Alternative Splicing Emerges as Key Regulator of Learning in C. elegans, Operating Through Mitochondrial Signaling
Researchers profiling gene expression in C. elegans neurons during a learning paradigm found that alternative splicing (AS) systematically remodels neuronal gene expression in response to experience. Unlike changes in transcript abundance, AS operates on a functionally distinct set of genes, establishing it as a separate regulatory layer. The findings suggest AS plays a broader, previously underappreciated role in shaping the physiological states that enable learning.
A new preprint on bioRxiv reports that alternative splicing — a process by which a single gene can produce multiple protein variants — acts as a genome-wide regulatory mechanism during learning in the roundworm C. elegans. By profiling the pan-neuronal translatome during a defined learning paradigm, the researchers found that AS-regulated genes are functionally distinct from those undergoing changes in overall transcript abundance, indicating AS constitutes an independent layer of gene regulation in response to experience. A key example identified is twnk-1, a neuronally enriched worm ortholog of a mitochondrial DNA helicase, which shows significant learning-associated AS changes. Both isoforms of twnk-1 act within a pair of sensory neurons but perform distinct functions, and AS of this gene modulates a cell-nonautonomous signal from neuronal mitochondria to peripheral tissues. The authors argue these results establish AS as a systematic regulator of learning and provide a mechanistic account of how isoform switching shapes whole-organism physiological states to facilitate learning.
What's missing
As a preprint, this work has not yet undergone peer review. The study is conducted entirely in C. elegans, and the extent to which these AS mechanisms generalize to vertebrate or mammalian learning is not addressed. The specific peripheral tissue signals downstream of twnk-1 AS and the precise physiological states they regulate remain to be fully characterized.
What different sources said
- bioRxivCenter
Systematic Profiling and Functional Characterization of Alternative Splicing in C. elegans Olfactory Learning
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