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Archive - Dec 14, 2014

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Baby Cells Learn to Communicate Using the Lsd1 Protein

We would not expect a baby to join a team or participate in social situations that require sophisticated communication. Yet, most developmental biologists have assumed that young cells, only recently born from stem cells and known as "progenitors," are already competent at inter-communication with other cells. New research from Carnegie's Dr. Allan Spradling and postdoctoral fellow Dr. Ming-Chia Lee shows that infant cells have to go through a developmental process that involves specific genes before they can take part in the group interactions that underlie normal cellular development and keep our tissues functioning smoothly. The existence of a childhood state where cells cannot communicate fully has potentially important implications for our understanding of how gene activity on chromosomes changes both during normal development and in cancerous cells. The work is published in Genes and Development. The way that the molecules that package a cell's chromosomes are organized in order to control gene activity is known as the cell's "epigenetic state." The epigenetic state is fundamental to understanding Dr. Spradling’s and Dr. Lee's findings. To developmental biologists, changes in this epigenetic state ultimately explain how the cell's properties are altered during tissue maturation. "In short, acquired epigenetic changes in a developing cell are reminiscent of the learned changes the brain undergoes during childhood," Dr. Spradling explained. "Just as it remains difficult to map exactly what happens in a child's brain as it learns, it is still very difficult to accurately measure epigenetic changes during cellular development. Not enough cells can usually be obtained that are at precisely the same stage for scientists to map specific molecules at specific chromosomal locations." Dr. Lee and Dr.

Landmark Mitochonrdrial Studies at UW-Madison Continue 60-Year Tradition

Dr. Frederick Crane was a researcher under Dr. David E. Green in the mid-1950s, during the early days of the University of Wisconsin-Madison (UW-Madison) Enzyme Institute, when he made his defining discovery. The lab group was on a mission to determine, bit by bit, how mitochondria -- the power plants of cells -- generate the energy required to sustain life. What Dr. Crane found, a compound called coenzyme Q, was a missing piece of the puzzle and became a major part of the legacy of mitochondrial research at UW-Madison. But it was no accident. "It was the result of a long train of investigation into a mechanism of, and compounds involved in, biological energy conversion," Dr. Crane wrote in a 2007 review article of his discovery. Almost six decades later, that "long train" has grown even longer. Dr. Dave Pagliarini, a UW-Madison assistant professor of biochemistry, has established a new laboratory studying these dynamic organelles, the mitochondria. He recently published two studies shedding more light on coenzyme Q and how it's made, one in PNAS online on October 22, 2014. and another on December 11, 2014 in Molecular Cell. "Mitochondria are tiny structures in nearly all of our cells that are essential for producing our cellular energy and that house a wide array of metabolic processes," Dr. Pagliarini says. "When mitochondria don't work properly, many different human diseases can arise." These include cerebellar ataxia, certain kidney diseases, and severe childhood-onset multisystemic diseases. Coenzyme Q deficiency is a hallmark of these diseases, but scientists aren't sure why. "Nearly 60 years later, there is still much we don't know about how mitochondria make coenzyme Q and that has complicated our ability to target this pathway therapeutically," Dr. Pagliarini says.

Male and Female Breast Cancers Are Not Identical

Results of the EORTC10085/TBCRC/BIG/NABCG International Male Breast Cancer Program conducted in both Europe and in the United States and presented at the 2014 San Antonio Breast Cancer Symposium December 9-13, 2014. found significant improvement in survival for men with breast cancer, but this improvement was not as good as that observed for women. The study, which included 1822 men treated for breast cancer between 1990 and 2010, provides much needed information about the clinical and biological characteristics of male breast cancer. Dr. Fatima Cardoso of the Champalimaud Clinical Center in Lisbon, Portugal, and coordinator of this study says, "This study aims to characterize the biology of this rare disease; only with this crucial knowledge will men with breast cancer be properly treated in the future, which will definitely improve both their survival and quality of life." Of all cancers diagnosed in males, breast cancer accounts for less than one percent, and male breast cancer also accounts for less than one percent of all breast cancer diagnoses. There are, however, African countries reporting a high incidence of male breast cancer, and these include Uganda, 5%, and Zambia, 15%. Nevertheless, even though it is considered a rare disease, male breast cancer remains frequently lethal. In 2013 estimates indicated just 2,240 new cases of male breast cancer in the United States yet, alarmingly, 410 deaths. Today, male breast cancer is not well understood, and the best way to treat this disease is not yet known. Currently, treatment strategies for men afflicted with this disease are based on those treatmemts that have been used successfully for women, and research on the differences between men and women regarding the characteristics of this disease has been sorely needed.

Viral Fossil Study on Birds Finds Fewer Infections Than in Mammals

In a contribution to an extraordinary international scientific collaboration, the University of Sydney found that genomic 'fossils' of past viral infections are up to thirteen times less common in birds than mammals. "We found that only five viral families have left a footprint in the bird genome (genetic material) during evolution. Our study therefore suggests that birds are either less susceptible to viral invasions or purge them more effectively than mammals," said Professor Edward Holmes, from the University of Sydney's Charles Perkins Centre, School of Biological Sciences and Sydney Medical School. "The results shed light on virus-host interactions across 100 million years of bird evolution." Professor Holmes is one of 200 scientists worldwide who have taken part in the ambitious scientific effort to sequence, assemble and compare the full genomes of 48 bird species. After four years of collaboration the findings are published in Science and simultaneously in associated publications on December 12, 2014. Their insights include how birds arrived at the spectacular biodiversity of more than 10,000 species. Professor Eddie Holmes is an author on the first flagship paper published inScience. "This exciting flagship paper presents a comprehensive history of how bird genomes have evolved along with a new family tree for birds. It also briefly covers our research on viral fossils in birds, covered in more detail in an article published (online on December 11, 2014) in Genome Biology," said Professor Holmes. "One of the most striking findings is the small size of bird genomes, and the small number of fossil viruses seems to match this," said Dr. Holmes. Together with his postdoctoral student Dr.

New Theory on Evolution of the Eukaryotic Cell

As a fundamental unit of life, the cell is central to all of biology. Better understanding of how complex cells evolved and work promises new revelations in areas as diverse as cancer research and developing new crop plants. But deep thinking on how the eukaryotic cell came to be is astonishingly scant. Now, however, a bold new idea of how the eukaryotic cell and, by extension, all complex life came to be is giving scientists an opportunity to re-examine some of biology's key dogma. All complex life -- including plants, animals, and fungi -- is made up of eukaryotic cells, cells with a nucleus and other complex internal machinery used to perform the functions an organism needs to stay alive and healthy. Humans, for example, are composed of 220 different kinds of eukaryotic cells -- which, working in groups, control everything from thinking and locomotion to reproduction and immune defense. Thus, the origin of the eukaryotic cell is considered one of the most critical evolutionary events in the history of life on Earth. Had it not occurred sometime between 1.6 and 2 billion years ago, our planet would be a far different place, populated entirely by prokaryotes, single-celled organisms such as bacteria and archaea. For the most part, scientists agree that eukaryotic cells arose from a symbiotic relationship between bacteria and archaea. Archaea -- which are similar to bacteria but have many molecular differences -- and bacteria represent two of life's three great domains. The third is represented by eukaryotes, organisms composed of the more complex eukaryotic cells. Eukaryotic cells are characterized by an elaborate inner architecture.