Researchers Uncover Key Role of Nonsense-Mediated Decay in Brain Development

Study shows UPF2 protein is essential for proper neuronal migration and cortical lamination

Published on Feb. 26, 2026

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Researchers at the University of California, Riverside have discovered that nonsense-mediated mRNA decay (NMD), a fundamental regulated RNA decay pathway, plays a central role in the proper development of the cerebral cortex. The study, published in Cell Reports, shows that the UPF2 protein, a core component of the NMD machinery, is essential for guiding newly generated neurons to their designated locations during brain development. Disruptions in this process can lead to profound alterations in cortical circuitry, contributing to a range of neurodevelopmental disorders.

Why it matters

The cerebral cortex, the brain's outermost region responsible for higher cognitive functions, depends on a highly ordered, layered structure. Defects in neuronal migration or cortical lamination can impair synaptic connectivity and information processing, leading to neurodevelopmental disorders like epilepsy, intellectual disability, autism spectrum disorders, and schizophrenia. Understanding the molecular mechanisms that govern this process is crucial for developing potential treatments and interventions.

The details

The researchers found that selectively removing the UPF2 protein from radial glial cells and their neuronal progenies resulted in defects in neuronal migration, with neurons moving more slowly and some failing to reach their designated cortical layers. This disrupted the normal laminar organization of the cortex. They also discovered that brains lacking UPF2 were significantly smaller, but this brain size reduction could be rescued by turning off the p53 protein, which normally slows down cell proliferation. However, the disorganized cortical layers remained, indicating that UPF2 has a separate role in helping neurons move to the right place during development.

  • The study was published in Cell Reports in February 2026.

The players

Sika Zheng

A professor of biomedical sciences at the University of California, Riverside who led the study.

University of California, Riverside

A doctoral research university where the study was conducted.

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What they’re saying

“By selectively removing UPF2 from radial glial cells and their neuronal progenies, we observed defects in neuronal migration. Neurons moved more slowly and some failed to reach their designated cortical layers. As a result, the normal laminar organization of the cortex was lost.”

— Sika Zheng, Professor of biomedical sciences (Cell Reports)

“The layers of the brain, however, were still disorganized. This told us UPF2 isn't just needed to develop a normal brain size; it also has a separate job helping neurons move to the right place during development.”

— Sika Zheng, Professor of biomedical sciences (Cell Reports)

What’s next

The researchers plan to further investigate the specific molecular mechanisms by which UPF2 and the NMD pathway regulate neuronal migration and cortical lamination, with the goal of developing potential interventions for neurodevelopmental disorders.

The takeaway

This study provides crucial insights into how disruptions in the nonsense-mediated mRNA decay pathway, particularly the UPF2 protein, can lead to abnormal brain development and structure, contributing to a range of neurological and psychiatric conditions. Understanding these fundamental mechanisms is a critical step towards developing new therapeutic approaches.