85 research outputs found
Modulation of p53's transcriptional function by small molecules
p53 tumour suppressor is a transcriptional factor which induces apoptosis or growth arrest in response to stress thus eliminating damaged cells. p53 function is frequently abrogated in tumours either via inactivation mutations in the TP53 gene or by elevated activity of p53 negative regulators HDM2 and HDMX. Therefore application of small molecules that reactivate p53 function is a promising strategy for anti-cancer therapy. In addition, small molecules can serve as valuable research tool to study p53 biology.
This thesis is focused on the studies of p53 transcriptional response induced by small molecules and the molecular mechanisms contributing to the induction of apoptosis by p53. Using chromatin immunoprecipitation followed by deep sequencing (ChIP-seq) we compared genome-wide DNA binding profile of p53 activated by three different small molecules RITA, 5-FU and Nutlin-3a, causing various biological outcomes in breast carcinoma MCF7 cell line. We found that the major pattern of p53 binding to DNA does not depend on the mechanism of p53 activation or p53-induced cell fate. Surprisingly, we demonstrated that the majority of sites bound by p53 are located far away from transcription starting sites (TSS), thus making unclear their functional role. Comparison of p53 DNA binding sites in vicinity to TSS with changes in gene expression using microarray analysis revealed 280 novel p53 target genes. While the majority of p53 transactivated genes shared classical p53 consensus motif, we found it only in a few repressed genes, suggesting different mechanism of p53 transrepression. We validated several novel p53 target genes, including AURKA gene which is negatively regulated by p53. In addition, we showed that STAT3 transcription factor antagonizes p53-mediated regulation of several target genes, including AURKA. We demonstrated that the expression level of novel p53 target genes correlates with p53 status, tumour grade and survival in 265 breast cancer patients.
Investigation of molecular mechanisms of p53-mediated apoptosis upon RITA treatment revealed that in addition to activation of pro-apoptotic targets, p53 inhibited the expression of several crucial oncogenes. Thus, we showed that inhibition of several oncogenic and pro-survival factors, including c-Myc and Mcl-1, on mRNA and protein levels critically contributes to robust induction of apoptosis. We found that in contrast to p53-mediated transactivation, transrepression is more tightly regulated by HDM2 and depends on the ratio of p53 and HDM2 bound to gene promoters.
We found that RITA-activated p53 mediates a decrease in expression and protein stability of its negative regulator HDMX. Impaired stability of HDMX is caused by ATM-mediated phosphorylation of HDMX. In turn, the elevated activity of ATM correlates with depletion of p53 target gene Wip1 phosphatase that inhibits ATM. We demonstrated that the depletion of either HDMX or Wip1 enhances growth suppressive effects of p53-reactivating molecules RITA and Nutlin3a.
Our data showed that RITA inhibits glycolytic enzymes in p53-dependent manner. We found that p53 binds to DNA in vicinity from TSS of the metabolic genes and represses their transcription. Our data suggests that SP1 is a p53 transcriptional cofactor contributing to p53-mediated transrepression of several metabolic genes. Importantly, we showed that the block of glycolysis amplifies induction of apoptosis in cancer cells upon RITA treatment.
In conclusion, our data contribute to a deeper understanding of transcriptional response induced by p53, along with the identification of novel p53 target genes. Our studies revealed new targets of pharmacologically activated p53 which significantly increase the robustness of p53-mediated apoptosis
Cooperation Between Russia and China in the Field of Sports in 1992–2021
Российско-китайские
отношения в XX–XXI вв. являются предметом
исследования. Исследование российско-китайского
взаимодействия в разрезе
комплекса мероприятий в области спорта является центральным содержательным
направлением и предметом работы. Авторы ставят перед собой цель – исследовать
взаимовлияние двух государств через инструменты мягкой силы, определяющие
характер двусторонних отношений уровня «стратегическое партнерство». Одним
из результатов применения исторического метода в работе стала периодизация.
