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1. The R -Process Alliance: Analysis of limited- r stars

   https://doi.org/10.1051/0004-6361/202449376  

   Xylakis-Dornbusch, T; Hansen, T T; Beers, T C; Christlieb, N; Ezzeddine, R; Frebel, A; Holmbeck, E; Placco, V M; Roederer, I U; Sakari, C M; et al (August 2024, Astronomy & Astrophysics)

   Context.In recent years, theR-Process Alliance (RPA) has conducted a successful search for stars that are enhanced in elements produced by the rapid neutron-capture (r-)process. In particular, the RPA has uncovered a number of stars that are strongly enriched in lightr-process elements, such as Sr, Y, and Zr. These so-called limited-rstars were investigated to explore the astrophysical production site(s) of these elements. Aims.We investigate the possible formation sites for light neutron-capture elements by deriving detailed abundances for neutron-capture elements from high-resolution spectra with a high signal-to-noise ratio of three limited-rstars. Methods.We conducted a kinematic analysis and a 1D local thermodynamic equilibrium spectroscopic abundance analysis of three stars. Furthermore, we calculated the lanthanide mass fraction (X_La) of our stars and of limited-rstars from the literature. Results.We found that the abundance pattern of neutron-capture elements of limited-rstars behaves differently depending on their [Ba/Eu] ratios, and we suggest that this should be taken into account in future investigations of their abundances. Furthermore, we found that theX_Laof limited-rstars is lower than that of the kilonova AT2017gfo. The latter seems to be in the transition zone between limited-rX_Laand that ofr-I andr-II stars. Finally, we found that unliker-I andr-II stars, the current sample of limited-rstars is largely born in the Galaxy and is not accreted. 

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2. In silico screening of P , N -ligands facilitates optimization of Au( iii )-mediated S -arylation

   https://doi.org/10.1039/D4SC05920D  

   Treacy, Joseph W; Tilden, James_A R; Chao, Elaine Y; Fu, Zihuan; Spokoyny, Alexander M; Houk, K N; Maynard, Heather D (February 2025, Chemical Science)

   In silicoexamination of 13P,N-ligated Au(iii) OACs determined the key mechanistic factors governing Au(iii)-mediatedS-arylation. Three complexes were synthesized which exhibited bimolecular coordination rate constants as high as 20 200 M⁻¹s⁻¹. 

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3. Identification and expression analysis of Phosphate Transporter 1 ( PHT1 ) genes in the highly phosphorus‐use‐efficient Hakea prostrata (Proteaceae)

   https://doi.org/10.1111/pce.15088  

   Nestor, Benjamin J; Bird, Toby; Severn‐Ellis, Anita A; Bayer, Philipp E; Ranathunge, Kosala; Prodhan, M Asaduzzaman; Dassanayake, Maheshi; Batley, Jacqueline; Edwards, David; Lambers, Hans; et al (December 2024, Plant, Cell & Environment)

   Abstract Heavy and costly use of phosphorus (P) fertiliser is often needed to achieve high crop yields, but only a small amount of applied P fertiliser is available to most crop plants.Hakea prostrata(Proteaceae) is endemic to the P‐impoverished landscape of southwest Australia and has several P‐saving traits. We identified 16 members of thePhosphate Transporter 1(PHT1) gene family (HpPHT1;1‐HpPHT1;12d) in a long‐read genome assembly ofH. prostrata. Based on phylogenetics, sequence structure and expression patterns, we classifiedHpPHT1;1as potentially involved in Pi uptake from soil andHpPHT1;8andHpPHT1;9as potentially involved in Pi uptake and root‐to‐shoot translocation. Three genes,HpPHT1;4, HpPHT1;6 andHpPHT1;8, lacked regulatoryPHR1‐binding sites (P1BS) in the promoter regions. Available expression data forHpPHT1;6andHpPHT1;8indicated they are not responsive to changes in P supply, potentially contributing to the high P sensitivity ofH. prostrata. We also discovered a Proteaceae‐specific clade of closely‐spacedPHT1genes that lacked conserved genetic architecture among genera, indicating an evolutionary hot spot within the genome. Overall, the genome assembly ofH. prostrataprovides a much‐needed foundation for understanding the genetic mechanisms of novel adaptations to low P soils in southwest Australian plants. 

