How a Genetic Locus Protects Adult Blood-Forming Stem Cells

Hematopoietic, or blood-forming, stems cells are essential to the healthy functioning of the human body.

These cells renew themselves and differentiate into other cells, including white blood cells, red blood cells, and platelets, and constantly renew the body's blood supply.

The creation of new blood cells in the body requires a delicate metabolic balance that is not well understood. Investigator Linheng Li, PhD, and colleagues found that a particular location in DNA, called the Dlk1-Gtl2 locus, plays a critical role in protecting hematopoietic cells by restricting metabolic activity in the cells' mitochondria. This discovery suggests that Gtl2 may be useful clinically as a biomarker to determine if cells are normal or potentially cancerous. The locus's tumor suppression qualities also may lead to future treatments targeting cancer

The journal Cell Stem Cell that published the research results also featured cover art conceived and designed by Li, Postdoctoral Research Associate Pengxu Qian, PhD, and Scientific Illustrator Mark M. Miller. The cover illustration depicts a parallel between a story from Chinese mythology and the researchers' findings.

The Chinese myth holds that ten suns once flooded the earth with excessive energy, causing crops to shrivel, rivers to dry, and life to collapse. Houyi, the god of archery, shot down all but one of these suns, restoring energy balance and allowing life to flourish.

As represented in the illustration, the imprinted Dlk1-Gtl2 locus (Houyi with bow) protects and preserves hematopoietic stem cells (earth) from apoptosis by expressing multiple miRNAs (arrows) to suppress excessive reactive oxygen species production, a byproduct of energy (heat) generation from mitochondria (suns).