Evolution & Behaviour of Complex Systems

    I am fascinated by complex systems. Complex systems are more than the sum of their parts but how they function and come to be is often unclear. Throughout my career I have sought to understand the evolution & behaviour of these complex systems. I have very broad scientific interests but I am particularly fascinated by biological interactions and gene regulatory networks. I find many similarities between these complex systems and the legal world. Perhaps for this reason, I also have a passion for studying scientific policy and the regulation of biotechnology (such as GMOs).

Scientific Policy & GMO Regulation

    Novel biological systems have enormous potential to address many challenges facing the world, but to maintain public confidence these advances need to be developed and deployed in a carefully regulated manner. However, often regulatory law lags behind technological development and as such we, as scientists, need to excise care and be mindful of our potential impact. As part of this, I have an interest in the ongoing developments in the regulation of biotechnology. Previously I contributed to an examination of genetically modified mosquito releases. However, more recently, working with Dr Chris Reynolds, we proposed an outcome based regulatory framework for Australia - one that examines the final product not the technology used to build it. I will continue to contribute to the discussion of regulation through engagement, academic writing and my upcoming position with the World Mosquito Program as Senior Regulatory Officer.

Biological Interactions

Reproductive Communication
    Appropriate responses to the queues of other individuals is critical for any organism, but when you are your own germ line a simple mistake can spell the end of your lineage. Previously, I studied how baker’s yeast, Saccharomyces cerevisiae, uses appropriate pheromone signally to ensure mating with another compatible individual. In this work, through experimental evolution of the pheromone receptor STE2, we explored mating barriers between species and determined critical regions in the receptor that facilitate these barriers.
Modelling Mutualism
    Mutualism facilitates the exploitation of otherwise difficult environmental niches and is at the heart of numerous ecosystems. However, how these complex relationships evolve, are maintained and what happens when they breakdown is still poorly understood. In an on going collaboration with Chaitanya Gokhale, we explore these complex dynamics through the use of yeast systems and theoretical models.
We have recently published a review that examines the interface between theoretical and synthetic biologies, while asking the question — ‘Should we intervene in nature to stabilise failing mutualisms?’. Recently, we have completed work aimed at understanding the collapse of mutualism and are currently working towards developing novel systems for the modelling of mutualism.

Altering Inheritance
    Underdominance, wherein hybrids are weaker than either parent, is a powerful system that can facilitate the transformation of a whole population (also known as gene drive). I have previously contributed to work describing the development of a poison/rescue single locus gene drive in Drosophila melanogaster (fly). Together with a visiting research, we are now working towards developing this system for use in yeast. Although this may seem like a conceptual step backwards, the power of yeast is the rapid prototyping on the population dynamics and how choice of the gene targets (for the poison/rescue) influence these dynamics.

Gene Regulatory Networks

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Carbon Catabolite Repression
    Carbon catabolite repression (CCR) is a gene regulatory system whereby an organism can sequentially utilise carbon sources based on their available energy. For example, an organism can use environmental glucose before expressing genes required for the breakdown of more complex carbon sources like cellulose. This system have been widely studied in the model filamentous fungi Aspergillus nidulans but is also widely exploited for strain improvement programs in industrial fungi. Although I have a strong interest in how this system works and functions, my primary interest is applying this knowledge for strain improvement. Previously I generated a Trichoderma reesei strain that had greatly elevated enzyme production via the removal of a key CCR regulator (cre2). I am currently collaborating to further improve this strain.