German scientists have shed light on the molecular mechanism which leads to a rare form of myopia.
Researchers at the Max Delbrück Center for Molecular Medicine in the Helmholtz Association (MDC) in Germany, uncovered that the LRP2 receptor regulates the growth and development of stem cells in the margins of the retina.
The receptor interacts with the sonic hedgehog (SHH) signalling molecule. SHH is a protein which plays a critical role in the development of the eyes in embryos, signalling stem cells in the retina to grow, divide and mature into different types of retinal cells.
LRP2 receptors degrade and clear the SHH signal molecules, keeping the pool of stem cells at the retinal margins in a ‘resting’ state. But in studies with mice lacking LRP2, the team found that SHH caused the stem cells to proliferate, ultimately extending the length of the eye.
The team explained that the expanding retinal margin may be the underlying cause of enlarged eyes and severe myopia in patients who are LRP2-defficient.
The findings are published in the journal Developmental Cell.
Image credit: Peter Znamensky