Nejvíce citovaný článek - PubMed ID 31530150
Classical evolutionary theories propose tradeoffs among reproduction, damage repair and lifespan. However, the specific role of the germline in shaping vertebrate aging remains largely unknown. In this study, we used the turquoise killifish (Nothobranchius furzeri) to genetically arrest germline development at discrete stages and examine how different modes of infertility impact life history. We first constructed a comprehensive single-cell gonadal atlas, providing cell-type-specific markers for downstream phenotypic analysis. We show here that germline depletion-but not arresting germline differentiation-enhances damage repair in female killifish. Conversely, germline-depleted males instead showed an extension in lifespan and rejuvenated metabolic functions. Through further transcriptomic analysis, we highlight enrichment of pro-longevity pathways and genes in germline-depleted male killifish and demonstrate functional conservation of how these factors may regulate longevity in germline-depleted Caenorhabditis elegans. Our results, therefore, demonstrate that different germline manipulation paradigms can yield pronounced sexually dimorphic phenotypes, implying alternative responses to classical evolutionary tradeoffs.
Pituitary hormones play a central role in shaping vertebrate life history events, including growth, reproduction, metabolism, and aging. The regulation of these traits often requires precise control of hormone levels across diverse timescales. However, fine tuning circulating hormones in-vivo has traditionally been experimentally challenging. Here, using the naturally short-lived turquoise killifish (N. furzeri), we describe a high-throughput platform that combines loss- and gain-of-function of peptide hormones. Mutation of three primary pituitary hormones, growth hormone (gh1), follicle stimulating hormone (fshb), and thyroid stimulating hormone (tshb), alters somatic growth and reproduction. Thus, suggesting that while the killifish undergoes extremely rapid growth and maturity, it still relies on vertebrate-conserved genetic networks. As the next stage, we developed a gain-of-function vector system in which a hormone is tagged using a self-cleavable fluorescent reporter, and ectopically expressed in-vivo through intramuscular electroporation. Following a single electroporation, phenotypes, such as reproduction, are stably rescued for several months. Notably, we demonstrate the versatility of this approach by using multiplexing, dose-dependent, and doxycycline-inducible systems to achieve tunable and reversible expression. In summary, this method is relatively high-throughput, and facilitates large-scale interrogation of life-history strategies in fish. Ultimately, this approach could be adapted for modifying aquaculture species and exploring pro-longevity interventions.
In humans and other vertebrates, a pea-size gland at the base of the brain called the pituitary gland, produces many hormones that regulate how individuals grow, reproduce, and age. Three of the most prominent hormones are known as the growth hormone, the follicle-stimulating hormone, and the thyroid-stimulating hormone. It is important that the body precisely controls the levels of these hormones throughout an individual’s life. One way researchers can investigate how hormones and other molecules work is to artificially alter the levels of the molecules in living animals. However, this has proved to be technically challenging and time-consuming for pituitary gland hormones. Moses et al. studied the growth hormone, follicle-stimulating hormone, and thyroid-stimulating hormone in the turquoise killifish, a small fish that grows and matures more rapidly than any other vertebrate research model. The experiments revealed that mutant fish lacking one of the three primary pituitary hormones were smaller, took longer to reach maturity, or were completely sterile. This suggests these three hormones play a similar role in killifish as they do in other vertebrates. The team then developed a new experimental platform to precisely control the levels of the three hormones in killifish. Genes encoding individual hormones were expressed in the muscles of the mutant fish, effectively making the muscles a ‘factory’ for producing that hormone. Treating mutant fish this way once was enough to restore growth and to fully return reproduction to normal levels for several months. Moses et al. also demonstrated that it is possible to use this platform to express more than one hormone gene at a time and to use drugs to switch hormone production on and off in a reversible manner. For example, this reversible approach made it possible to effectively adjust fertility levels. The new platform developed in this work could be adapted for modifying a variety of traits in animals to explore how they impact health and longevity. In the future, it may also have other applications, such as optimizing how farmed fish grow and reproduce and regulating hormone levels in human patients with hormone imbalances.
- Klíčová slova
- CRISPR, aging, aquaculture, developmental biology, genome editing, nothobranchius furzeri, peptide hormones, reproduction, somatic growth,
- MeSH
- dlouhověkost MeSH
- Fundulidae * MeSH
- hypofyzární hormony MeSH
- peptidové hormony * MeSH
- růstový hormon metabolismus MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- hypofyzární hormony MeSH
- peptidové hormony * MeSH
- růstový hormon MeSH
The present study was designed to evaluate sperm phenotypic variables during in vivo and in vitro storage following multiple sperm stripping in common carp (Cyprinus carpio L.). Each male was injected 3 times with carp pituitary 3 days apart. Sperm was stored in vivo in the body cavity for 0.5 days (Fresh sperm) and 3 days (Old sperm) after hormonal stimulation. Then sperm was collected and diluted with a carp extender at a ratio of 1:1, and stored in vitro on ice for 0, 3, and 6 days. The phenotypic parameters, including the number of total motile spermatozoa, number of fast motile spermatozoa, number of motile spermatozoa, percentage of fast motile spermatozoa, and percentage of spermatozoa motility were the major components of principal component analysis (PCA). In general, Fresh sperm from the first stripping showed slightly better quality than Old sperm from the second and third stripping, especially in the phenotypic parameters of a number of total spermatozoa and a number of total motile spermatozoa (P < 0.05). The highest kinetic and quantitative spermatozoa variables were obtained in Fresh and Old sperm just after sperm collection (0-day storage in vitro), and then they were decreased during the period of in vitro storage up to 6 days (P < 0.05). However, the fertilization, hatching, and malformation rates from Fresh sperm were similar compared with the Old sperm. Sperm could be stripped 0.5 days post hormonal treatment and stored in vitro up to 6 days with good fertilization performance (fertility, hatching, and malformation rates were 92.5%, 91.5%, and 1.3%, respectively). Therefore, our results suggested that multiple hormonal treatments with multiple stripping could be used in artificial reproduction in common carp.
- Klíčová slova
- Common carp, In vitro, In vivo, Sperm storage, Spermatozoa aging,
- MeSH
- kapři * MeSH
- kryoprezervace metody MeSH
- led MeSH
- motilita spermií fyziologie MeSH
- sperma fyziologie MeSH
- spermie fyziologie MeSH
- stárnutí MeSH
- uchování spermatu * metody MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- led MeSH
