Gamete production and fertilization influence zygote production. While gamete production is correlated positively with body size, individual fertilization success may be a function of population density. Usually it is assumed that when high population density leads to reduced body size and gamete production, per capita zygote production is diminished. This field study of the sea urchin Diadema ...

The first cell of an animal (zygote) requires centrosomes that are assembled from paternally inherited centrioles and maternally inherited pericentriolar material (PCM) [1]. In some animals, sperm centrioles with typical ultrastructure are the origin of the first centrosomes in the zygote [2-4]. In other animals, however, sperm centrioles lose their proteins and are thought to be degenerated an...

Specification of germline and somatic cell lineages in C. elegans originates in the polarized single-cell zygote. Several cell-fate determinants are partitioned unequally along the anterior-posterior axis of the zygote, ensuring the daughter cells a unique inheritance upon asymmetric cell division. Recent studies have revealed that partitioning of the germline determinant PIE-1 and the somatic ...

Fertilization is a hallmark event of sexual reproduction marked by the fusion of male and female gamete to form zygote. It is a highly complex, yet a robust process that is intricately regulated by various signalling molecules. A healthy fertilization is determined by the quality of zygote which is contingent on the health of egg and sperm. The relationship between infertility and gametic healt...

BACKGROUND The intracytoplasmic injection of sperm raises the problem that viral elements may be transported into the oocyte by the spermatozoon or the surrounding medium. It also raises questions about how the developing zygote will behave. METHODS We used the murine model to microinject murine cytomegalovirus (MCMV) into the zygote ooplasm and followed the changes in these microinjected zyg...

Centrioles are conserved, self-replicating, microtubule-based, 9-fold symmetric subcellular organelles that are essential for proper cell division and function. Most cells have two centrioles and maintaining this number of centrioles is important for animal development and physiology. However, how animals gain their first two centrioles during reproduction is only partially understood. It is we...

In mammalian development, epigenetic modifications, including DNA methylation patterns, play a crucial role in defining cell fate but also represent epigenetic barriers that restrict developmental potential. At two points in the life cycle, DNA methylation marks are reprogrammed on a global scale, concomitant with restoration of developmental potency. DNA methylation patterns are subsequently r...

Abstract Study question What is diploid and euploid frequency of blastocysts derived from tripronuclear zygote (3PN) including a small pronucleus (2.1PN) with NGS SNP analysis? Summary answer Diploid rate the 3PN 2.1PN was 91.3%, in which euploid, aneuploid mosaic embryos were 18.7%, 61.3% 11.3%, respectively. known already A thought to be produced when two sperm enter into same oocyte during v...