Missions

-----This project proposes to use state-of-the-art experimental approaches to characterize the Dorsal Diencephalic Conduction system (DDC), a neuronal network mediating the development of aversive internal emotional states in response to negatively-valued challenges from the external environment.
The Medial Habenula (MHb) and the Interpeduncular Nucleus (IPN) are key relay nuclei belonging to the DDC. The synaptic connections linking the MHb with its unique postsynaptic target, the IPN, are known to regulate complex behaviors such as depression, anxiety, fear, sensitivity to pain, drug addiction and withdrawal. These important functions notwithstanding, most of the synaptic and circuital mechanisms of the MHb-IPN axis remain unknown. The dysfunction of these nuclei is tightly associated with altered emotional conditions, thus probably explaining the importance of the MB-IPN axis in regulating emotional associations.
It is generally assumed that increases in activity along the MHb-IPN axis leads to a depression of downstream serotoninergic and dopaminergic systems. Nevertheless, the influence of the MHb in controlling behavior appears to be subtler, as recent data demonstrate a bi-directional regulation of aversion by the DCC. We believe that this ambiguity may derive, at least in part, from the specific properties of the synapses of the circuit(s) involving the MHb. In particular, the synapses between the MHb and the IPN show many unusual properties, including a potentiation triggered by the activation of Gi/o protein-coupled receptors (like GABAb and µ opioid ones) that are unique for the central nervous system. Activation of these receptors on MHb axonal terminals indeed leads to a dramatic increase in synaptic efficacy, a property that contrasts with what is universally regarded as a ubiquitous presynaptic inhibitory action of the receptors.
The aim of this post-doctoral research project, performed in murine models, will be to characterize the circuit between the MHb and the IPN using a vast array of investigation techniques including morphological and ex vivo electrophysiological approaches, and in vivo behavioral and calcium imaging analyses.

Activités

Our team has long-standing expertise in a wide spectrum of investigative techniques ranging from ex vivo electrophysiology and morphological circuit tracking, to in vivo behavioral analysis, which led us to unveil several novel features of habenular physiology (Otsu, et al., 2019 Science). We seek to recruit a motivated candidate with the ultimate goal of combining ex-vivo electrophysiological and anatomical techniques, and in vivo behavioral and imaging approaches to reveal modulating the activity of GABAb receptors affects hedonic balance and emotional responses to environmental challenges.

Compétences

Candidates are expected to have knowledge, experience, and confirmed skills with electrophysiological recordings and analysis, rodent behavioral studies, anatomical tract tracing and/or imaging.
The ideal candidate should have a Ph.D. degree in neuroscience, physiology, or a related field (preferably obtained within the past five years). Candidates should be highly motivated, energetic, able to work independently and in collaboration.

Contexte de travail

The hosting institute, the Saints Pères institute for Neurosciences at the University of Paris (formally University Paris Descartes), has a long-established history of high-level neuroscientific research, centered on the application of avant-garde optical techniques to the study of brain physiology. The presence in loco of a core of researchers developing in vivo techniques like 2-photon imaging, miniscope GRIN lens-based imaging and fiber photometry also promises to offer a highly motivating and collaborative working environment. Situated in downtown Paris, in the renowned area surrounding the Saint-Germain-des-Près neighborhood, this postdoctoral position promises to associate a highly motivating scientific environment to an exciting cosmopolitan setting.

Contraintes et risques

N.A.