Maintenance and Function of a Plant Chromosome in Human Cells

Пространственная организация хроматина важна для нормального функционирования клетки. На архитектуру ядра влияют размеры отдельных фрагментов генома, которые коррелируют с числом копий этих фрагментов. Перемещение локусов 1q12 от поверхности ядра в центральные области является ключевой стадией адаптивного ответа клетки на стресс. Мы предположили, что размер локусов 1q12, который коррелирует с содержанием повтора f-SatIII, может влиять на перемещение этих участков хроматина в ядре. Методом FISH на выделенных лимфоцитах показали, что в контроле локусы 1q12 расположены вблизи поверхности ядра, в ядрах лимфоцитов больных шизофренией (БШ) и облученных контрольных клеток локусы 1q12 расположены в центральных районах ядра. Длительное культивирование облученных лимфоцитов сопровождалось гибелью клеток, и снижением содержания f-SatIII в ДНК. Очевидно, что погибали клетки с большим размером 1q12 (много f-SatIII), обогащая популяцию клетками с низким содержанием f-SatIII. В клетках БШ и в облученных клетках мы обнаружили повышение уровня РНК SATIII. Размеры гетерохроматина 1q12 в клетках человека могут влиять на процессы пролиферации и ответа клетки на стресс. Количественный полиморфизм тандемных повторов генома - один из эпигенетических механизмов регуляции ответа клеток на окислительный стресс. The spatial organization of chromatin is important for the normal functioning of the cell. Genome repeat cluster sizes can affect the chromatin spatial configuration and function. The 1q12 heterochromatin loci movement from the periphery to the center of the nucleus is the cells’ universal response to various types of stress. We hypothesized that a large 1q12 domain could affect chromatin movement, thereby inhibiting adaptive response (AR). Using the FISH method, we shown that in the control, 1q12 loci are located near the surface of the nucleus; in the lymphocyte nuclei of schizophrenic patients and irradiated control cells, 1q12 loci are located in the central regions of the nucleus. During prolonged cultivation, the irradiated cells with a large Large f-SatIII amount die and the population is enriched with the cells with low f-SatIII content. In intact SZ patients’ lymphocytes and in irradiated cells we found an increase in SATIII RNA levels. The size of heterochromatin 1q12 loci in human cells can affect to the proliferation and cells’ adaptive response to stress. Quantitative polymorphism of tandem genome repeats is one of the epigenetic mechanisms of genome expression’s regulation.

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ppGpp functions as an alarmone in metazoa

10.1101/2019.12.16.878942 ◽

2019 ◽

Author(s):

Doshun Ito ◽

Hinata Kawamura ◽

Akira Oikawa ◽

Yuta Ihara ◽

Toshio Shibata ◽

...

Keyword(s):

Cell Death ◽

Drosophila Melanogaster ◽

Environmental Changes ◽

Nutrient Deficiency ◽

Stringent Response ◽

Human Cells ◽

Metabolic Changes ◽

Animal Cells ◽

Physiological Relevance ◽

And Function

AbstractGuanosine 3’,5’-bis(pyrophosphate) (ppGpp) functions as a second messenger in bacteria to adjust their physiology in response to environmental changes. In recent years, the ppGpp-specific hydrolase, metazoan SpoT homolog-1 (Mesh1), was shown to have important roles for growth under nutrient deficiency in Drosophila melanogaster. Curiously, however, ppGpp has never been detected in animal cells, and therefore the physiological relevance of this molecule, if any, in metazoans has not been established. Here, we report the detection of ppGpp in Drosophila and human cells and demonstrate that ppGpp accumulation induces metabolic changes, cell death, and eventually lethality in Drosophila. Our results provide the first evidence of the existence and function of the ppGpp-dependent stringent response in animals.

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Cooperation of the NEIL3 and Fanconi anemia/BRCA pathways in interstrand crosslink repair

Nucleic Acids Research ◽

10.1093/nar/gkaa038 ◽

2020 ◽

Vol 48 (6) ◽

pp. 3014-3028 ◽

Cited By ~ 10

Author(s):

Niu Li ◽

Jian Wang ◽

Susan S Wallace ◽

Jing Chen ◽

Jia Zhou ◽

...

