Bone-specific master transcription factor Runx2 regulates signaling and metabolism related programs in osteoprogenitors

Aim. Runx2 (AML3) transcription factor is the key regulator of osteoblastic lineage progression and is indispensable for the formation of mineral bones. Runx2 expression increases during differentiation of osteoblasts to induce osteoblast-specific genes necessary for the production and deposition of bone mineral matrix. However, Runx2 is also expressed at a lower level in early osteoprogenitors, where its function is less understood. Here we study how Runx2 determines the early stages of osteoblastic commitment using the model system of Runx2 re-introduction in mouse calvaria cells with Runx2 null background. Method. Affymetrix analysis, Western blot analysis and quantitative real-time reverse transcriptase PCR (qRT-PCR) analysis were employed. Results. Gene expression profiling by Affymetrix microarrays revealed that along with the induction of extracellular matrix and bone mineral deposition related phenotypic markers, Runx2 regulates several cell programs related to signaling and metabolism in the early osteoprogenitors. Particularly, Runx2 regulates transcription of genes involved in G-protein coupled signaling network, FGF and BMP/TGF beta signaling pathways and in biogenesis and metabolism pathways of steroid hormones. Conclusion. The data indicate that the lineage specific program, regulated by the master regulatory transcription factor, includes the regulation of cellular signaling and metabolism which may allow the committed cell to react and behave differently in the same microenvironment.Транскрипційний фактор Runx2 (AML3) є важливим регулятором диференціації остеобластів, необхідним для формування кісток. Експресія гена Runx2 зростає в процесі диференціації остеобластів і призводить до активації остеобласт-специфічних генів, відповідальних за продукування мінерального матриксу. Мета роботи полягала у визначенні функції гена Runx2 у попередниках остеобластів, де він експресується на досить низькому рівні. Методи. Ми дослідили функцію гена Runx2 на ранніх стадіях розвитку остеобластів за допомогою модельної системи Runx2-нокаутних клітин скальпів мишей, яким вводили ген Runx2. Результати. При дослідженні експресії геному за допомогою чипів Affymetrix виявлено, що разом із індукцією фенотипових маркерів відкладання зовнішньоклітинного мінерального матриксу ген Runx2 регулює декілька генетичних програм, пов’язаних із сигналінгом і метаболізмом попередників остеобластів. Зокрема, Runx2 регулює гени сигнальної мережі, зчепленої з G-білками, сигнальні шляхи FGF, BMP/TGF, а також ферментативні системи біосинтезу і метаболізму стероїдних гормонів. Висновки. Отримані дані вказують на те, що частина програми спеціалізації, яку виконує ключовий транскрипційний фактор, складається з програмування сигнальних шляхів та метаболізму клітини, дозволяючи ранньоспеціалізованій клітині реагувати та функціонувати певним чином у мікросередовищі.Транскрипционный фактор Runx2 (AML3) является ключевым регулятором дифференциации остеобластов, необходимым для формирования костей. Экспресия гена Runx2 повышается в процессе дифференциации остеобластов, где он активирует остеобласт-специфические гены, необходимые для продукции минерального матрикса. Цель работы состояла в определении функции гена Runx2 в ранних предшественниках остеобластов, где он экспрессируется на достаточно низком уровне. Методы. Мы исследовали, как Runx2 функционирует на ранних стадиях специализации остеобластов с помощью модельной системы внедрения Runx2 в Runx2-нокаутные клетки скальпа мыши. Результаты. При изучении экспресии генома с помощью чипов Affymetrix обнаружено, что вместе с индукцией фенотипичных маркеров, отвечающих за продукцию внеклеточного матрикса, Runx2 регулирует несколько генетических программ, связанных с сигналингом и метаболизмом остеобластов. В частности, Runx2 регулирует гены сигнальной сети, сцепленной с G-белками, сигнальных путей FGF, BMP/TGF, а также системы биосинтеза и метаболизма стероидных гормонов. Выводы. Полученные данные указывают на то, что программа специализации, выполняемая ключевым транскрипционным фактором, включает программирование сигнальных путей и метаболизма клетки, позволяя раннедифференцированной клетке вести себя определенным образом в идентичной микросреде

Observation of time quasicrystal and its transition to superfluid time crystal

We report experimental realization of a quantum time quasicrystal, and its transformation to a quantum time crystal. We study Bose-Einstein condensation of magnons, associated with coherent spin precession, created in a flexible trap in superfluid $^3$He-B. Under a periodic drive with an oscillating magnetic field, the coherent spin precession is stabilized at a frequency smaller than that of the drive, demonstrating spontaneous breaking of discrete time translation symmetry. The induced precession frequency is incommensurate with the drive, and hence the obtained state is a time quasicrystal. When the drive is turned off, the self-sustained coherent precession lives a macroscopically-long time, now representing a time crystal with broken symmetry with respect to continuous time translations. Additionally, the magnon condensate manifests spin superfluidity, justifying calling the obtained state a time supersolid or a time super-crystal

