Learn More
Membrane fusion is an essential step in the encounter of two nuclei from sex cells-sperm and egg-in fertilization. However, aside from the involvement of two molecules, CD9 and Izumo, the mechanism of fusion remains unclear. Here, we show that sperm-egg fusion is mediated by vesicles containing CD9 that are released from the egg and interact with sperm. We(More)
The conventional Δ5 and Δ4 steroidogenic pathways mediate androgen production in females. While multiple non-conventional pathways to dihydrotestosterone (DHT) have recently been postulated in humans, the functional significance of these pathways remains to be elucidated. The aim of this study was to clarify the origin of androgens in healthy women and in(More)
Diapause is most often observed in insects and is a physiologically dormant state different from other types of dormancy, such as hibernation. It allows insects to survive in harsh environments or extend longevity. In general, larval, pupal, or adult non-diapausing insects possess an innate immune system preventing the invasion of microorganisms into their(More)
Introducing a point mutation is a fundamental method used to demonstrate the roles of particular nucleotides or amino acids in the genetic elements or proteins, and is widely used in in vitro experiments based on cultured cells and exogenously provided DNA. However, the in vivo application of this approach by modifying genomic loci is uncommon, partly due(More)
BACKGROUND MAMLD1 is known to be a causative gene for hypospadias. Although previous studies have indicated that MAMLD1 mutations result in hypospadias primarily because of compromised testosterone production around the critical period for fetal sex development, the underlying mechanism(s) remains to be clarified. Furthermore, although functional studies(More)
Although recent studies in patients with paternal uniparental disomy 14 [upd(14)pat] and other conditions affecting the chromosome 14q32.2 imprinted region have successfully identified underlying epigenetic factors involved in the development of upd(14)pat phenotype, several matters, including regulatory mechanism(s) for RTL1 expression, imprinting status(More)
When a sperm and oocyte unite into one cell upon fertilization, membranous fusion between the sperm and oocyte occurs. In mice, Izumo1 and a tetraspanin molecule CD9 are required for sperm-oocyte fusion as one of the oocyte factors, and another tetraspanin molecule CD81 is also thought to involve in this process. Since these two tetraspanins often form a(More)
Tetraspanin CD81 is closely homologous in amino acid sequence with CD9. CD9 is well known to be involved in sperm-egg fusion, and CD81 has also been reported to be involved in membrane fusion events. However, the function of CD81 as well as that of CD9 in membrane fusion remains unclear. Here, we report that disruption of the mouse CD81 gene led to a(More)
Msx1 and Msx2 genes encode the homeodomain transcription factors. Several gene knockout mice and expression studies suggest that they possess functionally redundant roles in embryogenesis. In this study, we revealed that Msx1 and Msx2 were expressed during ventral body wall formation in an overlapping manner. Msx1/Msx2 double-mutant mice displayed embryonic(More)
In multicellular organisms, cellular components are constantly translocated within cells and are also transported exclusively between limited cells, regardless of their physical distance. Exosomes function as one of the key mediators of intercellular transportation. External vesicles were identified 50 years ago in plants and now reconsidered to be(More)