meiotic in Biological News

Is this the beginning of the end of plant breeding?

... combined. These divisions are normally meiotic which make pollen and egg cells and are ... without the lottery of reassortment that each meiotic division and ensuing fertilization introduces. ... homologous pairs of chromosomes while the second meiotic division is just like the mitotic di vision: the ...

Rong Li Lab probes mechanism of asymmetry in meiotic cell division

... drives chromosome movement in mammalian meiotic oocytes," said Hongbin Li, Ph.D., Senior Research ... are often related to problems during oocyte meiotic cell divisions," said Rong Li, Ph.D., ... toward a better understanding of the process of meiotic divisions and how actin generates the force to ...

Stowers Institute's Hawley Lab identifies factors responsible for restart of meiotic cycle

... of proteins that work in concert to restart the meiotic cycle of oocytes following a natural period of ... in organisms like humans, but shorter periods of meiotic arrest can be found in simpler, more easily ... in meiosis as in humans. The long period of meiotic arrest has mystified biologists for over a ...

Small RNAs can play critical roles in male infertility/contraception

... also in sperm formation. "The sex chromosome silencing in meiotic male germ cells is a well-known phenomenon, which has been termed meiotic sex chromosome inactivation. I was surprised when we first observed that ...

Oosight microscope enables embryonic stem cell breakthrough

... The Oosight allowed Mitalipovs team to clearly see and remove the meiotic spindle (and the attached genetic material) from 304 female rhesus monkey ... components of the cell, which led to his landmark discovery in 1951 of the meiotic spindle fibers in living cells. He later showed that dynamic disassembly ...

Yeast missing sex genes undergo unexpected sexual reproduction

... "This provides a new way to study sexual reproduction and how chromosomal abnormalities arise." Heitman said that Candida 's meiosis without meiotic genes may be what gives rise to the progeny with unusual numbers of chromosomes. "Or maybe the genes were lost for a reason, to provide a route to ...

New egg freezing technique offers hope to hundreds of women

... in particular to a part called the meiotic spindle which is involved in cell division. The meiotic spindle is a bundle of microtubules, some of ... movement. "Before freezing we observed meiotic spindles in 62.5% of oocytes, but in only 43.4% ...

Scientists discover role for dueling RNAs

... cells from which they originate. But in some cases, flipping the meiotic switch can be catastrophic. If a cell with only one copy of each ... into meiosis, the progeny won't survive. Fortunately, such destructive meiotic division is avoided in haploid cells because they continually produce IME4 ...

What controls stickiness of 'smart' chromosomal glue

... initial removal of cohesin from the chromosome arms, they found. In meiotic recombination, after each member of a chromosome pair has replicated to ... essential to remove cohesins from chromosome arms during the initial meiotic stages, and if you don't have recombination that does not happen ...

New clues to how sex evolves

... and the process of meiosis can be observed at every stage, as chromosomes first come together during the pairing process, then later separate during meiotic division. One result of failed pairing of X chromosomes is a high incidence of males having only one X chromosome. The observation that a mutant ...

Invitrogen Launches i-Path -- A Unique Systems Biology Platform at BIO 2005

... treatment at present, and so any that are retrieved can be donated for research. These immature oocytes are arrested in the prophase I stage, before meiotic division is complete, when the enlarged nucleus is called the germinal vesicle (GV). Bjorn Heindryckx, a PhD student at the Infertility Centre at ...

Scientists succeed in cloning human embryos from eggs matured in the lab

... treatment at present, and so any that are retrieved can be donated for research. These immature oocytes are arrested in the prophase I stage, before meiotic division is complete, when the enlarged nucleus is called the germinal vesicle (GV). Bjorn Heindryckx, a PhD student at the Infertility Centre at ...

Human Eggs Can Develop From Ovarian Surface Cells In Vitro

... team was able to produce new human oocytes in vitro. The oocytes cultured in this way are viable and went on to successfully complete the first meiotic division to become mature human eggs -- capable of being fertilized and developing into an embryo. These in vitro findings support earlier in vivo ...