Dr Sean Coakley

Queensland Brain Institute

Title: Spectrin forms a periodic cytoskeleton within the epidermis to preserve axonal integrity

Neurons are highly polarized cells with complex cellular architectures consisting of slender axons and dendrites that are often highly branched and traverse large distances. The maintenance of these fragile connections is critical for nervous system function and understanding the cellular mechanisms of such neuroprotective pathways is a central question in neurobiology. The cytoskeletal spectrin network is present in all cells and regulates cellular architecture and mechanical stability. Importantly, spectrins are required for axonal integrity and human mutations in ß-Spectrin are associated with several disorders, including spinocerebellar ataxia, a neurodegenerative disorder characterised by uncoordinated gait, limb and eye movement defects, slurred speech and swallowing difficulties. Recently, we discovered that ß-Spectrin functions within the skin to maintain the structural integrity of sensory axons in C. elegans, although the mechanisms of this protection and its molecular organization are unknown. Here, using 3D-structured illumination microscopy, we show that within the epidermis spectrins form a crescent-shaped scaffold with a periodicity of ~ 200 nm that embraces adjacent axons of the C. elegans nervous system. This epidermal spectrin scaffold is induced by developing axons and reformed during axonal regeneration, creating a “molecular imprint” of adjacent axons. Disruption of this epidermal scaffold causes widespread axonal damage in sensory and motor neurons. These findings reveal the existence of a distinct and periodic spectrin network within the epidermis that is molded by the developing nervous system and necessary to protect it from mechanical damage.

About Neuroscience Seminars

Neuroscience seminars at the QBI play a major role in the advancement of neuroscience in the Asia-Pacific region. The primary goal of these seminars is to promote excellence in neuroscience through the exchange of ideas, establishing new collaborations and augmenting partnerships already in place.

Seminars in the QBI Auditorium are held on Wednesdays at 12-1pm, which are sometimes simulcast on Zoom (with approval from the speaker). We also occassionally hold seminars from international speakers via Zoom. The days and times of these seminars will vary depending on the time zone of the speaker. Please see each seminar listed below for details. 


Neuroscience Seminars archive 2005-2018