Dynamics of second messengers in axon guidance: decrypting the codes

Objective

The mature nervous system is an intricate network in which neurons are connected to specific partners. The construction of the network requires directed growth of axons towards their appropriate targets during development and during neuronal regeneration after a lesion. Axons must navigate through a complex environment where they are guided by a combination of attractive and repulsive molecules. Cellular second messengers, particularly calcium and cyclic nucleotides – cyclic adenosine monophosphate (cAMP) and cyclic guanosine monophosphate (cGMP) – are critical for responses to guidance molecules and axonal pathfinding. Recently, the temporal structure of calcium signals has been shown to have a key role in regulating growth cone behaviors, but the temporal components of cAMP and cGMP signals are largely unknown. The present project proposes to investigate the involvement of second messengers during the midline crossing of spinal commissural axons in vivo. We will first identify the crucial second messengers for the guidance of those axons in the Xenopus spinal cord in vivo. Second, we will use newly improved cyclic nucleotide FRET probes and fluorescent calcium sensors to determine the temporal dynamics of cAMP, cGMP and calcium signaling (the frequency of transients and sustained variations in their intracellular concentrations) in vivo in the growth cones of spinal commissural interneurons. We will then investigate the respective roles of temporally restricted and sustained variations of second messengers in the guidance of commissural axons in vivo, by imposing different frequencies of transient or sustained perturbations of cAMP, cGMP and calcium. Finally, we will investigate the interdependence of these signaling pathways by imaging one second messengers while manipulating another. These studies will substantially advance our understanding of signaling necessary for axonal pathfinding by spinal cord neurons.

Fields of science (EuroSciVoc)

CORDIS classifies projects with EuroSciVoc, a multilingual taxonomy of fields of science, through a semi-automatic process based on NLP techniques. See: https://op.europa.eu/en/web/eu-vocabularies/euroscivoc.

• natural sciences biological sciences neurobiology
• natural sciences chemical sciences inorganic chemistry alkaline earth metals
• engineering and technology electrical engineering, electronic engineering, information engineering electronic engineering sensors
• natural sciences biological sciences genetics nucleotides

Keywords

Project’s keywords as indicated by the project coordinator. Not to be confused with the EuroSciVoc taxonomy (Fields of science)

• FRET
• axon guidance
• cAMP
• calcium
• developmental biology
• in vivo imaging
• neurobiology
• spinal cord

Programme(s)

Multi-annual funding programmes that define the EU’s priorities for research and innovation.

• FP7-PEOPLE - Specific programme "People" implementing the Seventh Framework Programme of the European Community for research, technological development and demonstration activities (2007 to 2013)

Topic(s)

Calls for proposals are divided into topics. A topic defines a specific subject or area for which applicants can submit proposals. The description of a topic comprises its specific scope and the expected impact of the funded project.

• PEOPLE-2007-4-1.IOF - Marie Curie Action: "International Outgoing Fellowships for Career Development"

Call for proposal

Procedure for inviting applicants to submit project proposals, with the aim of receiving EU funding.

FP7-PEOPLE-2007-4-1-IOF
See other projects for this call

Funding Scheme

Funding scheme (or “Type of Action”) inside a programme with common features. It specifies: the scope of what is funded; the reimbursement rate; specific evaluation criteria to qualify for funding; and the use of simplified forms of costs like lump sums.

MC-IOF - International Outgoing Fellowships (IOF)

Coordinator