Building connectivity at the research-policy interface in Aotearoa through a public sector postdoctoral fellowship scheme

Improving connectivity at the research-policy interface and supporting career development for early career researchers are twin goals of government-funded research systems in Aotearoa New Zealand and globally. The Aotearoa Ministry for Business, Innovation, and Employment (MBIE) began the process of overhauling the research system to achieve these, and other, goals through Te Ara Paerangi Future Pathways programme in 2021. Here, I propose a public sector postdoctoral fellowship scheme to place PhD graduates into roles within central government agencies, which MBIE could implement during the first phase of Te Ara Paerangi Future Pathways reforms. The Fellowship would strengthen collaboration at the research-policy interface and provide a low investment, high impact, opportunity to retain talent in Aotearoa by developing flexible career pathways for PhD graduates. &nbsp

Roles for common MLL/COMPASS subunits and the 19S proteasome in regulating CIITA pIV and MHC class II gene expression and promoter methylation

<p>Abstract</p> <p>Background</p> <p>Studies indicate that the 19S proteasome contributes to chromatin reorganization, independent of the role the proteasome plays in protein degradation. We have previously shown that components of the 19S proteasome are crucial for regulating inducible histone activation events in mammalian cells. The 19S ATPase Sug1 binds to histone-remodeling enzymes, and in the absence of Sug1, a subset of activating epigenetic modifications including histone H3 acetylation, H3 lysine 4 trimethylation and H3 arginine 17 dimethylation are inhibited at cytokine-inducible major histocompatibilty complex (MHC)-II and class II transactivator (CIITA) promoters, implicating Sug1 in events required to initiate mammalian transcription.</p> <p>Results</p> <p>Our previous studies indicate that H3 lysine 4 trimethylation at cytokine-inducible MHC-II and CIITA promoters is dependent on proteolytic-independent functions of 19S ATPases. In this report, we show that multiple common subunits of the mixed lineage leukemia (MLL)/complex of proteins associated with Set I (COMPASS) complexes bind to the inducible MHC-II and CIITA promoters; that overexpressing a single common MLL/COMPASS subunit significantly enhances promoter activity and MHC-II <it>HLA-DRA </it>expression; and that these common subunits are important for H3 lysine 4 trimethylation at MHC-II and CIITA promoters. In addition, we show that H3 lysine 27 trimethylation, which is inversely correlated with H3 lysine 4 trimethylation, is significantly elevated in the presence of diminished 19S ATPase Sug1.</p> <p>Conclusion</p> <p>Taken together, these experiments suggest that the 19S proteasome plays a crucial role in the initial reorganization of events enabling the relaxation of the repressive chromatin structure surrounding inducible promoters.</p

Reconstruction of Antarctic accumulation from 1801-2000 CE

&lt;p&gt;An annually resolved reconstruction of gridded snow accumulation anomalies over Antarctica, from 1801-2000 CE.&nbsp;&lt;/p&gt;&lt;p&gt;Reconstructions are generated using the Last Millennium Reanalysis data assimilation framework (Hakim et al., 2016; Tardif et al., 2019), a comprehensive ice core proxy database, and a multi-model ensemble of climate simulations.&nbsp;&lt;/p&gt;&lt;p&gt;We incorporate a database of water isotope (Stenni et al., 2017) and accumulation (Thomas et al., 2017) ice core records from the Pages 2k consortium, in addition to individual records from the South Pole ice core (Kahle et al., 2021), Derwael Ice Rise (Philippe et al., 2016), and the PIG2010, DIV2010, and THW2010 sites (Criscitiello et al., 2013).&nbsp;&lt;/p&gt;&lt;p&gt;The multi-model ensemble is constructed using nine CMIP5 Last Millennium Simulations: CCSM4 (Gent et al., 2011), iCESM (Brady et al., 2019), BCC-CSM1.1 (Wu et al., 2014), CSIRO Mk3L (Phipps et al., 2012), FGOALS-s2 (Bao et al., 2013), GISS-E2-R (Schmidt et al., 2014), HadCM3 (Collins et al., 2001), IPSL-CM5A-LR (Dufresne et al., 2013), and MPI-ESM (Gutjahr et al., 2019).&nbsp;&lt;/p&gt

20th‐Century Antarctic Sea Level Mitigation Driven by Uncertain East Antarctic Accumulation History

Abstract Increasing snow accumulation over the Antarctic Ice Sheet may mitigate future sea level rise. However, current estimates of mitigation potential are poorly constrained due to limited records of past variability. We present an annually resolved reconstruction of Antarctic snow accumulation from 1801 to 2000 CE, employing a paleoclimate data assimilation methodology to integrate ice core records with a multi‐model ensemble of climate simulations. Our reconstruction correlates well with instrumental reanalysis, and we find that Antarctic accumulation rates increased over the 20th‐century, resulting in a modest amount (∼1 mm) of sea level mitigation. Mitigation is primarily driven by an accelerating trend since around 1970. Our results contrast with previous mitigation estimates of ∼10–12 mm; this discrepancy is due to poorly constrained baseline estimates of 19th‐century accumulation in East Antarctica. Our reconstruction suggests that the uncertainty of future sea level mitigation from increasing Antarctic accumulation has been underestimated

Drivers of Last Millennium Antarctic Climate Evolution in an Ensemble of Community Earth System Model Simulations

Improved understanding of the drivers of climate variability, particularly over the last millennium, and its influence on Antarctic ice melt have important implications for projecting ice sheet resilience in a changing climate. Here, we investigated the variability in Antarctic climate and sea ice extent during the last millennium (850&ndash;1850 CE) by comparing paleoenvironmental reconstructions with simulations from the Community Earth System Model Last Millennium Ensemble (CESM-LME). Atmospheric and oceanic response to external forcing in CESM-LME simulations typically take the form of an Antarctic dipole: cooling over most of Antarctica and warming east of the Antarctic Peninsula. This configuration is also observed in ice core records. Unforced variability and a dipole response to large volcanic eruptions contribute to weaker cooling in the Antarctic than the Arctic, consistent with the absence of a strong volcanic signal in Antarctic ice core records. The ensemble does not support a clear link between the dipole pattern and baseline shifts in the Southern Annular Mode and El Ni&ntilde;o-Southern Oscillation proposed by some paleoclimate reconstructions. Our analysis provides a point of comparison for paleoclimate reconstructions and highlights the role of internal climate variability in driving modeled last millennium climate evolution in the Antarctic

Drivers of Last Millennium Antarctic Climate Evolution in an Ensemble of Community Earth System Model Simulations

Improved understanding of the drivers of climate variability, particularly over the last millennium, and its influence on Antarctic ice melt have important implications for projecting ice sheet resilience in a changing climate. Here, we investigated the variability in Antarctic climate and sea ice extent during the last millennium (850–1850 CE) by comparing paleoenvironmental reconstructions with simulations from the Community Earth System Model Last Millennium Ensemble (CESM-LME). Atmospheric and oceanic response to external forcing in CESM-LME simulations typically take the form of an Antarctic dipole: cooling over most of Antarctica and warming east of the Antarctic Peninsula. This configuration is also observed in ice core records. Unforced variability and a dipole response to large volcanic eruptions contribute to weaker cooling in the Antarctic than the Arctic, consistent with the absence of a strong volcanic signal in Antarctic ice core records. The ensemble does not support a clear link between the dipole pattern and baseline shifts in the Southern Annular Mode and El Niño-Southern Oscillation proposed by some paleoclimate reconstructions. Our analysis provides a point of comparison for paleoclimate reconstructions and highlights the role of internal climate variability in driving modeled last millennium climate evolution in the Antarctic