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Characterization of long non-coding telomeric repeat-containing RNAs in sperm of normozoospermic and oligoasthenozoospermic men as new biomarker of idiopathic male infertility. We conducted an observational prospective study with two groups of men with normal or orligoasthenozoospermic spermiogram, aged 40 and above. Fertility parameters were analyzed in men undergoing intracytoplasmic sperm injection with donor oocytes, to avoid the female factor. Telomeric RNAs and telomere length were measured by quantitative fluorescent in situ hybridization. Data from seminal parameters and in-vitro fertilization were assessed according to IVIRMA protocols. Patients with oligoasthenozoospermia, who had worse seminal parameters, also obtained embryos with lower inner-cell-mass quality (p = 0.04), despite using donor oocytes. While mean levels of telomeric RNAs were similar for both groups, the percentage of spermatozoa with more than 3 foci was higher in oligoasthenozoospermic men (p = 0.02). Regarding telomere length, oligoasthenozoospermic men had shorter mean, a higher accumulation of short telomeres (15th percentile; p = 0.03) and a lower percentage of very-long telomeres (85th percentile; p = 0.01). Finally, a positive correlation was found between telomeric-RNAs intensity and total progressive motility in the spermatozoa of normozoospermic patients (r = 0.5; p = 0.03). Telomeric parameters were altered in the spermatozoa of the oligoasthenozoospermic group, which also showed lower quality embryos. Interestingly, in the normozoospermic group, a correlation was found between progressive motility and telomeric RNA levels, suggesting that they could be a good biomarker of sperm quality. Further studies are required to confirm these results and translate them into the clinical practice. Trial registration number: 1711-MAD-109-CB, 07/07/2021. [ABSTRACT FROM AUTHOR]

RESUMO Este artigo analisa algumas relações entre o problema agrário e o processo de desenvolvimento capitalista no Brasil. Argumenta que o aumento da produtividade associado ao aprofundamento da divisão social do trabalho altera as relações de produção no setor agrícola. O campesinato inicialmente ligado aos latifúndios feudais torna-se mão-de-obra assalariada contratada sazonalmente para as fazendas capitalistas. Nesse contexto, o problema fundiário surge como uma questão financeira associada basicamente ao preço da terra. Com isso, a reforma agrária baseada na compra de grandes áreas pelo governo não será uma solução para o problema agrário, pois apoiará o aumento do preço da terra.

Composto por cinco seções principais, o artigo almeja, de uma forma introdutória e concisa, oferecer um panorama do tabuleiro político-ideológico e teórico que caracteriza as posições mais significativas a propósito da “crise ambiental” contemporânea. As quatro seções iniciais se destinam a esboçar críticas ao “ambientalismo pró-capital”, ao neofascismo antiecológico, ao ecofascismo e, por fim, às falácias de tipo “pós-moderno”, exemplificadas por algumas das ideias de Bruno Latour. Na quinta seção, finalmente, são apresentados contrapontos emancipatórios aos discursos e práticas mencionados nas seções precedentes, tanto no que tange a contrapontos acadêmicos ou teóricos (oriundos, sobretudo, do marxismo e de correntes libertárias) quanto no que diz respeito a práticas espaciais de resistência (ou, melhor ainda, “r-existência”) dos agentes e sujeitos coletivos, em suas lutas por terra, por território e, em última instância, pela Terra.

In this article I analyze the tikmũ,ũn recent history through their sacrificial practices and the relationship they establish with the yãmĩyxop (group of singing spirits). As I analyze historically the process of "whitening" the tikmũ,ũn land, which consists of its desertification and reterritorialization through extensive livestock, I observe that there are different territories crossing indigenous and non-indigenous bodies. The article develops two arguments. The first one is that sacrifice mobilizes a construction of the body of the tikmũ,ũn person, which places it on other paths, different from the reterritorialization in agriculture and cattle raising. The second is that if whites and tikmũ,ũn people mobilize different territories in their bodies, this allows me to say that if the point of view is in the body, then possibly it is historical and territorial and, in front of the land, the variable factor is less a culture than a nature. [ABSTRACT FROM AUTHOR]

AbstractSulfur mustard (SM) exposure has delayed harmful effects, including premature biological aging. This study aimed to evaluate the expression of aging markers (i.e., ANRIL, P16INK4a, TBX2, and TERRA) and assess their correlation with the severity of SM exposure in the long term. The study was conducted on two volunteer groups. 1) SM-exposed group, exposed to SM once in 1987 during the war; divided into three subgroups based on the injury severity, asymptomatic (without any clinical signs), mild, and severe; 2) Non-exposed group. In the SM-exposed group, ANRIL transcript was decreased, especially in subgroups of mild and severe. TBX2 transcript was also decreased in the total SM-exposed group. This decrease was more significant in the mild and severe subgroups than in asymptomatic ones. P16INK4a transcript was increased in the SM-exposed group, especially in the asymptomatic subgroup. The increase in TERRA transcript was also significant in all subgroups. There was a positive correlation between the TERRA transcript and the severity of injury, while this correlation was negative for the ANRIL. It is concluded that the delayed toxicity of SM may be associated with dysregulation of aging markers leading to premature cellular aging. These markers’ alterations differed according to the severity of SM injury. [ABSTRACT FROM AUTHOR]

In billion years of evolution, eukaryotes preserved the chromosome ends with arrays of guanine repeats surrounded by thymines and adenines, which can form stacks of four‐stranded planar structure known as G‐quadruplex (G4). The rationale behind the evolutionary conservation of the G4 structure at the telomere remained elusive. Our recent study has shed light on this matter by revealing that telomere G4 undergoes oscillation between at least two distinct folded conformations. Additionally, tumor suppressor BRCA2 exhibits a unique mode of interaction with telomere G4. To elaborate, BRCA2 directly interacts with G‐triplex (G3)‐derived intermediates that form during the interconversion of the two different G4 states. In doing so, BRCA2 remodels the G4, facilitating the restart of stalled replication forks. In this review, we succinctly summarize the findings regarding the dynamicity of telomeric G4, emphasize its importance in maintaining telomere replication homeostasis, and the physiological consequences of losing G4 dynamicity at the telomere. [ABSTRACT FROM AUTHOR]

Francesco d'Assisi cantore della terra con i «coloriti flori et erba» e non solo il Francesco amante degli animali testimoniato da una lunga tradizione popolare. Il capovolgimento di prospettiva è anche l'esito della Laudato si' che induce a una rilettura delle biografie del Santo con l'ottica dei suoi scritti e in particolare del Cantico di frate Sole. Ne risulta una terra madre con connotazione cristologica, sociale e politica, antidoto a ogni tentazione esclusivistica, insita nel dualismo tanto antropocentrico, quanto ecocentrico. La terra, in quanto madre che nutre e governa, si dimostra quindi paradigma di una nuova economia, che non permette al mercato, cioè alla finanza, di fissare il prezzo delle cose, ovvero di stabilirne il valore sulla base della convenienza dei potenti. Il valore delle cose deve essere fissato, invece, dalla terra, mensa di tutti, che sovviene a ogni necessità, riconosciuta tale da una fraternità governata dalla cura materna. [ABSTRACT FROM AUTHOR]

