The Sebastiano Lab
Prevailing views about aging are shaped by the dogma that development and aging are irreversible. This dogma is exemplified by the famous illustration of the Epigenetic Landscape by C.H. Waddington. The Epigenetic Landscape depicts how we grow after fertilization or as we age, the epigenetics of our cells change, and these changes are “cumulative” and additive and cannot be taken back.
While this is true for the most part, recent stem cell and developmental biology research teaches us also that such irreversible mechanisms can be “undone”. How is this possible?
During preimplantation embryonic development and during primordial germ cell specification there is a natural and massive phenomenomn of epigenetic reprogramming that erases the cell identity of the cells and establishes a brand new program. In 2006-2007 Dr. Shinya Yamanaka made a pioneering discovery showing that a similar process of reprogramming can be achievedin differentiated mouse or human cells by overexpressing a handful of transcription factors. Yamanaka's reprogramming process restored the differentiated cells to a pluripotent state, making them once again capable of recapitulating the scope of normal development.
Subsequent research over the past decade has led us to the realization that the Epigenetic Landscape is highly malleable and can be remodeled or “reprogrammed” to various distinct fates. Research in the Sebastiano lab applies this new insight to the challenge of understanding and ameliorating aging.
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Old human cells rejuvenated
Old human cells can become more youthful by coaxing them to briefly express proteins used to make induced pluripotent cells, Stanford researchers and their colleagues have found. The finding may have implications for aging research.
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Bee-made protein keeps stem cells primed
An active protein component of royal jelly helps honeybees create new queens. Stanford researchers have identified a similar protein in mammals, which keeps cultured embryonic stem cells pluripotent.
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New protein essential for making stem cells
The discovery by Stanford scientists drills a peephole into the black box of cellular reprogramming and may lead to new ways to generate induced pluripotent stem cells in the laboratory.
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Viral genetic material aids human development
Genetic residue from ancient viral infections has been repurposed to play a vital role in acquiring pluripotency, the developmental state that allows a fertilized human egg to become all the cells in the body.
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Letter describes impact on critical research
In September, the National Institutes of Health halted research funding for chimeric human/nonhuman embryos until new funding guidelines are established. Stanford researchers describe the detrimental impact of a ban.
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Correcting a devastating collagen defect
In laboratory experiments, researchers were able to correct a collagen defect — the source of a blistering skin disease — in stem cells made from patients.
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Pilot stem cell class gives undergrads hands-on experience
The first year of college is always a whirlwind of experiences.
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Scientists turn human skin cells directly into neurons, skipping iPS stage
Human skin cells can be converted directly into functional neurons in a period of four to five weeks with the addition of just four proteins, according to a study by researchers at the Stanford University School of Medicine.