PolyProbe is submitted as the continuation of the project MUSIC (Multisensing polymer transistors for in vivo recording), in which we developed implantable microarrays capable of simultaneous recording of electrophysiology and metabolism. MUSIC has been particularly successful. Among its achievements was the use, for the first time, of a transistor to record brain activity. We demonstrated that using a transistor, as opposed to an electrode, yields recordings with exceptionally high signal-to-noise ratio. In PolyProbe we propose the integration of these transistors with organic electronic ion pumps, a recently-invented device capable of drug delivery with exquisite spatiotemporal accuracy. The resulting probe will allow the simultaneous recording from an exceptionally large number of neurons and, at the same time, provide the ability to interfere with neural circuits at a local scale. As such it promises to have a significant impact on neuroscience research by providing unique opportunities in physiology (understanding cognitive processes under physiological conditions) and pathology (diagnosing and treating of epilepsy). The EMSE partner, with expertise in organic bioelectronics and microfabrication will lead the prototyping of the probe. The AMU partner, with expertise in cognition and epilepsy, will provide validation in rats. They will use the probe to explore the mechanisms underlying the dynamics of functional connectivity maps in the hippocampus of control and epileptic rats. The inhibitory transmitter GABA will be pumped out on demand to try to interfere with epilepsy. The corporate partner, Microvitae, will be closely involved in both tasks and will design the electronic interface and pursue the commercialization of the probes for basic research applications.

MicroRNAs (miRNAs) are small regulatory RNAs previously thought not to be transcribed into polypeptides. We have recently shown that in plants primary transcripts of miRNAs encode and direct the synthesis of small, regulatory peptides, which we call miRNA-encoded peptides (miPEP)s (Lauressergues et al., 2015, Nature). MiPEPs are produced naturally by plants and enhance specifically the expression of their corresponding miRNAs. Moreover, external application of synthetic miPEPs to plants by watering or spraying increases the expression of miRNAs. This discovery of miPEPs has revealed the existence of a world of peptides more diverse and complex than previously thought, and probably with numerous important biological roles. The purpose of this project is to investigate this world of miPEP biology. We propose to analyse the molecular mechanisms underlying the effects of miPEPs as well as to develop methods to identify and analyse the diversity of small peptides in plants and animals. Finally, miPEPs provide a unique tool to attribute functions to all miRNAs in plants, and analyse the conservation of their functions in phylogenetically distant plants. Because miRNAs are involved in most developmental and pathological processes in plants and animals, manipulating their expression with exogenously applied specific peptides could have many applications. A long term objective of this project is then to explore the agronomical and therapeutic potential of miPEPs.

Most breakthroughs in our understanding of the basic mechanisms of information processing in the brain have been obtained with local field potentials (LFPs) and single neuron recordings in freely moving animals. Up until now these recordings have been performed with silicon probes and/or tetrodes, which capture the electrical fields generated by the flux of ions through ion channels localized in the cell membrane. The technology of silicon probes or tetrodes suffers from several limitations, which slow down the process of furthering our understanding of brain function. A technological breakthrough is now necessary, to drive the field to another level of possibilities. In particular, it is crucial to design multimodal technologies facilitating the harvesting of a maximum of the different signatures of network activity, and to decrease the invasiveness of the recording devices. The purpose of MUSIC is to develop a new generation of chronically implantable biocompatible probes displaying multi-sensing recording sites. MUSIC will make use of the most recent technology to address these issues: It will use organic electrochemical transistors which have recently been demonstrated as highly sensitive ion-to-electron converters. As such, they can measure ionic currents through ion channels with high fidelity, enabling a new mode of probing brain function. Moreover, these devices can be functionalized by appropriate biorecognition elements to yield biosensors for a variety of analytes, including metabolites such as glucose. MUSIC will make available an advanced biomedical tool that will have a major impact on neuroscience research. In this sense, it is not purely a technological project. The Inserm partner is interested in information processing in temporal lobe structures during spatial memory tasks in physiological and pathological (epilepsy) conditions. Epilepsy is the second neuronal disorder after migraine; it affects 1-2% of the population worldwide. The Inserm partner already uses the technology described above, i.e. silicon probes and tetrodes. In epilepsy, the limitations of these techniques become very important. The design of these new probes will allow for the first time to investigate the relationship between energy utilization and electrical activity in situ at the microscopic scale in physiological and pathological conditions. MUSIC brings together three partners who are at the forefront of their respective fields: The team at Ecole des Mines de Saint Etienne, with expertise in organic electronics and microfabrication, the epilepsy group of INSERM UMR 751, which will validate the probes and use them for leading research in epilepsy, and Microvitae Technologies, with expertise in design and fabrication of wireless electrophysiological data acquisition systems and commercialization of biomedical technologies.