Este artigo apresenta a contribuição teórica de Hannah Arendt sobre o significado da alienação do mundo e da Terra, bem como sua relação com a sociedade do consumo. Arendt traz o diagnóstico de uma crise que localiza o ser humano cada vez mais desconectado da Terra, do mundo e da pluralidade humana. Junto a isso, a pensadora judio-alemã expõe como a centralidade da atividade do trabalho põe também o consumo no centro de nosso processo vital e de nossas experiências contemporâneas. Baseando-nos principalmente na obra A condição humana (2020), mostramos os riscos que o nosso modo de vida moderno acarreta para a existência humana, para o mundo político e para a Terra. Por fim, indicamos que mais que nunca se mostra inadiável uma educação ambiental frente a assunção de nossa responsabilidade com o mundo e a Terra, de modo que frente às alienações, é nosso pertencimento ao habitat humano e natural que precisam ser encarados de frente.

AbstractEukaryotic cells without telomerase experience progressively shorter telomeres with each round of cell division until cell cycle arrest is initiated, leading to replicative senescence. When yeast TLC1, which encodes the RNA template of telomerase, is deleted, senescence is accompanied by increased expression of TERRA (non-coding telomere repeat-containing RNA). Deletion of Npl3, an RNA-processing protein with telomere maintenance functions, accelerates senescence in tlc1Δ cells and significantly increases TERRA levels. Using genetic approaches, we set out to determine how Npl3 is involved in regulating TERRA expression and maintaining telomere homeostasis. Even though Npl3 regulates hyperrecombination, we found that Npl3 does not help resolve RNA:DNA hybrids formed during TERRA synthesis in the same way as RNase H1 and H2. Furthermore, Rad52 is still required for cells to escape senescence by telomere recombination in the absence of Npl3. Npl3 also works separately from the THO/TREX pathway for processing nascent RNA for nuclear export. However, deleting Dot1, a histone methyltransferase involved in tethering telomeres to the nuclear periphery, rescued the accelerated senescence phenotype of npl3Δ cells. Thus, our study suggests that Npl3 plays an additional role in regulating cellular senescence outside of RNA:DNA hybrid resolution and co-transcriptional processing. [ABSTRACT FROM AUTHOR]

Telomeres are special nucleoprotein structures that protect the ends of linear chromosomes. Telomeric DNA is composed of 6-nucleotide repeats that are synthesized by telomerase, a specialized DNA polymerase. According to Alexey Olovnikov's telomere theory of aging, replicative aging in somatic cells is caused by telomere shortening during cell division. Even before telomerase was discovered, he predicted in 1973 that telomere elongation occurs only in certain types of cells, such as germ cells, stem cells, and tumor cells. In this review, we explore the stages of animal ontogenesis where telomere elongation takes place and the mechanisms of telomere maintenance during gametogenesis and embryogenesis. The mechanism of homologous recombination that controls telomere length tuning during early embryogenesis is discussed. The advancement of modern cell technologies, including those based on induced pluripotent stem cells, inevitably raises the issue of genome stability in clinically relevant cell lines. Here we compare telomere maintenance mechanisms in embryonic and induced pluripotent stem cells, as well as discuss how telomere stability can be influenced during development. [ABSTRACT FROM AUTHOR]

TERRA is a class of telomeric repeat-containing RNAs that are expressed from telomeres in multiple organisms. TERRA transcripts play key roles in telomere maintenance and their physiological levels are essential to maintain the integrity of telomeric DNA. Indeed, deregulated TERRA expression or its altered localization can impact telomere stability by multiple mechanisms including fueling transcription-replication conflicts, promoting resection of chromosome ends, altering the telomeric chromatin, and supporting homologous recombination. Therefore, a fine-tuned control of TERRA is important to maintain the integrity of the genome. Several studies have reported that different cell lines express substantially different levels of TERRA. Most importantly, TERRA levels markedly vary among telomeres of a given cell type, indicating the existence of telomere-specific regulatory mechanisms which may help coordinate TERRA functions. TERRA molecules contain distinct subtelomeric sequences, depending on their telomere of origin, which may instruct specific post-transcriptional modifications or mediate distinct functions. In addition, all TERRA transcripts share a repetitive G-rich sequence at their 3′ end which can form DNA:RNA hybrids and fold into G-quadruplex structures. Both structures are involved in TERRA functions and can critically affect telomere stability. In this review, we examine the mechanisms controlling TERRA levels and the impact of their telomere-specific regulation on telomere stability. We compare evidence obtained in different model organisms, discussing recent advances as well as controversies in the field. Furthermore, we discuss the importance of DNA:RNA hybrids and G-quadruplex structures in the context of TERRA biology and telomere maintenance. [Display omitted] • Transcription of telomeric repeats contributes to telomere function and stability. • TERRA expression is regulated in a telomere-specific manner in various organisms. • Transcriptional control and RNA decay mechanisms coordinate TERRA expression regulation. • Altered TERRA levels can precipitate telomere dysfunction and genome instability. • Telomeric R-loops and RNA G quadruplexes contribute to TERRA functions. [ABSTRACT FROM AUTHOR]

Environmental issues, in particular climate change, have assumed increasing urgency, and have become even more acute with the Covid-19 pandemic and the globally rise of hunger and inequality. Despite this urgency, international demands and prices for agricultural and mineral commodities have been a driving force behind the expansion of the agricultural frontier (changes in land use), particularly with the increase in monocultures, extensive livestock farming and mineral extraction for export. This has generated debates, studies and reflections in Political Economy, Political Ecology, among other areas of knowledge, but has this urgency raised reflections and research on the importance of land and the agrarian issue? Based on some political (dis)agreements and measures, and in dialogue with international literature, this text seeks to contribute to the so-called Critical Agrarian Studies, formulating, conceptually and politically, a notion of "eco-agrarian issue", analyzing and critically interpreting agrarian extractivism in the Brazilian agricultural frontier. [ABSTRACT FROM AUTHOR]

