Elevated nuclear TDP-43 induces constitutive exon skipping

Area of Science:

• Molecular Biology
• Neuroscience
• Genetics

Background:

• TDP-43 proteinopathies are linked to cytoplasmic inclusions and nuclear loss of TDP-43.
• Gain- and loss-of-function mechanisms are implicated in neurodegenerative diseases involving TDP-43.

Approach:

• Investigated TDP-43 gain-of-function using overexpression models.
• Analyzed species-specific effects of excessive nuclear TDP-43 on RNA splicing.
• Examined correlation between aberrant exon skipping and human neurodegenerative disease.

Key Points:

• TDP-43 overexpression induces constitutive exon skipping, with significant species-specific differences.
• Aberrant exon skipping in human brains was not correlated with disease state.
• Loss of TDP-43, not overexpression, correlated with cryptic exon incorporation.

Conclusions:

• Caution is required when interpreting TDP-43 overexpression data in disease models.
• Controlling for TDP-43-induced exon skipping is crucial for accurate modeling of TDP-43 proteinopathies.
• Understanding TDP-43's subcellular toxicity is key for developing neurodegenerative disease therapies.