Distribution of Larvae and Pupae of Blackflies (Diptera, Simuliidae) is Dependency upon Speed of Stream

У межах Волинського Полісся преімагінальні фази мошок населяють водойми зі швидкістю течії від 0,20 м/с. Залежно від швидкості течії при якій розвиваються личинки та лялечки, виділено три групи. Установлено, що оптимальною для розвитку преімагінальних фаз Simuliidae є швидкість течії 0,60–0,79 м/с. Within the limits of Volyn Polissya the immature stages of blackflies are inhabited by reservoirs at a speed of stream from a 0,20 meter/second. Depending on speed of stream at which larvae and pupae develop 3 groups are selected. It is set that optimum for development of immature stages of Simuliidae is speed of stream 0,60–0,79 meter/second.Роботу виконано на кафедрі зоології ВНУ ім. Лесі Українк

Exchange biased delta-E effect enables the detection of low frequency pT magnetic fields with simultaneous localization

Delta-E effect sensors are based on magnetoelectric resonators that detune in a magnetic field due to the delta-E effect of the magnetostrictive material. In recent years, such sensors have shown the potential to detect small amplitude and low-frequency magnetic fields. Yet, they all require external magnetic bias fields for optimal operation, which is highly detrimental to their application. Here, we solve this problem by combining the delta-E effect with exchange biased multilayers and operate the resonator in a low-loss torsion mode. It is comprehensively analyzed experimentally and theoretically using various kinds of models. Due to the exchange bias, no external magnetic bias fields are required, but still low detection limits down to [Formula: see text] at 25 Hz are achieved. The potential of this concept is demonstrated with a new operating scheme that permits simultaneous measurement and localization, which is especially desirable for typical biomedical inverse solution problems. The sensor is localized with a minimum spatial resolution of 1 cm while measuring a low-frequency magnetic test signal that can be well reconstructed. Overall, we demonstrate that this class of magnetic field sensors is a significant step towards first biomedical applications and compact large number sensor arrays

Archaea dominate the microbial community in an ecosystem with low-to-moderate temperature and extreme acidity

[Background] The current view suggests that in low-temperature acidic environments, archaea are significantly less abundant than bacteria. Thus, this study of the microbiome of Parys Mountain (Anglesey, UK) sheds light on the generality of this current assumption. Parys Mountain is a historically important copper mine and its acid mine drainage (AMD) water streams are characterised by constant moderate temperatures (8–18 °C), extremely low pH (1.7) and high concentrations of soluble iron and other metal cations.[Results] Metagenomic and SSU rRNA amplicon sequencing of DNA from Parys Mountain revealed a significant proportion of archaea affiliated with Euryarchaeota, which accounted for ca. 67% of the community. Within this phylum, potentially new clades of Thermoplasmata were overrepresented (58%), with the most predominant group being “E-plasma”, alongside low-abundant Cuniculiplasmataceae, ‘Ca. Micrarchaeota’ and ‘Terrestrial Miscellaneous Euryarchaeal Group’ (TMEG) archaea, which were phylogenetically close to Methanomassilicoccales and clustered with counterparts from acidic/moderately acidic settings. In the sediment, archaea and Thermoplasmata contributed the highest numbers in V3-V4 amplicon reads, in contrast with the water body community, where Proteobacteria, Nitrospirae, Acidobacteria and Actinobacteria outnumbered archaea. Cultivation efforts revealed the abundance of archaeal sequences closely related to Cuniculiplasma divulgatum in an enrichment culture established from the filterable fraction of the water sample. Enrichment cultures with unfiltered samples showed the presence of Ferrimicrobium acidiphilum, C. divulgatum, ‘Ca. Mancarchaeum acidiphilum Mia14’, ‘Ca. Micrarchaeota’-related and diverse minor (< 2%) bacterial metagenomic reads.[Conclusion] Contrary to expectation, our study showed a high abundance of archaea in this extremely acidic mine-impacted environment. Further, archaeal populations were dominated by one particular group, suggesting that they are functionally important. The prevalence of archaea over bacteria in these microbiomes and their spatial distribution patterns represents a novel and important advance in our understanding of acidophile ecology. We also demonstrated a procedure for the specific enrichment of cell wall-deficient members of the archaeal component of this community, although the large fraction of archaeal taxa remained unculturable. Lastly, we identified a separate clustering of globally occurring acidophilic members of TMEG that collectively belong to a distinct order within Thermoplasmata with yet unclear functional roles in the ecosystem.The work of OVG, PNG and SVT was supported by the Royal Society UK-Russia Exchange Grant #IE 160224 (RFBR 16-54-10072 КО project). OVG and PNG acknowledge ERA Net IB2 Project MetaCat through UK Biotechnology and Biological Sciences Research Council (BBSRC) Grant BB/M029085/1 and the support of the Centre of Environmental Biotechnology Project funded by the European Regional Development Fund (ERDF) through the Welsh Government. RB and PNG acknowledge the support of the Supercomputing Wales project, which is part-funded by the European Regional Development Fund (ERDF) via the Welsh Government. The work of AAK and IVK was supported by the Russian Science Foundation grant # 18-44-04024. MF acknowledges grants PCIN-2014-107 (within ERA NET IB2 grant ERA-IB-14-030—MetaCat), PCIN-2017-078 (within the Marine Biotechnology ERA-NET (ERA-MBT) funded under the European Commission’s Seventh Framework Programme, 2013-2017, Grant agreement 604814), BIO2014-54494-R and BIO2017-85522-R from the Spanish Ministry of Economy and Competitiveness