Keyword(s):

Fanconi Anemia ◽

Excision Repair ◽

Human Cells ◽

Dependent Manner ◽

Major Pathway ◽

Interstrand Crosslinks ◽

Interstrand Crosslink ◽

Pathway Activation ◽

Base Excision ◽

And Function

Abstract The NEIL3 DNA glycosylase is a base excision repair enzyme that excises bulky base lesions from DNA. Although NEIL3 has been shown to unhook interstrand crosslinks (ICL) in Xenopus extracts, how NEIL3 participants in ICL repair in human cells and its corporation with the canonical Fanconi anemia (FA)/BRCA pathway remain unclear. Here we show that the NEIL3 and the FA/BRCA pathways are non-epistatic in psoralen-ICL repair. The NEIL3 pathway is the major pathway for repairing psoralen-ICL, and the FA/BRCA pathway is only activated when NEIL3 is not present. Mechanistically, NEIL3 is recruited to psoralen-ICL in a rapid, PARP-dependent manner. Importantly, the NEIL3 pathway repairs psoralen-ICLs without generating double-strand breaks (DSBs), unlike the FA/BRCA pathway. In addition, we found that the RUVBL1/2 complex physically interact with NEIL3 and function within the NEIL3 pathway in psoralen-ICL repair. Moreover, TRAIP is important for the recruitment of NEIL3 but not FANCD2, and knockdown of TRAIP promotes FA/BRCA pathway activation. Interestingly, TRAIP is non-epistatic with both NEIL3 and FA pathways in psoralen-ICL repair, suggesting that TRAIP may function upstream of the two pathways. Taken together, the NEIL3 pathway is the major pathway to repair psoralen-ICL through a unique DSB-free mechanism in human cells.

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Pharmacological characterisation of small molecule C5aR1 inhibitors in human cells reveals biased activities for signalling and function

Biochemical Pharmacology ◽

10.1016/j.bcp.2020.114156 ◽

2020 ◽

Vol 180 ◽

pp. 114156 ◽

Cited By ~ 4

Author(s):

Xaria X. Li ◽

John D. Lee ◽

Nicholas L. Massey ◽

Carolyn Guan ◽

Avril A.B. Robertson ◽

...

Keyword(s):

Small Molecule ◽

Human Cells ◽

And Function

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Regulation and Function of RNA Pseudouridylation in Human Cells

Annual Review of Genetics ◽

10.1146/annurev-genet-112618-043830 ◽

2020 ◽

Vol 54 (1) ◽

pp. 309-336

Author(s):

Erin K. Borchardt ◽

Nicole M. Martinez ◽

Wendy V. Gilbert

Keyword(s):

Messenger Rna ◽

Noncoding Rna ◽

Protein Production ◽

Rna Binding ◽

Rna Binding Proteins ◽

Human Cells ◽

Rna Sequences ◽

Rna Targets ◽

Pseudouridine Synthases ◽

And Function

Recent advances in pseudouridine detection reveal a complex pseudouridine landscape that includes messenger RNA and diverse classes of noncoding RNA in human cells. The known molecular functions of pseudouridine, which include stabilizing RNA conformations and destabilizing interactions with varied RNA-binding proteins, suggest that RNA pseudouridylation could have widespread effects on RNA metabolism and gene expression. Here, we emphasize how much remains to be learned about the RNA targets of human pseudouridine synthases, their basis for recognizing distinct RNA sequences, and the mechanisms responsible for regulated RNA pseudouridylation. We also examine the roles of noncoding RNA pseudouridylation in splicing and translation and point out the potential effects of mRNA pseudouridylation on protein production, including in the context of therapeutic mRNAs.

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Progress in artificial chromosome technology

Biochemical Society Transactions ◽

10.1042/bst0340324 ◽

2006 ◽

Vol 34 (2) ◽

pp. 324-327 ◽

Cited By ~ 14

Author(s):

Z. Larin Monaco ◽

D. Moralli

Keyword(s):

Mammalian Cells ◽

Artificial Chromosome ◽

Regulatory Elements ◽

Human Cells ◽

Artificial Chromosomes ◽

Expression Studies ◽

Excellent Research ◽

Somatic Gene ◽

Transfer Vectors ◽

And Function

Artificial chromosomes is an exciting technology which has developed rapidly since the late 1990s. HACs (human artificial chromosomes) are autonomous molecules that can function and segregate as normal chromosomes in human cells. The advantages of an artificial-chromosome-based system are 2-fold. First, HACs are an excellent research tool for investigating the requirements for normal chromosome structure and function during the cell cycle. They are important in defining the sequence requirements of functional chromosomes, and investigating the organization and composition of the chromatin. Secondly, HACs are useful gene-transfer vectors for expression studies in mammalian cells, with the capacity to incorporate large DNA segments encompassing genes and their regulatory elements. As episomes, they are stably maintained, leading to more reliable and prolonged transgene expression. HACs offer the possibility of long-term gene expression in human cells and the development of future somatic gene therapy.

