Publications by authors named "Maito Hanai"
Hermaphroditic invertebrates and plants have a self-recognition system on the cell surface of sperm and eggs, which prevents their self-fusion and enhances non-self-fusion, thereby contributing to genetic variation. However, the system of sperm-egg recognition in mammals is under debate. To address this issue, we explored the role of major histocompatibility complex class I (MHC class I, also known as histocompatibility 2-K or H2-K and H2-D in mice) antigens by analyzing () triple-knockout () male mice with full fertility.
View Article and Find Full Text PDFIn bacteria, a polymer of inorganic phosphate (Pi) (inorganic polyphosphate; polyP) is enzymatically produced and consumed as an alternative phosphate donor for adenosine triphosphate (ATP) production to protect against nutrient starvation. In vertebrates, polyP has been dismissed as a "molecular fossil" due to the lack of any known physiological function. Here, we have explored its possible role by producing transgenic (TG) mice widely expressing Saccharomyces cerevisiae exopolyphosphatase 1 (ScPPX1), which catalyzes hydrolytic polyP degradation.
View Article and Find Full Text PDFArticle Synopsis
- The ubiquitin-proteasome system, initiated by the enzyme E1 (UBE1), plays a key role in male reproduction and is also involved in female reproduction, particularly in egg development.
- A specific inhibitor of UBE1, PYR-41, was found to negatively impact the ability of mouse eggs to develop into two-cell embryos by interfering with processes like sperm enlargement and chromosomal division after fertilization.
- The study suggests that the disruption of β-catenin localization, which is affected by the ubiquitin-proteasome system, may be a mechanism through which PYR-41 suppresses egg development, especially in relation to its interactions with sperm.
Article Synopsis
- In multicellular organisms, cellular components are constantly moved within and between cells, with exosomes serving as crucial mediators of this intercellular transportation.
- The discovery of external vesicles in plants led to the identification of structures similar to exosomes, with tetraspanins like CD9 playing key roles in processes like sperm-egg fusion in mammals.
- Recent findings suggest that various types of exosome-like vesicles may be released by both plant and animal cells, highlighting their importance in regulating various biological processes.