Geographic range extension of Speke's Hinge-back Tortoise Kinixys spekii Gray, 1863

Kinixys spekii has a wide distribution range across sub-Saharan Africa, having been reported from Angola, Botswana, Burundi, the Democratic Republic of the Congo, eSwatini, Kenya, Malawi, Mozambique, Namibia, South Africa, Tanzania, Zambia, and Zimbabwe. Kinixys spekii inhabits savannah and dry bushveld habitats and was previously considered an inland species. However, recent records suggest a more extensive geographical distribution. Here, we provide genetically verifed records for Angola, South Africa, and Mozambique, and discuss reliable sightings for Rwanda. These new records extend the range signifcantly to the east and west, and provide evidence for the occurrence of this species along the coast of the Indian Ocean in South Africa and Mozambique.© 2019 Ihlow et al. This is an open access article distributed under the terms of the Creative Commons Attribution License [Attribution 4.0 International (CC BY 4.0): https://creativecommons.org/licenses/by/4.0/], which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. The official and authorized publication credit sources, which will be duly enforced, are as follows: offcial journal title Amphibian & Reptile Conservation; official journal website: amphibian-reptile-conservation.org

Contributions to the herpetofauna of the Angolan Okavango-Cuando-Zambezi river drainages. Part 3 : Amphibians

This article is the third and final installment of the herpetofaunal results obtained from a series of rapid biodiversity surveys of the upper Cuito, Cubango, Cuando, Zambezi, and Kwanza River basins in Angola. The amphibian survey results are presented along with an updated checklist of the historical and current records of amphibians from the southeastern region of Angola. A total of 1,114 new amphibian records were documented, comprising 37 species, bringing the total number of recognized amphibian species in this region to 49. These surveys documented two new country records (Hyperolius cf. inyangae and Kassinula wittei) and at least two candidate new species, and elevated Amnirana adiscifera stat. nov. (which now encompasses the western green form formerly regarded as A. darlingi). Finally, updated distribution maps for all of Angola are provided for all the species encountered within the study region.The NRF-SAIAB Institutional Support System.http://amphibian-reptile-conservation.orgZoology and Entomolog

Contributions to the herpetofauna of the Angolan Okavango- Cuando-Zambezi river drainages. Part 2 : Lizards (Sauria), chelonians, and crocodiles

This work is the second report of the results obtained from a series of rapid biodiversity surveys of the upper Cuito, Cubango, Cuando, Zambezi, and Kwanza River basins in Angola, which were conducted between 2015 and 2019 in conjunction with the National Geographic Okavango Wilderness Project. The herpetofauna of this region are poorly documented and the results of these surveys help to address the knowledge gap regarding the conservation importance of this region. Here, an updated checklist is provided for the current and historical records of lizards, chelonians, and crocodiles from the southeastern region of Angola. A total of 369 new records were documented comprising 40 species, bringing the total number of recognized lizard, chelonian, and crocodile species in this region to 58. These surveys documented four new country records (i.e., Lygodactylus chobiensis, Agama armata, Pachydactylus wahlbergii, and Ichnotropis cf. grandiceps) and increased the total number of reptile species known to occur in Angola (excluding snakes) from approximately 157 to 161. Finally, updated distribution maps for the whole country are provided for all of the species encountered in this study.Este trabalho é a segunda parte dos resultados de uma série de levantamentos rápidos de biodiversidade realizados nas bacias dos rios Cuito, Cubango, Cuando, Zambeze e Kwanza em Angola, entre 2015 e 2019, em conjunto com o National Geographic Okavango Wilderness Project. A herpetofauna desta região está pouco documentada, e os resultados destes levantamentos ajudarão a colmatar a lacuna de conhecimento sobre a importância da sua conservação. Aqui apresentamos uma lista atualizada de registos históricos e recentes dos lagartos, quelónios e crocodilos do sudeste de Angola. Ao todo, foram documentado 369 novos registros, relativos a 40 espécies, elevando o número total de espécies desses três grupos na região para 58. Nestes levantamentos foram registadas em Angola pela primeira vez quatro as espécies de lagartos (Lygodactylus chobiensis, Agama armata, Pachydactylus wahlbergii, Ichnotropis cf. grandiceps), aumentando o número total de espécies conhecidas de répteis (excluindo cobras) de Angola de 157 para 161. Por fim, apresentamos mapas de ocorrência/distribuição atualizados das espécies encontradas neste estudo para todo o país.The Wild Bird Trust, which administers the National Geographic Okavango Wilderness Project.amphibian-reptile-conservation.orgam2023Zoology and Entomolog

