Live cell microscopy analysis of radiation-induced DNA double-strand break motion

Jakob, Burkhard; Splinter, J.; Durante, Marco; Taucher-Scholz, G.

doi:10.1073/pnas.0810987106

Cited by 163 publications

(121 citation statements)

References 45 publications

Supporting

Mentioning

107

Contrasting

Order By: Relevance

“…Using soft X-rays generating tracks of DSB, Nelms and colleagues (Nelms et al, 1998) showed positional stability of DNA lesions. Similar conclusions were drawn from time-lapse measurements of 53BP1 repair foci (Kruhlak et al, 2006;Jakob et al, 2009) and from recordings of the position of broken DNA ends (Soutoglou et al, 2007). The decrease in …”

Section: Resultssupporting

confidence: 63%

Nanoscale histone localization in live cells reveals reduced chromatin mobility in response to DNA damage

Liu

Vidi

Lelièvre

et al. 2014

Journal of Cell Science

View full text Add to dashboard Cite

BSTRACTNuclear functions including gene expression, DNA replication and genome maintenance intimately rely on dynamic changes in chromatin organization. The movements of chromatin fibers might play important roles in the regulation of these fundamental processes, yet the mechanisms controlling chromatin mobility are poorly understood owing to methodological limitations for the assessment of chromatin movements. Here, we present a facile and quantitative technique that relies on photoactivation of GFPtagged histones and paired-particle tracking to measure chromatin mobility in live cells. We validate the method by comparing live cells to ATP-depleted cells and show that chromatin movements in mammalian cells are predominantly energy dependent. We also find that chromatin diffusion decreases in response to DNA breaks induced by a genotoxic drug or by the ISceI meganuclease. Timecourse analysis after cell exposure to ionizing radiation indicates that the decrease in chromatin mobility is transient and precedes subsequent increased mobility. Future applications of the method in the DNA repair field and beyond are discussed.

show abstract

Section: Resultssupporting

confidence: 63%

Nanoscale histone localization in live cells reveals reduced chromatin mobility in response to DNA damage

Liu

Vidi

Lelièvre

et al. 2014

Journal of Cell Science

View full text Add to dashboard Cite

show abstract

“…Although the decreasing foci numbers in the middle region roughly follow the theoretical prediction, the plateaus in the smaller and larger categories reflect expected experimental restrictions. The resolution of the focus structure with a typical size of roughly 0.5 μm and slight foci movement processes (37,38) (Fig. S2E) might contribute to the deviation from the 1/r 2 dependency below 0.4 μm, and also might give rise to a slightly steeper decrease than expected above 0.4 μm.…”

Section: Resultsmentioning

confidence: 99%

Direct measurement of the 3-dimensional DNA lesion distribution induced by energetic charged particles in a mouse model tissue

Mirsch

Tommasino

Frohns

et al. 2015

Proc. Natl. Acad. Sci. U.S.A.

View full text Add to dashboard Cite

Charged particles are increasingly used in cancer radiotherapy and contribute significantly to the natural radiation risk. The difference in the biological effects of high-energy charged particles compared with X-rays or γ-rays is determined largely by the spatial distribution of their energy deposition events. Part of the energy is deposited in a densely ionizing manner in the inner part of the track, with the remainder spread out more sparsely over the outer track region. Our knowledge about the dose distribution is derived solely from modeling approaches and physical measurements in inorganic material. Here we exploited the exceptional sensitivity of γH2AX foci technology and quantified the spatial distribution of DNA lesions induced by charged particles in a mouse model tissue. We observed that charged particles damage tissue nonhomogenously, with single cells receiving high doses and many other cells exposed to isolated damage resulting from high-energy secondary electrons. Using calibration experiments, we transformed the 3D lesion distribution into a dose distribution and compared it with predictions from modeling approaches. We obtained a radial dose distribution with sub-micrometer resolution that decreased with increasing distance to the particle path following a 1/r 2 dependency. The analysis further revealed the existence of a background dose at larger distances from the particle path arising from overlapping dose deposition events from independent particles. Our study provides, to our knowledge, the first quantification of the spatial dose distribution of charged particles in biologically relevant material, and will serve as a benchmark for biophysical models that predict the biological effects of these particles.C harged particles, including protons, α-particles, and heavy ions, are increasingly used in cancer radiotherapy and represent a significant component of the natural background irradiation on earth and in space (1-3). Their biological effect is often very different from that of photons (X-or γ-rays), largely because charged particles deposit their energy along a track, whereas photons produce a fairly homogeneous dose distribution. Linear energy transfer (LET; typically given in units of keV/μm) has been introduced as a parameter to describe the amount of energy that charged particles deposit along their track. Particles with high LET are densely ionizing and typically biologically more effective than photons or low-LET particles. Energy deposition along a particle track is not restricted to the path itself (the so-called "track core"), but extends laterally into an area known as the penumbra of the particle, which can reach considerable distances for high-energy particles. Energy deposition in the penumbra arises from energetic secondary electrons, so-called δ-electrons, which are generated by ionization events of the charged particles and carry energy away from the immediate path into the penumbra. According to classical track structure theory, ∼50% of the total energy is deposited in the...

show abstract

“…In this case, enhanced mobility requires 53BP1 and the INM proteins SUN1 and SUN2 (Dimitrova et al 2008;Lottersberger et al 2015). On the other hand, other studies have observed that chromatin containing DSBs exhibits limited mobility (Kruhlak et al 2006;Soutoglou et al 2007;Jakob et al 2009). This apparent discrepancy may be attributed to the type of damage incurred and/or to the way it activates the ATM/ATR checkpoint, which was shown in yeast to contribute to DSB motion (Seeber et al 2013).…”

Section: Increasing Mobility: a Functional Requirement For Homology Smentioning

confidence: 96%

Keep moving and stay in a good shape to find your homologous recombination partner

Bordelet

Dubrana

2018

Curr Genet

View full text Add to dashboard Cite

Genomic DNA is constantly exposed to damage. Among the lesion in DNA, double-strand breaks (DSB), because they disrupt the two strands of the DNA double helix, are the more dangerous. DSB are repaired through two evolutionary conserved mechanisms: Non-Homologous End Joining (NHEJ) and Homologous Recombination (HR). Whereas NHEJ simply reseals the double helix with no or minimal processing, HR necessitates the formation of a 3′ssDNA through the processing of DSB ends by the resection machinery and relies on the recognition and pairing of this 3′ssDNA tails with an intact homologous sequence. Despite years of active research on HR, the manner by which the two homologous sequences find each other in the crowded nucleus, and how this modulates HR efficiency, only recently emerges. Here, we review recent advances in our understanding of the factors limiting the search of a homologous sequence during HR.

show abstract

Live cell microscopy analysis of radiation-induced DNA double-strand break motion

Cited by 163 publications

References 45 publications

Nanoscale histone localization in live cells reveals reduced chromatin mobility in response to DNA damage

Nanoscale histone localization in live cells reveals reduced chromatin mobility in response to DNA damage

Direct measurement of the 3-dimensional DNA lesion distribution induced by energetic charged particles in a mouse model tissue

Keep moving and stay in a good shape to find your homologous recombination partner

Contact Info

Product

Resources

About