Regulation of vascular smooth muscle cell calcification by syndecan-4/FGF-2/PKCα signaling and cross-talk with TGFβ

Aims: Vascular calcification is a major cause of morbidity and mortality. Fibroblast growth factor-2 (FGF-2) plays an instructive role in osteogenesis and bone development, but its role in vascular calcification was unknown. Therefore, we investigated the involvement of FGF-2 in vascular calcification and determined the mechanism by which it regulates this process. Methods and Results: We demonstrate that FGF-2 expression is increased in vascular smooth muscle cells (VSMCs) induced to deposit a mineralized matrix by incubation with β-glycerophosphate. FGF-2 is also localized to sites of calcification within human atherosclerotic plaques. The expression of syndecan-4, a heparan sulfate proteoglycan which regulates FGF-2 signaling, is also increased in mineralizing VSMCs and co-localizes with FGF-2 in human calcified atherosclerotic plaques. Exogenous FGF-2 inhibits VSMC mineralization, and this inhibition is reduced when syndecan-4 expression is knocked-down using siRNA. Biochemical inhibition of FGFR signaling using a pan FGFR inhibitor (BGJ398) or knocking-down syndecan-4 expression in VSMCs using siRNA increases VSMC mineralization. These increases are prevented by inhibiting transforming growth factor-β (TGFβ) signaling with SB431542, suggesting cross-talk between FGF-2 and TGFβ signaling is crucial for the regulation of VSMC mineralization. Syndecan-4 can also regulate FGF-2 signaling directly via protein kinase Cα (PKCα) activation. Biochemical inhibition of PKCα activity using Gö6976, or siRNA-mediated suppression of PKCα expression increases VSMC mineralization; this increase is also prevented with SB431542. Finally, the ability of FGF-2 to inhibit VSMC mineralization is reduced when PKCα expression is knocked-down. Conclusion: This is the first demonstration that syndecan-4 promotes FGF-2 signaling, and in turn, suppresses VSMC mineralization by down-regulating TGFβ signaling. Our discoveries that FGF-2 and syndecan-4 expression is increased in mineralizing VSMCs and that PKCα regulates FGF-2 and TGFβ signaling in VSMCs suggests that the syndecan-4/FGF-2/TGFβ signaling axis could represent a new therapeutic target for vascular calcification

GPR30 Deficiency Causes Increased Bone Mass, Mineralization, and Growth Plate Proliferative Activity in Male Mice

Estrogen regulation of the male skeleton was first clearly demonstrated in patients with aromatase deficiency or a mutation in the ERα gene. Estrogen action on the skeleton is thought to occur mainly through the action of the nuclear receptors ERα and ERβ. Recently, in vitro studies have shown that the G protein–coupled receptor GPR30 is a functional estrogen receptor (ER). GPR30-deficient mouse models have been generated to study the in vivo function of this protein; however, its in vivo role in the male skeleton remains underexplored. We have characterized size, body composition, and bone mass in adult male Gpr30 knockout (KO) mice and their wild-type (WT) littermates. Gpr30 KO mice weighed more and had greater nasal-anal length (p < .001). Both lean mass and percent body fat were increased in the KO mice. Femur length was greater in Gpr30 KO mice, as was whole-body, spine, and femoral areal bone mineral density (p < .01). Gpr30 KO mice showed increased trabecular bone volume (p < .01) and cortical thickness (p < .001). Mineralized surface was increased in Gpr30 KO mice (p < .05). Bromodeoxyuridine (BrdU) labeling showed greater proliferation in the growth plate of Gpr30 KO mice (p < .05). Under osteogenic culture conditions, Gpr30 KO femoral bone marrow cells produced fewer alkaline phosphatase–positive colonies in early differentiating osteoblast cultures but showed increased mineralized nodule deposition in mature osteoblast cultures. Serum insulin-like growth factor 1 (IGF-1) levels were not different. These data suggest that in male mice, GPR30 action contributes to regulation of bone mass, size, and microarchitecture by a mechanism that does not require changes in circulating IGF-1. © 2011 American Society for Bone and Mineral Research