scholarly journals Characterizing the DNA Damage Response by Cell Tracking Algorithms and Cell Features Classification Using High-Content Time-Lapse Analysis

PLoS ONE ◽  
2015 ◽  
Vol 10 (6) ◽  
pp. e0129438 ◽  
Author(s):  
Walter Georgescu ◽  
Alma Osseiran ◽  
Maria Rojec ◽  
Yueyong Liu ◽  
Maxime Bombrun ◽  
...  
2021 ◽  
Vol 7 (3) ◽  
pp. eabe3882
Author(s):  
Jenny F. Nathans ◽  
James A. Cornwell ◽  
Marwa M. Afifi ◽  
Debasish Paul ◽  
Steven D. Cappell

The G1-S checkpoint is thought to prevent cells with damaged DNA from entering S phase and replicating their DNA and efficiently arrests cells at the G1-S transition. Here, using time-lapse imaging and single-cell tracking, we instead find that DNA damage leads to highly variable and divergent fate outcomes. Contrary to the textbook model that cells arrest at the G1-S transition, cells triggering the DNA damage checkpoint in G1 phase route back to quiescence, and this cellular rerouting can be initiated at any point in G1 phase. Furthermore, we find that most of the cells receiving damage in G1 phase actually fail to arrest and proceed through the G1-S transition due to persistent cyclin-dependent kinase (CDK) activity in the interval between DNA damage and induction of the CDK inhibitor p21. These observations necessitate a revised model of DNA damage response in G1 phase and indicate that cells have a G1 checkpoint.


2020 ◽  
Vol 10 (9) ◽  
pp. 2981-2988
Author(s):  
Erica Silva ◽  
Manuel Michaca ◽  
Brenton Munson ◽  
Gordon J Bean ◽  
Philipp A Jaeger ◽  
...  

Abstract Genetic screens in Saccharomyces cerevisiae have allowed for the identification of many genes as sensors or effectors of DNA damage, typically by comparing the fitness of genetic mutants in the presence or absence of DNA-damaging treatments. However, these static screens overlook the dynamic nature of DNA damage response pathways, missing time-dependent or transient effects. Here, we examine gene dependencies in the dynamic response to ultraviolet radiation-induced DNA damage by integrating ultra-high-density arrays of 6144 diploid gene deletion mutants with high-frequency time-lapse imaging. We identify 494 ultraviolet radiation response genes which, in addition to recovering molecular pathways and protein complexes previously annotated to DNA damage repair, include components of the CCR4-NOT complex, tRNA wobble modification, autophagy, and, most unexpectedly, 153 nuclear-encoded mitochondrial genes. Notably, mitochondria-deficient strains present time-dependent insensitivity to ultraviolet radiation, posing impaired mitochondrial function as a protective factor in the ultraviolet radiation response.


2021 ◽  
Author(s):  
Pin-Rui Su ◽  
Li You ◽  
Cecile Beerens ◽  
Karel Bezstarosti ◽  
Jeroen Demmers ◽  
...  

Tumor heterogeneity is an important source of cancer therapy resistance. Single cell proteomics has the potential to decipher protein content leading to heterogeneous cellular phenotypes. Single-Cell ProtEomics by Mass Spectrometry (SCoPE-MS) is a recently developed, promising, unbiased proteomic profiling techniques, which allows profiling several tens of single cells for >1000 proteins per cell. However, a method to link single cell proteomes with cellular behaviors is needed to advance this type of profiling technique. Here, we developed a microscopy-based functional single cell proteomic profiling technology, called FUNpro, to link the proteome of individual cells with phenotypes of interest, even if the phenotypes are dynamic or the cells of interest are sparse. FUNpro enables one i) to screen thousands of cells with subcellular resolution and monitor (intra)cellular dynamics using a custom-built microscope, ii) to real-time analyze (intra)cellular dynamics of individual cells using an integrated cell tracking algorithm, iii) to promptly isolate the cells displaying phenotypes of interest, and iv) to single cell proteomically profile the isolated cells. We applied FUNpro to proteomically profile a newly identified small subpopulation of U2OS osteosarcoma cells displaying an abnormal, prolonged DNA damage response (DDR) after ionizing radiation (IR). With this, we identified PDS5A and PGAM5 proteins contributing to the abnormal DDR dynamics and helping the cells survive after IR.


2020 ◽  
Author(s):  
Erika Shor ◽  
Rocio Garcia-Rubio ◽  
Lucius DeGregorio ◽  
David S. Perlin

ABSTRACTTo protect genome integrity, eukaryotic cells respond to DNA damage by triggering highly conserved checkpoint mechanisms involving the phosphorylation of Rad53/CHK2 kinase. Budding yeast Candida glabrata, closely related to model eukaryote Saccharomyces cerevisiae, is an opportunistic pathogen characterized by high genetic diversity and rapid emergence of drug resistant mutants. However, the mechanisms enabling this genetic variability are unclear. Here we show that C. glabrata cells exposed to DNA damage neither induce CgRad53 phosphorylation nor accumulate in S phase, and exhibit higher lethality than S. cerevisiae. Furthermore, time-lapse microscopy showed C. glabrata cells continuing to divide in the presence of DNA damage, resulting in mitotic errors and cell death. Finally, RNAseq analysis revealed transcriptional rewiring of the DNA damage response in C. glabrata and identified several key protectors of genome stability upregulated by DNA damage in S. cerevisiae but downregulated in C. glabrata, including PCNA. Together, our results reveal a non-canonical fungal DNA damage response, which may contribute to rapidly generating genetic change and drug resistance.


Diabetes ◽  
2020 ◽  
Vol 69 (Supplement 1) ◽  
pp. 2118-P
Author(s):  
CHAY TENG YEO ◽  
BRYNDON OLESON ◽  
JOHN A. CORBETT ◽  
JAMIE K. SCHNUCK

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