Impedance-based phenotypic readout of transporter function: a case for glutamate transporters

Excitatory amino acid transporters (EAAT/SLC1) mediate Na+-dependent uptake of extracellular glutamate and are potential drug targets for neurological disorders. Conventional methods to assess glutamate transport in vitro are based on radiolabels, fluorescent dyes or electrophysiology, which potentially compromise the cell's physiology and are generally less suited for primary drug screens. Here, we describe a novel label-free method to assess human EAAT function in living cells, i.e., without the use of chemical modifications to the substrate or cellular environment. In adherent HEK293 cells overexpressing EAAT1, stimulation with glutamate or aspartate induced cell spreading, which was detected in real-time using an impedance-based biosensor. This change in cell morphology was prevented in the presence of the Na+/K+-ATPase inhibitor ouabain and EAAT inhibitors, which suggests the substrate-induced response was ion-dependent and transporter-specific. A mechanistic explanation for the phenotypic response was substantiated by actin cytoskeleton remodeling and changes in the intracellular levels of the osmolyte taurine, which suggests that the response involves cell swelling. In addition, substrate-induced cellular responses were observed for cells expressing other EAAT subtypes, as well as in a breast cancer cell line (MDA-MB-468) with endogenous EAAT1 expression. These findings allowed the development of a label-free high-throughput screening assay, which could be beneficial in early drug discovery for EAATs and holds potential for the study of other transport proteins that modulate cell shape.Medicinal Chemistr

Phonotactic response of female crickets on the Kramer treadmill: methodology, sensory and behavioural implications

Since population-level variation in female mating preferences can shape intraspecific communication systems within the context of sexual selection it is essential to quantify these preferences and their sources of variation. We calculated individual female response functions for four male calling song traits in the field cricket Gryllus bimaculatus, by performing untethered phonotaxis measurements on a spherical locomotor compensator (Kramer treadmill). Firstly, we quantify the population-level sources of phonotactic variation and correct for factors that adversely affect this measurement. Secondly, we develop methodology for the characterisation of individual female phonotactic response functions suitable for population-level analyses and demonstrate the applicability of our method with respect to recent literature on Orthopteran acoustic communication. Phonotaxis towards a preferred stimulus on different occasions is highly repeatable, with lower repeatabilities away from the most preferred signal traits. For certain male signal traits, female preference and selectivity are highly repeatable. Although phonotactic response magnitude deteriorated with age, preference functions of females remained the same during their lifetimes. Finally, the limitations of measuring phonotaxis using a spherical locomotor compensator are described and discussed with respect to the estimation of the selectivity of female response

Matched Filters, Mate Choice and the Evolution of Sexually Selected Traits

Background Fundamental for understanding the evolution of communication systems is both the variation in a signal and how this affects the behavior of receivers, as well as variation in preference functions of receivers, and how this affects the variability of the signal. However, individual differences in female preference functions and their proximate causation have rarely been studied. Methodology/Principal Findings Calling songs of male field crickets represent secondary sexual characters and are subject to sexual selection by female choice. Following predictions from the “matched filter hypothesis” we studied the tuning of an identified interneuron in a field cricket, known for its function in phonotaxis, and correlated this with the preference of the same females in two-choice trials. Females vary in their neuronal frequency tuning, which strongly predicts the preference in a choice situation between two songs differing in carrier frequency. A second “matched filter” exists in directional hearing, where reliable cues for sound localization occur only in a narrow frequency range. There is a strong correlation between the directional tuning and the behavioural preference in no-choice tests. This second “matched filter” also varies widely in females, and surprisingly, differs on average by 400 Hz from the neuronal frequency tuning. Conclusions/Significance Our findings on the mismatch of the two “matched filters” would suggest that the difference in these two filters appears to be caused by their evolutionary history, and the different trade-offs which exist between sound emission, transmission and detection, as well as directional hearing under specific ecological settings. The mismatched filter situation may ultimately explain the maintenance of considerable variation in the carrier frequency of the male signal despite stabilizing selection

Discriminating physiological from non-physiological interfaces in structures of protein complexes: A community-wide study

