The action of a key gene is required to maintain a lifelong supply of stem cells that make bone healing possible, a new study finds.

These immature cells are known to get the signal to either continually divide to make more copies of themselves (self-renewal) as a ready pool of replacements, or to mature into cells with a specific function like bone-building. Once they mature, they generally cannot reverse the process, so the supply of stem cells is limited. Such pools become even more depleted as people age.

Led by NYU Langone Health researchers, the new work identified the gene HOXA10 as a lifelong protector of the stem cell supplies, keeping them from maturing into bone-building cells called osteoblasts until needed for healing.