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1. The long and short of the S ‐locus in Turnera (Passifloraceae)

   https://doi.org/10.1111/nph.15970  

   Shore, Joel S. ; Hamam, Hasan J. ; Chafe, Paul D. J. ; Labonne, Jonathan D. J. ; Henning, Paige M. ; McCubbin, Andrew G. ( July 2019 , New Phytologist)

   Distyly is an intriguing floral adaptation that increases pollen transfer precision and restricts inbreeding. It has been a model system in evolutionary biology since Darwin. Although theS‐locus determines the long‐ and short‐styled morphs, the genes were unknown inTurnera. We have now identified these genes.

   We used deletion mapping to identify, and then sequence,BACclones and genome scaffolds to constructS/shaplotypes. We investigated candidate gene expression, hemizygosity, and used mutants, to explore gene function.

   Thes‐haplotype possessed 21 genes collinear with a region of chromosome 7 of grape. TheS‐haplotype possessed three additional genes and two inversions.TsSPH1was expressed in filaments and anthers,TsYUC6in anthers andTsBAHDin pistils. Long‐homostyle mutants did not possessTsBAHDand a short‐homostyle mutant did not expressTsSPH1.

   Three hemizygous genes appear to determine S‐morph characteristics inT. subulata. Hemizygosity is common to all distylous species investigated, yet the genes differ. The pistil candidate gene,TsBAHD, differs from that ofPrimula, but both may inactivate brassinosteroids causing short styles.TsYUC6is involved in auxin synthesis and likely determines pollen characteristics.TsSPH1is likely involved in filament elongation. We propose an incompatibility mechanism involvingTsYUC6andTsBAHD.

    

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2. Evolution and future of urban ecological science: ecology in , of , and for the city

   https://doi.org/10.1002/ehs2.1229  

   Pickett, Steward T. ; Cadenasso, Mary L. ; Childers, Daniel L. ; McDonnell, Mark J. ; Zhou, Weiqi ( July 2016 , Ecosystem Health and Sustainability)
3. In Vitro and in Vivo Analyses of the Effects of Source, Length, and Charge on the Cytotoxicity and Immunocompatibility of Cellulose Nanocrystals

   https://doi.org/10.1021/acsbiomaterials.0c01618  

   Weiss, Adam M. ; Macke, Nicholas ; Zhang, Yefei ; Calvino, Céline ; Esser-Kahn, Aaron P. ; Rowan, Stuart J. ( April 2021 , ACS Biomaterials Science & Engineering)

   null (Ed.)
4. Expression and regulation of the mer operon in Thermus thermophilus

   https://doi.org/10.1111/1462-2920.14953  

   Norambuena, Javiera ; Miller, Maximilian ; Boyd, Jeffrey M. ; Barkay, Tamar ( March 2020 , Environmental Microbiology)

   Mercury (Hg) is a highly toxic and widely distributed heavy metal, which some Bacteria and Archaea detoxify by the reduction of ionic Hg (Hg[II]) to the elemental volatile form, Hg(0). This activity is specified by themeroperon. Themeroperon of the deeply branching thermophileThermus thermophilusHB27 encodes for, anO‐acetyl‐l‐homoacetylserine sulfhydrylase (Oah2), a transcriptional regulator (MerR), a hypothetical protein (hp) and a mercuric reductase (MerA). Here, we show that this operon has two convergently expressed and differentially regulated promoters. An upstream promoter, P_oah, controls the constitutive transcription of the entire operon and a second promoter (P_mer), located withinmerR, is responsive to Hg(II). In the absence of Hg(II), the transcription ofmerAis basal and when Hg(II) is present,merAtranscription is induced. This response to Hg(II) is controlled by MerR and genetic evidence suggests that MerR acts as a repressor and activator of P_mer. When the wholemerR, including P_mer, is removed,merAis transcribed from P_oahindependently of Hg(II). These results suggest that the transcriptional regulation ofmerinT.thermophilusis both similar to, and different from, the well‐documented regulation of proteobacterialmersystems, possibly representing an early step in the evolution ofmer‐operon regulation.

    

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5. The XXL Survey. XLII. The LX − σ v relation of galaxy groups and clusters detected in the XXL and GAMA surveys

   https://doi.org/10.1093/mnras/stab3626  

   Giles, P. A. ; Robotham, A. ; Ramos-Ceja, M. E. ; Maughan, B. J. ; Sereno, M. ; McGee, S. ; Phillipps, S. ; Iovino, A. ; Turner, D. J. ; Adami, C. ; et al ( February 2022 , Monthly Notices of the Royal Astronomical Society)

   The XXL Survey is the largest homogeneous survey carried out with XMM-Newton. Covering an area of 50 deg2, the survey contains several hundred galaxy clusters out to a redshift of ≈2, above an X-ray flux limit of ∼6 × 10−15 er g cm−2 s−1. The GAMA spectroscopic survey of ∼300 000 galaxies covers ≈286 deg2, down to an r-band magnitude of r < 19.8 mag. The region of overlap of these two surveys (covering 14.6 deg2) represents an ideal opportunity to study clusters selected via two independent selection criteria. Generating two independently selected samples of clusters, one drawn from XXL (spanning a redshift range 0.05 ≤ z ≤ 0.3) and another from GAMA (0.05 ≤ z ≤ 0.2), both spanning 0.2 ≲ M500 ≲ 5 × 1014 M⊙, we investigate the relationship between X-ray luminosity and velocity dispersion (LX − σv relation). Comparing the LX − σv relation between the X-ray selected and optically selected samples, when not accounting for the X-ray selection, we find that the scatter of the X-ray selected sample is 2.7 times higher than the optically selected sample (at the 3.7σ level). Accounting for the X-ray selection to model the LX − σv relation, we find that the difference in the scatter increases (with the X-ray selected sample having a scatter 3.4 times larger than the optically selected sample). Although the scatter of the optically selected sample is lower, we find 13 optically selected GAMA groups undetected in X-rays. Inspection of the difference in magnitude between the first and second brightest galaxies in the cluster, and a stacked X-ray image of these 13 groups, suggests that these are young systems still in the process of forming.

    

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