PRESS-NEWS.org - Press Release Distribution
PRESS RELEASES DISTRIBUTION

Researchers identify traffic cop for meiosis--with implications for fertility and birth defects

2013-10-02
(Press-News.org) Researchers at New York University and the Whitehead Institute for Biomedical Research have identified the mechanism that plays "traffic cop" in meiosis—the process of cell division required in reproduction. Their findings, which appear in the journal eLife, shed new light on fertility and may lead to greater understanding of the factors that lead to birth defects.

"We have isolated a checkpoint that is necessary for a genome's viability and for normal development," said Andreas Hochwagen, an assistant professor in NYU's Department of Biology, who co-authored the paper with Hannah Blitzblau, a researcher at the Whitehead Institute for Biomedical Research. "Without this restraining mechanism, chromosomes can end up irreversibly broken during meiosis."

The paper may be downloaded here: http://dx.doi.org/10.7554/eLife.00844.

Most cells in an organism contain two sets of chromosomes, one inherited from the mother and the other from the father. However, sexual reproduction relies on the production of gametes — eggs and sperm —that contain only one set of chromosomes. These are produced through a specialized form of cell division—meiosis.

In this process, maternal and paternal versions of each chromosome pair up and swap sections of their DNA through a process known as homologous recombination—a "reshuffling" that gives rise to chromosomes with new combinations of maternal and paternal genes. This is followed by cell division.

However, in order for normal development to occur, chromosomes must be replicated prior to their reshuffling. The disruption of this process jeopardizes reproduction and can spur a range of birth defects, notably Down syndrome.

Blitzblau and Hochwagen sought to determine what coordinates these processes to ensure they occur in proper order. Doing so would offer insights into how deviations from normal functionality could affect fertility and result in birth defects.

To do so, they examined budding yeast--a model organism in cell biology because its chromosome replication and regulation are similar to that of humans.

Through a series of manipulations, in which the researchers inhibited the activity of individual proteins, they found two enzymes that were necessary for meiosis: Mec1, which is similar to ATR, known to suppress tumors in humans, and DDK, which is a vital coordinator of chromosome reshuffling.

Specifically, they found that Mec1 senses when chromosomes are being replicated and transmits a molecular "wait" signal to DDK. In this way, Mec1 acts like a traffic cop that allows chromosome replication to finish without interruption, before giving DDK the ok to begin the reshuffling.

### The study was funded by grants from the National Institutes of Health (R01 GM088248), the Charles A King Trust, and the Alexander and Margaret Stewart Trust.


ELSE PRESS RELEASES FROM THIS DATE:

'Walking droplets'

2013-10-02
VIDEO: A droplet of silicone oil bounces in place on a vibrating fluid bath. Click here for more information. WASHINGTON, D.C. Oct. 1, 2013 -- A research team led by Yves Couder at the Université Paris Diderot recently discovered that it's possible to make a tiny fluid droplet levitate on the surface of a vibrating bath, walking or bouncing across, propelled by its own wave field. Surprisingly, these walking droplets exhibit certain features previously thought to be exclusive to ...

TGen-led study identifies genes associated with unhealthy liver function

2013-10-02
PHOENIX, Ariz. — Oct. 1, 2013 — A groundbreaking study of nearly 2,300 extremely obese diabetes patients, led by the Translational Genomics Research Institute (TGen), has identified genes associated with unhealthy liver function. This is believed to be the nation's first large-scale genome-wide association study in overweight patients with diabetes. Results of the study, done in conjunction with the Geisinger Health System, will be presented at the 64th annual meeting of the American Association for the Study of Liver Diseases Nov. 1-5 at the Walter E. Washington Convention ...

Researchers find that drinking fluoridated water gives no additional risks for hip fractures

2013-10-02
Alexandria, Va., USA – Today, the International and American Associations for Dental Research (IADR/AADR) published a paper titled "Estimated Drinking Water Fluoride Exposure and Risk of Hip Fracture: A Cohort Study." In this study a team of researchers, led by Peggy Näsman, Karolinska Institute, Department of Dental Medicine, Stockholm, Sweden, investigated possible adverse health effects on bone tissue from drinking fluoridated water. The study included a large cohort of Swedish residents chronically exposed to various fluoride levels, with the hypothesis of a possible ...

Solar power's future brawl

2013-10-02
WASHINGTON, D.C. Oct. 1, 2013 -- A trio of researchers at North Dakota State University and the University of South Dakota have turned to computer modeling to help decide which of two competing materials should get its day in the sun as the nanoscale energy-harvesting technology of future solar panels -- quantum dots or nanowires. Andrei Kryjevski and his colleagues, Dimitri Kilin and Svetlana Kilina, report in AIP Publishing's Journal of Renewable and Sustainable Energy that they used computational chemistry models to predict the electronic and optical properties of ...

Rensselaer researchers propose new theory to explain seeds of life in asteroids

2013-10-02
Troy, N.Y. – A new look at the early solar system introduces an alternative to a long-taught, but largely discredited, theory that seeks to explain how biomolecules were once able to form inside of asteroids. In place of the outdated theory, researchers at Rensselaer Polytechnic Institute propose a new theory – based on a richer, more accurate image of magnetic fields and solar winds in the early solar system, and a mechanism known as multi-fluid magneto-hydrodynamics – to explain the ancient heating of the asteroid belt. Although today the asteroid belt between Mars ...