Resumo Em meados da primeira década dos anos 2000 houve um reconhecimento da cooperação sul-sul (CSS) pela comunidade de doadores e agências multilaterais, destacando a relevância estratégica das experiências de desenvolvimento dos chamados países emergentes - compreendidas como mais adequadas às nações de um heterogêneo sul global do que os planos traçados pelos doadores tradicionais do norte. A busca por horizontalidade nas parcerias, portanto, tornou-se um instrumento para promover uma nova arquitetura da ajuda internacional. Neste artigo procuro explorar a noção de similaridade, fortemente mobilizada pelas iniciativas de CSS brasileiras com países da África, entendendo-a como uma ferramenta para traçar comparações entre territórios singulares. Para tanto, considero as analogias produzidas no âmbito do “Projeto Embrapa-Moçambique”, também conhecido como “Projeto Paralelos”, que se apoiou nas similaridades edafoclimáticas entre as Savanas moçambicanas e o Cerrado brasileiro, para conduzir um mapeamento por satélite das potencialidades dos recursos naturais deste país africano. O principal produto deste levantamento foi a plataforma WebGIS, uma base de dados biofísicos e socioeconômicos georreferenciados, que visa conferir subsídios tanto para melhorar a gestão destas informações quanto para promover o desenvolvimento sustentável da agricultura moçambicana. Meu objetivo é descrever como diferentes conceituações sobre a terra - planeta, território, solo, mercadoria, recurso natural - proliferam a partir do estabelecimento deste conjunto de dados. Particularmente, analiso como estes permitem transformar a terra em um ativo, sob o olhar de alguns dos possíveis usuários do WebGIS: agentes do mercado financeiro global, que buscam ambientes seguros para seus negócios nada horizontais, mas ainda assim agenciados por políticas de promoção do desenvolvimento.

Nel campo della transitional justice, è stata a lungo ignorata l’importanza delle diseguaglianze economiche e della marginalizzazione sociale fra i fattori di rischio per la pace. Queste oppressioni, incorporate nelle strutture stesse della società, costituiscono invece il terreno più fertile per la rinascita della violenza diretta. L’articolo si apre con l’inquadramento teorico del concetto di violenza strutturale, e prosegue con l’esplorazione del legame tra quest’ultima e la giustizia di transizione. Dopodiché, procede con l’illustrazione delle principali manifestazioni di violenza strutturale che affliggono la società colombiana e analizza le misure specifiche adottate per affrontarle nel quadro dell’Accordo di Pace del 2016 fra Governo e FARC-EP.

Eukaryotic telomeres are transcribed into the long noncoding RNA TERRA. A fraction of TERRA remains associated with telomeres by forming RNA:DNA hybrids dubbed telR‐loops. TERRA and telR‐loops are essential to promote telomere elongation in human cancer cells that maintain telomeres through a homology‐directed repair pathway known as alternative lengthening of telomeres or ALT. However, TERRA and telR‐loops compromise telomere integrity and cell viability if their levels are not finely tuned. The study of telomere transcription in ALT cells will enormously expand our understanding of the ALT mechanism and of how genome integrity is maintained. Moreover, telomere transcription, TERRA and telR‐loops are likely to become exceptionally suited targets for the development of novel anti‐cancer therapies. [ABSTRACT FROM AUTHOR]

Driven by global sustainability goals, understanding land surface temperature (LST) in urban thermal environments (UTE) is crucial. This study analyses remotely sensed LST data from Aqua and Terra satellites in a rapidly growing non-tier Indian city. It uniquely integrates remote sensing and soft computational analysis to predict daytime LST using artificial neural networks (ANN). The study is categorized based on transfer functions and hyper-parameters to enhance the comprehension of LST prediction and simulation scenarios by employing Back Propagation Neural Network (BPNN) model. Results indicate that the tansig transfer function yields the best performance overall in Aqua and Terra LST prediction, while purelin performs the least effectively. This study provides evidence that soft computing techniques effectively estimate LST data, offering a valuable solution for data scarcity issues. However, the findings are specific to the study area and may vary elsewhere. Exploring alternative methods and incorporating data from other areas could potentially improve accuracy and overall performance. Future research could focus on investigating the mechanisms behind different methods and their interactions with various factors. Additionally, integrating other variables like vegetation index, soil moisture, and others could contribute to a more holistic understanding of LST dynamics and enhance predictive capabilities. [ABSTRACT FROM AUTHOR]

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Cyanobacterial harmful algal blooms (CyanoHABs) pose significant environmental threats in China's large, shallow, and turbid lakes. Current satellite remote sensing methods for monitoring CyanoHABs in turbid water are limited in accuracy and frequency. The commonly used spectral index approaches often misidentify CyanoHABs by highly turbid water, and the segmentation threshold algorithms are not robust enough. Additionally, the dynamic nature of CyanoHABs requires high temporal resolution, which commonly used remote sensing data fail to provide. This study proposed a novel monitoring method utilizing a new spectral index, Anti-Turbid Algal Bloom Index (ATBI), specifically designed to minimize the impact of highly turbid water, coupled with an iterative triangle algorithm for automated ATBI threshold determination. We applied this approach to MODIS data from both Terra and Aqua satellites, achieving a temporal resolution of 0.5 days. The validation results show that the new method has a high accuracy with an F1-score of 0.85, which is higher than the commonly used algorithms with an F1-score of approximately 0.60. Utilizing this approach, we analyzed the spatiotemporal distribution of CyanoHABs in China's large lakes from 2000 to 2022, including Lakes Hulunhu, Chaohu and Taihu. Notably, Lake Hulunhu exhibited an increase in frequency and duration of CyanoHABs, while Lakes Chaohu and Taihu showed a rise in duration but a decline in frequency post 2018 and 2017, respectively. Air temperature and wind speed are critical factors influencing CyanoHABs variations in these lakes. Comparative analysis using data from Terra, Aqua, and both satellites combined demonstrated that the integrated data captures more accurate CyanoHABs information. These findings showed that our method can enhance CyanoHABs monitoring capabilities and offer insights for future research.

در این پژوهش هدف ارزیابی پایگاه داده­های بارش با مقادیر مشاهداتی به‌صورت زمانی (ماهانه و فصلی) و مکانی (دو حالت نقطه­ای (40 ایستگاه سینوپتیک) و سطحی (30 حوضه آبریز درجه دو و چهار اقلیم))، در کشور به‌عنوان منطقه مطالعاتی می­باشد. بدین منظور ابتدا داده­های مشاهداتی (100 ایستگاه در مقیاس روزانه) و پایگاه­های جهانی بارش شامل ERA5، MRRRA2، GLDAS و TERRA (با تفکیک مکانی مختلف در مقیاس ماهانه) طی دوره زمانی 1398-1366 گرد­آوری و استخراج گردید. سپس براساس شاخص خشکی، طبقه­بندی اقلیمی ایستگاه­ها و حوضه­ها انجام شده است. ارزیابی دقت پایگاه‌ها با استفاده از معیارهای ضریب همبستگی (R)، میانگین خطای اریبی (MBE) و مجذور میانگین مربع خطا استانداردشده (NRMSE) استفاده شده است. نتایج معیارهای در بارش ایستگاهی نشان داد که پایگاه TERRA در همه فصول به‌جز تابستان و در اقلیم­های فراخشک، خشک و نیمه‌خشک، با متوسط 70 درصد ضریب همبستگی بالاتر از 5/0 (R) و میزان خطای 90 درصد کم‌تر از 5/0 (NRMSE) نسبت به بقیه­ها پایگاه­ها و در اقلیم مرطوب پایگاه ERA5 عملکرد بهتری را از خود نشان داد. در بارش حوضه­ای نیز نشان داد به‌ترتیب پایگاه TERRA در اقلیم فرا­خشک، پایگاه­های ERA5، MRRRA2، GLDAS و TERRA در اقلیم خشک، پایگاه­های ERA5 و TERRA در اقلیم نیمه‌خشک و پایگاه‌های ERA5، TERRA و MERRA2 در اقلیم مرطوب با متوسط 80 درصد ضریب همبستگی بالاتر از 5/0 و میزان خطای 70 درصد کم‌تر از 5/0 کارایی مناسب‌تری را نشان دادند. به‌طور کلی پایگاه TERRA در حالت نقطه­ای، سطحی و اقلیمی از عملکرد خوبی برخوردار بوده است که می‌توان گفت به‌علت دقت مکانی بالای آن بوده باشد.