Роль данного метода очень важна, поскольку авторы исследовали материал
на достаточно длительном временном интервале, который составил 30 лет, что
позволило глубже понять ход двустороннего процесса международных отношений
в рамках исследуемого объема данных, а также упорядочить факты. Метод контент-анализа
позволил выявить содержание документов, принятых двумя странами.
В ходе анализа широкой источниковой базы был восстановлен весь постсоветский
период совместной политики в области спорта: события, факты, программы.
Ответственные служащие и их позиции в определении стратегических целей
спортивного сотрудничества также были установлены в данном исследовании.
В качестве результата работы была сопоставлена динамика различных процессов
в общей спортивной политике. Были проанализированы показатели в рамках
олимпийских достижений двух стран, правительственных встреч и на разном уровне
принятых документов. Ключевые направления спортивного сотрудничества были
систематизированы авторами в рамках таблицы по истории российско-китайской
подкомиссии по сотрудничеству в области спорта. Это может быть применимо
для стратегического планирования политики в области физкультуры и спорта двух
стран в рамках плана мероприятий по созданию условий для занятий физической
культурой и спортом в России и Китае. Выводом стало выявленное взаимное
укрепление сотрудничества по линии спорта с наращиванием товарооборота двух
странRussian-Chinese relations in the XX–XXI century. are the subject of research. The study of Russian-Chinese interaction in the context of a set of activities in the field of sports is the central content direction and subject of the work. The authors set themselves the goal of exploring the mutual influence of the two states through soft power tools that determine the nature of bilateral relations at the “strategic partnership” level. One of the results of applying the historical method in the work was periodization. The role of this method is very important, since the authors studied the material over a fairly long time interval, which was 30 years, which made it possible to better understand the course of the bilateral process of international relations within the framework of the studied data volume, as well as to streamline the facts. The content analysis method made it possible to reveal the content of the documents adopted by the two countries. In the course of the analysis of a wide source base, the entire post-Soviet period of a joint policy in the field of sports was restored: events, facts, programs. Responsible officials and their positions in determining the strategic goals of sports cooperation were also established in this study.
As a result of the work, the dynamics of various processes in the general sports policy was compared. The indicators were analyzed within the framework of the Olympic achievements of the two countries, government meetings and at various levels of adopted documents. The key areas of sports cooperation were systematized by the authors in the framework of the table on the history of the Russian-Chinese subcommittee on cooperation in the field of sports. This may be applicable for the strategic planning of the policy in the field of physical culture and sports of the two countries within the framework of the action plan to create conditions for physical culture and sports in Russia and China. The conclusion was the identified relationship between strengthening cooperation in the field of sports with increasing trade between the two countrie
Методика достижения стратегических целей на мезоуровне с помощью технологии имитационного моделирования
Under the conditions of transformational changes typical for the current stage of development of the Russian Federation economy, it becomes extremely important to conduct research on the development of tools in the field of strategic planning at the meso level.
The paper proposes a methodology for achieving strategic goals at the meso level. The methodology includes the principles and algorithm for achieving strategic goals. The principles expand the theoretical and methodological basis of planning in terms of achieving leading indicators in the strategic planning of the region. The algorithm of the methodology illustrates the relationship between leading indicators and the goals of strategic planning.
The paper may be useful to graduate students, scientists of higher educational institutions, state and municipal employees involved in strategic planning, as well as other interested partiesВ условиях трансформационных изменений, характерных для
современного этапа развития экономики Российской Федерации, чрезвычайно
актуальным становится проведение исследований, посвященных разработке
инструментов в области стратегического планирования на мезоуровне.
В статье предложена методика достижения стратегических целей на мезоуровне
с помощью технологии имитационного моделирования. Методика включает в себя
принципы и алгоритм достижения стратегических целей. Принципы расширяют
теоретическую и методологическую базу планирования в части достижения
опережающих показателей в стратегическом планировании региона. Алгоритм
методики иллюстрирует взаимосвязь опережающих показателей с целями
стратегического планирования.
