A 2020 view of tension-based cortical morphogenesis

Area of Science:

• Neuroscience
• Developmental Biology
• Biophysics

Background:

• Mechanical tension in neural structures is a proposed driver of nervous system morphogenesis.
• Tension-based morphogenesis (TBM) offers a simple, physics-based explanation for shaping neural tissues.
• TBM can account for the thinness, surface area expansion, and folding of the cerebral and cerebellar cortices.

Purpose of the Study:

• To review progress in understanding tension-based morphogenesis (TBM) since 1997.
• To propose revised and new models for cortical expansion and folding.
• To suggest experimental approaches for validating these models.

Main Methods:

• Review of existing literature on TBM and related morphogenetic mechanisms.
• Proposal of the differential expansion sandwich plus (DES+) model for cerebral cortex.
• Proposal of the cerebellar multilayer sandwich (CMS) model for cerebellar cortex.

Main Results:

• Studies confirm tension's significant role in diverse cellular developmental events in vitro and in vivo.
• The DES+ model integrates tangential and radial tensions to explain cerebral cortical expansion and folding.
• The CMS model addresses the unique, accordion-like folding of the cerebellar cortex.

Conclusions:

• Tension plays a critical role in nervous system development and shaping.
• The proposed DES+ and CMS models offer refined explanations for cortical morphogenesis.
• Further experiments are needed to validate the proposed models and their underlying mechanisms.