Expansion of some harmful root parasitic weeds (Striga, orobanche, and Phelipanche species) in numerous economically important crops is becoming more than worrying and is a serious threat to food security in some area of Africa. If we consider the broomrape species Orobanche cumana, it causes important losses to the production of sunflower seed in countries surrounding the Black Sea, in Southern Europe and now in growing area of France. Unfortunately, no sustainable or efficient methods to control these various root parasitic weeds are presently available. O. cumana is a holoparasite devoid of chlorophyll which is unable to carry out photosynthesis and totally relies on its host for its water, mineral, and carbohydrate supplies. Like for other species of Orobanchaceae, two key steps must be completed by this weed for establishing parasitic interaction. It must perceive specific molecular signals produced by host roots in order for its seeds to germinate, and it must develop a novel specific organ, the haustorium, to invade host root tissues and connect to host vascular system. The molecular processes underlying these two steps are largely unknown. Progress has been hampered by the lack of genomic resources in orobanche and the lack of protocols allowing reverse genetics. The objectives of the proposed project are i) to develop new molecular tools to investigate the two main steps of parasitic development and ii) to develop an innovative and sustainable biocontrol technology for management of these Orobanchaceae pests. One partner of the project has discovered a new class of regulatory peptides, the miPEPs, which will play a pivotal role in the project. These peptides are encoded by primary transcripts of miRNAs. Each miPEP stimulates the transcription of its own encoding transcript, leading to the production of higher amount of the corresponding miRNA and consequently to a downregulation of specific target genes. This natural molecular regulation of gene expression can be obtained with synthetic miPEPs, so that specific stages of plant development can be perturbed temporally by exogenous treatment with appropriate miPEPs. The project will consist in two main Tasks: Task 1: to identify O. cumana miPEPs potentially involved in the regulation of seed germination/haustorium formation of O. cumana (based on RNAseq data already available and RACE-PCR analyses), to identify sunflower miPEPs most likely involved in regulating sunflower immunity (based on RNAseq data), to produce the corresponding synthetic candidate peptides and to assess the activity of O. cumana synthetic miPEPs on seed germination and haustorium differentiation (using specific and original in vitro assays). Task 2: to select the synthetic O. cumana and sunflower miPEP candidates and evaluate their capacity to negatively affect parasitism by either decreasing broomrape growth and infection or improving sunflower resistance (using in vivo pot culture assays), and in the light of the obtained results to define the miPEPs capable of controlling two other parasitic plant – plant interactions: Phelipanche ramosa – oilseed rape and Striga hermonthica – maize. The expected result of Task 1 is to increase our knowledge on key molecular mechanisms underlying a complex parasitic interaction by discovering important genes of O. cumana and sunflower which are involved in broomrape parasitism. The expected results of Task 2, to be exploited by a startup company, will be to provide a new phytosanitary method to control broomrape (and possibly witchweed) parasitism with highly specific and biodegradable natural substances.

The major reason for the high rate of rejection of myoelectric prostheses after upper arm amputation is the unnatural control of the hand and wrist functions as well as the limited number of degrees of freedom (DoF) of the prosthesis. No solution has ever been proposed based on the natural neuromuscular reorganization after amputation leading to a mobile phantom limb in 77% of upper limb amputees. It had been shown that phantom movements are associated to specific activities of residual limb muscles according to the type of performed phantom movement. Interestingly, we found that neuromuscular reorganization gives rise to the genesis of functionally distinct muscle volumes within the same muscle, i.e., muscle volumes that are distinctly and independently active as function of the type of phantom movement. If we use these patterns of activation of the distinct muscle volumes to make the prosthesis mimicking the executed phantom movement, the control would be natural for the patients and the number of controllable active DoF of the prosthesis might potentially increase. So, the main goal of PhantoMovControl is to outreach the actual limits of myoelectric upper-arm prostheses by using high-resolution EMG associated with phantom movements, favouring a natural and intuitive control of prosthetic devices (thus without heavy training/learning) with a high number of DoF. Our main ambition is to develop within 3 years a “control kit” for existing polydigital hand prostheses and to rapidly transfer this approach to both clinic and to prosthesis industry. This control kit must integrate arrays of electrodes that can be placed on the residual limb within the socket of the prosthesis (thus ultra-thin, cable free, and fixed on an extensible support), as well as an embedded computer module that classifies muscle activity associated with phantom movements and controls in real time the polydigital prosthesis. Multi-electrode arrays are used in the literature and some are commercially available, but they do not fulfil our requirements. Therefore, we integrated an industrial partner able to design and produce such electrodes arrays to our academic consortium in order to accelerate the transfer of our new control approach to a concrete implementation by prosthetics companies in their products. In order to make our bio-inspired control approach robust and adaptable to intra- and inter-patient variability, we’ll have to progress in parallel at a fundamental level. We’ll study the neuromuscular reorganization after amputation and gather knowledge about the robustness of the EMG during different types of phantom movements (e.g., combined with residual limb movements, fast or slow…) and their evolution in time and following phantom movement training. Moreover, we’ll study the socio-anthropological and cultural phenomena influencing the appropriation of these technical objects in order to ease the appropriation by the patients of such myoelectric prostheses and reduce the rate of rejection of upper-limb prostheses. To ensure the multidisciplinarity of our approach, partners from Human and Social Sciences, Neurosciences and Engineering were gathered into the project. The consortium consists of 3 scientific (ISM, ISIR, CETCOPRA), 1 clinical (IRR) and 1 industrial partner (Microvitae), closely interacting in 5 Work Packages. Requested resources include an engineer to assist in the development of the EMG classifier and the “control kit” (ISIR), a postdoctoral researcher for studying the robustness of the EMG and its evolution after training (ISM), a prosthesist and an occupational therapist for adaptation of the prosthesis and its functional evaluation (IRR). We take up the challenge that this new control approach will function symbiotically with the underlying neuroplasticity, hereby stabilizing the control of the phantom movements and the associated EMG (and thus of the prosthesis) and increasing the appropriation by the patients of such technology.