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Biology subjects

Beatty, C.

Publications and source records attributed to Beatty, C..

3 recordsLinked to original sources

Sex in the City: Reproductive Behaviors of Dragonflies across an Urban Landscape

Anthropogenic cityscapes provide complex habitats that influence animal communication and movement patterns, which are generally understudied in aquatic and semi-aquatic organisms. Community science, referring to public participation in scientific research, is an important tool for recording occurrence records and behavioral observations of understudied urban species. Boise, Idaho (USA), one of the fastest-growing cities in North America, has a long-established community science program for documenting occurrences of the semi-aquatic insect order Odonata (dragonflies and damselflies), making the city an ideal study system for comparing behavioral observations from community science with observations recorded using AI driven iNaturalist. In this study, we test the accuracy of iNaturalist observations and volunteer surveys to characterize dragonfly reproductive behaviors (tandem flight and tandem perching, oviposition, and mating) in the city, and use these observations to determine which dragonflies are using the urban landscape as reproductive habitat. The total numbers of species observations by volunteers and on iNaturalist in Boise were strongly correlated, while reproductive observations showed a strong observational threshold, as reproductive behaviors were rarely identified in less-observed species. iNaturalist tended to underrepresent total occurrences of ''flyer'' species, which rarely perch, while volunteer surveys underrepresented occurrences and reproductive behaviors of a more cyclical species that did not appear to be abundant in the field season in which this study was conducted. Our findings suggest that Boise provides suitable breeding habitat for both migratory and resident dragonflies. Species distribution models of three migratory and three putatively migratory species further demonstrate that these species would be expected in southwestern Idaho regardless of the presence of a city, and have persisted through urban development. This research demonstrates the value of community science in conducting basic research on understudied urban-dwelling species, although findings must be considered alongside potential biases.

ecology↗

Nef dimerization defect abrogates HIV viremia and associated immune dysregulation in the Bone Marrow-Liver-Thymus-Spleen (BLTS) humanized mouse model

Loss of function mutations in the human immunodeficiency virus (HIV) negative factor (Nef) gene are associated with reduced viremia, robust T cell immune responses, and delayed acquired immunodeficiency syndrome (AIDS) progression in humans. In vitro studies have shown that mutations in the Nef dimerization interface significantly attenuate viral replication and impair host defense. However, in vivo, mechanistic studies on the role of Nef dimerization in HIV infection are lacking. Humanized rodents with human immune cells are robust platforms for investigating the interactions between HIV and the human immune system. The bone marrow-liver-thymus-spleen (BLTS) humanized mouse model carries human immune cells and lymphoid tissues that facilitate anti-viral immune responses. Here, we employed the BLTS-humanized mouse model to demonstrate that preventing Nef dimerization abrogates HIV viremia and the associated immune dysregulation. This suggests that Nef dimerization may be a therapeutic target for future HIV cure strategies.

immunology↗

Development of humanized mouse and rat models with full-thickness human skin and autologous immune cells

The human skin is a major barrier for host defense against many human pathogens, with several pathogens directly targeting the skin for replication and disease. The skin is also the primary route of infection for a myriad of vector-borne diseases; thus cutaneous immune cells play a major role in modulating transmission for such infectious diseases. Several human pathogens that target the skin as a major route of infection are unable to infect traditional rodent models or recapitulate the pathogenesis in humans. It is well established that differences exist in human skin and immune cell biology compared to rodent models. Therefore, rodent (mouse and rat) models that incorporate human skin and immune cells would addressed the above discussed technical gap, and enable in vivo mechanistic studies of human host-skin pathogen interactions, and support the development of novel therapeutics. Here, we introduce the novel human Skin and Immune System (hSIS)-humanized NOD-scid IL2Rgnull (NSG) mouse and Sprague-Dawley-Rag2tm2hera Il2rgtm1hera (SRG) rat models, co-engrafted with full-thickness human fetal skin, autologous fetal lymphoid tissues, and fetal liver-derived hematopoietic stem cells. hSIS-humanized rodents support the development of adult-like, full-thickness human skin and human lymphoid tissues, and support human immune cell development. Furthermore, the engrafted human skin supports Methicillin-resistant Staphylococcus aureus infection, demonstrating the utility of these humanized rodent models in studying human disease.

immunology↗