Principles of intracellular protein synthesis and protein degradation remain to be among the
most challenging questions of modern cell biology. Proteolysis plays an important role in …

Chromosome segregation errors in human oocytes lead to aneuploid embryos that cause
infertility and birth defects. Here we provide an overview of the chromosome-segregation …

During mammalian oocyte maturation there are marked changes in the distribution of
mitochondria that supply the majority of the cellular ATP. Such redistribution of mitochondria …

Despite the success of embryo cyropreservation, routine oocyte freezing has proved elusive
with only around 200 children born since the first reported birth in 1986. The reason for the …

In contrast to the preimplantation mammalian embryo, it has been notoriously difficult to
cryopreserve the metaphase II oocyte. The ability to store oocytes successfully at− 196° C …

Fertilization in all species studied to date induces an increase in the intracellular
concentration of free calcium ions ([Ca2+] i) within the egg. In mammals, this [Ca2+] i signal …

Mammalian eggs arrest at metaphase of the second meiotic division (MetII). Sperm break
this arrest by inducing a series of Ca 2+ spikes that last for several hours. During this time …

It has been known for some time that mammalian eggs are activated by a series of
intracellular calcium oscillations that occur shortly after sperm egg membrane fusion. Recent …

Objective To assess the effect of two assisted oocyte activation (AOA) protocols with the use
of two calcium (Ca 2+) ionophores, ionomycin and A23187 (calcimycin), on the intracellular …

BACKGROUND Somatic cell nuclear transfer (SCNT) requires cytoplast-mediated
reprogramming of the donor nucleus. Cytoplast factors such as maturation promoting factor …