Centromere and Pericentromere Transcription: Roles and Regulation … in Sickness and in Health

The chromosomal loci known as centromeres (CEN) mediate the equal distribution of the duplicated genome between both daughter cells. Specifically, centromeres recruit a protein complex named the kinetochore, that bi-orients the replicated chromosome pairs to the mitotic or meiotic spindle structure. The paired chromosomes are then separated, and the individual chromosomes segregate in opposite direction along the regressing spindle into each daughter cell. Erroneous kinetochore assembly or activity produces aneuploid cells that contain an abnormal number of chromosomes. Aneuploidy may incite cell death, developmental defects (including genetic syndromes), and cancer (>90% of all cancer cells are aneuploid). While kinetochores and their activities have been preserved through evolution, the CEN DNA sequences have not. Hence, to be recognized as sites for kinetochore assembly, CEN display conserved structural themes. In addition, CEN nucleosomes enclose a CEN-exclusive variant of histone H3, named CENP-A, and carry distinct epigenetic labels on CENP-A and the other CEN histone proteins. Through the cell cycle, CEN are transcribed into non-coding RNAs. After subsequent processing, they become key components of the CEN chromatin by marking the CEN locus and by stably anchoring the CEN-binding kinetochore proteins. CEN transcription is tightly regulated, of low intensity, and essential for differentiation and development. Under- or overexpression of CEN transcripts, as documented for myriad cancers, provoke chromosome missegregation and aneuploidy. CEN are genetically stable and fully competent only when they are insulated from the surrounding, pericentromeric chromatin, which must be silenced. We will review CEN transcription and its contribution to faithful kinetochore function. We will further discuss how pericentromeric chromatin is silenced by RNA processing and transcriptionally repressive chromatin marks. We will report on the transcriptional misregulation of (peri)centromeres during stress, natural aging, and disease and reflect on whether their transcripts can serve as future diagnostic tools and anti-cancer targets in the clinic

Altered hypothalamic-pituitary-adrenal axis activity in patients with chronic heart failure

In our study we applied immunohistochemical method and quantitative analysis to investigate an expression of hypothalamic neurohormones (corticotropin-releasing hormone, vasopressin) and adrenocorticotropin hormone in the pituitary, as well as performed general histological examination of the adrenal contexyesBelgorod State Universit

Влияние препарата Мицефит на семенную продуктивность и качество гибридных семян кабачка (Cucurbita pepo var. giramontia Duch.)

Relevance. Biologically active compounds are widely used at the modern vegetable production, and especially at the seed production. Influence of Micephyt preparation in the mixed with Etrel is evaluated at the first time. The goal of the study is evaluation the effect of Micephyt in the mixed of Etrel on the obtaining of hybrid seeds of the squash (Cucurbita pepo var. giramontia Duch.).Materials and methods. Studies were carried out at the experimental plot Transnistrian State University named T.G. Shevchenko (Tiraspol) during 2010-2012. The object of studies was maternal line F1 (166/5x98/5) of squash (analog of commercial hybrid F1 Lenutsa). Materials of study were preparations: Etrel (c= 0 and 300 ppm) and Micephyt in the mixed with Etrel (c= 10 and 100 ppm). There were 2 treatments of squash plants with these preparations: at the stage 2-3 leaves, and at the stage of 6-7 leaves.Results. Treatments maternal line of squash F1 with mixed preparation “Etrel-300 ppm + Micephyt-10 ppm” show the positive effect on the seed productivity of plants. We observed the significant increasing main components of seed productivity during three years of study. The mass of 1000 seed was increased on 10.1%; the quantity of seed fruits was increased on 9.0%; the quantity of fruits on the plant was increased on 11.8% and the seed productivity was increased on 33.0%. Seed yields of F1 squash were increased in 1.37 times on the standard (“Etrel-300 ppm”) after plant treatment with mixed preparation “Etrel-300 ppm + Micephyt-10 ppm”. High quality of seeds was maintained. The profitability of additional costs associated with the use of the preparation Micephit for the treatment of the maternal line 166/5 squash was 343%. So, the treatment of squash plants with mixed preparation “Etrel-300 ppm + Micephyt-10 ppm” is economic effective element the technology of F1 squash hybrid seed production.Актуальность. Биологически активные препараты широко используются в современном овощеводстве, и, в частности, в семеноводстве овощных культур. Изучение влияния препарата Мицефит (в смеси с препаратом Этрел) на семенную продуктивность и качество гибридных семян кабачка проводится впервые. Цель исследований – оценить эффективность совместного применения препаратов Мицефит и Этрел при выращивании гибридных семян кабачка.Материалы и методы. Исследования проводили на экспериментальном участке Приднестровского государственного университета им. Т.Г. Шевченко (г. Тирасполь) в 2010-2012 годах. Объект исследований – материнская линия гибрида F1 (166/5x98/5) кабачка (аналог коммерческого гибрида F1 Ленуца). Материалы исследования: препараты Этрел, концентрации -0 и 300 мг/л; Мицефит в баковой смеси с Этрелом, концентрации 10 мг/л и 100 мг/л. Препарат и смеси препаратов использовали для обработки материнской линии кабачка в фазы 2-3 и 6-7 настоящих листьев путём опрыскивания.Результаты. Обработки материнской линии гибрида F1 (166/5x98/5) кабачка баковой смесью Этрел – 300 мг/л + Мицефит – 10 мг/л оказали положительное воздействие на компоненты семенной продуктивности растений. В среднем за три года существенно увеличились: масса 1000 семян – на 10,1%, осемененность плодов – на 9,0%, количество семенников на растении – на 11,8%, семенная продуктивность – на 33,0%. Урожайность семян гибрида кабачка при обработке баковой смесью препаратами Этрел и Мицефит была в 1,37 раза выше стандарта –Этрел – 300 мг/л при сохранении высоких посевных качеств семян.  Рентабельность дополнительных затрат, связанных с применением препарата Мицефит для обработки материнской линии 166/5 кабачка, составила 343%. Использование препарата Мицефит как элемента технологии выращивания гибридных семян кабачка экономически выгодно

