Analysis of Heat Shock Factor dynamics using fluorescence microscopy
type: Dataset
description: The majority of studies made on transcription factors dynamics on living cells agree with a fast dynamics process. However, there is some exceptions such as the dynamics of the transcription factor HSF “Heat Shock Factor” on drosophila polytenic chromosome. My project is to study HSF1 dynamics in human living cells. Cells exposure to a stress such as heat shock induces a transient and ubiquitous response that function's to protect cells against the deleterious effect of stress. During the course of a heat shock, several phenomenons take place: i) a global arrest of transcription, with the exception of some genes, such as those coding for the heat shock proteins (hsp), which expression is under the control of HSF1. ii) Activation of HSF1 that relocalize in a fast and transient way to nuclear stress bodies (nSBs), where it induces satellite III transcription. nSBs act as a natural amplification gene array, visible on microscopy. We have used two complementary techniques to look at HSF1 dynamics in living cells: Fluorescence recovery after photobleaching (FRAP) and multiconfocal fluorescence correlation spectroscopy (mFCS) that allow FCS analysis at several position simultaneously. On HeLa cells, HSF1-eGFP protein has a fast dynamics which is significantly slowed down following heat shock. On mFCS, we obtained a diffusion constant of 14 µm²/s before heat shock, and 10 µm²/s after heat shock. On FRAP, the half recovery time is 0.2 s before heat shock, 2.6 s after heat shock in the nucleoplasm and 65 s in nuclear stress bodies. HSF1 dynamics slowing down may be explain by two phenomenons: i) formation of high molecular mass complexes, ii) rise of interaction of HSF1 with chromatin. To better characterize changes in HSF1 dynamics after heat shock, several mutants have been analyzed. The trimerization domain of HSF1 is essential for dynamics changes after heat shock, while DNA binding domain (DBD) and transactivation domain (TAD) have only little effects on dynamics change…
landing page: https://theses.hal.science/tel-00771403
identifier: NNT: 2012GRENV030
keyword: dynamics
keyword: dynamique
keyword: fcs
keyword: fluorescence-microscopy
keyword: frap
keyword: hsf1
keyword: infoeu-reposemanticsdoctoralthesis
keyword: microscopie-de-fluorescence
keyword: sdvsalife-sciences-q-bioagricultural-sciences
keyword: theses
issued: 2026-05-15T12:13:55.350352
modified: 2026-05-15T12:13:55.350357
language: fr
contact point: Organization
  fn: CCSD

test_moissonnage_selune
type: Agent

Analysis of Heat Shock Factor dynamics using fluorescence microscopy
type: Distribution
format: HTML
access URL: https://theses.hal.science/tel-00771403
issued: 2026-05-15T12:13:55.389327
modified: 2026-05-15T12:13:55.325618