Initial regional cytoarchitectonic differences in dorsal and orbitobasal human developing frontal cortex revealed by...

Area of Science:

• Neuroscience
• Developmental Biology
• Genomics

Background:

• Human fetal cerebral cortex development involves complex, underexplored molecular processes.
• Early fetal development establishes neuronal identity, genetic programming, and histogenetic events.
• Previous work identified unique frontal lobe cytoarchitectonic features like migratory waves and a "double plate" structure.

Purpose of the Study:

• To investigate unique frontal lobe cytoarchitectonic features at the transcriptomic level while preserving spatial information.
• To examine gene expression differences in transient cortical compartments of the dorsal and ventral frontal lobe at 15 post-conceptional weeks.
• To understand early regional patterning and specification of the human prefrontal cortex.

Main Methods:

• Utilized NanoString GeoMx™ Digital Spatial Profiler (DSP) technology.
• Analyzed gene expression in transient cortical compartments of dorsal and orbitobasal frontal lobe regions.
• Focused on the critical 15 post-conceptional weeks period for subplate formation.

Main Results:

• Identified significant gene expression differences between dorsal and orbitobasal transient cortical compartments.
• Confirmed that neurons in identified cytoarchitectonic features express deep projection neuron (DPN) markers (TBR1, TLE4, SOX5).
• Highlighted distinct molecular profiles in developing dorsal and ventral frontal lobe regions.

Conclusions:

• Early fetal development demonstrates regional patterning and specification of the prospective higher-order association prefrontal cortex.
• These findings contribute to understanding the highly organized cortical architecture of the human brain.
• The study provides novel transcriptomic insights into early human frontal lobe development.