Skip to Main content Skip to Navigation
Theses

Nano-imagerie corrélative de fluorescence X synchrotron et de super résolution des métaux et des protéines dans les synapses de neurones d’hippocampe

Abstract : Metallic chemical elements such as Fe, Cu or Zn are present in minute quantities in the brain. The role of these trace metals in neuronal functions such as synaptic transmission and memory processes remains largely unclear. Moreover, metal dyshomeostasis is found in many neuropathologies, such as Alzheimer’s disease, Parkinson’s or amyotrophic lateral sclerosis. The interaction mechanisms of trace metals at the neuronal level are difficult to describe because of the lack of analytical methods with appropriate resolution and sensitivity to determine metal distribution at the synaptic level. Synchrotron X-ray fluorescence spectrometry (SXRF) is a multielemental chemical analysis method for describing the quantitative distribution of these elements at the sub-cellular scale with a nanometric resolution (40 nm at ESRF beamline ID16A ) and a very high sensitivity. In order to accurately interpret chemical imaging results, we have developed a protocol to correlate nano-SXRF imaging with stimulated emission depletion super resolution microscopy (STED), allowing the correlation of metal distribution and that of target proteins in super resolution. We labeled microtubules and F-actin of primary rat hippocampal neurons and imaged the cytoskeleton by STED microscopy before determining the distributions of P, S, Fe, Cu and Zn by SXRF spectrometry. We evidenced the colocalization of Zn and microtubules at the dendritic level and a localization of Cu mainly in the neck of dendritic spines rich in F-actin, and a distribution of Fe in the form of very localized points in the dendrites. These results highlight the crucial role of Zn in cytoskeleton architecture of hippocampal neurons and the developed correlative imaging method opens new perspectives for the study of metal dyshomeostasis in neurodegenerative diseases.
Document type :
Theses
Complete list of metadatas

Cited literature [215 references]  Display  Hide  Download

https://tel.archives-ouvertes.fr/tel-02363022
Contributor : Abes Star :  Contact
Submitted on : Thursday, November 14, 2019 - 10:56:23 AM
Last modification on : Tuesday, May 26, 2020 - 3:17:33 AM
Long-term archiving on: : Saturday, February 15, 2020 - 1:43:18 PM

File

DOMART_FLORELLE_2019.pdf
Version validated by the jury (STAR)

Identifiers

  • HAL Id : tel-02363022, version 1

Collections

Citation

Florelle Domart. Nano-imagerie corrélative de fluorescence X synchrotron et de super résolution des métaux et des protéines dans les synapses de neurones d’hippocampe. Chimie analytique. Université de Bordeaux, 2019. Français. ⟨NNT : 2019BORD0185⟩. ⟨tel-02363022⟩

Share

Metrics

Record views

172

Files downloads

162