BioEssays最新文献

The characteristics of the last eukaryotic common ancestor (LECA) population and the root of the eukaryotic tree have been coming into focus lately. However, the trajectory taking the host, related to present-day Asgard archaea and the endosymbiont, related to present-day alphaproteobacteria, toward such fully integrated and complex organisms is still unclear. Here I marshal recent evidence supporting the early arrival of the “mitochondrion-to-be”, setting up the evolutionary dynamic for a series of mutual adaptations leading to eukaryotes. Upon critical analysis of some presuppositions in phylogenomic reconstructions of eukaryogenesis, I again propose that pre-symbiosis, efficient ATP generation, internal reactive oxygen species (ROS) formation and enhanced retention of genes supplied by horizontal gene transfer (HGT) interdependently allowed this unique transformation to occur.

Breathing is a vital, continuous behavior that maintains physiological homeostasis, yet it is also remarkably flexible—modulated by volitional, emotional, and behavioral states. This review highlights recent advances in understanding how distributed neural circuits, particularly in the ventrolateral medulla and dorsolateral pons, integrate both homeostatic and non-homeostatic influences on respiratory control. We examine how higher-order brain regions interact with brainstem rhythm generators such as the preBötzinger complex, emphasizing a dynamic, state-dependent framework for respiratory regulation. Once considered a reflexive brainstem function, breathing is now recognized as the emergent output of interconnected networks that flexibly adapt rhythm and pattern based on internal state, behavior, and environmental context. Grasping this complexity is critical for understanding both the normal versatility and pathological vulnerability of respiratory control.

In this report, we summarize the outcome of a consultation session held in January 2024 appraising adopted attitudes within scientific research. This Equality, Diversity & Inclusion (EDI) Sandpit was a collaboration between interdisciplinary researchers from the ECMage (Extracellular Matrix [ECM] ageing across the life course interdisciplinary research network) and BLAST (Building Links in Ageing Science & Translation) networks, both part of the UK Ageing Networks, and the lifETIME (Engineered Tissues for Discovery, Industry and Medicine) Centre for Doctoral Training. Statements representing previously prevalent patterns of thinking that could influence research practice were put to delegate teams to discuss in relation to social and cultural behaviors that have been adopted over the years. Discussions focused on five themes across two main categories, aiming to identify and understand areas where change is needed, as well as to offer suggestions on how best to concentrate efforts to make the most impact.

Vertebrate gonadal function is regulated by pituitary gonadotropins, follicle-stimulating hormone (FSH) and luteinizing hormone (LH). These hormones are considered to be regulated by hypothalamic factor(s). Since the discovery of gonadotropin-releasing hormone (GnRH) in mammals, which stimulates the secretion of both FSH and LH, GnRH had been believed to be the sole gonadotropin-releasing hormone in vertebrates for more than 5 decades. However, recent studies have identified an alternative primary regulator of FSH in teleosts, leading to the hypothesis that FSH and LH are regulated by different factors in teleosts (dual GnRH model). This contrasts with the situation in mammals, where a single GnRH regulates both hormones (solo GnRH model). Importantly, although underlying mechanisms likely differ, both teleosts and mammals reproduce efficiently and have convergently evolved similar phenomena, including steroid feedback regulation. In this review, by comparing these taxa, we summarize mechanistic differences and propose an evolutionary scenario based on current experimental evidence.

The timely release of chemical messengers is a crucial step in cell-to-cell communication. Does this release occur as a passive diffusion from the donor membrane or it is actively regulated? A series of studies indicated that chemical messengers’ secretion is “sub-quantal”. This mode of secretion demands a strongly regulated release mechanism and calls for a thorough characterization of the release sites. When secretory vesicles fuse with the plasma membrane, ephemeral fusion pores serve as the first aqueous connection between the lumen of secretory vesicle and the cell exterior through which chemical messengers are released. Here, we discuss the molecular players that directly regulate fusion pore properties. This has consequences in controlling the amount of chemical messengers’ secretion, hence controlling the quantal size. A thorough understanding of the role of regulatory factors in controlling quantal size can help design potent therapeutics to alter vesicular secretion under pathological conditions.