Alternative splicing (AS) enables differential inclusion of exons from a given transcript, thereby contributing to the transcriptome and proteome diversity. Aberrant AS patterns play major roles in ...the development of different pathologies, including breast cancer. N
-methyladenosine (m
A), the most abundant internal modification of eukaryotic mRNA, influences tumor progression and metastasis of breast cancer, and it has been recently linked to AS regulation. Here, we identify a specific AS signature associated with breast tumorigenesis in vitro. We characterize for the first time the role of METTL3 in modulating breast cancer-associated AS programs, expanding the role of the m
A-methyltransferase in tumorigenesis. Specifically, we find that both m
A deposition in splice site boundaries and in splicing and transcription factor transcripts, such as MYC, direct AS switches of specific breast cancer-associated transcripts. Finally, we show that five of the AS events validated in vitro are associated with a poor overall survival rate for patients with breast cancer, suggesting the use of these AS events as a novel potential prognostic biomarker.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Planar cell polarity (PCP) is cellular polarity within the plane of an epithelial tissue or organ. PCP is established through interactions of the core Frizzled (Fz)/PCP factors and, although their ...molecular interactions are beginning to be understood, the upstream input providing the directional bias and polarity axis remains unknown. Among core PCP genes, Fz is unique as it regulates PCP both cell-autonomously and non-autonomously, with its extracellular domain acting as a ligand for Van Gogh (Vang). We demonstrate in Drosophila melanogaster wings that Wg (Wingless) and dWnt4 (Drosophila Wnt homologue) provide instructive regulatory input for PCP axis determination, establishing polarity axes along their graded distribution and perpendicular to their expression domain borders. Loss-of-function studies reveal that Wg and dWnt4 act redundantly in PCP determination. They affect PCP by modulating the intercellular interaction between Fz and Vang, which is thought to be a key step in setting up initial polarity, thus providing directionality to the PCP process.
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DOBA, IJS, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
Coronavirus disease 2019 (COVID-19) has become a global pandemic with serious consequences that have led to the implementation of unprecedented social isolation measures. At the early stages of the ...pandemic, Ecuador was one of the most affected countries in Latin America. The objective of this study was to assess the levels of depression, anxiety and stress in the Ecuadorian general population during the social isolation period due to COVID-19.
A web-based survey consisting of 31 short-answer and multiple-choice questions was administered to the general population from April 22-May 3, 2020. Mental health status was assessed through the Depression, Anxiety and Stress Scale-21 Items (DASS-21) questionnaire. Ordinal logistic analyses were used to identify potential risk factors associated with the severity of mental health issues.
A total of 626 individuals were included. Most of them were females (60.5%), and their mean age was 29.6 ± 11.7 years. Approximately 17.7% of the respondents had moderate to very severe levels of depression, 30.7% had similar levels of anxiety, and 14.2% experienced stress. Female sex, younger age, student status, and having a relative diagnosed with COVID-19 were associated with significantly higher levels of depression, anxiety and stress. Ordinal regression models showed that being a student was a risk factor for having more severe levels of depression (OR = 3.67; 95% CI = 2.56-5.26, p: 0.0001), anxiety (OR= 1.86; 95% CI= 1.35-2.55, p: 0.0001), and stress (OR = 2.17; 95% CI= 1.47-3.19, p: 0.0001). Having a relative with COVID-19 was also found to be a risk factor only for depression (OR= 1.70; 95% CI= 1.03-2.80, p: 0.036) and anxiety (OR = 2.17; 95% CI= 1.35-3.47, p: 0.001). Additionally, male sex, older age, and having more children were found to be protective factors for the three conditions.
Our findings suggest that social isolation due to the COVID-19 outbreak has impacted the mental health of the general population in Ecuador. We identified potential risk and protective factors that could serve as a foundation from which to develop psychological strategies to safeguard the mental health of our population during the current pandemic.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Wastewater surveillance represents an alternative approach to regulating contamination and the early detection of infectious agents and outbreaks of diseases of public health importance. This study ...evaluated domestic wastewater effects on recreational waters in estuarine and seawater bodies in Guayas and Santa Elena provinces in Ecuador, South America. Fecal indicator bacteria (thermotolerant coliforms) served as key indicators for evaluation. Physical, chemical, and microbiological quality markers following the Ecuadorian environmental quality standard and the discharge of effluents to the water resource were analyzed. Samples were collected from 44 coastal sites and 2 oxidation lagoons during the dry and rainy seasons of 2020 and 2021, respectively. SARS-CoV-2 RNA was detected in samples with higher E. coli concentrations using reverse transcription quantitative PCR to detect the genes N and ORF1ab. All samples analyzed for SARS-CoV-2 showed Ct ˂ 40 for at least one gene. Four samples showed at least 20 genome copies of gene N per reaction. These were at an artisanal fishing port, an estuarine area (Palmar), a recreational bay, and an oxidation lagoon. A moderate correlation was found between SARS-CoV-2 RNA, thermotolerant coliform and E. coli (p-value ≤ 0.0037), and a strong and positive correlation between thermotolerant coliform and E. coli. (p-value ≤ 0.00001), highlighting the utility of these established parameters as a proxy of the virus. Significant differences were found in the concentrations of thermotolerant coliforms between seasons (p-value = 0.016) and sites (p-value = 0.005). The highest levels of coliforms were found in the dry season (63000 MPN/100 mL) in Anconcito and during the rainy season (14000 MPN/100 mL) at Esterillo in Playas County. It is recommended that the decentralized autonomous governments of the surveyed provinces in Ecuador implement urgent corrective actions and establish medium-term mechanisms to minimize a potential contamination route. Additional parameters must be included in the monitoring, such as Enterococcus and intestinal parasites, due to their public health implications. In the oxidation lagoons, maintenance actions must be carried out, including the dissolution of sediments, an increase in water retention times, and in situ treatment of the sludge, to improve the system's performance.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Abstract
The Apache Point Observatory Galactic Evolution Experiment 2 (APOGEE-2) is a dual-hemisphere, near-infrared (NIR), spectroscopic survey with the goal of producing a chemodynamical mapping of ...the Milky Way. The targeting for APOGEE-2 is complex and has evolved with time. In this paper, we present the updates and additions to the initial targeting strategy for APOGEE-2N presented in Zasowski et al. (2017). These modifications come in two implementation modes: (i) “Ancillary Science Programs” competitively awarded to Sloan Digital Sky Survey IV PIs through proposal calls in 2015 and 2017 for the pursuit of new scientific avenues outside the main survey, and (ii) an effective 1.5 yr expansion of the survey, known as the Bright Time Extension (BTX), made possible through accrued efficiency gains over the first years of the APOGEE-2N project. For the 23 distinct ancillary programs, we provide descriptions of the scientific aims, target selection, and how to identify these targets within the APOGEE-2 sample. The BTX permitted changes to the main survey strategy, the inclusion of new programs in response to scientific discoveries or to exploit major new data sets not available at the outset of the survey design, and expansions of existing programs to enhance their scientific success and reach. After describing the motivations, implementation, and assessment of these programs, we also leave a summary of lessons learned from nearly a decade of APOGEE-1 and APOGEE-2 survey operations. A companion paper, F. Santana et al. (submitted; AAS29036), provides a complementary presentation of targeting modifications relevant to APOGEE-2 operations in the Southern Hemisphere.
