Stem Cells

Whitehead Institute researchers have created a complete catalog of genes active in the planarian eye. Several identified genes are known to have versions that play a role in the vertebrate eye, including genes involved in eye development and others associated with age-related macular degeneration and Usher syndrome, a disorder that causes progressive retinal degradation.

Despite their unassuming appearance, the planarian flatworms in Whitehead Institute Member Peter Reddien's lab are revealing powerful new insights into the biology of stem cells—insights that may eventually help such cells deliver on a promising role in regenerative medicine.

Whitehead Institute researchers have determined the critical role one enzyme, lysine-specific demethylase 1 (LSD1), plays as mouse embryonic stem cells (ESCs) differentiate.

By irradiating typical polystyrene lab plates with ultraviolet (UV) waves, Whitehead Institute and MIT scientists have created a surface capable of tripling the number of human embryonic stem (ES) and induced pluripotent stem (iPS) cells that can be grown in culture by current methods.

New findings by scientists at the Broad Institute of MIT and Harvard and Whitehead Institute point to a decentralized society in tumors, with cancer cells able to interconvert between different types. These results have potential implications for the treatment of tumors, in particular, that attacking cancer stem cells alone may not be enough to fight cancer.

Whitehead Institute researchers have identified signals impinging on breast epithelial cells that can induce those cells to acquire and stably display migratory and self-renewing characteristics.

Whitehead Institute researchers have determined that the planarian flatworm regenerates missing tissues by using pluripotent adult stem cells. Until now, scientists could not determine whether the dividing cells in planarians, called neoblasts, are a mixture of specialized stem cells that each regenerates specific tissues, or if individual neoblasts are pluripotent and able to regenerate all tissues.

A little-studied gene known as notum plays a key role in the planarian’s regeneration decision-making process, according to Whitehead Institute scientists. At head-facing (anterior) wounds, the gene notum acts as a dimmer switch to dampen the Wnt pathway—an ancient signaling circuit that operates in all animals—and promote head regeneration.