Educator Recruitment In International Schools: The Administrator’s View

In this study, the researcher examined the strategies and tactics that international school leaders use when engaging in the recruitment of international school educators. The study included 89 international school leaders who took part in an online survey regarding various aspects of the recruiting process and 20 international school leaders who took part in a Skype interview to discuss further the process of recruitment. Qualitative inductive content analysis was used to code and theme the data that resulted from the anonymous online surveys and Skype interviews. Five main themes emerged from the data, and these themes described crucial components of recruiting international educators. The first theme, adaptation, describes the way in which school leaders have had to adjust their recruiting in the short and long terms. The second theme, fit versus match, describes the way in which school leaders approach people and positions that are available in their respective schools. The third theme, success, describes the ways in which school leaders define their success, and the measures they use to gauge it. The fourth theme, location and capabilities, shows how strategies and approaches change because of their respective school location and the limitations that might be attached to it. The fifth theme, timelines, describes how recruiting international educators changes depending on when a school leader begins conducting his or her recruitment process. This researcher found that participants perceived as important in the recruiting process many of the recruiting strategies mentioned in the survey. However, their ability to use some of the specific strategies was limited by the country in which they were located and their respective recruiting season. The factors identified in this study build on previous research on international educator recruitment and provides an additional dimension for school leaders to analyze their recruiting efforts and strategies. Further research on how school leaders interpret these factors and on other components of the international teacher recruiting process are important to augment the research in this field

Stem Cell RNA Epigenetics: M6Arking Your Territory

Modifications of mRNAs can have a profound effect on cellular function and differentiation. In this issue of Cell Stem Cell, Batista et al. (2014) describe fundamental parameters of N6-methyl-adenosine modification of mRNAs in embryonic stem cells and provide strong evidence that modification plays a role in exit from pluripotency toward differentiation

A noncoding RNA produced by arthropod-borne flaviviruses inhibits the cellular exoribonuclease XRN1 and alters host mRNA stability

All arthropod-borne flaviviruses generate a short noncoding RNA (sfRNA) from the viral 3′ untranslated region during infection due to stalling of the cellular 5′-to-3′ exonuclease XRN1. We show here that formation of sfRNA also inhibits XRN1 activity. Cells infected with Dengue or Kunjin viruses accumulate uncapped mRNAs, decay intermediates normally targeted by XRN1. XRN1 repression also resulted in the increased overall stability of cellular mRNAs in flavivirus-infected cells. Importantly, a mutant Kunjin virus that cannot form sfRNA but replicates to normal levels failed to affect host mRNA stability or XRN1 activity. Expression of sfRNA in the absence of viral infection demonstrated that sfRNA formation was directly responsible for the stabilization of cellular mRNAs. Finally, numerous cellular mRNAs were differentially expressed in an sfRNA-dependent fashion in a Kunjin virus infection. We conclude that flaviviruses incapacitate XRN1 during infection and dysregulate host mRNA stability as a result of sfRNA formation

The relationship between the prothrombin upstream sequence element and the G20210A polymorphism: the influence of a competitive environment for mRNA 3′-end formation

The human prothrombin G20210A polymorphism located at the 3′ cleavage site of the mRNA results in elevated plasma prothrombin levels and increased risk of venous thrombosis. This polymorphism has been shown to directly influence a variety of processes related to prothrombin mRNA metabolism. We have constructed plasmids that express the full-length prothrombin mRNA that is polyadenylated at its natural site. The A allele prothrombin variant was more efficient than the G allele at promoting cleavage at this site in the presence of a competing poly (A) sequence. In the absence of competition, both allelic variants give rise to a similar level of cleavage site heterogeneity. An upstream sequence element (USE) was also identified within the prothrombin 3′-UTR. When placed upstream of two competing poly (A) sites, the USE directed cleavage preferentially to the proximal poly (A) site. In the absence of competition, the USE had no effect on cleavage site selection. This study suggests that the basis for the increase in prothrombin expression in A allele carriers is not due to allelic changes in cleavage site selection per se. In addition, the functionality of USEs needs to be considered within the context of endogenous sequence architecture

Serum-deprivation stimulates cap-binding by PARN at the expense of eIF4E, consistent with the observed decrease in mRNA stability

PARN, a poly(A)-specific ribonuclease, binds the 5′ cap-structure of mRNA and initiates deadenylation-dependent decay. Eukaryotic initiation factor 4E (eIF4E) also binds to the cap structure, an interaction that is critical for initiating cap-dependent translation. The stability of various mRNA transcripts in human cell lines is reduced under conditions of serum starvation as determined by both functional and chemical half-lives. Serum starvation also leads to enhanced cap association by PARN. In contrast, the 5′ cap occupancy by eIF4E decreases under serum-deprivation, as does the translation of reporter transcripts. Further, we show that PARN is a phosphoprotein and that this modification can be modulated by serum status. Taken together, these data are consistent with a natural competition existing at the 5′ cap structure between PARN and eIF4E that may be regulated by changes in post-translational modifications. These phosphorylation-induced changes in the interplay of PARN and eIF4E may determine whether the mRNA is translated or decayed

