Mark’s research focuses on the molecular biology underlying pea reproductive development, particularly fruit (pod) growth, in relation to nutritional profile.
Currently, Mark is attempting to identify the causative gene behind the blunt mutation in pea pods (which affects the shape of the pod tip) and to investigate if this mutation leads to alteration in nutrients, including resistant starch due to concomitant changes in pod valve photosynthesis.
Mark is also investigating hormonal signalling events in pea fruit development.
Pea, along with most legume relatives in the Fabeae and Trifolieae families, produces an unusual variant of auxin known as 4-chloroindole-3-acetic acid (4-Cl-IAA). This hormone differs from the canonical auxin (indole-3-acetic acid, IAA) in that it has a chlorine atom covalently attached at the 4′ position of its indole ring. 4-Cl-IAA has been detected primarily in reproductive tissues, where previous work indicates it may play a role in fruit growth and seed starch metabolism.
Excitingly, pea fruit differ in their responses to exogenously applied IAA and 4-Cl-IAA, and so the molecular basis of this discriminating ability is one of our key interests. In addition, we are interested in identifying the gene that results in the production of 4-chlorotryptophan (a precursor to 4-Cl-IAA) to allow for CRISPR/Cas9-mediated knockout and genetic assessment of the contribution of 4-Cl-IAA to plant reproductive physiology.
The ultimate aims of Mark’s project is to better elucidate the signalling events that occur between parent and offspring within pea fruit, with a view towards targeted manipulation of this system to improve the nutritional value of peas.