Особенности размерной поливариантности семян Cucurbita pepo var. giramontia Duch. в условиях изменения климата в Приднестровье

Actuality. Industrial technologies of vegetable crops cultivation, including squash cultivation, a lot of attention is paid to the uniformity of seeds by morphometric traits as a condition allowing to use the precision technologies.The goal of the study is to determine specificities of measured polyvariance the seeds of Cucurbita pepo var. giramontia Duch. under changes of climate conditions in Transnistria.Materials and methods. The studies were carried out at the experimental plot of Pridnestrovian State University (Tiraspol) in 2005-2012. Objects of studies – 5 lines (166/5; 19/84; 98/5; 5Б; 48/20) of squash. Morphometric traits of seeds: mass, width, length, thickness were evaluated in the sample of 100 seeds. Mass of the seed was evaluated with help of torsion scales with exactness to 0,001 g. Width, length, thickness were mesuared with microscope MBS-10 with exactness to 0,1 mm. squash plants were treated with water solutions of the preperation Micefit in concentrations 10 and 100 mg/l in the phase of "2-3 true leaves" and "6-7 true leaves", standard is water treatment.Meteorological conditions (temperature, amount of precipitation) the year of seed reproduction were characterized by the data of Tiraspol Agrometeorological Station. Hydrothermal regime the growing of squash plants was characterized by the hydrothermal coefficient (CHT) of Selyaninov.Results. The nature of changes in temperature and precipitation over 7 years (2005-2012 periods) were reflected increased anomality of weather conditions in Transnistrian region. First of all, it concerns the quantity and the intensity of precipitation during the formation and maturation of squash seeds. Distribution decades of total precipitation and temperatures caused extremely uneven hydration: CHT variation ratio was 29.2-61.3%. Almost all periods of study were stressful for plants and led to the dimensional polyvariance of squash seeds. The variation of morphometric traits (coefficient of variation) is depended on changes in the hydrothermal regime of the growing season. It has a non-linear character and was genotypically caused. Applying the preparation Micefit had a significant effect on the manifestation of traits of squash seeds and its interaction with meteorological factors determined their modifying ability in the following order: mass (78,2%)→ length (56,6%)→ thickness (43,7%)→ width (40,4%).Актуальность: В промышленных технологиях возделывания овощных культур, в том числе кабачка овощного, большое внимание уделяется выравненности семян по морфометрическим признакам как условию, позволяющему перейти на прецизионные технологии. Размерная поливариантность семян является атрибутом, границы которого определяются комплексом экологических факторов.Цель исследований – определить особенности размерной поливариантности семян Сucurbita pepo var. giramontia Duch. в условиях изменения климата в Приднестровье.Материалы и методы. Исследования проводили на экспериментальном участке Приднестровского государственного университета им. Т.Г. Шевченко ( г. Тирасполь) в 2005-2012 годах. Объект исследований – 5 линий (166/5; 19/84; 98/5; 5Б; 48/20) кабачка овощного. Морфометрические признаки семян учитывали в лабораторных условиях в выборке объёмом 100 шт. Взвешивали каждое семя на торсионных весах ВТ-500 с точностью до 0,001 г и измеряли каждое семя в отдельности, определяя длину (l), ширину (w) и толщину (t) с использованием микроскопа МБС-10 с точностью до 0,1 мм. Растения кабачка обрабатывали водными растворами препарата Мицефит в концентрации 10 и 100 мг/л в фазу 2-3 настоящих листьев и 6-7 листьев, контроль – обработка водой. Метеорологические условия (температура, сумма осадков) года репродукции семян кабачка характеризовали по данным Тираспольской агрометеорологической станции. Гидротермический режим периода вегетации растений кабачка определяли по гидротермическому коэффициенту (ГТК) Селянинова.Результаты. Характер изменений температуры воздуха и осадков в течение 7 лет (2005-2012 годы) показал возросшую аномальность погодных условий в Приднестровье. Характер распределения декадных суммарных осадков и температур обусловил крайне неравномерное увлажнение: коэффициенты вариации ГТК составляли 29,2-61,3%. Периоды со стрессовыми условиями для растений проявлялись на протяжении всего времени наблюдения. Это обусловило размерную поливариантность семян кабачка овощного. Варьирование морфометрических признаков семян (коэффициента вариации) в результате изменения гидротермического режима периода вегетации кабачка имеет нелинейный характер и обусловлено взаимодействием генетип-среда. Применение препарата Мицефит оказало значительное влияние на выраженность морфометрических признаков семян кабачка овощного. Взаимодействие генотип-среда нашло выражение в следующем порядке рапределения вариабельности морфометрических признаков семян кабачка: масса (78,2%) → длина (56,6%) → толщина (43,7%) → ширина (40,4%)