The paper analyses the literature related to the underrepresentation of women in the scientific field to identify the factors that affect this underrepresentation worldwide. This literature review ...covers 470 papers—published in journals with the highest impact factor from 1985 to 2018—that address the factors that influence the access, participation, and progress of women in scientific careers. This literature review was based on the complete readings of the papers using thematic analysis. The factors that influence women’s access, participation and progress in careers related to science and technology are a complex problem with multiple interdependent factors. In addition, these vary according to the stages of women’s lives and cultural contexts. This paper proposes, based on the literature review, a comprehensive framework to explain the factors that influence the access, participation, and progress of women in science careers. The factors are grouped as follows: (a) individual, (b) family, (c) social, (d) educational, and (e) labor-economic. The proposed research is useful for researchers and policy makers because it introduces this phenomenon schematically and orderly identifies the gaps in past research studies, and evidences the need to conduct further research on this topic.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Abstract
We present a large-scale study of stellar rotation for T Tauri stars in the Orion star-forming complex. We use the projected rotational velocity (
v
sin
(
i
)
) estimations reported by the ...APOGEE-2 collaboration as well as individual masses and ages derived from the position of the stars in the HR diagram, considering Gaia-EDR3 parallaxes and photometry plus diverse evolutionary models. We find an empirical trend for
v
sin
(
i
)
decreasing with age for low-mass stars (0.4
M
⊙
<
M
*
< 1.2
M
⊙
). Our results support the existence of a mechanism linking
v
sin
(
i
)
to the presence of accreting protoplanetary disks, responsible for regulating stellar rotation on timescales of about 6 Myr, which is the timescale in which most of the T Tauri stars lose their inner disk. Our results provide important constraints to models of rotation in the early phases of evolution of young stars and their disks.
We developed a grid of stellar rotation models for low-mass and solar-type classical T Tauri stars (CTTS; 0.3M⊙ < M* < 1.2M⊙). These models incorporate the star–disk interaction and magnetospheric ...ejections to investigate the evolution of the stellar rotation rate as a function of the mass of the star M*, the magnetic field (B*), and stellar wind (Ṁwind). We compiled and determined stellar parameters for 208 CTTS, such as projected rotational velocity vsin(i), mass accretion rate Ṁacc, stellar mass M*, ages, and estimated rotational periods using Transiting Exoplanet Survey Satellite (TESS) data. We also estimated a representative value of the mass-loss rate for our sample using the O i λ 6300 spectral line. Our results confirm that vsin(i) measurements in CTTS agree with the rotation rates provided by our spin models in the accretion-powered stellar winds picture. In addition, we used the approximate Bayesian computation technique to explore the connection between the model parameters and the observational properties of CTTS. We find that the evolution of vsin(i) with age might be regulated by variations in (1) the intensity of B* and (2) the fraction of the accretion flow ejected in magnetic winds, removing angular momentum from these systems. The youngest stars in our sample (∼1 Myr) show a median branching ratio Ṁwind/Ṁacc∼0.16 and median B* ∼ 2000 G, in contrast to ∼0.01 and 1000 G, respectively, for stars with ages ≳3 Myr.
Planar cell polarity (PCP) signalling is a well-conserved developmental pathway regulating cellular orientation during development. An evolutionarily conserved pathway readout is not established and, ...moreover, it is thought that PCP mediated cellular responses are tissue-specific. A key PCP function in vertebrates is to regulate coordinated centriole/cilia positioning, a function that has not been associated with PCP in Drosophila. Here we report instructive input of Frizzled-PCP (Fz/PCP) signalling into polarized centriole positioning in Drosophila wings. We show that centrioles are polarized in pupal wing cells as a readout of PCP signalling, with both gain and loss-of-function Fz/PCP signalling affecting centriole polarization. Importantly, loss or gain of centrioles does not affect Fz/PCP establishment, implicating centriolar positioning as a conserved PCP-readout, likely downstream of PCP-regulated actin polymerization. Together with vertebrate data, these results suggest a unifying model of centriole/cilia positioning as a common downstream effect of PCP signalling from flies to mammals.
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