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THE PRESERVATION OF LIVING RED BLOOD CELLS IN VITRO

Journal of Experimental Medicine ◽

10.1084/jem.23.2.239 ◽

1916 ◽

Vol 23 (2) ◽

pp. 239-248 ◽

Cited By ~ 45

Author(s):

Peyton Rous ◽

J. R. Turner

Keyword(s):

Red Blood Cells ◽

Blood Cells ◽

Large Scale ◽

Blood Count ◽

Sodium Citrate ◽

Human Cells ◽

Red Cells ◽

Long Time ◽

And Function

In order to determine the availability for functional uses of red cells kept in vitro by our methods, transfusion experiments have been carried out with rabbits by which a large part of their blood was replaced with kept rabbit cells suspended in Locke's solution. It has been found that erythrocytes preserved in mixtures of blood, sodium citrate, saccharose, and water for 14 days, and used to replace normal blood, will remain in circulation and function so well that the animal shows no disturbance, and the blood count, hemoglobin, and percentage of reticulated red cells remain unvaried. Cells kept for longer periods, though intact and apparently unchanged when transfused, soon leave the circulation. Animals in which this disappearance of cells is taking place on a large scale, remain healthy save for the progressing anemia. The experiments prove that, in the exsanguinated rabbit at least, transfusions of cells kept for a long time in vitro may be used to replace the blood lost, and that when the cells have been kept too long but are still intact they are disposed of without harm. The indications are that kept human cells could be profitably employed in the same way.

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CD8+ Regulatory T Cells, and Not CD4+ T Cells, Dominate Suppressive Phenotype and Function after In Vitro Live Mycobacterium bovis-BCG Activation of Human Cells

PLoS ONE ◽

10.1371/journal.pone.0094192 ◽

2014 ◽

Vol 9 (4) ◽

pp. e94192 ◽

Cited By ~ 25

Author(s):

Mardi C. Boer ◽

Krista E. van Meijgaarden ◽

Simone A. Joosten ◽

Tom H. M. Ottenhoff

Keyword(s):

T Cells ◽

Regulatory T Cells ◽

Mycobacterium Bovis ◽

Cd4 T Cells ◽

Human Cells ◽

Mycobacterium Bovis Bcg ◽

Suppressive Phenotype ◽

And Function

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Cohesion promotes nucleolar structure and function

Molecular Biology of the Cell ◽

10.1091/mbc.e13-07-0377 ◽

2014 ◽

Vol 25 (3) ◽

pp. 337-346 ◽

Cited By ~ 29

Author(s):

Bethany Harris ◽

Tania Bose ◽

Kenneth K. Lee ◽

Fei Wang ◽

Shuai Lu ◽

...

Keyword(s):

Ribosome Biogenesis ◽

Molecular Mechanisms ◽

Human Cells ◽

Rna Polymerase I ◽

Nucleolar Structure ◽

Roberts Syndrome ◽

Evolutionarily Conserved ◽

Rrna Cleavage ◽

And Function ◽

Polymerase I

The cohesin complex contributes to ribosome function, although the molecular mechanisms involved are unclear. Compromised cohesin function is associated with a class of diseases known as cohesinopathies. One cohesinopathy, Roberts syndrome (RBS), occurs when a mutation reduces acetylation of the cohesin Smc3 subunit. Mutation of the cohesin acetyltransferase is associated with impaired rRNA production, ribosome biogenesis, and protein synthesis in yeast and human cells. Cohesin binding to the ribosomal DNA (rDNA) is evolutionarily conserved from bacteria to human cells. We report that the RBS mutation in yeast (eco1-W216G) exhibits a disorganized nucleolus and reduced looping at the rDNA. RNA polymerase I occupancy of the genes remains normal, suggesting that recruitment is not impaired. Impaired rRNA production in the RBS mutant coincides with slower rRNA cleavage. In addition to the RBS mutation, mutations in any subunit of the cohesin ring are associated with defects in ribosome biogenesis. Depletion or artificial destruction of cohesion in a single cell cycle is associated with loss of nucleolar integrity, demonstrating that the defects at the rDNA can be directly attributed to loss of cohesion. Our results strongly suggest that organization of the rDNA provided by cohesion is critical for formation and function of the nucleolus.

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