Self-incompatibility induced Programmed Cell Death in plants: Identification of new physiological and molecular mechanisms

PhD Supervisor: Dr Maurice Bosch ([Email Address Removed])
Co-Supervisors: Prof Moritz Nowack (Ghent University) & Prof Noni Franklin-Tong (University of Birmingham)

Self-incompatibility (SI) is a genetically controlled system to prevent self-fertilization in 60% of flowering plants, encouraging outbreeding and genetic diversity. Upon contact with the stigma, ‘self’ pollen is recognized as being incompatible, triggering a signalling network resulting in arrest of pollen tube growth, thus preventing fertilization. The SI system of Papaver, which triggers programmed cell death (PCD) in incompatible pollen tubes, is one of the best-studied SI systems and represents a model system for investigating intracellular signalling in plants, particularly in relation to PCD (1,2). We recently established that the Papaver SI-PCD system can be functionally transferred to Arabidopsis (3,4), providing an exciting and unique opportunity for a talented and motivated student to study SI-PCD using a combination of genetic and live-cell imaging approaches previously not feasible.

Using the tools now available with the Arabidopsis “SI” system, the successful candidate will identify and analyse key molecular mechanisms involved in regulating SI-PCD in Arabidopsis using the following multidisciplinary approach:

1. Actin dynamics and cytosolic acidification are key events that regulate SI-PCD (2). Using spatiotemporal live-cell imaging with genetically encoded markers, the student will perform ground-breaking studies to investigate how actin modifications and acidification are mechanistically involved in mediating SI-PCD in incompatible pollen.

2. A targeted proteomics approach has identified the functional involvement of endocytosis in the SI-PCD response. A pharmacological approach, using selected drugs that target endocytosis, in combination with fluorescent markers, will establish the importance of endocytosis for the SI-PCD response.

3. During a one year fully funded placement at the VIB research institute in Ghent, the student will identify key novel genes involved in SI-PCD by utilizing a powerful genetic screen following mutagenesis of Arabidopsis SI lines.

This cutting-edge collaborative project underpins possible solutions to food security. The PhD student will be registered at Aberystwyth University and based at IBERS, an internationally-recognised research and teaching institute providing a unique base for research in response to global challenges such as food security, bioenergy, sustainability and impacts of climate change. The successful candidate will be supervised by Maurice Bosch at IBERS, wo has a longstanding interest and track record in studying pollination and regulation of pollen tube growth. The project will be co-supervised by Noni Franklin-Tong, University of Birmingham, a world-leading scientist who established Papaver SI as a model system for investigating signalling and PCD in plants, and Moritz Nowack, Department of Plant Systems Biology, VIB Ghent, who is an internationally renowned expert in plant PCD (5, 6). This project will provide training in a variety of areas, including genetics and cell biology; the student will also benefit from a fully funded placement (12 months) at the VIB-PSB department in Ghent (http://www.psb.ugent.be), one of the world-leading plant science institutes.