ERC FUNDED PROJECTS

Cells must integrate output from multiple genetic circuits in order to correctly control cellular processes. Despite much work characterizing regulation in these circuits, how circuits interact to control global cellular programs remains unclear. This is particularly true given that recent research at the single cell level has revealed that genetic circuits often generate variable or stochastic regulation dynamics. In this proposal we will use a multi-disciplinary approach, combining modelling and time-lapse microscopy, to investigate how cells can robustly integrate signals from multiple dynamic genetic circuits. In particular we will answer the following questions: 1) What types of dynamic signal encoding strategies are available for the cell? 2) What are the benefits of dynamic gene activation, whether stochastic or oscillatory, to the cell? 3) How do cells couple and integrate output from diverse gene modules despite the noise and variability observed in gene circuit dynamics? We will study these questions using 2 key model systems. In Aim 1, we will examine stochastic pulse regulation dynamics and coupling between alternative sigma factors in B. subtilis. Our preliminary data has revealed that multiple B. subtilis sigma factors stochastically pulse under stress. We will look for evidence of any coupling or interactions between these stochastic pulse circuits. This system will serve as a model for how a cell uses stochastic pulsing to control diverse cellular processes. In Aim 2, we will examine coupling between a deterministic oscillator, the circadian clock, and multiple other key pathways in Cyanobacteria. We will examine how the cell can dynamically couple multiple cellular processes using an oscillating signal. This work will provide an excellent base for Aim 3, in which we will use synthetic biology approaches to develop ‘bottom up’ tests of generation of novel dynamic coupling strategies.

1 499 571 €

Start date: 2014-02-01, End date: 2019-01-31

"My project consists of two lines of work. 1.Empirical Macro-Finance: Asset prices are informative about the macro-economic risks that matter to investors and about the welfare costs of economic fluctuations. However, recent empirical evidence suggests that leading asset pricing models cannot explain how risks are priced across maturities in equity markets, which is a key input to measuring the costs of business cycles. An analysis of what leading models miss will vastly improve our understanding of how the real economy and asset prices are related. Also, by expanding our empirical evidence about the term structure of equity to the firm-level, I plan to study how investment decisions relate to asset prices. My goal is to measure the firms' incentives to invest and how this impacts economic growth more broadly. 2.Financial Economics of Insurance Markets: Households in Europe and the US can choose from a wide variety of insurance products that insure health and mortality risks. Choosing between these products is no easy task and the costs from sub-optimal insurance choices are estimated to be large. My plan is to develop a comprehensive life-cycle theory of insurance choice that accounts for family structure, risk factors such as labor income and housing, and different institutional settings across countries. I also plan to study the supply side of insurance markets. The traditional view is that insurance prices are driven by life-cycle demand or informational frictions. However, as is clear from evidence during the financial crisis, insurance companies are in fact financial institutions. If financial constraints bind, it may affect insurance prices and ultimately consumers' welfare. My goal is to understand how financial frictions affect insurance companies. A policy implication of my research may be that the private supply of insurance is an imperfect substitute for public supply as insurance companies face different incentives and constraints than the government."

1 077 765 €

Start date: 2013-10-01, End date: 2018-09-30

This proposal covers three research strands at the intersection of innovation economics, economic history, and labour economics. In project A I will investigate how the number of entrepreneurs at the city level affects city growth. As the number of entrepreneurs in a city is likely to be endogenous I identify the causal effect of entrepreneurs using the exodus of Jewish entrepreneurs from German cities during the Nazi era. As different German cities were affected to varying extents by the exodus of Jewish entrepreneurs I can investigate how entrepreneurs affect local GDP and employment in the long-run. Furthermore, I will analyse which types of entrepreneurs matter (e.g. bankers versus manufacturers) because different cities lost Jewish entrepreneurs in different professions. In project B we will analyse how increases in the availability of secondary schools in Germany affect the number of talented people (such as scientists, parliamentarians or entrepreneurs) who originate from certain cities. To analyse the causal effect of secondary school availability we study large expansions in the number of schools in Germany that lowered the cost of attending an academic-track school for children in some locations, in particular for students in rural areas. Furthermore, we will investigate how the school curriculum and how single-sex versus mixed-sex education affect the production of talent. In project C we investigate the role of open science for the accumulation of knowledge. To investigate the causal effect of open science on the productivity of scientists we will investigate the exclusion of scientists from the losing Central Powers (e.g. Germany) from the international scientific community after WWI. As the exclusion affected scientists in different scientific fields and countries very differently we can identify the role of open science for the number of published articles by a certain scientist and how quickly she cites important work by foreign scientists.

733 621 €

Start date: 2013-11-01, End date: 2018-09-30

"A modern economy is an intricately linked web of specialized production units, each relying on the flow of inputs from their suppliers to produce their own output which, in turn, is routed towards other downstream units. Recent work in economics stresses that the structure of this production network is key in determining whether and how microeconomic shocks can propagate throughout the economy and shape aggregate outcomes. This project has two main goals. First, it aims to provide novel evidence that we can trace back the origins of business cycles and asset price fluctuations to individual technologies interconnected by input-supply relations. The particular questions it tries to answer are: (1) Can we have more direct, causal, evidence that these micro shocks do matter in practice for the evolution of aggregates? What are examples of these micro shocks in reality, how can we identify them and how do they propagate through input chains? (2) What are the asset pricing implications of this perspective on the micro origins of aggregate fluctuations? What is the relation between changes in the technology portfolio of an economy and the evolution of asset prices? The second aim of this project is to improve our understanding of the structure and evolution of these production networks by asking the following questions: (3) At the firm level, do more productive suppliers match with more productive customers and, if so, why? What is the typical duration of a supplier-customer match and does this vary across matches? What is the firm-level impact of matching with better suppliers or more productive customers? (4) How do inputs diffuse on a network of interconnected technologies? Do linkages across sectors facilitate input adoption and the diffusion of General Purpose Technologies? Can linkages across sectors help us understand not only which sectors will adopt a given input but also the order in which these sectors adopt it?"

940 200 €

Start date: 2014-05-01, End date: 2019-04-30