scholarly journals DNA-RNA Hybrid (R-Loop): From a Unified Picture of the Mammalian Telomere to the Genome-Wide Profile

Cells ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 1556
Author(s):  
Minoo Rassoulzadegan ◽  
Ali Sharifi-Zarchi ◽  
Leila Kianmehr

Local three-stranded DNA/RNA hybrid regions of genomes (R-loops) have been detected either by binding of a monoclonal antibody (DRIP assay) or by enzymatic recognition by RNaseH. Such a structure has been postulated for mouse and human telomeres, clearly suggested by the identification of the complementary RNA Telomeric repeat-containing RNA “TERRA”. However, the tremendous disparity in the information obtained with antibody-based technology drove us to investigate a new strategy. Based on the observation that DNA/RNA hybrids in a triplex complex genome co-purify with the double-stranded chromosomal DNA fraction, we developed a direct preparative approach from total protein-free cellular extract without antibody that allows their physical isolation and determination of their RNA nucleotide sequence. We then define in the normal mouse and human sperm genomes the notion of stable DNA associated RNA terminal R-loop complexes, including TERRA molecules synthesized from local promoters of every chromosome. Furthermore, the first strong evidence of all telomeric structures, applied additionally to the whole murine sperm genome compared to the testes, showed reproducible R-loop complexes of the whole genome and suggesting a defined profile in the sperm genome for the next generation.

2020 ◽  
Author(s):  
Minoo Rassoulzadegan ◽  
Ali Sharifi-Zarchi ◽  
Leila Kianmehr

SummaryLocal three-stranded DNA-RNA hybrid regions of the genomes (R-loops) have been detected either by binding of a monoclonal antibody (DRIP assay) or by enzymatic recognition by RNaseH. Such a structure has been postulated for the mouse and human telomeres, clearly suggested by the identification of the complementary RNA TERRA. It was, however, evidenced by DRIP exclusively in human cancer and not in normal human nor in any mouse cell. Based on the observation that in several fractionation procedures, DNA-RNA hybrids copurify with double-stranded DNA, we developed a preparative approach that allows detection of stable DNA-RNA triplexes in a complex genome, their physical isolation and their RNA nucleotide sequence. We then define in the normal mouse and human genomes the notion of terminal R-loop complexes including TERRA molecules synthesized from local promoters of every chromosome. In addition to the telomeric structures since, the finding of the RNA peak, applied in addition to the whole murine sperm genomes, has highlighted a reproducible profile of the R-loop complexes from entire genome suggesting a defined profile for a future generation.


Talanta ◽  
2012 ◽  
Vol 93 ◽  
pp. 212-218 ◽  
Author(s):  
Rivelino M. Cavalcante ◽  
Danielle M. Lima ◽  
Gabrielle M. Fernandes ◽  
Wersângela C. Duaví

The Nucleus ◽  
2011 ◽  
Vol 54 (2) ◽  
pp. 71-75
Author(s):  
V. Rao Bandaru ◽  
Tavva S. S. Mohan Dev ◽  
P. V. Arjuna Rao ◽  
M. V. Subba Rao

Vestnik ◽  
2021 ◽  
pp. 226-232
Author(s):  
К. К. Тлеуханов ◽  
Н. А. Алтыбаева ◽  
М. К. Отарбаев ◽  
Е. М. Тойшибеков ◽  
А. А. Тлеуханова

В статье представлены собранные данные о методах устранения повышенной частоты фрагментации ДНК у сперматозоидов, которые в некоторых исследованиях подтверждают, что введение антиоксидантов может снизить уровень фрагментации ДНК у сперматозоидов. The article presents collected data on methods of eliminating the increased frequency of DNA fragmentation in spermatozoa, which in some studies confirm that the introduction of antioxidants can reduce the level of DNA fragmentation in spermatozoa.


PLoS ONE ◽  
2017 ◽  
Vol 12 (1) ◽  
pp. e0171088 ◽  
Author(s):  
George Msalya ◽  
Eui-Soo Kim ◽  
Emmanuel L. K. Laisser ◽  
Maulilio J. Kipanyula ◽  
Esron D. Karimuribo ◽  
...  

2019 ◽  
Vol 14 (4) ◽  
pp. 20-23
Author(s):  
M. M. Vasilyeva ◽  
I. P. Moshurov ◽  
L. Yu. Grivtsova ◽  
N. N. Tupitsyn ◽  
N. A. Kozlov ◽  
...  

Background. A new strategy of breast cancer management is required for effective disease prevention and control. Immunotherapy is one of promising options.Objective: to evaluate the effect of immunoadjuvant polyoxidonium on pathmorphological changes in breast tumors.Materials and methods. The study was performed in 75 patients with breast cancer: 50 patients received polyoxidonium in a neoadjuvant regimen (main group), 25 patients did not receive polyoxidonium (control group). Polyoxidonium at a dose of 12 mg was administered intramuscularly 1 time per day on the days 1, 2, 3, 5 and 7 before surgery; on the day 8, radical mastectomy was performed in patients of both groups, followed by histological examination and determination of the grade of therapeutic pathomorphosis of the tumor.Results. The proportion of cases with grade I therapeutic pathomorphosis was 58 %, grade II therapeutic pathomorphosis – 6 %. Pathomorphosis in metastatic lymph nodes was observed in 22.7 % of cases.Conclusion. The anti-tumor effect of polyoxidonium was confirmed on the basis of the induction of pathomorphosis of the tumor tissue of breast cancer.


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