Death receptor 5 and neuroproliferation.

Area of Science:

• Neuroscience
• Cell Biology
• Developmental Biology

Background:

• Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) binds DR4 and DR5, inducing apoptosis.
• DR5 is found in the developing central nervous system (CNS), potentially regulating neurogenesis.
• The role of DR5 in neurogenesis requires further investigation.

Purpose of the Study:

• To map the distribution of DR5 expression in the developing mouse brain.
• To determine if DR5 is expressed by neuroprogenitor cells and newborn neurons.
• To elucidate the potential role of DR5 in neurogenesis.

Main Methods:

• Immunohistochemistry for DR5 in mouse brain sections from embryonic day 16 to postnatal day 180.
• 5-bromo-deoxyuridine (BrdU) labeling to identify proliferative cells.
• Co-localization studies with markers for progenitor cells (Doublecortin) and glial cells (GFAP).

Main Results:

• DR5 expression was observed in the embryonic hippocampus, dentate gyrus, subventricular zone, and RMS.
• Postnatally, DR5-positive cells were concentrated in the subgranular layer (SGL) and RMS.
• Proliferative cells in the SGL selectively expressed DR5, with lower levels in newborn neurons.
• DR5 was also found in stem cells of the intestine and cerebellum, and in proliferative Bergmann cells.

Conclusions:

• DR5 is selectively expressed by neuroprogenitor cells and newborn neurons in the developing mouse brain.
• DR5 expression patterns suggest a role in neuroproliferation and differentiation.
• DR5 may be a key regulator of neurogenesis.