Researchers in the University of Georgia's Regenerative Bioscience Center are visually capturing the first process of chromosome alignment and separation at the beginning of mouse development. The findings could lead to answers to questions concerning the mechanisms leading to birth defects and chromosome instability in cancer cells. "We've generated a model that is unique in the world," said Rabindranath De La Fuente, an associate professor in the UGA College of Veterinary Medicine. "Because we removed ATRX protein expression only in the oocyte, the female egg cell, we can now study its function at both the cellular and molecular level." 

ATRX is a protein that binds to the centromere of all chromosomes in every single cell of the body, but when it malfunctions, chromosomes cannot segregate properly and lose their structural integrity. Using the ATRX protein, the researchers developed a mouse model to learn how an embryo responds to abnormal chromosome segregation. 

In the study, published recently in the journal Development, De La Fuente and assistant professor Maria Viveiros, both in the college's department of physiology and pharmacology, have established that stability of a specialized chromosomal domain in an early embryo is absolutely vital for subsequent development and health. 

The future goal of this study is to learn about the mechanisms of chromosomal defects, helping to someday reduce the risk of chromosome instability and increase prevention through improving early prenatal care. 

There is an urgent need to develop additional non-invasive strategies concerning maternal health, Viveiros said, pointing out the classic example of how folic acid significantly reduced the risk of spina bifida "by the simple recommendation of taking a daily dose of the vitamin folic acid before and during pregnancy.

"With our unique model, by deleting the protein strictly in the female egg, we can begin to understand how maternal proteins help regulate these initial cell divisions during early development."