Retrotransposons as Agents of somatic diversity, disease and aging

Seminar Overview: Transposable elements make up nearly 50% of the sequence in each of our cells. Retrotransposons (RTEs), in particular, are capable of being expressed, copy themselves and mobilizing to new places in the genome of our somatic cells. This talk will focus on the retrotransposon theory of aging which states that:
•    RTEs are epigenetically silenced in somatic cells; incorporated into constitutive heterochromatin and gradually activated during aging;

•    RTE activation occurs due to the failure of the normal defense mechanisms with age;

•    Surveillance mechanisms become weakened by accumulation of macromolecular damage and loss of homeostatic capacity; in part due to genotoxic stresses;

•    RTEs are expressed due to a failure of repressive constitutive heterochromatin to remain condensed;

•    Increased RTE activity is deleterious to cell function and may be one of the molecular causes of aging;

•    We hypothesize that intervening with or reversing the activation of RTEs during aging will have a beneficial effect on tissue function and healthspan.

Bio: Dr. Helfand received his BS at Stanford University with Distinction, his MD from Albert Einstein College of Medicine, performed his Medical Internship at Montefiore Medical Center, his Neurology Residency at the Massachusetts General Hospital and is Board Certified in Neurology and Psychiatry. He did his Postdoctoral training at Stanford with Corey S. Goodman and David S. Hogness and with John Carlson at Yale. He became a faculty member at UConn Health Center and since 2005 has been a Professor in the Department of Molecular Biology, Cell Biology and Biochemistry at Brown University.  

Dr. Helfand's laboratory focuses on understanding the molecular genetic mechanisms underlying aging and longevity using the model system, Drosophila melanogaster.  Dr. Helfand is a recipient of a MERIT award from the NIA, an Ellison Medical Foundation Senior Scholar and two Glenn Awards for research in Biological Mechanisms of Aging.  He is a former Editor-in-Chief of Aging Cell and a founding Editor of Aging. His work on the molecular genetics of aging has been published in Science, Nature, PNAS, Cell Metabolism, Current Biology, Nature Communications, Genetics, Aging Cell and Aging.