Cerebellar granular neuron precursors (CGNPs) are cells integral to the development of the cerebellum, the part of the brain that coordinates and regulates muscular activity.

The “Sonic hedgehog” (Shh) protein secreted by Purkinje cells stimulates proliferation in adjacent CGNPs, which ultimately migrate radially along Bergmann glia. The function of these glial cells during CGNP proliferation is not well defined.

Since CGNPs are the presumed cell-of-origin for a subset of the malignant pediatric brain tumor medulloblastoma, understanding the cellular and molecular factors that govern their proliferation is critical.

In a study published in the journal Developmental Biology, Chin Chiang, PhD, and colleagues demonstrate that depletion of Shh signaling in Bergmann glia in mice leads to underdevelopment of the cerebellum, a significant reduction in CGNP proliferation and disorganization of the Bergmann glia network itself.

These findings demonstrate a previously unappreciated role of Bergmann glial Shh signaling activity in CGNP proliferation and its contribution to the proper maintenance of cerebellar architecture.