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4. The period gene alters daily and seasonal timing in Ostrinia nubilalis

   https://doi.org/10.1101/2024.11.02.621642  

   Dayton, Jacob N; Dopman, Erik B (November 2024, bioRxiv)

   Summary The timing of insects’ daily (feeding, movement) and seasonal (diapause, migration) rhythms affects their population dynamics and distribution. Yet, despite their implications for insect conservation and pest management, the genetic mechanisms underlying variation in timing are poorly understood. Prior research in the European corn borer moth (Ostrinia nubilalis) associated ecotype differences in seasonal diapause and daily activity with genetic variation at the circadian clock geneperiod(per). Here, we demonstrate that populations with divergent allele frequencies atperexhibit differences in daily behavior, seasonal development, and the expression of circadian clock genes. Specifically, later daily activity and shortened diapause were associated with a reduction and delay in the abundance of cyclingpermRNA. CRISPR/Cas9-mediated mutagenesis revealed thatperand/or an intact circadian clock network were essential for the appropriate timing of daily behavior and seasonal responsiveness. Furthermore, a reduction ofpergene dosage inperheterozygous mutants (per^-/+) pleiotropically decreased the diapause incidence, shortened post-diapause development, and delayed the timing of daily behavior, in a manner phenotypically reminiscent of wild-type individuals. Altogether, this combination of observational and experimental research strongly suggests thatperis a master regulator of biological rhythms and may contribute to the observed life cycle differences between bivoltine (two generation) and univoltine (one generation)O. nubilalis. HighlightsNatural ecotypes with divergentperiod(per) genotypes differ in their daily and seasonal responses to photoperiodLater daily activity, reduced diapause incidence, and shorter post-diapause development is associated with reducedpermRNA abundanceperis essential for short-day recognition and daily timingReducedpergene dosage shortened post-diapause development and delayed locomotor activity 

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5. Humanization of the rpb9 locus in fission yeast reveals conserved and divergent roles of rpb9 and human POLR2I

   https://doi.org/10.64898/2026.04.02.716003  

   Finkel, Jared M; Williams, Micah G; Nirmal, Mamta B; Pandey, Samakshi; Howe, Erik D; Liu, Cameron T; Lohman, Jeremy R; Sharma, Nimisha; Vo, Tommy V (April 2026, bioRxiv)

   Abstract Background/ObjectivesRNA polymerase II is a multifunctional complex that is critical for gene regulation and environmental responses. Its POLR2I subunit in human is associated with various pathologies, including cancer chemoresistance. However, much of our understanding of how POLR2I could function indirectly derives from studies of its homologs in yeasts called Rpb9. Here, we endogenously humanized therpb9gene of the fission yeastSchizosaccharomyces pombeto examine the functional capabilities of POLR2I. MethodsWe edited the genomicrpb9locus inS. pombeso that it encodes the human POLR2I protein, and investigated functional and structural conservation. ResultsWith our humanized yeast system, we find widespread functional complementation by humanPOLR2IofS. pombe rpb9roles in yeast growth, chronological aging, and stress responses. We also find thatPOLR2Icomplements novel roles for yeastrpb9in facultative heterochromatin assembly, resistance against the chemotherapy 5-fluorouracil, and resistance against the fungicide thiabendazole. In contrast, we find thatPOLR2Icannot complement the role ofrpb9in resistance against the transcription elongation inhibitor 6-azauracil (6-AU) in our system. Interestingly,POLR2Icould complement 6-AU resistance if ectopically expressed. Lastly, we observe extensive structural homology between Rpb9 and POLR2I proteins. ConclusionsOur study establishes an endogenous cross-species gene complementation strategy that uncovers both conserved and rewired functions of fission yeastrpb9and its human homolog,POLR2I. In addition to validating conserved roles, we also identified conservation of previously unrecognized roles ofrpb9in heterochromatin formation and chemoresistance. 

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