Telomeres are terminal structures that define the ends of linear chromosomes. They harbour specialized ribonucleoprotein complexes which play a major role in genome integrity by preventing unscheduled DNA damage repair events. Genes located adjacent to telomere repeat sequences are repressed by a phenomenon called telomere position effect (TPE) via epigenetic silencing. RNA surveillance pathways post-transcriptionally regulate any leaky transcripts arising from the telomeres. Recently, multiple non-coding RNA species originate from telomere ends, namely, TERRA (telomeric repeat‐containing RNA), ARRET, sub-telomeric XUTs and sub-telomeric CUTs have been identified. In this study, we report a role for the transcription termination complex (Rtt103-Rai1-Rat1) in regulating the abundance of the sub-telomeric transcripts in a transcription-dependent manner. We show that the Rtt103 mutants have elevated levels of TERRA and other sub-telomeric transcripts that are usually silenced. Our study suggests that Rtt103 potentially recruits the exonuclease, Rat1 in a RNA polymerase II dependent manner to degrade these transcripts and regulate their levels in the cell.

Background: Most women who are treated at in vitro fertilization (IVF) clinics have trouble conceiving due to ovarian failure (OF), which seems to be associated to short telomeres and reduced or absent telomerase activity in their granulosa cells. Indeed, telomere pathways are involved in organ dysfunction. However, sexual steroids can stimulate the expression of the telomerase gene and have been successfully used to prevent telomere attrition. Thus, a strategy to improve IVF outcomes in women with OF could be telomerase reactivation using sexual steroids. Methods: We conducted a double-blind, placebo-controlled study. Patients with diminished ovarian reserve were randomized to Danazol or placebo for 3 months. We included patients with normal ovarian reserve in the study as untreated controls. Patients and controls underwent several ovarian stimulations (OSs). Telomere and IVF parameters were assessed. Results: We found that the mean telomere length in blood and the percentage of short and long telomeres were similar throughout the 3 months of treatment with Danazol. Remarkably, while the number of cells with one telomeric repeat-containing RNA (TERRA) focus decreased (p?=?0.04) after the first month of Danazol treatment, the number of cells with 2 to 4 TERRA foci increased (p?=?0.02). Regarding fertility, no differences were found in the antral follicle count. Interestingly, in OS performed after the trial, all Danazol-treated patients had a better MII oocyte rate compared to OS performed before the pilot study. EudraCT number: 2018-004400-19. Conclusions: Danazol treatment seemed to affect telomere maintenance, since both the number of TERRA foci and the ratio of MII oocytes changed. However, further research is needed to confirm these results.

RESUMO Trata-se de uma reflexão despertada pela participação da autora em uma Conferência Internacional sobre o Futuro dos Povos indígenas, organizada no ano 2000 pelo Centro de Estudos Beduínos da Universidade Ben-Gurion, em Beer Sheva, no Negev, em Israel. Múltiplos temas se entrelaçam, em breves pinceladas. A condição dos beduínos, pouco conhecida no Brasil, apresenta semelhanças com a de povos indígenas, no embate com Estados nacionais e exclusão em uma sociedade desigual. A autora aponta sua descoberta do poder da poesia oral beduína, em parte também escrita por protagonistas orais ou em versão árabe/inglês pelo estudioso Clinton Bailey. Nas entrelinhas, os sentimentos conflitantes de uma judia, neta de imigrantes de Odessa, fugitivos ainda do czarismo, educada com a utopia da defesa incondicional de todos os povos do mundo e da condenação de qualquer holocausto. Escrever sobre essa viagem é expressar, mesmo com décadas de atraso, a admiração pelos Beduínos e em especial por Ismael Abu-Saad, diretor do Centro, por seus livros, artigos e defesa dos direitos dos povos e excluídos, fundamentais para este ensaio.

The alteration of the Earth's surface due to urbanization and the formation of urban heat islands is one of the most evident and widely discussed anthropogenic impacts on Earth's microclimate. The elevated land surface temperature in the urban perimeter compared with the surrounding non-urban area is known as the surface urban heat island (SUHI) effect. India has experienced swift urban growth over the past few decades, and this trend is expected to persist in years to come. The literature published on SUHI in India focuses only on a few specific cities, and there is limited understanding of its geospatial variation across a broader region and its long-term trend. Here, we present one of the first studies exploring the long-term diurnal (daytime, and nighttime), seasonal, and annual characteristics of SUHI in the 20 largest urban centers of India and its neighboring countries. The study highlights a statistically significant (95% confidence interval) rise in nighttime surface temperatures across major cities based on a linear fit over 23 years (2000–2023) of MODIS land surface temperature satellite observations. The nighttime SUHI was found to be more conspicuous, positive, and consistent when compared with daytime satellite observations. The nighttime SUHI for April–May–June representing the pre-monsoon and onset of monsoon months for the top 10 cities, ranged from 0.92 to 2.33 °C; for December–January–February, representing the winter season, it ranged from 1.38 to 2.63 °C. In general, the total change in the nighttime SUHI based on linear fit (2000–2023) for the top ten cities showed warming over the urban region ranging from 2.04 to 3.7 °C. The highest warming trend was observed during the months of May–June–July (3.7 and 3.01 °C) in Ahmedabad and Delhi, cities that have undergone rapid urbanization in the last two to three decades. The study identified strongly positive annual SUHI intensity during nighttime, and weakly negative to moderately positive annual SUHI intensity during daytime, for major cities. Jaipur (India), Lahore (Pakistan), Dhaka (Bangladesh), and Colombo (Sri Lanka) showed a nighttime SUHI intensity of 2.17, 2.33, 0.32, and 0.21 °C, respectively, during the months of April–May–June, and a nighttime SUHI intensity of 2.63, 1.68, 0.94, 0.33 °C, respectively, for the months of December–January–February (2000–2023). It is apparent that the geographical location (inland/coastal) of the city has a high influence on the daytime and nighttime SUHI patterns. The current research is intended to help city planners and policymakers better understand SUHI intensity (day and night/seasonal basis) for developing strategies to mitigate urban heat island effects. [ABSTRACT FROM AUTHOR]