Статья может быть полезна аспирантам, учёным высших учебных заведений,
государственным и муниципальным служащим, занимающимся стратегическим
планированием, а также иным заинтересованным лица
The State-of-the-Art of Set Visualization
Sets comprise a generic data model that has been used in a variety of data analysis problems. Such problems involve analysing and visualizing set relations between multiple sets defined over the same collection of elements. However, visualizing sets is a non-trivial problem due to the large number of possible relations between them. We provide a systematic overview of state-of-the-art techniques for visualizing different kinds of set relations. We classify these techniques into six main categories according to the visual representations they use and the tasks they support. We compare the categories to provide guidance for choosing an appropriate technique for a given problem. Finally, we identify challenges in this area that need further research and propose possible directions to address these challenges. Further resources on set visualization are available at http://www.setviz.net
IL-17A promotes intracellular growth of Mycobacterium by inhibiting apoptosis of infected macrophages
The fate of infected macrophages is a critical aspect of immunity to mycobacteria. By depriving the pathogen of its intracellular niche, apoptotic death of the infected macrophage has been shown to be an important mechanism to control bacterial growth. Here, we show that IL-17 inhibits apoptosis of Mycobacterium bovis BCG- or Mycobacterium tuberculosis-infected macrophages thus hampering their ability to control bacterial growth. Mechanistically, we show that IL-17 inhibits p53, and impacts on the intrinsic apoptotic pathway, by increasing the Bcl2 and decreasing Bax expression, decreasing cytochrome c release from the mitochondria, and inhibiting caspase-3 activation. The same effect of IL-17 was observed in infected macrophages upon blockade of p53 nuclear translocation. These results reveal a previously unappreciated role for the IL-17/p53 axis in the regulation of mycobacteria-induced apoptosis and can have important implications in a broad spectrum of diseases where apoptosis of the infected cell is an important host defense mechanism.Fundação para a Ciência e Tecnologia, Portugal. Project grants: PTDC/SAU-MII/101977/2008 (to AGC), PTDC/BIA-BCM/102776/2008 (to MS) and HMSP-ICT/0024/2010 (to RA) and co-funded by Programa Operacional Regional do Norte (ON.2 – O Novo Norte), Quadro de Referência Estratégico Nacional (QREN), through the Fundo Europeu de Desenvolvimento Regional (FEDER). Personal Grants: SFRH/BPD/33036/2006 to AC; SFRH/BD/33573/200
Forecast of radionuclide migration in groundwater of the zone affected by construction drainage at the Leningrad NPP-2
The distribution of natural (at the level of global background) and technogenic radionuclides in groundwater of the industrial zone in Sosnovy Bor town, where several nuclear power facilities are operating, was analyzed. The main technogenic radionuclides recorded in groundwater samples are cesium (137Cs), strontium (90Sr), and tritium isotopes. The first two aquifers from the surface are subject to contamination: the Quaternary and the upper zone of the Lomonosov aquifer. Based on extensive material on the engineering and geological studies of the work area, a 3D geological model and hydrodynamic and geomigration models of the industrial zone were constructed. By means of modeling, the extent and nature of changes in hydrogeological conditions of area resulting from the construction and operational drainage of the new stage of the Leningrad Nuclear Power Plant (LNPP-2) were determined. The “historical” halo of radioactive contamination of groundwater forming (1970-1990) at the site adjacent to the NPP, where the storage facility of low- and medium-level radioactive waste is located, falls into the zone of influence. Interpretation of monitoring data allowed obtaining the migration parameters for predictive estimates. Modeling has shown that during the time of the LNPP-2 operation there is was no intake of contaminated water by the drainage system of the new power plant
Deficiency and haploinsufficiency of histone macroH2A1.1 in mice recapitulate hematopoietic defects of human myelodysplastic syndrome
