New insights into cortical interneurons development and classification: contribution of developmental studies

Area of Science:

• Neuroscience
• Developmental Biology
• Cell Biology

Background:

• Cerebral cortex development involves coordinated GABAergic interneuron and glutamatergeric neuron formation.
• GABAergic interneurons exhibit significant heterogeneity in morphology, markers, connectivity, and physiology.
• Interneurons originate from diverse telencephalic structures, including ganglionic eminences and the cortex.

Purpose of the Study:

• To review the origin, specification, and differentiation of GABAergic interneurons.
• To explore how developmental studies clarify the classification of mature interneurons.
• To discuss the influence of target tissues on interneuron physiological properties.

Main Methods:

• Review of recent developmental studies on interneuron origins.
• Analysis of evidence regarding interneuron specification timing and location.
• Discussion of factors influencing interneuron differentiation and maturation.

Main Results:

• Most interneurons are specified after their final division within their region of origin, prior to migration.
• Developmental origins and specification processes contribute to interneuron heterogeneity.
• Target tissues play a role in determining the final physiological characteristics of interneurons.

Conclusions:

• Understanding interneuron development is crucial for classifying mature cortical neurons.
• Specification in the region of origin before migration is a key developmental event for most interneurons.
• Interneuron heterogeneity arises from complex developmental processes influenced by intrinsic and extrinsic factors.