What is the role of Reelin in cortical development?

What is the role of Reelin in cortical development?

• A. Reelin promotes early neurogenesis
• B. Reelin regulates stop signal for migrating neurons and helps establish inside-out cortical layering
• C. Reelin triggers ventriculomegaly
• D. Reelin is involved in myelination

Answer: (B)

Reelin's role in cortical development is to provide a stop signal for migrating neurons and help establish the normal inside-out layering of the cortex. It is secreted by specialized cells in the marginal zone and binds to receptors on migrating neurons, triggering signaling that reorganizes the cytoskeleton and causes neurons to halt at their proper positions. This signaling ensures that later-born neurons migrate past earlier-born ones and settle in more superficial layers, creating the characteristic laminar order. When Reelin signaling is disrupted, neurons can fail to stop correctly, leading to disorganized or inverted cortical lamination. Reelin is not primarily driving neurogenesis, nor is it directly responsible for ventriculomegaly or myelination, so those options don’t describe its main developmental role.

Reelin's role in cortical development is to provide a stop signal for migrating neurons and help establish the normal inside-out layering of the cortex. It is secreted by specialized cells in the marginal zone and binds to receptors on migrating neurons, triggering signaling that reorganizes the cytoskeleton and causes neurons to halt at their proper positions. This signaling ensures that later-born neurons migrate past earlier-born ones and settle in more superficial layers, creating the characteristic laminar order. When Reelin signaling is disrupted, neurons can fail to stop correctly, leading to disorganized or inverted cortical lamination. Reelin is not primarily driving neurogenesis, nor is it directly responsible for ventriculomegaly or myelination, so those options don’t describe its main developmental role.