Alternative splicing linked to mammal lifespan ^{CEFR B2}

The study in Nature Communications compared alternative RNA processing across 26 mammal species with maximum lifespans from 2.2 to 37 years (>16-fold differences). Alternative splicing is a molecular process that allows one gene to yield multiple mRNA isoforms and distinct proteins by including or skipping segments. Researchers examined six tissue types, including the brain, and found many splicing patterns linked to lifespan that are shared across species.

The brain was notable: it showed twice as many lifespan-linked splicing events as other tissues, which the authors associate with the brain's specialized functions and regulatory complexity and the presence of many splicing factors expressed only in neural tissue. Overall, changes in splicing better predict maximum lifespan than simple differences in gene expression, suggesting splicing provides a distinct, transcription-independent layer of lifespan control. The study also shows lifespan-linked splicing appears genetically programmed and tightly regulated by RNA-binding proteins rather than being a mere byproduct of aging.

Where lifespan-linked splicing overlapped with aging-linked patterns, the affected proteins often contained flexible regions that help cells cope with stress and damage. The authors propose that longer-lived species may have evolved molecular programs that optimize splicing for longevity and that such programs could allow active modification of lifespan regulation in response to environmental influences. Co-corresponding authors are Sika Zheng, professor of biomedical sciences at the University of California, Riverside School of Medicine and director of the UCR Center for RNA Biology and Medicine, and Liang Chen, professor of quantitative and computational biology at the University of Southern California. The research was funded by the National Institutes of Health.