Afadin controls cell polarization and mitotic spindle orientation in developing cortical radial glia

Area of Science:

• Neuroscience
• Developmental Biology
• Cell Biology

Background:

• Cell polarity and tissue architecture are vital for regulating cell proliferation and differentiation in developing tissues.
• Adherens junctions connect polarized radial glial cells within the neurogenic niche of the developing cerebral cortex.
• The precise role of adherens junctions in regulating radial glial cell polarity and differentiation during mammalian cortical development remains unclear.

Purpose of the Study:

• To investigate the function of Afadin, a protein essential for epithelial tissue formation and maintenance, in mammalian cortical development.
• To determine how Afadin influences radial glial cell polarity and adherens junction integrity.
• To elucidate the impact of Afadin on progenitor cell behavior, including mitotic orientation and neurogenic niche exit.

Main Methods:

• Conditional deletion of the Afadin gene in developing mammalian cortex.
• Microscopic analysis of radial glial cell polarity and adherens junction structure.
• Assessment of progenitor cell division orientation and neuroepithelial exit.

Main Results:

• Conditional deletion of Afadin resulted in disrupted radial glial cell polarity and loss of adherens junctions.
• An increase in obliquely-oriented progenitor cell divisions was observed.
• Increased exit of cells from the ventricular zone neuroepithelium and elevated production of intermediate progenitors were noted.

Conclusions:

• Afadin is essential for maintaining apical-basal polarity and adherens junction integrity in radial glial cells.
• Epithelial architecture, regulated by Afadin, plays a critical role in preserving radial glial identity.
• Afadin influences mitotic orientation and prevents premature neurogenic niche exit, thereby regulating progenitor cell behavior.