Erythroid Kruppel-like factor directly activates the basic Kruppel-like factor gene in erythroid cells

The Sp/Kriippel-like factor (Sp/KIf) family is comprised of around 25 zinc finger transcription factors that recognize CACCC boxes and GC-rich elements. We have investigated basic Kruppel-like factor (Bklf/Klf3) and show that in erythroid tissues its expression is highly dependent on another family member, erythroid Kruppel-like factor (Eklf/Kif1). We observe that Bklf mRNA is significantly reduced in erythroid tissues from Eklf-null murine embryos. We find that Bklf is driven primarily by two promoters, a ubiquitously active GC-rich upstream promoter, la, and an erythroid downstream promoter, 1b. Transcripts from the two promoters encode identical proteins. Interestingly, both the ubiquitous and the erythroid promoter are dependent on Eklf in erythroid cells. Eklf also activates both promoters in transient assays. Experiments utilizing an inducible form of Eklf demonstrate activation of the endogenous Bklf gene in the presence of an inhibitor of protein synthesis. The kinetics of activation are also consistent with Bklf being a direct Eklf target. Chromatin immunoprecipitation assays confirm that Eklf associates with both Bklf promoters. Eklf is typically an activator of transcription, whereas Bklf is noted as a repressor. Our results support the hypothesis that feedback cross-regulation occurs within the Sp/Klf family in vivo

Diel Variations in Survey Catch Rates and Survey Catchability of Spiny Dogfish and their Pelagic Prey in the Northeast US Continental Shelf Large Marine Ecosystem

This study examines the potential uncertainty in survey biomass estimates of Spiny Dogfish Squalus acanthias in the Northeast U.S. Continental Shelf Large Marine Ecosystem (NES LME). Diel catch-per-unit-effort (CPUE) estimates are examined from the Northeast Fisheries Science Center bottom trawl surveys conducted during autumn (1963-2009) and spring (1968-2009). Influential environmental variables on survey catchability are identified for Spiny Dogfish life history stages and five pelagic prey species: Butterfish Peprilus triacanthus, Atlantic Herring Clupea harengus, shortfin squid Illex spp., longfin squid Doryteuthis spp., and Atlantic Mackerel Scomber scombrus. Daytime survey catchability was significantly higher than nighttime catchability for most species during autumn and for mature male Spiny Dogfish, shortfin squid, and longfin squid during spring in the NES LME. For most stages and species examined, breakpoint analyses identified significant increases in CPUE in the morning, peak CPUE during the day, and significant declines in CPUE in the late afternoon. Seasonal probabilities of daytime catch were largely driven by solar zenith angle for most species, with stronger trends identified during autumn. Unadjusted CPUE estimates appear to overestimate absolute abundance, with adjustments resulting in reductions in absolute abundance ranging from 41% for Spiny Dogfish to 91% for shortfin and longfin squids. These findings have important implications for Spiny Dogfish regarding estimates of population consumption of key pelagic prey species and their ecological footprint within the NES LME

A critical review of smaller state diplomacy

In The Peloponnesian War, Thucydides (1972: 402) highlights the effects of the general, overall weakness of smaller states vis-à-vis larger, more powerful ones in a key passage, where the Athenians remind the Melians that: “… since you know as well as we do that, as the world goes, right is only in question between equals in power. Meanwhile, the strong do what they can and the weak suffer what they must.” Concerns about the vulnerability of small, weak, isolated states have echoed throughout history: from Thucydides, through the review by Machiavelli (1985) of the risks of inviting great powers to intervene in domestic affairs, through 20th century US-led contemporary political science (Vital, 1971; Handel, 1990) and Commonwealth led scholarship (Commonwealth Secretariat, 1985). In the context of 20th century ‘Balkanization’, the small state could also prove unstable, even hostile and uncooperative, a situation tempting enough to invite the intrusion of more powerful neighbours: a combination, according to Brzezinski (1997: 123-124) of a power vacuum and a corollary power suction2: in the outcome, if the small state is ‘absorbed’, it would be its fault, and its destiny, in the grand scheme of things. In an excellent review of small states in the context of the global politics of development, Payne (2004: 623, 634) concludes that “vulnerabilities rather than opportunities are the most striking consequence of smallness”. It has been recently claimed that, since they cannot defend or represent themselves adequately, small states “lack real independence, which makes them suboptimal participants in the international system” (Hagalin, 2005: 1). There is however, a less notable and acknowledged but more extraordinary strand of argumentation that considers ‘the power of powerlessness’, and the ability of small states to exploit their smaller size in a variety of ways in order to achieve their intended, even if unlikely, policy outcomes. The pursuance of smaller state goals becomes paradoxically acceptable and achievable precisely because such smaller states do not have the power to leverage disputants or pursue their own agenda. A case in point concerns the smallest state of all, the Vatican, whose powers are both unique and ambiguous, but certainly not insignificant (The Economist, 2007). Smaller states have “punched above their weight” (e.g. Edis, 1991); and, intermittently, political scientists confront their “amazing intractability” (e.g. Suhrke, 1973: 508). Henry Kissinger (1982: 172) referred to this stance, with obvious contempt, as “the tyranny of the weak”3. This paper seeks a safe passage through these two, equally reductionist, propositions. It deliberately focuses first on a comparative case analysis of two, distinct ‘small state-big state’ contests drawn from the 1970s, seeking to infer and tease out the conditions that enable smaller ‘Lilliputian’ states (whether often or rarely) to beat their respective Goliaths. The discussion is then taken forward to examine whether similar tactics can work in relation to contemporary concerns with environmental vulnerability, with a focus on two other, small island states. Before that, the semiotics of ‘the small state’ need to be explored, since they are suggestive of the perceptions and expectations that are harboured by decision makers at home and abroad and which tend towards the self-fulfilling prophecy.peer-reviewe