Probiotic consortiums: Structure and antagonistic activity against opportunistic bacteria and human normobiota (using the example of <i>Escherichia coli</i>) <i>in vitro</i>

Background. Using probiotic preparations based on consortia of microorganisms not only helps to restore the balance of the intestinal microbiota, but also increases the therapeutic effect of probiotics. Promising sources for obtaining probiotic consortia are milk products that have undergone natural fermentation with the help of spontaneously formed microbial consortia. The aim. To study the structure of five microbial consortia with probiotic properties from naturally fermented milk products and to assess in vitro their antagonistic activity against opportunistic bacteria and a representative of the human normobiota – Escherichia coli. Materials and methods. The structure of bacterial consortia was analyzed by sequencing methods. The antagonistic activity of the consortia was assessed by the disk diffusion method. Results. It has been established that the studied microbial consortiums are represented by Enterococcus spp. and Streptococcus spp. bacteria. In consortiums No. 1, No.  2, and No.  3, Enterococcus bacteria dominated, while in consortiums No.  4 and No. 5, Streptococcus dominated. Antagonistic activity was shown against four isolates of opportunistic bacteria: Klebsiella pneumoniae No.  493, Enterobacter hormaechei No. 372, Staphylococcus aureus No. 4 and Pseudomonas aeruginosa No. 25 IMB, as well as against one representative of the human normobiota – Escherichia coli No. 495. The highest growth delay zone is found in E. coli No. 495 isolate. Three test cultures (K. pneumoniae No. 509, E. coli ATCC25922 and P. aeruginosa No. 3 IMB) exhibited more dense growth around probiotic consortia. Conclusion. The results of the study showed that the effect of probiotic consortia differing in the composition of microorganisms can be neutral and bactericidal. The presence of antagonistic activity in the studied microbial consortia against multiresistant isolates of opportunistic bacteria is a prospect for creating probiotics with antibacterial properties

Micronutrient malnutrition and wasting in adults with pulmonary tuberculosis with and without HIV co-infection in Malawi

BACKGROUND: Wasting and micronutrient malnutrition have not been well characterized in adults with pulmonary tuberculosis. We hypothesized that micronutrient malnutrition is associated with wasting and higher plasma human immunodeficiency virus (HIV) load in adults with pulmonary tuberculosis. METHODS: In a cross-sectional study involving 579 HIV-positive and 222 HIV-negative adults with pulmonary tuberculosis in Zomba, Malawi, anthropometry, plasma HIV load and plasma micronutrient concentrations (retinol, α-tocopherol, carotenoids, zinc, and selenium) were measured. The risk of micronutrient deficiencies was examined at different severity levels of wasting. RESULTS: Body mass index (BMI), plasma retinol, carotenoid and selenium concentrations significantly decreased by increasing tertile of plasma HIV load. There were no significant differences in plasma micronutrient concentrations between HIV-negative individuals and HIV-positive individuals who were in the lowest tertile of plasma HIV load. Plasma vitamin A concentrations <0.70 μmol/L occurred in 61%, and zinc and selenium deficiency occurred in 85% and 87% respectively. Wasting, defined as BMI<18.5 was present in 59% of study participants and was independently associated with a higher risk of low carotenoids, and vitamin A and selenium deficiency. Severe wasting, defined as BMI<16.0 showed the strongest associations with deficiencies in vitamin A, selenium and plasma carotenoids. CONCLUSIONS: These data demonstrate that wasting and higher HIV load in pulmonary tuberculosis are associated with micronutrient malnutrition

