Transformed: the plant whose sex life fascinated Charles Darwin

11 December 2018

Researchers have genetically transformed the Common Primrose (Primula vulgaris) for the first time in a development that could shed light on one of the plant world’s most renowned reproductive systems.

The complicated sex life of Primula was a subject that fascinated Charles Darwin and generations of geneticists that followed because it’s one of the best examples of heteromorphic flower development.

Heteromorphy (or heterostyly) is a phenomenon in which plants exhibit two or three distinct forms of flowers based on the position of the male and female sex organs. Now, some of the secrets that eluded Darwin could be revealed following the biotechnological success announced by researchers from the John Innes Centre, the University of East Anglia (UEA) and the Earlham Institute.

The technology known as Agrobacterium-mediated plant transformation involves using soil bacteria to insert or modify genes in a plant genome. Genetic transformation is a valuable tool that allows researchers to study gene function and genetically controlled characteristics in organisms.

It is a research method routinely used on model organisms such as Nicotiana benthamiana and Arabidopsis thaliana to understand the molecular workings of plants. However, these species cannot be used to study heteromorphy because their flowers are all homomorphic which means they are able to self-fertilise.

“Now we have a transformation system we can use gene editing tools such as CRISPR-Cas9 to work out exactly what the gene function is that controls heteromorphy in the Primula family,” said Sadiye Hayta, of the John Innes Centre.

“Longer term, there may be implications for commercial crops. If we understand the roles of these different genes we could take them over to a commercial crop and use it in a hybrid system,” she added.

Until now attempts to transform Primula have been unsuccessful because the plant has proved resistant to laboratory regeneration of whole plants from tissue culture.

The new transformation protocols reported in the peer-reviewed journal Plant Methods will allow the scientists of today to study the Primula at a molecular level.

The flowering plant is one of the best-known examples of heteromorphic flower development. This reproductive system enthralled not only Darwin but many leading geneticists from the early 1900s including William Bateson, the first director of the John Innes Centre and colleagues JBS Haldane, Cyril Darlington and Dorothea de Winton.

Darwin, in a landmark paper of 1862, worked out the functional significance of the different anatomical formations: they made the plants self-incompatible. This is Nature’s way of promoting cross-pollination to maintain genetic variation in the population, driving natural selection.

Fundamental research into heteromorphy has continued.  In a research paper in 2016 a UEA and John Innes Centre team, led by Prof Philip Gilmartin from UEA's School of Biological Sciences, identified the S-Locus supergene that controls heteromorphy as described by Darwin.

Armed with this fundamental knowledge and the newly announced transformation system, scientists can delve deeper into the mysteries of heteromorphy.

Prof Philip Gilmartin, whose laboratory started out on this scientific mission more than 20 years ago, said: “The development of a Primula transformation system is an important component of our lab’s long-term study to identify and characterise the genes that control development of the two forms of Primula flower studied by Charles Darwin.”

Co-author Mark Smedley, of the John Innes Centre said: “It is not every day you get to work on a paper that references Darwin. This is a fundamental story that scientists have been trying to unravel for 200 years.”

It’s a piece of research that would have excited Darwin. Towards the end of his illustrious career the author of On the Origin of Species remarked: “I do not think anything in my scientific life has given me so much satisfaction as making out the meaning of the structure of these plants.”

'Agrobacterium-mediated transformation systems of Primula vulgaris', appears in the peer reviewed journal Plant Methods. The research was funded by BBSRC and the Gatsby Foundation.

Notes to editors

For more information, please contact:

Hayley London

Marketing & Communications Officer, Earlham Institute (EI)

  • +44 (0)1603 450 107

hayley.london@earlham.ac.uk

The Earlham Institute (EI) is a world-leading research Institute focusing on the development of genomics and computational biology. EI is based within the Norwich Research Park and is one of eight institutes that receive strategic funding from Biotechnology and Biological Science Research Council (BBSRC) - £5.43m in 2017/18 - as well as support from other research funders. EI operates a National Capability to promote the application of genomics and bioinformatics to advance bioscience research and innovation.

EI offers a state of the art DNA sequencing facility, unique by its operation of multiple complementary technologies for data generation. The Institute is a UK hub for innovative bioinformatics through research, analysis and interpretation of multiple, complex data sets. It hosts one of the largest computing hardware facilities dedicated to life science research in Europe. It is also actively involved in developing novel platforms to provide access to computational tools and processing capacity for multiple academic and industrial users and promoting applications of computational Bioscience. Additionally, the Institute offers a training programme through courses and workshops, and an outreach programme targeting key stakeholders, and wider public audiences through dialogue and science communication activities.

www.earlham.ac.uk

Our mission is to generate knowledge of plants and microbes through innovative research, to train scientists for the future, to apply our knowledge of nature’s diversity to benefit agriculture, the environment, human health and wellbeing, and engage with policy makers and the public.

To achieve these goals we establish pioneering long-term research objectives in plant and microbial science, with a focus on genetics. These objectives include promoting the translation of research through partnerships to develop improved crops and to make new products from microbes and plants for human health and other applications. We also create new approaches, technologies and resources that enable research advances and help industry to make new products. The knowledge, resources and trained researchers we generate help global societies address important challenges including providing sufficient and affordable food, making new products for human health and industrial applications, and developing sustainable bio-based manufacturing.

This provides a fertile environment for training the next generation of plant and microbial scientists, many of whom go on to careers in industry and academia, around the world.


The John Innes Centre is strategically funded by the Biotechnology and Biological Sciences Research Council (BBSRC). In 2014-2015 the John Innes Centre received a total of £36.9 million from the BBSRC.

The Biotechnology and Biological Sciences Research Council (BBSRC) is part of UK Research and Innovation, a non-departmental public body funded by a grant-in-aid from the UK government.

BBSRC invests in world-class bioscience research and training on behalf of the UK public. Our aim is to further scientific knowledge, to promote economic growth, wealth and job creation and to improve quality of life in the UK and beyond.

Funded by government, BBSRC invested £469 million in world-class bioscience in 2016-17. We support research and training in universities and strategically funded institutes. BBSRC research and the people we fund are helping society to meet major challenges, including food security, green energy and healthier, longer lives. Our investments underpin important UK economic sectors, such as farming, food, industrial biotechnology and pharmaceuticals.