The first NOAA full-mission reanalysis (RAN1) of the sea surface temperature (SST) from the two Moderate Resolution Imaging Spectroradiometers (MODIS) onboard Terra (24 February 2000–present) and Aqua (4 July 2002–present) was performed. The dataset was produced using the NOAA Advanced Clear-Sky Processor for Ocean (ACSPO) enterprise SST system from Collection 6.1 brightness temperatures (BTs) in three MODIS thermal emissive bands centered at 3.7, 11, and 12 µm with a spatial resolution of 1 km at nadir. In the initial stages of reprocessing, several instabilities in the MODIS SST time series were observed. In particular, Terra SSTs and corresponding BTs showed three 'steps': two on 30 October 2000 and 2 July 2001 (due to changes in the MODIS operating mode) and one on 25 April 2020 (due to a change in its nominal blackbody temperature, BBT, from 290 to 285 K). Additionally, spikes up to several tenths of a kelvin were observed during the quarterly warm-up/cool-down (WUCD) exercises, when the Terra MODIS BBT was varied. Systematic gradual drifts of ~0.025 K/decade were also seen in both Aqua and Terra SSTs over their full missions due to drifting BTs. These calibration instabilities were mitigated by debiasing MODIS BTs using the time series of observed minus modeled ('O-M') BTs. The RAN1 dataset was evaluated via comparisons with various in situ SSTs. The data meet the NOAA specifications for accuracy (±0.2 K) and precision (0.6 K), often by a wide margin, in a clear-sky ocean domain of 19–21%. The long-term SST drift is typically less than 0.01 K/decade for all MODIS SSTs, except for the daytime 'subskin' SST, for which the drift is ~0.02 K/decade. The MODIS RAN1 dataset is archived at NOAA CoastWatch and updated monthly in a delayed mode with a latency of two months. Additional archival with NASA JPL PO.DAAC is being discussed. [ABSTRACT FROM AUTHOR]

Telomere dysfunction is implicated in vascular aging and shorter leucocyte telomeres are associated with an increased risk of atherosclerosis, myocardial infarction, and heart failure. Another pathophysiological mechanism that explains the causal relationship between telomere shortening and atherosclerosis development focuses on the clonal hematopoiesis of indeterminate potential (CHIP), which represents a new and independent risk factor in atherosclerotic cardiovascular diseases. Since telomere attrition has a central role in driving vascular senescence, understanding telomere biology is essential to modulate the deleterious consequences of vascular aging and its cardiovascular disease-related manifestations. Emerging evidence indicates that a class of long noncoding RNAs transcribed at telomeres, known as TERRA for "TElomeric Repeat-containing RNA", actively participates in the mechanisms regulating telomere maintenance and chromosome end protection. However, the multiple biological functions of TERRA remain to be largely elucidated. In particular, the role of TERRA in vascular biology is surprisingly unknown. In this review, we discuss the current knowledge of TERRA and its roles in telomere biology. Additionally, we outline the pieces of evidence that exist regarding the relationship between TERRA dysregulation and disease. Finally, we speculate on how a comprehensive understanding of TERRA transcription in the cardiovascular system may provide valuable insights into telomere-associated vascular aging, offering great potential for new therapeutic approaches. [ABSTRACT FROM AUTHOR]

Long, noncoding RNAs (lncRNAs) are indispensable for normal cell physiology and, consequently, are tightly regulated in human cells. Yet, unlike mRNA, substantially less is known about the mechanisms for lncRNA degradation. It is important to delineate the regulatory control of lncRNA degradation, particularly for lncRNA telomeric repeat-containing RNA (TERRA), as the TERRA-telomere R-loops dictate cell cycle progression and genomic stability. We now report that the exosome complex component Exosc9 degrades lncRNA TERRA in human mammary epithelial cells. Heterochromatin protein 1 alpha (HP1α) recruits Exosc9 to the telomeres; specifically, the SUMO-modified form of HP1α supports interaction with Exosc9 and, as previously reported, lncRNA TERRA. The telomeric enrichment of Exosc9 is cell cycle-dependent and consistent with the loss of telomeric TERRA in the S/G2 phase. Elevated Exosc9 is frequently observed and drives the growth of endocrine therapy-resistant (ET-R) HR+ breast cancer (BCa) cells. Specifically, the knockdown of Exosc9 inversely impacts telomeric R-loops and the integrity of the chromosome ends of ET-R cells. Consistently, Exosc9 levels dictate DNA damage and the sensitivity of ET-R BCa cells to PARP inhibitors. In this regard, Exosc9 may serve as a promising biomarker for predicting the response to PARP inhibitors as a targeted monotherapy for ET-R HR+ BCa. [ABSTRACT FROM AUTHOR]

Diante da importância da terra para a discussão do desenvolvimento, pretendemos entender os desafios de reconhecimento e garantia dos territórios indígenas em um espaço e tempo específico – a Amazônia brasileira durante a Ditadura Militar. Neste período, as terras das populações tradicionais eram vistas como entraves ao progresso e ao desenvolvimento econômico, por isso, o objetivo era “integrar para não entregar”, ou seja, ocupar os territórios amazônicos considerados improdutivos. Algumas das principais consequências foram: 1- comprometimento da manutenção do modo de vida dos povos indígenas; e 2- implicações negativas em relação à multiplicidade cultural e direitos universais. Desse modo, entende-se que o reconhecimento das terras destes povos tradicionais é um direito histórico, representando a manutenção de seus costumes, tradições, organização e cultura de modo geral. É importante ter em mente que a terra confere identidade aos índios, representando um papel social que garante a própria continuidade do meio de vida dessas populações. Sendo assim, este trabalho se justifica pela necessidade de trazer para debate os desafios históricos da governança de terras no que diz respeito aos povos indígenas da Amazônia brasileira.

Este artigo tem como objetivo trazer uma reflexão sobre uma nova perspectiva de direito à cidade, que ressignifique e recomponha a relação entre humanidade e natureza, de modo a contribuir para a superação da atual crise civilizatória. Ele está estruturado em 3 seções. A primeira realiza uma discussão sobre a atual crise civilizatória e sua relação com a cultura da terra hegemônica, fundada na lógica da propriedade privada e da cidade-mercadoria, apontando para a necessidade de se construir alternativas à ela. A segunda parte apresenta culturas da terra contra-hegemônicas que podem trazer uma nova perspectiva à luta por direito à cidade, incorporando as subjetividades da natureza e uma ressignificação da relação entre natureza e humanidade. A terceira apresenta as contribuições de práticas de Agricultura Urbana em Curitiba, apontando avanços em direção ao direito à cidade e à uma nova cultura da terra, mostrando alguns de seus desafios e potencialidades.

