Using a nuclear protein
expressed in follicle stem cells (FSCs), the researchers found that castor, which plays an important role in specifying which types of brain cells are produced
during embryonic development, also helps maintain FSCs throughout the life of the animal.
Seeking fresh sources, they looked for cells that
express the gene neurogenin 3, a potential sign of cell differentiation because it is the first gene to only switch on in pancreatic islets
during embryonic development.
Eight HARs showed differences in their enhancer activity when the human mutations were present.4 These differences modify how genes were
expressed in the developing limb (HAR2, 2xHAR114), eye (HAR25), and central nervous system (2xHAR142, 2xHAR238, 2xHAR164, 2xHAR170, ANC516 / HARE5).4, 10 Because relatively few time points have been examined, it is likely that an even higher percentage of the tested HARs are active enhancers at some point
during embryonic development or in adult tissues, possibly with human - chimp differences.