A Large Gene Network in Immature Erythroid Cells Is Controlled by the Myeloid and B Cell Transcriptional Regulator PU.1

PU.1 is a hematopoietic transcription factor that is required for the development of myeloid and B cells. PU.1 is also expressed in erythroid progenitors, where it blocks erythroid differentiation by binding to and inhibiting the main erythroid promoting factor, GATA-1. However, other mechanisms by which PU.1 affects the fate of erythroid progenitors have not been thoroughly explored. Here, we used ChIP-Seq analysis for PU.1 and gene expression profiling in erythroid cells to show that PU.1 regulates an extensive network of genes that constitute major pathways for controlling growth and survival of immature erythroid cells. By analyzing fetal liver erythroid progenitors from mice with low PU.1 expression, we also show that the earliest erythroid committed cells are dramatically reduced in vivo. Furthermore, we find that PU.1 also regulates many of the same genes and pathways in other blood cells, leading us to propose that PU.1 is a multifaceted factor with overlapping, as well as distinct, functions in several hematopoietic lineages

Erythroid Kruppel-Like factor regulates E2F4 and the G1 Cdk inhibitor, p18

Erythroid Kruppel-Like Factor (EKLF) is a zinc finger transcription factor which is essential for ß-globin gene expression. Knockout mice die from anemia at E15, but restoration of globin chain imbalance does not rescue anemia or increase survival. Cell lines derived from EKLF null mice undergo proliferation arrest upon reactivation of a conditional EKLF-ER fusion protein, suggesting a role in cell cycle control. A transcriptional profiling experiment comparing the global gene expression in EKLF null and wild type fetal liver identified many differentially expressed genes, a number of which function in G1 and at the G1/S checkpoint of the cell cycle. The Cyclin dependent kinase (Cdk) inhibitor, p18, and the S phase transcription factor E2F4 were both found to be significantly down regulated in EKLF null mice and this result was confirmed by real-time PCR. Interestingly, E2F4 knockout mice have a similar phenotype to EKLF knockout mice. Bioinformatic searches of the p18 and E2F4 genes shows that each contains phylogenetically conserved CACC box motifs capable of binding EKLF within longer regions of conservation in promoter and intron regions. The p18 gene contains two conserved CACCC sites upstream of the start of transcription, which are required for EKLF dependent promoter activity in luciferase reporter assays. The transcription factor E2F4 contains a conserved EKLF-binding CACC site within an intron that is closely associated with two conserved GATA1 binding sites. We show by a chromatin immunoprecipitation (ChIP) assays that the E2F4 intron and p18 promoter are occupied by EKLF in vivo. Together, these results suggest that EKLF is likely to directly regulate expression of key cell cycle genes in vivo to drive the switch from proliferation to differentiation of erythrocytes. The loss of EKLF is likely to result in aberrant proliferation and predisposition to leukemia

New integrated care models in England associated with small reduction in hospital admissions in longer-term: A difference-in-differences analysis

Closer integration of health and social care services has become a cornerstone policy in many developed countries, but there is still debate over what population and service level is best to target. In England, the 2019 Long Term Plan for the National Health Service included a commitment to spread the integration prototypes piloted under the Vanguard `New Care Models’ programme. The programme, running from 2015 to 2018, was one of the largest pilots in English history, covering around 9 % of the population. It was largely intended to design prototypes aimed at reducing hospital utilisation by moving specialist care out of hospital into the community and by fostering coordination of health, care and rehabilitation services for (i) the whole population (‘population-based sites’), or (ii) care home residents (‘care home sites’). We evaluate and compare the efficacy of the population-based and care home site integrated care models in reducing hospital utilisation. We use area-level monthly counts of emergency admissions and bed-days obtained from administrative data using a quasi-experimental difference-in-differences design. We found that Vanguard sites had higher hospital utilisation than non-participants in the pre-intervention period. In the post-intervention period, there is clear evidence of a substantial increase in emergency admissions among non-Vanguard sites. The Vanguard integrated care programme slowed the rise in emergency admissions, especially in care home sites and in the third and final year. There was no significant reduction in bed-days. In conclusion, integrated care policies should not be relied upon to make large reductions in hospital activity in the short-run, especially for population-based models