Annual Review of Animal Biosciences最新文献

Selenoproteins incorporate selenocysteine (Sec), a noncanonical amino acid analogous to cysteine with selenium in place of sulfur. Sec is inserted co-translationally via a unique recoding process that redefines the UGA stop codon in selenoprotein transcripts, marked by the Sec insertion sequence (SECIS) element in the 3' untranslated region. Metazoans display striking diversity in their selenoproteomes. Although many animals, including mammals, depend on selenoproteins for critical roles in redox homeostasis and signaling, thyroid hormone metabolism, and stress responses, other lineages have lost the entire Sec pathway. We summarize the molecular biology of Sec, covering its biosynthesis, metabolism, insertion, and regulatory mechanisms. We then examine the evolutionary dynamics of selenoproteins across metazoa, including gene duplications, losses, and substitutions of Sec to cysteine. Finally, we present an updated survey of known metazoan selenoprotein families, detailing their structure, function, and phylogenetic distribution. Altogether, we offer a comprehensive view of selenoprotein evolution and function in animals.

Spontaneous cancers in client-owned dogs often closely recapitulate their human counterparts with respect to clinical presentation, histological features, molecular profiles, response and resistance to therapy, and the evolution of drug-resistant metastases. In several instances, the incorporation of dogs with cancer into the preclinical development path of cancer therapeutics has influenced outcomes by helping to establish pharmacokinetic/pharmacodynamics relationships, dose/regimen, expected clinical toxicities, and ultimately the potential for biologic activity. As our understanding regarding the molecular drivers and immune landscape of canine cancers has improved, unique opportunities have emerged to leverage this spontaneous model as a mechanism to better guide cancer drug development so that therapies likely to fail are eliminated earlier, whereas those with true potential are optimized prior to human trials. Both pets and people benefit from this approach, because it provides dogs with access to cutting-edge cancer treatments and helps to insure that people are given treatments with a greater probability of success.

This article charts the history of a scientific career that began in the plant sciences and is ending in research on the placenta-brain axis and on the developmental origins of the mammalian placenta. In the middle was the characterization of uteroferrin and interferon-τ, the role of the latter in maternal recognition of pregnancy, and the development of a commercial pregnancy test for dairy cows. The article also emphasizes the roles personal upheavals and happenchance played in shaping a professional life and dealing with an incident of scientific malfeasance that threatened it. The article concludes with a discussion of the difficulties of practicing science during the twilight years.

The transmissible spongiform encephalopathies are a group of fatal, progressive neurodegenerative disorders caused by the misfolding of prion proteins, leading to severe neuropathology and death. Since the description of scrapie in sheep several centuries ago, significant advancements have been made in understanding the spectrum of prion diseases, including bovine spongiform encephalopathy and Creutzfeldt-Jakob disease. Despite decades of research, critical gaps remain in our understanding of prion replication mechanisms, interspecies transmission, and the environmental persistence of prions. Advances in molecular imaging, including cryo-electron microscopy, have been instrumental in visualizing prion-associated aggregates in affected brain tissues, providing critical insights into their conformation and strain-specific structures. We explore the development of transmissible spongiform encephalopathy research in animals, major scientific breakthroughs, and the pressing need for innovative diagnostic and therapeutic approaches. Addressing these challenges is essential for controlling the spread of prion diseases, and reducing their impact on public health and agriculture.

Tasmanian devils are globally renowned for their calamitous decline over the past 30 years due to two contagious clonal cancers and the heroic efforts of researchers, conservationists, and the community to bring them back from the brink of extinction. Scientific investigations into the world's largest marsupial carnivore commenced in the early 1900s. This systematic review follows the changing face of scientific research into Tasmanian devils. It reflects on how science moved from biological investigations in the 1950s and 1960s, to ecological studies in the 1980s and 1990s, to the discovery of the first clonal cancer in 1996, followed by a flurry of work to understand the disease and develop a vaccine, establish and manage an insurance program, and then roll out a translocation program that alleviated small population pressures and maintained devils in the wild. Over this period, technology has changed rapidly, from camera traps to satellite collars and microsatellites to whole-genome sequencing. Through this, societal support for the species has never wavered, and the species persists in the wild.