Renal risk index: A clinical tool to predict the risk of end-stage renal disease

2013-10-02
Ann Arbor, Mich. — End-stage renal disease is one of the major public health problems among solid organ transplant recipients that is associated with death after transplant and high cost of care. Using the national data of 43,514 liver transplant recipients, researchers at University of Michigan researchers in collaboration with Arbor Research Collaborative for Health created and validated a risk score called renal risk index based upon the liver transplant recipient's characteristics at the time of transplant to predict the post- transplant end stage renal disease. ...

Out-of-pocket medical spending will drop for many under Affordable Care Act, study finds

2013-10-02
Out-of-pocket medical expenses will decline for most consumers who become newly insured or change their source of health insurance under the federal Affordable Care Act, according to a new RAND Corporation study. The study found that overall the Affordable Care Act will have a varied impact on health spending by individuals and families, depending primarily on their income and whether they would have been uninsured in 2016 without the program. People who will be newly insured and do not qualify for government subsidies are those who are most likely to see increased ...

New genetic discovery could reduce the guesswork in drug dosing

2013-10-02
COLUMBUS, Ohio – The discovery of genetic differences affecting up to a third of the population could take the guesswork out of prescribing the correct dose of 25 percent of drugs currently on the market, researchers say. The scientists found two genetic variants that alter the activity level of an enzyme responsible for processing, or metabolizing, drugs ranging from the painkiller codeine to the breast cancer drug tamoxifen. The Ohio State University researchers who found these differences say that pending additional research, the variants are good candidates for ...

Notre Dame study: The face is the focus for a person wielding a gun

2013-10-02
A person wielding a gun focuses more intently on the face of an opponent with a gun, presumably to try to determine that person's likelihood of pulling the trigger, according to a new study that builds on gun-in-hand research from the University of Notre Dame. Notre Dame Associate Professor of Psychology James Brockmole, who specializes in human cognition and how the visual world guides behavior, conducted the research at Notre Dame with Adam Biggs, currently a post-doctoral fellow in the Duke Institute for Brain Sciences and the Center for Cognitive Neuroscience, and ...

Lactation may be linked to aggressive cancer in Mexican women

2013-10-02
Scientific data suggest that a woman reduces her risk of breast cancer by breastfeeding, having multiple children and giving birth at a younger age. A study led by the University of California, San Diego School of Medicine and recently published online by Cancer Epidemiology, Biomarkers & Prevention, indicates that women of Mexican descent may not fit that profile. In fact, results suggest that women of Mexican descent with more children and those who breastfeed are more likely to be diagnosed with an aggressive form of breast cancer. During the four-year Ella Binational ...

LAST 30 PRESS RELEASES:

Drones reveal extreme coral mortality after bleaching

New genetic finding uncovers hidden cause of arsenic resistance in acute promyelocytic leukemia

Native habitats hold the key to the much-loved smashed avocado’s future

Using lightning to make ammonia out of thin air

Machine learning potential-driven insights into pH-dependent CO₂ reduction

Physician associates provide safe care for diagnosed patients when directly supervised by a doctor

How game-play with robots can bring out their human side

Asthma: patient expectations influence the course of the disease

UNM physician tests drug that causes nerve tissue to emit light, enabling faster, safer surgery

New study identifies EMP1 as a key driver of pancreatic cancer progression and poor prognosis

XPR1 identified as a key regulator of ovarian cancer growth through autophagy and immune evasion

Flexible, eco-friendly electronic plastic for wearable tech, sensors

Can the Large Hadron Collider snap string theory?

Stuckeman professor’s new book explores ‘socially sustainable’ architecture

Synthetic DNA nanoparticles for gene therapy

New model to find treatments for an aggressive blood cancer

Special issue of Journal of Intensive Medicine analyzes non-invasive respiratory support

T cells take aim at Chikungunya virus

Gantangqing site in southwest China yields 300,000-year-old wooden tools

Forests can’t keep up: Adaptation will lag behind climate change

Sturgeon reintroduction initiative yields promising first-year survival rate

Study: Babies’ poor vision may help organize visual brain pathways

Research reveals Arctic region was permafrost-free when global temperatures were 4.5˚ C higher than today

Novel insights into chromophobe renal cell carcinoma biology and potential therapeutic strategies

A breakthrough in motor safety: AI-powered warning system enhances capability to uncover hidden winding faults

Research teases apart competing transcription organization models

Connect or reject: Extensive rewiring builds binocular vision in the brain

Benefits and risks: informal use of antibiotics to prevent sexually transmitted infections on the rise in key populations in the Netherlands

New molecular tool sheds light on how cancer cells repair telomeres

First large-scale stem cell bank enables worldwide studies on genetic risk for Alzheimer’s disease

[Press-News.org] Researchers identify traffic cop for meiosis--with implications for fertility and birth defects