ERC FUNDED PROJECTS

Cell volume regulation is crucial for any living cell because changes in volume determine the metabolic activity through e.g. changes in ionic strength, pH, macromolecular crowding and membrane tension. These physical chemical parameters influence interaction rates and affinities of biomolecules, folding rates, and fold stabilities in vivo. Understanding of the underlying volume regulatory mechanisms has immediate application in biotechnology and health, yet these factors are generally ignored in systems analyses of cellular functions. My team has uncovered a number of mechanisms and insights of cell volume regulation. The next step forward is to elucidate how the components of a cell volume regulatory circuit work together and control the physicochemical conditions of the cell. I propose construction of a synthetic cell in which an osmoregulatory transporter and mechanosensitive channel form a minimal volume regulatory network. My group has developed the technology to reconstitute membrane proteins into lipid vesicles (synthetic cells). One of the challenges is to incorporate into the vesicles an efficient pathway for ATP production and maintain energy homeostasis while the load on the system varies. We aim to control the transmembrane flux of osmolytes, which requires elucidation of the molecular mechanism of gating of the osmoregulatory transporter. We will focus on the glycine betaine ABC importer, which is one of the most complex transporters known to date with ten distinct protein domains, transiently interacting with each other. The proposed synthetic metabolic circuit constitutes a fascinating out-of-equilibrium system, allowing us to understand cell volume regulatory mechanisms in a context and at a level of complexity minimally needed for life. Analysis of this circuit will address many outstanding questions and eventually allow us to design more sophisticated vesicular systems with applications, for example as compartmentalized reaction networks.

2 247 231 €

Start date: 2015-07-01, End date: 2020-06-30

In an era of rapid climate change there is a pressing need to understand whether and how organisms are able to adapt to novel environments. Such understanding is hampered by a major divide in the life sciences. Disciplines like systems biology or neurobiology make rapid progress in unravelling the mechanisms underlying the responses of organisms to their environment, but this knowledge is insufficiently integrated in eco-evolutionary theory. Current eco-evolutionary models focus on the response patterns themselves, largely neglecting the structures and mechanisms producing these patterns. Here I propose a new, mechanism-oriented framework that views the architecture of adaptation, rather than the resulting responses, as the primary target of natural selection. I am convinced that this change in perspective will yield fundamentally new insights, necessitating the re-evaluation of many seemingly well-established eco-evolutionary principles. My aim is to develop a comprehensive theory of the eco-evolutionary causes and consequences of the architecture underlying adaptive responses. In three parallel lines of investigation, I will study how architecture is shaped by selection, how evolved response strategies reflect the underlying architecture, and how these responses affect the eco-evolutionary dynamics and the capacity to adapt to novel conditions. All three lines have the potential of making ground-breaking contributions to eco-evolutionary theory, including: the specification of evolutionary tipping points; resolving the puzzle that real organisms evolve much faster than predicted by current theory; a new and general explanation for the evolutionary emergence of individual variation; and a framework for studying the evolution of learning and other general-purpose mechanisms. By making use of concepts from information theory and artificial intelligence, the project will also introduce various methodological innovations.

2 500 000 €

Start date: 2018-12-01, End date: 2023-11-30

Replacement of petrochemistry by bio-based processes is key to sustainable development and requires microbes equipped with novel-to-nature capabilities. The efficiency of such engineered microbes strongly depends on their native metabolic networks. However, aeons of evolution have optimized these networks for fitness in nature rather than for industrial performance. As a result, central metabolic networks are complex and encoded by mosaic microbial genomes in which genes, irrespective of their function, are scattered over the genome and chromosomes. This absence of a modular organization tremendously restricts genetic accessibility and presents a major hurdle for fundamental understanding and rational engineering of central metabolism. To conquer this limitation, I introduce the concept of ‘pathway swapping’, which will enable experimenters to remodel the core machinery of microbes at will. Using the yeast Saccharomyces cerevisiae, an industrial biotechnology work horse and model eukaryotic cell, I propose to design and construct a microbial chassis in which all genes encoding enzymes in central carbon metabolism are relocated to a specialized synthetic chromosome, from which they can be easily swapped by any – homologous or heterologous – synthetic pathway. This challenging and innovative project paves the way for a modular approach to engineering of central metabolism. Beyond providing a ground-breaking enabling technology, the ultimate goal of the pathway swapping technology is to address hitherto unanswered fundamental questions. Access to a sheer endless variety of configurations of central metabolism offers unique, new possibilities to study the fundamental design of metabolic pathways, the constraints that have shaped them and unifying principles for their structure and regulation. Moreover, this technology enables fast, combinatorial optimization studies on central metabolism to optimize its performance in biotechnological purposes.

2 149 718 €

Start date: 2015-09-01, End date: 2020-08-31

This research proposal explores the political economy of international development assistance (aid) directed towards social expenditures, examined through the lens of a particular financial quandary that has been ignored in the literature despite having important economic and political repercussions. The quandary is that aid cannot be directly spent on expenditures denominated in domestic currency. Instead, aid needs to be first converted into domestic currency whereas the foreign exchange provided is used for other purposes, resulting in a process prone to complex politics regarding domestic monetary policy and spending commitments. The implications require a serious rethink of many of the accepted premises in the political economy of aid and related literatures. It is urgent to engage in this rethinking given tensions between two dynamics in the current global political economy: a tightening financial cycle facing developing countries versus an increasing emphasis in international development agendas of directing aid towards social expenditures. The financial quandary might exacerbate these tensions, restricting recipient government policy space despite donor commitments of respecting national ownership. The proposed research examines these implications through the emerging social protection agenda among donors, which serves as an ideal policy case given that social protection expenditures are almost entirely based on domestic currency. This will be researched through a mixed-method comparative case study of six developing countries, combining quantitative analysis of balance of payments and financing constraints with qualitative process tracing based on elite interviews and documentary research. The objective is to re-orient our thinking on these issues for a deeper appreciation of the systemic political and economic challenges facing global redistribution towards poorer countries, particularly with respect to the forthcoming Sustainable Development Goals.

1 459 529 €

Start date: 2015-05-01, End date: 2020-04-30