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The telomeric repeat‐containing RNA, TERRA, associates with both telomeric DNA and telomeric proteins, often forming RNA:DNA hybrids (R‐loops). TERRA is most abundant in cancer cells utilizing the alternative lengthening of telomeres (ALT) pathway for telomere maintenance, suggesting that persistent TERRA R‐loops may contribute to activation of the ALT mechanism. Therefore, we sought to identify the enzyme(s) that regulate TERRA metabolism in mammalian cells. Here, we identify that the 5′–3′ exoribonuclease XRN2 regulates the stability of TERRA RNA. Moreover, while stabilization of TERRA alone was insufficient to drive ALT, depletion of XRN2 in ALT‐positive cells led to a significant increase in TERRA R‐loops and exacerbated ALT activity. Together, our findings highlight XRN2 as a key determinant of TERRA metabolism and telomere stability in cancer cells that rely on the ALT pathway. [ABSTRACT FROM AUTHOR]

Abstract Background Multiple myeloma (MM) is a hematologic malignancy characterized by high genomic instability, and telomere dysfunction is an important cause of acquired genomic alterations. Telomeric repeat-containing RNA (TERRA) transcripts are long non-coding RNAs involved in telomere stability through the interaction with shelterin complex. Dysregulation of TERRAs has been reported across several cancer types. We recently identified a small molecule, hit 17, which stabilizes the secondary structure of TERRA. In this study, we investigated in vitro and in vivo anti-MM activities of hit 17. Methods Anti-proliferative activity of hit 17 was evaluated in different MM cell lines by cell proliferation assay, and the apoptotic process was analyzed by flow cytometry. Gene and protein expressions were detected by RT-qPCR and western blotting, respectively. Microarray analysis was used to analyze the transcriptome profile. The effect of hit 17 on telomeric structure was evaluated by chromatin immunoprecipitation. Further evaluation in vivo was proceeded upon NCI-H929 and AMO-1 xenograft models. Results TERRA G4 stabilization induced in vitro dissociation of telomeric repeat‐binding factor 2 (TRF2) from telomeres leading to the activation of ATM-dependent DNA damage response, cell cycle arrest, proliferation block, and apoptotic death in MM cell lines. In addition, up-regulation of TERRA transcription was observed upon DNA damage and TRF2 loss. Transcriptome analysis followed by gene set enrichment analysis (GSEA) confirmed the involvement of the above-mentioned processes and other pathways such as E2F, MYC, oxidative phosphorylation, and DNA repair genes as early events following hit 17-induced TERRA stabilization. Moreover, hit 17 exerted anti-tumor activity against MM xenograft models. Conclusion Our findings provide evidence that targeting TERRA by hit 17 could represent a promising strategy for a novel therapeutic approach to MM.

Remote sensing has been studied by many scientists and engineers today. Ground station data are stationary and there is insufficient data in large areas and difficult areas. But satellite data can be used for all regions. In this study, the precipitation data of four synoptic stations in Gamasiab basin are compared with the precipitation data of CHRIPS, ERA5, PERSIAN_CDR, GPM, GSM, TRMM, TERRA satellites. The results show that although CHRIPS satellite had a lower value of false alarm rate and relative deviation in the probabilistic criteria and PERSIAN and GSM have a higher probability of detection, but considering all the criteria, for Harsin and Kangavar stations, TERRA satellite with higher correlation coefficient and Pierce correlation coefficient and the lower the value in the error criteria and the better probability criteria, had the more accurate the estimate. ERA5 satellite also had the best estimate for Sararud and Songhor stations.This satellite has estimated the maximum precipitation at Sararud and Songhor stations, which was 351.7 and 147.9 mm, respectively, with a decrease of 178 and 155 mm by 49 and 5%, respectively.

Our longest, stable record of cloud‐top pressure (CTP) and cloud‐top height (CTH) are derived from the Moderate Resolution Imaging Spectroradiometer (MODIS) and Multi‐Angle Imaging Spectroradiometer (MISR) on Terra. Because of single cloud‐layer assumptions in their standard algorithms, they provide only single CTP/CTH retrievals in multi‐layered situations. In the predominant multi‐layered regime of thin cirrus over low clouds, MODIS significantly overestimates cirrus CTP and emissivity, while MISR accurately retrieves low‐cloud CTH. Utilizing these complementary capabilities, we develop a retrieval algorithm for accurately determining both‐layer CTP and cirrus emissivity for such 2‐layered clouds, by applying the MISR low‐cloud CTH as a boundary condition to a modified MODIS CO2‐slicing retrieval. We evaluate our 2‐layered retrievals against collocated Cloud‐Aerosol Transport System (CATS) lidar observations. Relative to CATS, the mean bias of the upper cloud CTP and emissivity are reduced by ∼90% and ∼75% respectively in the new technique, compared to standard MODIS products. We develop an error model for the 2‐layered retrieval accounting for systematic and random errors. We find up to 87% of all residuals lie within modeled 95% confidence intervals, indicating a near‐closure of error budget. This reduction in error leads to a reduction in modeled atmospheric longwave radiative flux biases ranging between 5 and 40 W m−2, depending on the position and optical properties of the layers. Given this large radiative impact, we recommend that the pixel‐level 2‐layered MODIS + MISR fusion algorithm be applied over the entire MISR swath for the 22‐year Terra record, leading to a first‐of‐its‐kind 2‐layered cloud climatology from Terra's morning orbit. Plain Language Summary: Our longest climate‐quality record of global cloud‐top heights (CTH) comes from the Moderate Resolution Imaging Spectroradiometer (MODIS) and Multi‐Angle Imaging Spectroradiometer (MISR) on the Terra satellite. These sensors assume a single cloud‐layer in retrieving CTH, even though ∼30% of global cloud cover is multi‐layered. Multi‐layered clouds predominantly consist of thin ice clouds over low clouds. Under such conditions, MISR accurately retrieves low‐cloud CTH, while MODIS systematically underestimates upper‐cloud‐layer CTH. Here, we have developed a 2‐layered MODIS + MISR fusion CTH retrieval by using MISR's accurate low‐cloud CTH as an input to a modified MODIS algorithm. This algorithm combines the complementary capabilities of MISR and MODIS in distinguishing higher and lower clouds and estimates both‐layer cloud heights and high‐cloud emissivity. Through comparisons against coincident Cloud‐Aerosol Transport System lidar observations, we find that the new algorithm improves the accuracies in retrieved CTH and cloud emissivities by ∼75% over standard MODIS products. We further demonstrate significant improvements in estimates of simulated atmospheric longwave radiation from our implementation. Owing to its large radiative impact, we suggest that the pixel‐level fusion algorithm be applied to all 22 years of Terra record to facilitate public dissemination of the first 2‐layered cloud record from its morning orbit. Key Points: Accurate, high‐precision Multi‐Angle Imaging Spectroradiometer low cloud heights are employed in a physics‐based correction to Moderate Resolution Imaging Spectroradiometer CO2‐slicing in multi‐layered scenesCloud‐top pressure (CTP) bias drops from 65 to 5 hPa, resulting in a quartering of cloud‐height and emissivity bias for cirrus over low cloudUp to 87% of CTP retrieval errors are bound by theoretical estimates, resulting in near‐closure of CO2‐slicing error budget [ABSTRACT FROM AUTHOR]

