Dr Jo Hepworth
Jo is plant geneticist with a passion for understanding how plants coordinate their growth with their environment.
She is currently working with Dr Judith Irwin and Prof Steve Penfield, adapting her previous work with Prof Dame Caroline Dean on the mechanism and evolution of temperature integration in the model plant Arabidopsis thaliana, to the much bigger and genetically more complex Brassica napus (oilseed rape), as part of the BRAVO project.
Jo is investigating how vernalisation (the process in which plants register winter, so that they flower in spring) affects flowering time and branching in rapeseed.
She started working on vernalisation in Caroline Dean's group, which works on the genetic mechanisms underlying flowering time control, particularly at the key floral repressor FLOWERING LOCUS C (FLC).
FLC is a major regulator of development in Arabidopsis thaliana, as its expression determines the life history of the plant by controlling the timing of the transition to flowering. FLC expression must be repressed by experiencing winter before flowering can occur, in a process called vernalisation. However, although vernalisation allows plants to synchronise flowering with the end of winter, how do plants identify “winter”? In the field during autumn and winter temperatures can span twenty degrees daily, more than the difference between autumn and winter and aims to understand how plants tell the difference.
By working closely with Dr Rea Antoniou Kourounioti in Prof. Martin Howard’s group, the group have exploited the FLC system to determine how organisms can measure and integrate temperature information over months to accurately recognise the passing seasons in time to complete their life cycle.
The group have combined field and controlled-environment experiments on mutants and natural variants of Arabidopsis thaliana to investigate the contribution of known pathways to temperature sensing, and how these pathways have been locally adapted, and used these to develop mathematical models to both inform us of the underlying mechanism of temperature sensing, and predict gene responses to different winters.
- Read the news story about the Dean lab's work on drivers of vernalisation
- Read the paper; Absence of warmth permits epigenetic memory of winter in Arabidopsis - Jo Hepworth, Rea L. Antoniou-Kourounioti, Rebecca H. Bloomer, Catja Selga, Kristina Berggren, Deborah Cox, Barley R. Collier Harris, Judith A. Irwin, Svante Holm, Torbjörn Säll, Martin Howard & Caroline Dean
Nature communications 9 p639
Publisher’s version: 10.1038/s41467-018-03065-7
Flowering Locus C's Lessons: Conserved Chromatin Switches Underpinning Developmental Timing and Adaptation.
Plant Physiology 168 p1237-45
Publisher’s version: 10.1104/pp.15.00496