Efficiency of Organelle Capture by Microtubules as a Function of Centrosome Nucleation Capacity: General Theory and the Special Case of Polyspermia

Transport of organelles along microtubules is essential for the cell metabolism and morphogenesis. The presented analysis derives the probability that an organelle of a given size comes in contact with the microtubule aster. The question is asked how this measure of functionality of the microtubule aster is controlled by the centrosome. A quantitative model is developed to address this question. It is shown that for the given set of cellular parameters, such as size and total tubulin content, a centrosome nucleation capacity exists that maximizes the probability of the organelle capture. The developed general model is then applied to the capture of the female pronucleus by microtubules assembled on the sperm centrosome, following physiologically polyspermic fertilization. This application highlights an unintuitive reflection of nonlinearity of the nucleated polymerization of the cellular pool of tubulin. The prediction that the sperm centrosome should lower its nucleation capacity in the face of the competition from the other sperm is a stark illustration of the new optimality principle. Overall, the model calls attention to the capabilities of the centrosomal pathway of regulation of the transport-related functionality of the microtubule cytoskeleton. It establishes a quantitative and conceptual framework that can guide experiment design and interpretation

An Experimental and Computational Study of Effects of Microtubule Stabilization on T-Cell Polarity

T-killer cells eliminate infected and cancerous cells with precision by positioning their centrosome near the interface (immunological synapse) with the target cell. The mechanism of centrosome positioning has remained controversial, in particular the role of microtubule dynamics in it. We re-examined the issue in the experimental model of Jurkat cells presented with a T cell receptor-binding artificial substrate, which permits controlled stimulation and reproducible measurements. Neither 1-µM taxol nor 100-nM nocodazole inhibited the centrosome positioning at the “synapse” with the biomimetic substrate. At the same time, in micromolar taxol but not in nanomolar nocodazole the centrosome adopted a distinct peripheral rather than the normally central position within the synapse. This effect was reproduced in a computational energy-minimization model that assumed no microtubule dynamics, but only a taxol-induced increase in the length of the microtubules. Together, the experimental and computational results indicate that microtubule dynamics are not essential for the centrosome positioning, but that the fit of the microtubule array in the deformed body of the conjugated T cell is a major factor. The possibility of modulating the T-cell centrosome position with well-studied drugs and of predicting their effects in silico appears attractive for designing anti-cancer and antiviral therapies

Polo kinase recruitment via the constitutive centromere-associated network at the kinetochore elevates centromeric RNA

The kinetochore, a multi-protein complex assembled on centromeres, is essential to segregate chromosomes during cell division. Deficiencies in kinetochore function can lead to chromosomal instability and aneuploidy-a hallmark of cancer cells. Kinetochore function is controlled by recruitment of regulatory proteins, many of which have been documented, however their function often remains uncharacterized and many are yet to be identified. To identify candidates of kinetochore regulation we used a proteome-wide protein association strategy in budding yeast and detected many proteins that are involved in post-translational modifications such as kinases, phosphatases and histone modifiers. We focused on the Polo-like kinase, Cdc5, and interrogated which cellular components were sensitive to constitutive Cdc5 localization. The kinetochore is particularly sensitive to constitutive Cdc5 kinase activity. Targeting Cdc5 to different kinetochore subcomplexes produced diverse phenotypes, consistent with multiple distinct functions at the kinetochore. We show that targeting Cdc5 to the inner kinetochore, the constitutive centromere-associated network (CCAN), increases the levels of centromeric RNA via an SPT4 dependent mechanism

RAB-5- and DYNAMIN-1-Mediated Endocytosis of EFF-1 Fusogen Controls Cell-Cell Fusion

Cell-cell fusion plays essential roles during fertilization and organogenesis. Previous studies in C. elegans led to the identification of the eukaryotic fusion protein (EFF-1 fusogen), which has structural homology to class II viral fusogens. Transcriptional repression of EFF-1 ensures correct fusion fates, and overexpression of EFF-1 results in embryonic lethality. EFF-1 must be expressed on the surface of both fusing cells; however, little is known regarding how cells regulate EFF-1 surface exposure. Here, we report that EFF-1 is actively removed from the plasma membrane of epidermal cells by dynamin- and RAB-5-dependent endocytosis and accumulates in early endosomes. EFF-1 was transiently localized to apical domains of fusion-competent cells. Effective cell-cell fusion occurred only between pairs of cell membranes in which EFF-1 localized. Downregulation of dynamin or RAB-5 caused EFF-1 mislocalization to all apical membrane domains and excessive fusion. Thus, internalization of EFF-1 is a safety mechanism preventing excessive cell fusion