Imperial College London Featured PhD Programmes
Heriot-Watt University Featured PhD Programmes
University College London Featured PhD Programmes
University of West London Featured PhD Programmes
University College London Featured PhD Programmes

Identifying the evolutionary origins of the MADS-box floral quartet mechanism in seedless vascular plants


Project Description

Despite its commonplace occurrence in today’s environment, the reproduction of plants via flowers and seeds is a recent evolutionary innovation arising from an ancestral seedless reproductive system similar to that still found in a subset of today’s plants (e.g. ferns, horsetails, clubmosses). How the genetic pathways that regulate seed and flower development first evolved represents a black hole in our understanding of plant evolution, and has the potential to unlock significant advances in our understanding of plant reproduction.

The characteristic structure of flowers, with concentric rings of different organ types, arises through a mechanism of co-operative protein binding between floral homeotic genes (e.g. APETALA1, PISTILLATA, AGAMOUS), which are members of the MADS-box gene superfamily of transcription factors. The ‘ABC’ or ‘floral quartet’ model(1) explains organ identity specification by these related proteins binding to form a tetramer (or quartet) with the precise combination of proteins involved activating different populations of downstream gene targets to achieve different organ identities. The evolutionary origin of this fundamental mechanism remains unknown. MADS-box genes closely related to the floral homeotic genes are found in the non-flowering sister-group to angiosperms, the gymnosperms, where it is hypothesised that a simplified version of the floral quartet regulates reproductive organ identity. Whilst MADS-box genes have been found in the closest seedless relatives to seed-bearing plants (the ferns), they do not belong to the same phylogenetic clade as the floral homeotic genes, and their functions are unknown.

This project aims to test whether the ancestral floral quartet mechanism in seed plants arose from a pre-existing similar mechanism in a seedless ancestor. The project will compare the functions and binding properties of MADS-box genes from the newly-established and genetically-tractable fern model system, Ceratopteris richardii(2,3). This will be achieved through a mix of in vivo and in vitro approaches, comparing Ceratopteris and the established angiosperm model for floral development, Arabidopsis thaliana, and investigating the functions of MADS-box genes in Ceratopteris as a proxy for their ancestral roles in plant development. Experiments will include the creation and analysis of transgenic plants in both species, combined with biochemical and bioinformatic assays to identify the protein binding partners and downstream targets of candidate genes.

Start date: October 2020.

Interested in applying? Please contact Andy Plackett () for further details.

Funding Notes

Funding for this studentship is available for three years from the University of Birmingham College of Life Sciences

References

1. Theissen et al. (2016). MADS-domain transcription factors and the floral quartet model of flower development: linking plant development and evolution. Development 143: 3259. doi: 10.1242/dev.134080
2. Plackett et al. (2014). High-efficiency stable transformation of the model fern species Ceratopteris richardii via microparticle bombardment. Plant Physiology 165: 3. doi: 10.1104/pp.113.231357
3. Plackett, Conway et al. (2018). LEAFY maintains apical stem cell activity during shoot development in the fern Ceratopteris richardii. eLIFE doi: 10.7554/eLife.39625

How good is research at University of Birmingham in Biological Sciences?

FTE Category A staff submitted: 42.80

Research output data provided by the Research Excellence Framework (REF)

Click here to see the results for all UK universities

Email Now

Insert previous message below for editing? 
You haven’t included a message. Providing a specific message means universities will take your enquiry more seriously and helps them provide the information you need.
Why not add a message here
* required field
Send a copy to me for my own records.

Your enquiry has been emailed successfully





FindAPhD. Copyright 2005-2020
All rights reserved.