepworth lab is always seeking new students. If you want to learn more about our research, we look forward to hearing from you. Contact the Hepworth lab at For details about specific projects, please visit our website

Selected Publications

Y. Wang, B.C. Salasini, M. Khan, B. Devi, M. Bush, R. Subramaniam, and S.R. Hepworth. (2019) Clade I TGA bZIP transcription factors mediate BLADE-ON-PETIOLE dependent regulation of development. Plant Physiology (in press)

J.L. Parsons, S.L. Martin, T. James, G. Golenia, E.A. Boudko, and S.R. Hepworth. (2019) Polyploidization for the genetic improvement of Cannabis sativa. Frontiers in Plant Science (in press)

N. Woerlen, G. Allam, A. Popescu, L. Corrigan, V. Pautot, and S.R. Hepworth. (2017) Repression of BLADE-ON-PETIOLE genes by KNOX homeodomain protein BREVIPEDICELLUS is essential for differentiation of secondary xylem in Arabidopsis roots. Planta 245:1079-1090.

S.R. Hepworth, and V. Pautot. (2015) Beyond the divide: boundaries for patterning and stem cell regulation in plants. Frontiers in Plant Science 6, 1052.

Khan, L. Ragni, P. Tabb, B.C. Salasini, S. Chatfield, R. Datla, J. Lock, X. Kuai, C. Despres, M. Proveniers, H. Morin, J.P. Rulliere, S. Citerne, S.R. Hepworth, and V. Pautot. (2015) Repression of lateral organ boundary genes by PENNYWISE and POUND-FOOLISH is essential for meristem maintenance and flowering in Arabidopsis thaliana. Plant Physiology 169, 2166-2186.

M. Khan, H. Xu, and S.R. Hepworth. (2014) BLADE-ON-PETIOLE genes: setting boundaries in development and defense. Plant Science 215-216, 157-171.

M. Khan, M. Xu, J. Murmu, P. Tabb, Y. Liu, K. Storey, S.M. McKim, C.J. Douglas, and S.R. Hepworth (2012). Antagonistic interaction of BLADE-ON-PETIOLE1 and 2 with BREVIPEDICELLUS and PENNYWISE regulates Arabidopsis inflorescence architecture. Plant Physiology 158,946-960.

J. Murmu, M.J. Bush, C. DeLong, S. Li, M. Xu, M. Khan, C. Malcolmson, P.R. Fobert, S. Zachgo, S.R. Hepworth. (2010) Arabidopsis bZIP transcription factors TGA9 and TGA10 interact with floral glutaredoxins ROXY1 and ROXY2 and are redundantly required for anther development. Plant Physiology 154, 1492-1504

M. Xu, T. Hu, S. McKim, G.W. Haughn and S. R. Hepworth. (2010) Arabidopsis BLADE-ON-PETIOLE1 and 2 promote floral meristem fate and determinacy in a previously undefined pathway targeting APETALA1 and AGAMOUS-LIKE24. Plant Journal 63, 974-989.

S.R. Hepworth, Y. Zhang, X. Li, S. McKim, and G.W. Haughn. (2005) BLADE-ON-PETIOLE-dependent signaling controls leaf and floral patterning in Arabidopsis. Plant Cell 17, 1-15.