Smarcc1 drives optic stalk patterning and optic nerve head astrocyte differentiation

Area of Science:

• Developmental Biology
• Neuroscience
• Cell Biology

Background:

• The optic nerve is vital for vision, developing from the optic stalk.
• Astrocytes within the optic nerve support retinal ganglion cell axons.
• The role of SWI/SNF scaffolding subunits in optic nerve development is not fully understood.

Purpose of the Study:

• To define the progression of astrocyte formation from the optic stalk.
• To identify stage-specific functions of Smarcc1 and Smarcc2 in optic nerve development.
• To elucidate the role of Smarcc1 in optic nerve head morphogenesis and astrocyte specification.

Main Methods:

• Conditional gene deletion using Dct-Cre.
• Spatial transcriptomics.
• Functional assays.

Main Results:

• Smarcc1 loss uniquely disrupted optic nerve head morphogenesis, leading to glial lamina collapse and visual decline.
• Smarcc1 facilitates the transition of optic stalk progenitors to astrocyte progenitors by repressing pigment genes and allowing Pax2/Sox2 activity.
• Smarcc1 is essential for glial lamina assembly and astrocyte migration into the inner retina post-specification.

Conclusions:

• Smarcc1-dependent chromatin remodeling is critical for coordinating astrocyte specification with optic nerve head morphogenesis.
• Smarcc1 plays a key role in maintaining long-term retinal function through proper optic nerve development.
• These findings highlight Smarcc1 as a key regulator in the development of optic nerve astrocytes and visual pathway integrity.