Reliably scoring and ranking candidate models of protein complexes and assigning their oligomeric state from the structure of the crystal lattice represent outstanding challenges. A community-wide effort was launched to tackle these challenges. The latest resources on protein complexes and interfaces were exploited to derive a benchmark dataset consisting of 1677 homodimer protein crystal structures, including a balanced mix of physiological and non-physiological complexes. The non-physiological complexes in the benchmark were selected to bury a similar or larger interface area than their physiological counterparts, making it more difficult for scoring functions to differentiate between them. Next, 252 functions for scoring protein-protein interfaces previously developed by 13 groups were collected and evaluated for their ability to discriminate between physiological and non-physiological complexes. A simple consensus score generated using the best performing score of each of the 13 groups, and a cross-validated Random Forest (RF) classifier were created. Both approaches showed excellent performance, with an area under the Receiver Operating Characteristic (ROC) curve of 0.93 and 0.94, respectively, outperforming individual scores developed by different groups. Additionally, AlphaFold2 engines recalled the physiological dimers with significantly higher accuracy than the non-physiological set, lending support to the reliability of our benchmark dataset annotations. Optimizing the combined power of interface scoring functions and evaluating it on challenging benchmark datasets appears to be a promising strategy

Enzyme intermediates captured on the fly by mix-and-inject serial crystallography

Background Ever since the first atomic structure of an enzyme was solved, the discovery of the mechanism and dynamics of reactions catalyzed by biomolecules has been the key goal for the understanding of the molecular processes that drive life on earth. Despite a large number of successful methods for trapping reaction intermediates, the direct observation of an ongoing reaction has been possible only in rare and exceptional cases. Results Here, we demonstrate a general method for capturing enzyme catalysis in action by mix-and-inject serial crystallography (MISC). Specifically, we follow the catalytic reaction of the Mycobacterium tuberculosis β-lactamase with the third-generation antibiotic ceftriaxone by time-resolved serial femtosecond crystallography. The results reveal, in near atomic detail, antibiotic cleavage and inactivation from 30 ms to 2s. Conclusions MISC is a versatile and generally applicable method to investigate reactions of biological macromolecules, some of which are of immense biological significance and might be, in addition, important targets for structure-based drug design. With megahertz X-ray pulse rates expected at the Linac Coherent Light Source II and the European X-ray free-electron laser, multiple, finely spaced time delays can be collected rapidly, allowing a comprehensive description of biomolecular reactions in terms of structure and kinetics from the same set of X-ray data.This work was supported by the National Science Foundation (NSF)-Science and Technology Center (STC) BioXFEL through award STC-1231306, and in part by the US Department of Energy, Office of Science, Basic Energy Sciences under contract DE-SC0002164 (to A.O., algorithm design and development) and by the NSF under contract number 1551489 (to A.O., underlying analytical models). Portions of this research were performed at the Linac Coherent Light Source (LCLS). Use of the LCLS, SLAC National Accelerator Laboratory, is supported by the US Department of Energy, Office of Science, Basic Energy Sciences under contract DE-AC02-76SF00515. This material is based upon work supported by the NSF Graduate Research Fellowship Program to J.L.O. under grant no. 1450681. The work was also supported by funds from the National Institutes of Health grants R01 GM117342-01 and R01 GM095583, by funds from the Biodesign Center for Applied Structural Discovery at Arizona State University, and the US Department of Energy through Lawrence Livermore National Laboratory under contract DE-AC52-07NA27344. Part of this work was also supported by program-oriented funds of the Helmholtz Association

The bii4africa dataset of faunal and floral population intactness estimates across Africa's major land uses

This is the final version. Available on open access from Nature Research via the DOI in this recordCode availability: R code for calculating aggregated intactness scores for a focal region (e.g., ecoregion or country) and/or taxonomic group can be downloaded with the bii4africa dataset on Figshare; see Data Records section.Sub-Saharan Africa is under-represented in global biodiversity datasets, particularly regarding the impact of land use on species' population abundances. Drawing on recent advances in expert elicitation to ensure data consistency, 200 experts were convened using a modified-Delphi process to estimate 'intactness scores': the remaining proportion of an 'intact' reference population of a species group in a particular land use, on a scale from 0 (no remaining individuals) to 1 (same abundance as the reference) and, in rare cases, to 2 (populations that thrive in human-modified landscapes). The resulting bii4africa dataset contains intactness scores representing terrestrial vertebrates (tetrapods: ±5,400 amphibians, reptiles, birds, mammals) and vascular plants (±45,000 forbs, graminoids, trees, shrubs) in sub-Saharan Africa across the region's major land uses (urban, cropland, rangeland, plantation, protected, etc.) and intensities (e.g., large-scale vs smallholder cropland). This dataset was co-produced as part of the Biodiversity Intactness Index for Africa Project. Additional uses include assessing ecosystem condition; rectifying geographic/taxonomic biases in global biodiversity indicators and maps; and informing the Red List of Ecosystems.Jennifer Ward Oppenheimer Research Gran