News & Comment

The cerebellum is more than just motor control: over the past 30 years, the notion that the “little brain” participates in cognitive functions and emotional response has grown to encompass social-related behaviors. Chao et al. bring to light the role of the cerebellar vermis in orchestrating a specific component of social memory in mice.

Retinal degenerative diseases are often multifaceted and difficult to treat, instead requiring more targeted or personalized therapeutic solutions. Recent work by Liu et al. reveals one such pipeline to engineer extracellular vesicles that can selectively reduce the spread of retinal inflammation and prevent the progression of vision loss in rodent models of retinal degeneration. This approach is representative of a new wave of precision medicines with the potential to treat these otherwise incurable diseases.

Although liquid-liquid phase separation (LLPS) has been extensively studied in various cellular and organismal contexts, the link between functional influence of a genetic mutation and LLPS with respect to human diseases is poorly understood. A recent article by Mensah et al. looks at a rare genetic disease to identify a frameshift mutation, which triggered aberrant phase separation and nucleolar dysregulation, linking genetic variants to a dysregulation of biomolecular condensates.

Behavioral results suggest that learning by trial-and-error (i.e., reinforcement learning) relies on a teaching signal, the prediction error, which quantifies the difference between the obtained and the expected reward. Evidence suggests that distinct cortico-striatal circuits are recruited to encode better-than-expected (positive prediction error) and worst-than-expected (negative prediction error) outcomes. A recent study by Villano et al.¹ provides evidence for differential networks that underlie learning from positive and negative prediction errors in humans using real-life behavioral data. More specifically, they found that university students are more likely to update beliefs concerning grade expectations following positive rather than negative prediction errors.

Cilia assembly and function require intraflagellar transport (IFT), a mechanism that uses “trains” to transport cargoes into and out of cilia. While much has been learned about IFT in the past decades, IFT train assembly, loading of cargo and transport regulation have remained poorly understood. In a recent study, Hesketh, Mukhopadhyay and colleagues obtained the complete structure of the IFT-A complex, a key element of IFT trains. By modelling IFT-A into anterograde trains and performing structure-guided mutagenesis, the authors uncover how the IFT-A complex polymerizes and forms carriages to accomplish its distinctive functions.

The BIL1/BZR1 transcription factor is known to regulate transcriptional responses to the brassinosteroid class of phytohormones by directly recognizing short cis regulatory elements in promoters. A new study by Shohei Nosaki, Nobutaka Mitsuda, and colleagues published in Nature Plants indicates that binding of this transcription factor is additionally affected by nucleobases that influence DNA shape but are not directly contacted by BIL1/BZR1.