Simple Summary: R-loops, also referred to as RNA: DNA hybrids, are tripartite structures formed when a single-stranded RNA molecule forms a complex with a double-stranded DNA duplex via homology-directed base pairing. Many cellular functions are thought to be mediated by R-loops, including gene regulation, DNA replication, chromatin patterning, and DNA repair. R-loops are common and dynamic structures that account for up to 5% of mammalian genomes. In this review, we present an updated review of R-loops at a specific locus, telomeres. We summarize recent advances in the protein factors that regulate the formation and resolution of R-loops at telomeres. We also discuss the role of persistent or unscheduled R-loops in promoting genome and telomere instability and their links to human diseases. Telomeric repeat containing RNA (TERRA) is transcribed from subtelomeric regions to telomeres. TERRA RNA can invade telomeric dsDNA and form telomeric R-loop structures. A growing body of evidence suggests that TERRA-mediated R-loops are critical players in telomere length homeostasis. Here, we will review current knowledge on the regulation of R-loop levels at telomeres. In particular, we will discuss how the central player TERRA and its binding proteins modulate R-loop levels through various mechanisms. We will further provide an overview of the consequences of TERRA-mediated persistent or unscheduled R-loops at telomeres in human ALT cancers and other organisms, with a focus on telomere length regulation after replication interference-induced damage and DNA homologous recombination-mediated repair. [ABSTRACT FROM AUTHOR]

O que este escrito propõe são alguns passos, rumo a um querer-saber. Um saber que enlaça, em um único vôo, artes, ciências e filosofias para, assim, tecer entendimentos sobre um tema em questão: a crise ambiental contemporânea. Neste esforço interdisciplinar, a arte, em especial, o samba, nos alimenta de belíssimas imagens, para então refletir sobre o desencontro e ruptura humano-natureza. Imagens estas gestadas na reunião poética de artistas do samba. Ao nosso ver, de tal rompimento se releva o fundamento da crise em discussão. Aqui, algumas interpretações das artes são apropriadas pelo pensamento ambiental, sendo o último amparado por reflexões geográficas sobre a relação meio e sociedade. O ser humano perdeu a dimensão da terra que há em si mesmo, a partir do momento que se afastou e continua a se afastar da efetividade imanente. Paralelo a esse desterro, o pensamento convencional confortou-se em bases transcendentais, forjadas pelo peso e autoridade do racionalismo. Do otimismo racional fez-se o otimismo da técnica, edificada para submeter a natureza aos seus interesses. É sobre esse caminho que trilhamos, no esforço de compreender e pensar a crise que precisa ser enfrentada em nosso tempo.

The telomeric noncoding RNA TERRA is a key component of telomeres and it is widely expressed in normal as well as cancer cells. In the last 15 years, several publications have shed light on the role of TERRA in telomere homeostasis and cell survival in cancer cells. However, only few studies have investigated the regulation or the functions of TERRA in normal tissues. A better understanding of the biology of TERRA in non-cancer cells may provide unexpected insights into how these lncRNAs are transcribed and operate in cells, and their potential role in physiological processes, such as aging, age-related pathologies, inflammatory processes and human genetic diseases. In this review we aim to discuss the findings that have advanced our understanding of the biology of TERRA using non-cancer mammalian cells as a model system.

O propósito deste artigo é discutir o modo de vida camponês por meio da análise das suas práticas sociais e dos valores que delinearam o fazer-se da vida desta classe social. Para isso, realizou-se um debate sobre o tema a partir do levantamento dos principais apontamentos teóricos sobre esse importante modo de vida tradicional. Importante não só para os próprios camponeses ou para aqueles que os estuda, mas a toda sociedade, pois a recriação contraditória da classe camponesa pela dinâmica do capitalismo interfere diretamente na maneira como os integrantes dessa reproduzem sua vida, suas práticas e seus valores. Além disso, a territorialidade camponesa, pautada na terra, na família e no trabalho é, ao mesmo tempo, a marca e a diferenciação do modo de vida dessa classe em relação aos demais existentes no interior do modo de produção hegemônico.

Em uma perspectiva indígena, a casa não se restringe a um edifício (como construção), que oferece abrigo das intemperes, permitindo que se possa dormir em segurança. Se a casa é lugar da morada, esta deve ser compreendida de maneira ampliada, como a Terra que somos. Não em um sentido genérico, mas na particularidade da experiência ancestral. Para nós, Payayá, a casa é a própria Caatinga. Não moramos na Oka, nela nos abrigamos. Moramos na Caatinga, que nos acolhe ao mesmo tempo em que a acolhemos, respeitosamente. Esse morar expressa o sentido radical da casa como Yby, palavra tupi para Terra. Trata-se do fruir da Caatinga, para além do alimento ou da natureza: é uma escuta, um mútuo pertencimento que implica a radicalidade ética. Neste sentido, o processo de colonização como desbaratamento e desterramento são violências que atingem a morada, não apenas como vilipêndio aos povos indígenas, mas também como desprezo e estigmatização da própria Caatinga. O artigo objetiva discutir este sentido radical da casa como Yby, articulando a reflexão levinasiana da morada com a ancestralidade da experiência catinguense Payayá.

Resumo: O artigo focaliza eventos mortuários atravessados por atos de colonização e, a partir de sua complexidade, explora uma noção etnográfica de catástrofe. Entre os povos indígenas do “Complexo do Marico” (Maldi 1991), a continuidade ontológica entre corpos e lugares revelada pela morte precisa ser modulada por ritos funerários. Esse controle não está imune ao deslocamento forçado, fechamento e depredação territorial impostos pelos não indígenas. Procedo analisando a codificação mitológica entre distância e guerra, o problema da morte e do luto em espaços perturbados, e o efeito dessa perturbação sobre entes sobrenaturais. A conexão entre esses temas revela a inventividade indígena na continuidade da vida, que é interpretada por meio da noção de “catástrofe da sobrenatureza”.