Aedes aegypti uses RNA interference in defense against Sindbis virus infection

<p>Abstract</p> <p>Background</p> <p>RNA interference (RNAi) is an important anti-viral defense mechanism. The <it>Aedes aegypti </it>genome encodes RNAi component orthologs, however, most populations of this mosquito are readily infected by, and subsequently transmit flaviviruses and alphaviruses. The goal of this study was to use <it>Ae. aegypti </it>as a model system to determine how the mosquito's anti-viral RNAi pathway interacts with recombinant Sindbis virus (SINV; family <it>Togaviridae</it>, genus <it>Alphavirus</it>).</p> <p>Results</p> <p>SINV (TR339-eGFP) (+) strand RNA, infectious virus titers and infection rates transiently increased in mosquitoes following dsRNA injection to cognate <it>Ago2</it>, <it>Dcr2</it>, or <it>TSN </it>mRNAs. Detection of SINV RNA-derived small RNAs at 2 and 7 days post-infection in non-silenced mosquitoes provided important confirmation of RNAi pathway activity. Two different recombinant SINV viruses (MRE16-eGFP and TR339-eGFP) with significant differences in infection kinetics were used to delineate vector/virus interactions in the midgut. We show virus-dependent effects on RNAi component transcript and protein levels during infection. Monitoring midgut <it>Ago2</it>, <it>Dcr2</it>, and <it>TSN </it>transcript levels during infection revealed that only <it>TSN </it>transcripts were significantly increased in midguts over blood-fed controls. Ago2 protein levels were depleted immediately following a non-infectious bloodmeal and varied during SINV infection in a virus-dependent manner.</p> <p>Conclusion</p> <p>We show that silencing RNAi components in <it>Ae. aegypti </it>results in transient increases in SINV replication. Furthermore, <it>Ae. aegypti </it>RNAi is active during SINV infection as indicated by production of virus-specific siRNAs. Lastly, the RNAi response varies in a virus-dependent manner. These data define important features of RNAi anti-viral defense in <it>Ae. aegypti</it>.</p

The 3′ Untranslated Region of the Rabies Virus Glycoprotein mRNA Specifically Interacts with Cellular PCBP2 Protein and Promotes Transcript Stability

Viral polymerase entry and pausing at intergenic junctions is predicted to lead to a defined polarity in the levels of rhabdovirus gene expression. Interestingly, we observed that the rabies virus glycoprotein mRNA is differentially over-expressed based on this model relative to other transcripts during infection of 293T cells. During infection, the rabies virus glycoprotein mRNA also selectively interacts with the cellular poly(rC)-binding protein 2 (PCBP2), a factor known to influence mRNA stability. Reporter assays performed both in electroporated cells and in a cell-free RNA decay system indicate that the conserved portion of the 3′ UTR of the rabies virus glycoprotein mRNA contains an RNA stability element. PCBP2 specifically interacts with reporter transcripts containing this 72 base 3′ UTR sequence. Furthermore, the PCBP2 interaction is directly associated with the stability of reporter transcripts. Therefore, we conclude that PCBP2 specifically and selectively interacts with the rabies virus glycoprotein mRNA and that this interaction may contribute to the post-transcriptional regulation of glycoprotein expression

Systematic Analysis of Cis-Elements in Unstable mRNAs Demonstrates that CUGBP1 Is a Key Regulator of mRNA Decay in Muscle Cells

BACKGROUND: Dramatic changes in gene expression occur in response to extracellular stimuli and during differentiation. Although transcriptional effects are important, alterations in mRNA decay also play a major role in achieving rapid and massive changes in mRNA abundance. Moreover, just as transcription factor activity varies between different cell types, the factors influencing mRNA decay are also cell-type specific. PRINCIPAL FINDINGS: We have established the rates of decay for over 7000 transcripts expressed in mouse C2C12 myoblasts. We found that GU-rich (GRE) and AU-rich (ARE) elements are over-represented in the 3'UTRs of short-lived mRNAs and that these mRNAs tend to encode factors involved in cell cycle and transcription regulation. Stabilizing elements were also identified. By comparing mRNA decay rates in C2C12 cells with those previously measured for pluripotent and differentiating embryonic stem (ES) cells, we identified several groups of transcripts that exhibit cell-type specific decay rates. Further, whereas in C2C12 cells the impact of GREs on mRNA decay appears to be greater than that of AREs, AREs are more significant in ES cells, supporting the idea that cis elements make a cell-specific contribution to mRNA stability. GREs are recognized by CUGBP1, an RNA-binding protein and instability factor whose function is affected in several neuromuscular diseases. We therefore utilized RNA immunoprecipitation followed by microarray (RIP-Chip) to identify CUGBP1-associated transcripts. These mRNAs also showed dramatic enrichment of GREs in their 3'UTRs and encode proteins linked with cell cycle, and intracellular transport. Interestingly several CUGBP1 substrate mRNAs, including those encoding the myogenic transcription factors Myod1 and Myog, are also bound by the stabilizing factor HuR in C2C12 cells. Finally, we show that several CUGBP1-associated mRNAs containing 3'UTR GREs, including Myod1, are stabilized in cells depleted of CUGBP1, consistent with the role of CUGBP1 as a destabilizing factor. CONCLUSIONS: Taken together, our results systematically establish cis-acting determinants of mRNA decay rates in C2C12 myoblast cells and demonstrate that CUGBP1 associates with GREs to regulate decay of a wide range of mRNAs including several that are critical for muscle development