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Archive - Jan 7, 2017

Study Characterizes Key Molecular Tool in DNA Repair Enzymes

New research has revealed the function of a widely shared enzyme component, the Zf-GRF domain, as a critical molecular tool necessary for manipulating DNA during repair processes. A living organism's DNA needs constant maintenance. Every cell is in a state of fierce siege, as plentiful reactive oxygen compounds and ions constantly assault and damage the cell's organic molecules, especially its DNA. Oxidative damage to DNA is estimated to occur 10,000 times per day per cell. In order for life to survive this molecular battlefield, molecular countermeasures have evolved, among them a suite of complex molecules that detect oxidative damage to sections of DNA molecules, targeting those areas with various repair molecules that perform a series of elaborate molecular engineering operations necessary to fix the problem. The intimate mechanics of the complex molecular assemblies dedicated to the recognition, repair and signaling of DNA damage are still not fully understood. A specific protein structure known as the Zf-GRF domain is a mysterious component of APE2, a DNA-repair and DNA damage response enzyme, and is also common to a number of other DNA-maintaining molecules. A new research finding shows that Zf-GRF performs a critical DNA binding function in helping enzymes properly align to single-stranded DNA. The new study appears in a paper published online in PNAS on December 27, 2016. The article is titled "APE2 Zf-GRF Facilitates 3'-5' Resection of DNA Damage Following Oxidative Stress.” The finding is a result of two teams, one headed by Shan Yan from the Department of Biological Sciences at the University of North Carolina at Charlotte and the second headed by R.

Biomarker Signatures of Aging

Levels of specific biomarkers found in the blood can be combined to produce patterns that signify how well a person is aging and his or her risk for future aging-related diseases, according to a new study by researchers at the Boston University Schools of Public Health and Medicine and Boston Medical Center. The study, which was published online on January 6, 2016 in the journal Aging Cell, used biomarker data collected from the blood samples of almost 5,000 participants in the Long Life Family Study, funded by the National Institute on Aging (NIA) at the National Institutes of Health (NIH). The open-access article is titled “Biomarker Signatures of Aging.” The researchers found that a large number of people--about half --had an average "signature," or pattern, of 19 biomarkers. But smaller groups of people had specific patterns of those biomarkers that deviated from the norm and that were associated with increased probabilities of association with particular medical conditions, levels of physical function, and mortality risk eight years later. For example, one pattern was associated with disease-free aging, another with dementia, and another with disability-free aging in the presence of cardiovascular disease. In all, the researchers generated 26 different predictive biomarker signatures. Instances where similar biomarker data were available from the long-running Framingham Heart Study allowed for about one-third of the signatures to be replicated. "These signatures depict differences in how people age, and they show promise in predicting healthy aging, changes in cognitive and physical function, survival, and age-related diseases like heart disease, stroke, type 2 diabetes, and cancer," the authors said.