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This study identified the LARP6 La Module from Tetrabaena socialis (T. socialis), a four-celled green algae, in an effort to better understand the evolution of LARP6 structure and RNA-binding activity in multicellular eukaryotes. Using a combination of sequence alignments, domain boundary screens, and structural modelling, we recombinantly expressed and isolated the TsLARP6 La Module to > 98% purity for in vitro biochemical characterization. The La Module is stably folded and exerts minimal RNA binding activity against single-stranded homopolymeric RNAs. Surprisingly, it exhibits low micromolar binding affinity for the vertebrate LARP6 cognate ligand, a bulged-stem loop found in the 5'UTR of collagen type I mRNA, but does not bind double-stranded RNAs of similar size. These result suggests that the TsLARP6 La Module may prefer structured RNA ligands. In contrast, however, the TsLARP6 La Module does not exhibit the RNA chaperone activity that is observed in vertebrate homologs. Therefore, we conclude that protist LARP6 may have both distinct RNA ligands and binding mechanisms from the previously characterized LARP6 proteins of animals and vascular plants, thus establishing a distinct third class of the LARP6 protein family. 

Synopsis Wildlife health comparisons within and across populations and species are essential for population assessment and surveillance of emerging infectious diseases. Due to low costs and high informational yield, hematology is commonly used in the fields of ecoimmunology and disease ecology, yet consistency and proper reporting of methods within these fields are lacking. Previous investigations on various wildlife taxa have revealed noteworthy impacts of the vein used for blood collection on hematology measures. However, the impacts of venipuncture site on bats, a taxon of increasing interest in ecoimmunology and disease ecology, have not yet been tested. Here, we use a long-term study system in western Oklahoma to test the effect of venipuncture site on hematology parameters of the Mexican free-tailed bat (Tadarida brasiliensis) and cave myotis (Myotis velifer), two abundant and representative bat species from the families Molossidae and Vespertilionidae. Between September 2023 and October 2024, we collected paired peripheral blood from both the propatagial and intrafemoral veins in 25 individuals per species. We then quantified total red and white blood cells, reticulocyte counts, and leukocyte differentials and used generalized linear mixed models to compare parameters among venipuncture sites within and between bat species. Overall, venipuncture site had no effect on any hematology parameters; however, we revealed small differences in neutrophil and lymphocyte proportions between veins among the species. By contrast, we detected significant species-level differences in most cell measurements, which we propose could be explained by life-history strategy and phylogenetic differences. We encourage continued testing of additional venipuncture sites, and of the same venipuncture sites on different species, on hematology and other health metrics used in ecoimmunology and disease ecology. Lastly, we emphasize the importance of thorough method reporting in publications to enable transparent comparisons and accounting for even small sampling-based artifacts. All future efforts are especially important for bats to improve conservation monitoring, ecosystem services estimations, and their association with emerging infectious diseases. 

Climate change accelerates coral reef decline and jeopardizes recruitment essential for ecosystem recovery. Adult corals rely on a vital nutritional exchange with their symbiotic algae (Symbiodiniaceae), but the dynamics of reliance from fertilization to recruitment are understudied. We investigated the physiological, metabolomic, and transcriptomic changes across 13 developmental stages of Montipora capitata, a coral in Hawaiʻi that inherits symbionts from parent to egg. We found that embryonic development depends on maternally provisioned mRNAs and lipids, with a rapid shift to symbiont-derived nutrition in late developmental stages. Symbiont density and photosynthesis peak in swimming larvae to fuel pelagic dispersal. By contrast, respiratory demand increases significantly during metamorphosis and settlement, reflecting this energy-intensive morphological reorganization. Symbiont proliferation is driven by symbiont ammonium assimilation in larval stages with little evidence of nitrogen metabolism in the coral host. As development progresses, the host enhances nitrogen sequestration, regulating symbiont populations, and ensuring the transfer of fixed carbon to support metamorphosis, with both metabolomic and transcriptomic indicators of increased carbohydrate availability. Although algal symbiont community composition remained stable, bacterial communities shifted with ontogeny, associated with holobiont metabolic reorganization. Our study reveals extensive metabolic changes during development with increasing reliance on symbiont nutrition. Metamorphosis and settlement emerge as critical periods of energetic vulnerability to projected climate scenarios that destabilize symbiosis. This highly detailed characterization of symbiotic nutritional exchange during sensitive early life stages provides essential knowledge for understanding and forecasting the function of nutritional symbioses and, specifically, coral survival and recruitment in a future of climate change. 

We examine the arsenic distribution and its influence on dopant activation in poly-crystalline CdTe1−xSex solar cell absorbers prepared by vapor transport deposition followed by CdCl2 annealing. For as-deposited CdTe:As, local-electrode atom probe (LEAP) tomography reveals non-uniform distributions of arsenic clusters in the top “doped” layers. Following CdCl2 annealing, secondary ion mass spectrometry suggests that arsenic has diffused into the entire CdTe layer, while LEAP tomography reveals dissolution of the clusters, with nearly uniform distribution of arsenic atoms in CdTe. Since the arsenic fraction (fAs) is 1 × 1018 cm−3, but the hole density ranges from 7.5 to 9.5 × 1015 cm−3, we hypothesize that a large fraction of the arsenic has been incorporated into interstitial sites or cadmium substitutional sites, resulting in limited dopant activation. 

Restoration outcomes are notoriously difficult to predict and often fall short of restoration goals. Post‐restoration management actions may help overcome barriers to successful establishment, such as dispersal limitations and competition. Layering these management actions to increase the intensity of disturbances may improve restoration outcomes, but they also can be expensive and laborious, depending on the intensity or number of actions implemented. We investigated a series of disturbance intensities on previously restored tallgrass prairies using a randomized block design. Combinations of seeding, harrowing (low intensity disturbance), disking (high intensity disturbance), and herbicide were implemented after a prescribed burn. After 11–14 years, we measured percent cover of all species present to determine long‐term effectiveness. We found that the high intensity disturbance treatment increased native species richness by over 40% and native species Shannon diversity by 15% when compared to control plots. Overall diversity and composition of the plots varied among sites that were treated in different years, indicating that seed mix composition and site conditions were still likely important determinants of community outcomes. Regardless, the consistency of the high intensity management actions to increase site richness and diversity after more than a decade may allow managers to achieve restoration goals, even if later management is limited, justifying the time and resources to enhance existing restorations.