Navigation Links
Stowers Institute's Hawley Lab identifies factors responsible for restart of meiotic cycle
Date:12/4/2007

The Stowers Institutes Hawley Lab has identified a pair of proteins that work in concert to restart the meiotic cycle of oocytes following a natural period of dormancy.

The Hawley Lab has described the dual actions of these two proteins as the Sleeping Beauty Kiss that awakens the long-dormant egg, allowing for production of a mature oocyte ready for fertilization. The findings appear in the Dec. 4, 2007 issue of PLoS Biology.

The long period of dormancy that interrupts the process that parses out the correct number of chromosomes is characteristic of female meiosis. The cells that will become oocytes in human females develop during fetal development and begin the actual process of meiosis before birth, but the oocytes remain in a suspended state until the female reaches sexual maturity.

Extended periods of dormancy may last many years in organisms like humans, but shorter periods of meiotic arrest can be found in simpler, more easily studied species like the fruit fly the model used by the Hawley Lab in this work. In the fruit fly, oocyte development is arrested for 3-4 days at exactly the same point in meiosis as in humans.

The long period of meiotic arrest has mystified biologists for over a century because it raises the question of just how the sleeping oocyte is reawakened. The Hawley Lab addressed this question and determined that there are two molecular solutions at play: the controlled expression of a protein that restarts the cell cycle and the inactivation of an inhibitory protein that had previously prevented the restart of meiosis.

This work led us to the conclusion that the restart of the meiotic cycle in Drosophila depends on two mechanisms, said Youbin Xiang, Ph.D., Research Specialist II and first author on the paper. First, the controlled expression of an activator, known as Polo kinase, and second, the presence of a regulatory protein called Matrimony, which binds to and physically inactivates Polo.

It takes the oocyte several days to build-up enough Polo kinase to properly restart meiosis, and the newly made Polo must remain inactive until a proper level has been reached. Matrimony serves exactly this function by inhibiting Polo kinase. However, at the proper point in oocyte development, Matrimony is destroyed releasing a sudden surge of active Polo kinase. It is this precisely timed release of active Polo kinase that restarts meiosis.

Matrimony is the first known protein inhibitor of Polo kinase, explains R. Scott Hawley, Ph.D., Investigator, and senior author on the paper. The excess of Matrimony prior to the time of normal meiotic restart keeps Polo inactive. However, the destruction of Matrimony at the appropriate time releases active Polo, permitting a properly controlled restart of meiotic progression.

The long-term implications of this work for human health and biology lie in a better understanding of how eggs are matured and released, knowledge that will have profound implications for treating infertility. Additionally, Polo kinase is strongly expressed in many types of tumor cells, so identifying a specific inhibitor for this protein may aid in the development of improved drugs for treating cancer.


'/>"/>

Contact: Marie Jennings
mfj@stowers-institute.org
816-926-4015
Stowers Institute for Medical Research
Source:Eurekalert

Related biology news :

1. Stowers Institutes Xie Lab demonstrates dual intrinsic and extrinsic control of stem cell aging
2. Study identifies warning signs of pregnancy danger
3. Study identifies genetic risk factor for rheumatoid arthritis, lupus
4. Study by Pittsburgh researchers identifies possible vaccine target for chlamydia
5. Breakthrough research identifies how cells from pigs may cure diabetes
6. Smithsonian identifies invasive crab species in Panama Canal expansion area
7. Smithsonian identifies invasive crab species in Panama Canal expansion area
8. New technology identifies warped fingerprints at warp speed
9. Study identifies pathway required for normal reproductive development
10. St. Jude identifies the specific cell that causes eye cancer, disproving long-held theory
11. Scientists show that mitochondrial DNA variants are linked to risk factors for type 2 diabetes
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:4/11/2017)... April 11, 2017 Crossmatch®, a globally-recognized ... solutions, today announced that it has been awarded ... Projects Activity (IARPA) to develop next-generation Presentation Attack ... "Innovation has been a driving force within ... will allow us to innovate and develop new ...
(Date:4/5/2017)... 5, 2017  The Allen Institute for Cell Science ... a one-of-a-kind portal and dynamic digital window into the ... the first application of deep learning to create predictive ... lines and a growing suite of powerful tools. The ... and future publicly available resources created and shared by ...
(Date:3/30/2017)... 30, 2017  On April 6-7, 2017, Sequencing.com will ... hackathon at Microsoft,s headquarters in ... focus on developing health and wellness apps that provide ... the Genome is the first hackathon for personal ... largest companies in the genomics, tech and health industries ...
Breaking Biology News(10 mins):
(Date:10/11/2017)... USA (PRWEB) , ... October 11, 2017 , ... ComplianceOnline’s ... take place on 7th and 8th June 2018 in San Francisco, CA. The Summit ... as well as several distinguished CEOs, board directors and government officials from around the ...
(Date:10/11/2017)... ... 2017 , ... A new study published in Fertility and ... in vitro fertilization (IVF) transfer cycles. The multi-center matched cohort study ... comparing the results from the fresh and frozen transfer cohorts, the authors of ...
(Date:10/10/2017)... ... October 10, 2017 , ... Dr. Bob Harman, founder and CEO of ... Rotary Club. The event entitled “Stem Cells and Their Regenerative Powers,” ... Dr. Harman, DVM, MPVM was joined by two human doctors: Peter B. Hanson, ...
(Date:10/9/2017)... 9, 2017  BioTech Holdings announced today identification ... its ProCell stem cell therapy prevents limb loss ... Company, demonstrated that treatment with ProCell resulted in ... as compared to standard bone marrow stem cell ... in reduction of therapeutic effect.  ...
Breaking Biology Technology: