The enormous diversity of neural cell types is a defining characteristic of the brain. Different neural circuits consist of a myriad of distinct cell types, each with specific intrinsic properties and patterns of synaptic connectivity, which transform neural input and convey this information to downstream targets. However, despite their fundamental importance in neural processing, our understanding of how individual cell types differentially contribute to neural circuit function and computation remains poor. Here, the investigators leverage a highly tractable neural circuit, the mouse olfactory (piriform, PCx) cortex, to determine how information about odor stimuli is encoded, transformed, and conveyed to its different downstream target areas. The objective of this proposal is to register diverse odor responses observed in PCx neurons onto identified neural cell types, defined by their morphology, intrinsic properties, and connectivity. This will be achieved via a collaborative, multidisciplinary, iterative computational-experimental approach, involving computational modeling, in vivo two-photon imaging, in vitro electrophysiology, behavior, chemogenetics and decoding analyses. The investigators? working hypothesis is that different features of an odor ? its identity, intensity, and valence ? are selectively extracted and encoded by distinct subsets of PCx neurons by virtue of their different intrinsic and local circuit properties, and then selectively transmitted to different target areas. In the two aims proposed, the investigators will image activity evoked by different odorants at multiple concentrations in subpopulations of PCx neurons in awake, behaving mice. They will compare their imaging data with simulated odor-evoked activity in a computational model in which they incorporate the specific intrinsic properties and patterns of local synaptic connectivity of these subpopulations of PCx neurons. In Aim1, the investigators will image and model odor responses in two morphologically distinct subtypes of principal neurons, semilunar cells and superficial pyramidal cells. In Aim 2 they use a similar approach, but with subpopulations of PCx neurons defined by their specific projection targets. Mice will be performing a go/no go odor discrimination task during imaging, allowing characterization of responses to odors with different identities, concentrations or valence. This experimental-computational approach will determine the extent to which the distinct intrinsic properties and specific connectivity patterns of different cell-types accounts for differences in their odor responses. Crucially, mismatches between modeling and experimental results will reveal additional properties of these cells and circuitry that may determine their odor responses, which they can and will test experimentally. Achieving the goals of this proposal will therefore provide a coherent framework for understanding how different features of an odor stimulus can be selectively extracted, encoded and conveyed to appropriate downstream targets.

The ability to integrate multiple environmental parameters is key for plant survival. On the one hand, iron (Fe) is an essential micronutrient for all living organisms. However, low Fe bioavailability in soils often limits plant growth. On the other hand, plants are constantly challenged by pathogens and have developed an immune system to resist infections. Perturbation of Fe homeostasis is a major strategy in host-pathogen interactions. However, direct molecular connections between the Fe homeostasis network and the plant immune system have not yet been established. Based on the recent identification of a mutation in NRG1, a receptor of the plant immune system, in a screen for tolerance to Fe deficiency, the project will explore the cross-talk between the immune system and the Fe homeostasis network using a combination of molecular genetics, biochemistry, ionomics, transcriptomics and metabolomics. The response of mutants affected in NRG1 and other components of the immune system to Fe deficiency will be characterized. Reciprocally, the response of mutants affecting regulators of Fe homeostasis to pathogen challenge will be studied. NRG1 function and its genetic and physical interactions with components of the Fe homeostasis network will be analyzed. This is expected to shed light on the molecular connections between immunity and Fe nutrition. The partnership involving teams working on metal homeostasis, plant-pathogen interaction and signaling provides all the necessary expertise to successfully implement the project. The outcome of the project should open new perspectives for developing wide-spectrum plant protection against pathogens, while improving concomitantly plant tolerance to Fe deficiency.

The overarching objective of FutureWeb is to produce robust projections of the impacts of global change on multi-trophic biodiversity, ecosystem functioning and services in Europe. We will engage with stakeholders early in the project to select the most appropriate scenarios analyses for developing biodiversity management strategies and conservation plans, and to identify relevant biodiversity variables. From this, FutureWeb will first produce on harmonized set of available data across Europe (species distribution data, species trait data, species interaction data) for all European vertebrates, as well as high resolution climatic and land use layers for both current and future conditions. Second, we build the first multi-trophic species distribution model that will allow both deriving individual species predictions and diversity estimates. We will apply this novel model on all vertebrate species and project the potential distributions an ensemble of climate and land use scenarios. The final biodiversity ensembles will not only account for the uncertainty given the biodiversity models and data, but also will build on a large range of regional climate models, the full set of representative concentration pathways and the shared socio-economic pathways scenarios of land use change. Third, we will integrate ecosystem functioning in the ensemble predictions via the total energy flux between functional feeding guilds as a measure of multitrophic ecosystem functioning. These will be based on metabolic scaling theory and principles of food- web energy dynamics. In addition to the total energy flux, we will focus on specific functions and services provided by vertebrates. Finally, I will apply novel conservation prioritization approaches that will take multi-trophic biodiversity, ecosystem multi-functionality and bundles of services into consideration. FutureWeb is thus at the forefront of research predicting biodiversity changes in response to global change, their cascading effects on ecosystem functioning and services and the conservation implications of those changes.