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Nuclear pore proteins control nucleocytoplasmic transport; however, certain nucleoporins play regulatory roles in activities such as transcription and chromatin organization. The fission yeast basket nucleoporin Nup211 is implicated in mRNA export and is essential for cell viability. Nup211 preferentially associates with heterochromatin, however, it is unclear whether it plays a role in regulating transcription. To better understand its functions, we constructed a nup211 "shut-off" strain and observed that Nup211 depletion led to severe defects in cell cycle progression, including septation and cytokinesis. Using RNA-Seq and RT-qPCR, we revealed that loss of Nup211 significantly altered the mRNA levels of a set of genes crucial for cell division. Using domain analysis and CRISPR/cas9 technology, we determined that the first 655 residues of Nup211 are sufficient for viability. This truncated protein was detected at the nuclear periphery. Furthermore, exogenous expression of this domain in nup211 shut-off cells effectively restored both cell morphology and transcript abundance for some selected genes. Our findings unveil a novel role for Nup211 in regulating gene expression.

Nuclear pore proteins control nucleocytoplasmic transport; however, certain nucleoporins play regulatory roles in activities such as transcription and chromatin organization. The fission yeast basket nucleoporin Nup211 is implicated in mRNA export and is essential for cell viability. Nup211 preferentially associates with heterochromatin, however, it is unclear whether it plays a role in regulating transcription. To better understand its functions, we constructed a nup211 "shut-off" strain and observed that Nup211 depletion led to severe defects in cell cycle progression, including septation and cytokinesis. Using RNA-Seq and RT-qPCR, we revealed that loss of Nup211 significantly altered the mRNA levels of a set of genes crucial for cell division. Using domain analysis and CRISPR/cas9 technology, we determined that the first 655 residues of Nup211 are sufficient for viability. This truncated protein was detected at the nuclear periphery. Furthermore, exogenous expression of this domain in nup211 shut-off cells effectively restored both cell morphology and transcript abundance for some selected genes. Our findings unveil a novel role for Nup211 in regulating gene expression. [ABSTRACT FROM AUTHOR]

Abstract Background LINE-1 (L1) is the dominant autonomously replicating non-LTR retrotransposon in mammals. Although our knowledge of L1 evolution across the tree of life has considerably improved in recent years, what we know of L1 evolution in mammals is biased and comes mostly from studies in primates (mostly human) and rodents (mostly mouse). It is unclear if patterns of evolution that are shared between those two groups apply to other mammalian orders. Here we performed a detailed study on the evolution of L1 in perissodactyls by making use of the complete genome of the domestic horse and of the white rhinoceros. This mammalian order offers an excellent model to study the extinction of L1 since the rhinoceros is one of the few mammalian species to have lost active L1. Results We found that multiple L1 lineages, carrying different 5’UTRs, have been simultaneously active during the evolution of perissodactyls. We also found that L1 has continuously amplified and diversified in horse. In rhinoceros, L1 was very prolific early on. Two successful families were simultaneously active until ~20my ago but became extinct suddenly at exactly the same time. Conclusions The general pattern of L1 evolution in perissodactyls is very similar to what was previously described in mouse and human, suggesting some commonalities in the way mammalian genomes interact with L1. We confirmed the extinction of L1 in rhinoceros and we discuss several possible mechanisms.

Objective: There has been little inquiry addressing whether or not concerns about adverse effects of energy drink usage are relevant in the Caribbean. This survey investigated energy drink usage and adverse consequences among tertiary level students in Trinidad and Tobago. Methods: A cross-sectional survey of 1994 students from eight institutions was conducted using a de novo questionnaire based on findings from a focus group of students. Chi-squared analyses and logistic regression were used to assess relationships between energy drink usage, adverse effects and other factors affecting energy drink use, and to verify predictors of energy drink use. Results: Prevalence of use was 86%; 38% were current users. Males were more likely to use, used more frequently and at an earlier age. Energy drinks were used most commonly to increase energy (50%), combat sleepiness (45%) and enhance academic performance (40%), and occurred during sports (23%) and mixed with alcohol (22.2%). The majority (79.6%) consumed one energy drink per sitting; 62.2% experienced adverse effects, most commonly restlessness (22%), jolt and crash (17.1%) and tachycardia (16.6%). Awareness of adverse effects was associated with no use (p = 0.004), but adverse effects were not a deterrent to continued use. Conclusion: Energy drink usage is prevalent among students. The use is not excessive, but associated with high rates of adverse effects and occurs in potentially dangerous situations like during exercise and with alcohol. There is a need to educate students about the potential adverse effects of energy drinks.

This article aims to demonstrate that work study techniques must be used to determine standard times for operations and to develop efficiency reporting systems to sustain organisations. Many organisations do not measure their efficiencies and do not have reporting systems. This article presents an efficiency reporting system designed and based on work study techniques that can be used to measure performance. The empirical results of the research instrument supported the need for the system. The existence of a dedicated efficiency reporting system ensures that employee performance and outputs in line with set targets are measured and sustained.