DNA methylation was the earliest epigenetic mark discovered-it is essential for mammalian development and forms a molecular memory that can transcend generations, as in the phenomenon of genomic imprinting. Set against this long-term potential, methylation is dynamic across the life cycle, with genome-wide changes at germ-cell specification, gametogenesis, and preimplantation development accompanying major shifts in cell potency. With a tool kit of precision genetic reagents, the mouse has been a mainstay in developing mechanistic understanding of how methylation is targeted to the genome and in exploring its susceptibility to environmental factors, such as parental diet. The availability of genome sequence from many more species combined with the ability to profile methylation and other epigenetic marks in very small numbers of cells now provides rich epigenomic information from other mammals. This information has begun to reveal both similarities as well as surprising differences in the way in which methylation is patterned across the genome among mammals. Such knowledge will be critical in assessing the outcomes of interventions during assisted reproduction in human clinical practice and livestock production.

Livestock farming faces increasing demands for sustainability and improved animal welfare. Noninvasive approaches for monitoring animal health and physiology are of growing interest. Exhaled breath analysis, or exhalomics, has emerged as a promising tool for detecting volatile organic compounds and gases associated with metabolism, disease states, physiological processes, and microbiome in livestock. This review synthesizes current advancements in breath sampling and analytical technologies and evaluates applications in disease diagnostics, nutritional assessment, and physiological and microbial profiling across livestock species. Although progress is evident, key challenges remain, including sampling variability, incomplete metabolite annotation, and limited scalability for field use. Future efforts should prioritize standardizing protocols; expanding livestock-specific spectral libraries; and developing affordable, real-time sensors for on-farm deployment. Integrating exhalomics with multi-omics and artificial intelligence-driven analytics holds potential to enable earlier disease detection, improve production efficiency, and reduce environmental impacts, ultimately advancing precision livestock farming and animal welfare over the coming decade.

Recent advances in technologies that replicate specific aspects of embryogenesis in vitro by using stem cells have opened new frontiers in our understanding of the earliest steps of mammalian development and creation of promising novel assisted reproductive technologies (ARTs). We begin by summarizing the widely used ARTs in improving animal reproduction. We then explore current progress in deriving embryo-based stem cells from livestock species and highlight the latest breakthroughs in blastoid generation. Furthermore, we examine the potential applications of blastoids in domestic livestock and discuss key challenges and future directions for advancing blastoid models that closely mimic natural embryonic development.

Adult tissue regeneration is a rare phenomenon in mammals. Most mammals heal tissue through scarring, which quickly seals the wound and helps prevent blood loss and infection, but this comes at the cost of poor tissue regeneration. Regeneration is typically studied in worms, amphibians, or fish, which gives insights into the biology of respective species but provides limited translation for human therapies. However, several mammals develop adaptations, typically favored by natural selection pressures, to regenerate a specialized tissue (e.g., antlers in deer or skin in bats) or a systemically reduced scar formation that allows multiple tissues to restore their function (e.g., African spiny mice). In this review, we aim to summarize the examples of mammals that regenerate tissues and discuss potential cellular mechanisms that allow their regeneration. The future studies of these exceptional mammals can allow for a greater understanding of mammalian complexity and provide insights for future therapies.

Rodents have been the primary model for mammalian nutritional physiology for decades. Despite an extensive body of literature, controversies remain around the effects of specific nutrients and total energy intake on several aspects of nutritional biology, even in this well-studied model. One approach that is helping to bring clarity to the field is the geometric framework for nutrition (GFN). The GFN is a multidimensional paradigm that can be used to conceptualize nutrition and nutritional effects, design experiments, and interpret results. To date, more than 30 publications have applied the GFN to data from rodent models of nutrition. Here we review the major conclusions from these studies. We pay particular attention to the effects of macronutrients on satiety, glucose metabolism, lifespan and the biology of aging, reproductive function, immune function, and the microbiome. We finish by highlighting several knowledge gaps that became evident upon reviewing this literature.