Background: Multiple myeloma (MM) is a hematologic malignancy characterized by high genomic instability, and telomere dysfunction is an important cause of acquired genomic alterations. Telomeric repeat-containing RNA (TERRA) transcripts are long non-coding RNAs involved in telomere stability through the interaction with shelterin complex. Dysregulation of TERRAs has been reported across several cancer types. We recently identified a small molecule, hit 17, which stabilizes the secondary structure of TERRA. In this study, we investigated in vitro and in vivo anti-MM activities of hit 17. Methods: Anti-proliferative activity of hit 17 was evaluated in different MM cell lines by cell proliferation assay, and the apoptotic process was analyzed by flow cytometry. Gene and protein expressions were detected by RT-qPCR and western blotting, respectively. Microarray analysis was used to analyze the transcriptome profile. The effect of hit 17 on telomeric structure was evaluated by chromatin immunoprecipitation. Further evaluation in vivo was proceeded upon NCI-H929 and AMO-1 xenograft models. Results: TERRA G4 stabilization induced in vitro dissociation of telomeric repeat‐binding factor 2 (TRF2) from telomeres leading to the activation of ATM-dependent DNA damage response, cell cycle arrest, proliferation block, and apoptotic death in MM cell lines. In addition, up-regulation of TERRA transcription was observed upon DNA damage and TRF2 loss. Transcriptome analysis followed by gene set enrichment analysis (GSEA) confirmed the involvement of the above-mentioned processes and other pathways such as E2F, MYC, oxidative phosphorylation, and DNA repair genes as early events following hit 17-induced TERRA stabilization. Moreover, hit 17 exerted anti-tumor activity against MM xenograft models. Conclusion: Our findings provide evidence that targeting TERRA by hit 17 could represent a promising strategy for a novel therapeutic approach to MM. [ABSTRACT FROM AUTHOR]

Telomeres are structures made of DNA, proteins and RNA found at the ends of eukaryotic linear chromosomes. These dynamic nucleoprotein structures protect chromosomal tips from end-to-end fusions, degradation, activation of damage checkpoints and erroneous DNA repair events. Telomeres were thought to be transcriptionally silent regions because of their constitutive heterochromatin signature until telomeric long non-coding RNAs (LncRNAs) were discovered. One of them, TERRA (TElomeric Repeat-containing RNA), starts in the subtelomeric regions towards the chromosome ends from different telomeres and has been extensively studied in many evolutionarily distant eukaryotes. Changes in TERRA's expression can lead to telomeric dysfunction, interfere with the replicative machinery and impact telomere length. TERRA also co-localizes in vivo with telomerase, and can form RNA:DNA hybrid structures called R-loops, which have been implicated in the onset of senescence and the alternative lengthening of telomere (ALT) pathway. Yet, the molecular mechanisms involving TERRA, as well as its function, remain elusive. Here, we review the current knowledge of TERRA transcription, structure, expression, regulation and its multiple telomeric and extra-telomeric functions in the budding yeast Saccharomyces cerevisiae. [ABSTRACT FROM AUTHOR]

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Telomere transcription into telomeric repeat-containing RNA (TERRA) is an integral component of all aspects of chromosome end protection consisting of telomerase- or recombination-dependent telomere elongation, telomere capping, and the preservation of the (sub)telomeric heterochromatin structure. The chromatin modifier and transcriptional regulator MLL binds to telomeres and regulates TERRA transcription in telomere length homeostasis and response to telomere dysfunction. MLL fusion proteins (MLL-FPs), the product of MLL rearrangements in leukemia, also bind to telomeric chromatin. However, an effect on telomere transcription in MLL-rearranged (MLL-r) leukemia has not yet been evaluated. Here, we show increased UUAGGG repeat-containing RNA levels in MLL-r acute lymphoblastic leukemia (ALL) when compared to non-MLL-r ALL and myeloid leukemia. MLL rearrangements do not affect telomere length and UUAGGG repeat-containing RNA levels correlate with mean telomere length and reflect increased levels of TERRA. Furthermore, high levels of TERRA in MLL-r ALL occur in the presence of telomerase activity and are independent of ploidy, an underestimated source of variation on the overall transcriptome size in a cell. This MLL rearrangement-dependent and lymphoid lineage-associated increase in levels of TERRA supports a sustained telomere transcription by MLL-FPs that correlates with marked genomic stability previously reported in pediatric MLL-r ALL. [ABSTRACT FROM AUTHOR]

Mammalian telomeres consist of (TTAGGG)n repeats. Transcription of the C-rich strand generates a G-rich RNA, termed TERRA, containing G-quadruplex structures. Recent discoveries in several human nucleotide expansion diseases revealed that RNA transcripts containing long runs of 3 or 6 nt repeats which can form strong secondary structures can be translated in multiple frames to generate homopeptide or dipeptide repeat proteins, and multiple studies have shown them to be toxic in cells. We noted that the translation of TERRA would generate two dipeptide repeat proteins: highly charged repeating valine–arginine (VR)n and hydrophobic repeating glycine–leucine (GL)n. Here, we synthesized these two dipeptide proteins and raised polyclonal antibodies to VR. The VR dipeptide repeat protein binds nucleic acids and localizes strongly to replication forks in DNA. Both VR and GL form long 8-nm filaments with amyloid properties. Using labeled antibodies to VR and laser scanning confocal microscopy, threefold to fourfold more VR was observed in the nuclei of cell lines containing elevated TERRA as contrasted to a primary fibroblast line. Induction of telomere dysfunction via knockdown of TRF2 led to higher amounts of VR, and alteration of TERRA levels using a locked nucleic acid (LNA) GapmeR led to large nuclear VR aggregates. These observations suggest that telomeres, in particular in cells undergoing telomere dysfunction, may express two dipeptide repeat proteins with potentially strong biological properties. [ABSTRACT FROM AUTHOR]

During the last half century, the Catalan rural world has been transformed by a series of processes -- industrialization, urbanization, consolidation of an economy linked to leisure, rural exodus, crisis of family agriculture -- that have left a deep footprint both in its territory and in the consciousness of its inhabitants. Inspired by the work of Ann Laura Stoler and Gastón Gordillo on ruination and rubble, and based on several recent ethnographic works, this article looks for the traces of dislocation that these economic transformations have left in the landscape of the High Pyrenees and Terra Alta. The purpose of this exercise is twofold. On the one hand, to question the triumphant temporality embodied in the narratives of modernization and economic growth. On the other hand, to investigate how these traces speak of the survival of ways of life and ways of conceiving nature and territory -- what I call "cultural models" -- linked to a peasant-based agricultural economy. [ABSTRACT FROM AUTHOR]

Telomeres are terminal structures that define the ends of linear chromosomes. They harbour specialized ribonucleoprotein complexes which play a major role in genome integrity by preventing unscheduled DNA damage repair events. Genes located adjacent to telomere repeat sequences are repressed by a phenomenon called telomere position effect (TPE) via epigenetic silencing. RNA surveillance pathways post-transcriptionally regulate any leaky transcripts arising from the telomeres. Recently, multiple non-coding RNA species originate from telomere ends, namely, TERRA (telomeric repeat‐containing RNA), ARRET, sub-telomeric XUTs and sub-telomeric CUTs have been identified. In this study, we report a role for the transcription termination complex (Rtt103-Rai1-Rat1) in regulating the abundance of the sub-telomeric transcripts in a transcription-dependent manner. We show that the Rtt103 mutants have elevated levels of TERRA and other sub-telomeric transcripts that are usually silenced. Our study suggests that Rtt103 potentially recruits the exonuclease, Rat1 in a RNA polymerase II dependent manner to degrade these transcripts and regulate their levels in the cell. [ABSTRACT FROM AUTHOR]

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