Background: Epigenetic regulation is important in hematopoiesis, but the involvement of histone variants is poorly understood. Myelodysplastic syndromes (MDS) are heterogeneous clonal hematopoietic stem cell (HSC) disorders characterized by ineffective hematopoiesis. MacroH2A1.1 is a histone H2A variant that negatively correlates with the self-renewal capacity of embryonic, adult, and cancer stem cells. MacroH2A1.1 is a target of the frequent U2AF1 S34F mutation in MDS. The role of macroH2A1.1 in hematopoiesis is unclear. Results: MacroH2A1.1 mRNA levels are significantly decreased in patients with low-risk MDS presenting with chromosomal 5q deletion and myeloid cytopenias and tend to be decreased in MDS patients carrying the U2AF1 S34F mutation. Using an innovative mouse allele lacking the macroH2A1.1 alternatively spliced exon, we investigated whether macroH2A1.1 regulates HSC homeostasis and differentiation. The lack of macroH2A1.1 decreased while macroH2A1.1 haploinsufficiency increased HSC frequency upon irradiation. Moreover, bone marrow transplantation experiments showed that both deficiency and haploinsufficiency of macroH2A1.1 resulted in enhanced HSC differentiation along the myeloid lineage. Finally, RNA-sequencing analysis implicated macroH2A1.1-mediated regulation of ribosomal gene expression in HSC homeostasis. Conclusions: Together, our findings suggest a new epigenetic process contributing to hematopoiesis regulation. By combining clinical data with a discrete mutant mouse model and in vitro studies of human and mouse cells, we identify macroH2A1.1 as a key player in the cellular and molecular features of MDS. These data justify the exploration of macroH2A1.1 and associated proteins as therapeutic targets in hematological malignancies
Growth arrest-specific transcript 5 associated snoRNA levels are related to p53 expression and DNA damage in colorectal cancer
BACKGROUND
The growth arrest-specific transcript 5 gene (GAS5) encodes a long noncoding RNA (lncRNA) and hosts a number of small nucleolar RNAs (snoRNAs) that have recently been implicated in multiple cellular processes and cancer. Here, we investigate the relationship between DNA damage, p53, and the GAS5 snoRNAs to gain further insight into the potential role of this locus in cell survival and oncogenesis both in vivo and in vitro.
METHODS
We used quantitative techniques to analyse the effect of DNA damage on GAS5 snoRNA expression and to assess the relationship between p53 and the GAS5 snoRNAs in cancer cell lines and in normal, pre-malignant, and malignant human colorectal tissue and used biological techniques to suggest potential roles for these snoRNAs in the DNA damage response.
RESULTS
GAS5-derived snoRNA expression was induced by DNA damage in a p53-dependent manner in colorectal cancer cell lines and their levels were not affected by DICER. Furthermore, p53 levels strongly correlated with GAS5-derived snoRNA expression in colorectal tissue.
CONCLUSIONS
In aggregate, these data suggest that the GAS5-derived snoRNAs are under control of p53 and that they have an important role in mediating the p53 response to DNA damage, which may not relate to their function in the ribosome. We suggest that these snoRNAs are not processed by DICER to form smaller snoRNA-derived RNAs with microRNA (miRNA)-like functions, but their precise role requires further evaluation. Furthermore, since GAS5 host snoRNAs are often used as endogenous controls in qPCR quantifications we show that their use as housekeeping genes in DNA damage experiments can lead to inaccurate results
ПРОБЛЕМЫ КЛАССИФИКАЦИИ ОБЪЕКТОВ ГОСТИНИЧНОЙ ИНДУСТРИИ В КРЫМУ: ПРАВОВЫЕ АСПЕКТЫ
The article analyzes the legal aspects of classification of hotels and other accommodation facilities on the territory of the Republic of Crimea, the problems that arise during this process, the actual situation of hotels and other accommodation facilities in Crimea at the present time. The necessity of regulating the legislative acts of the Republic of Crimea in terms of the issue under study is justified.В статье анализируются правовые аспекты классификации гостиниц и иных средств размещения на территории Республики Крым, проблемы, возникающие в ходе этого процесса, фактическое положение гостиниц и иных средств размещения Крыма в настоящее время. Обосновывается необходимость регулирования законодательных актов Республики Крым в части исследуемого вопроса
- …