Characterisation of high provitamin A (beta carotene) fruits and vegetables

Vitamin A deficiency (VAD) remains a global health problem. It is the leading cause of preventable blindness in young children, can compromise immune function and exacerbates childhood diseases. If left untreated, VAD has fatal consequences. The prevalence of VAD remains high in Low middle Income Countries (LMICs), while children’s consumption of vitamin-A rich foods and vitamin A supplements remains relatively low. Staple starchy crops are not suitable for the formation and accumulation of nutritional carotenoids such as b-carotene (Drapal et al., 2022 phytochemistry, 203, 113403). The laboratory at RHUL has developed tools and resources for the development of high provitamin A tomato fruits (e.g., https://www.burpee.com/tomato-vivacious-hybrid). A number of alleles in candidate genes have been identified. This has led to the development of molecular markers that have been used in breeding. The present project will focus on the underlying molecular mechanisms that facilitate the formation and accumulation of beta carotene in tomato fruits.  

The proposed PhD programme is focused on the underlying molecular and biochemical mechanisms associated with the biosynthesis and sequestration of beta carotene. Using diverse germplasm, the project will develop lines with further enhanced beta carotene and other quality traits. These lines will be characterised using transcriptomic and metabolomics to ascertain the holistic changes that facilitate cellular adaption (DOI. 10.1101/2023.01.09.523254) for the accumulation of beta carotene ((DOI.

10.1101/2023.01.05.522848). Transcriptomic and metabolomic analysis will be used to ascertain how the lines enable the formation at a holistic cellular level but enzyme characterisation of the identified candidates will also be carried out. Finally, gene editing to create precision breed lines to validate the alleles identified will be carried out. There is scope for the candidate to take the project in directions of their interest as this is an internally funded project.  

The applicants’ laboratory is a vibrant multidisciplinary activity, well equipped, and funded environment. The laboratory is an active participant in EU COST ACTIONS. The group has dedicated analytical and preparative apparatus as well as cultivation resources to perform the project. Training can be provided for all aspects of the experimental work, which will provide the candidate with an excellent experimental skillset. The laboratory and institute promote and adheres to EDI guidelines.