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Biology subjects

Liu, D. H.

Publications and source records attributed to Liu, D. H..

2 recordsLinked to original sources

Brain-computer interface training fosters perceptual skills to detect errors

Accurate perception of visuo-motor errors is essential for perceptual and sensorimotor learning so that corrective actions are performed timely to maintain stability and goal-directed behavior. However, a key challenge remain: conventional, behavioral perceptual training -- typically based on response accuracy feedback-- is limited in improving sensitivity to small, subtle errors. While prior approaches have focused on modulating sensory regions to enhance perceptual learning, we propose an alternative approach: targeting a cognitive neural marker, namely the error positivity (Pe), a component of the error-related potential (ErrP) that primarily originates in the anterior cingulate cortex (ACC), a key region involved in decision-making. We hypothesize that the Pe, which reflects conscious awareness of errors, serves as a modifiable neural correlate of error perception. To address the performance bottlenecks seen in conventional, behavioral perceptual training, we show that real-time feedback on ErrP presence or absence during perceptual training over five longitudinal days enhances the Pe component and improves participants ability to detect small visuo-motor errors --an outcome not achieved through conventional, behavioral perceptual training. These findings offer new neurophysiological insights into error perception and learning, and establish ErrP-based BCI interventions as a promising tool for accelerating perceptual learning, particularly in contexts where subtle error detection is critical.

bioengineering↗

Integrated structural model of the palladin-actin complex using XL-MS, docking, NMR, and SAXS

Palladin is an actin binding protein that accelerates actin polymerization and is linked to metastasis of several types of cancer. Previously, three lysine residues in an immunoglobulin-like domain of palladin have been identified as essential for actin binding. However, it is still unknown where palladin binds to F-actin. Evidence that palladin binds to the sides of actin filaments to facilitate branching is supported by our previous study showing that palladin was able to compensate for Arp2/3 in the formation of Listeria actin comet tails. Here, we used chemical crosslinking to covalently link palladin and F-actin residues based on spatial proximity. Samples were then enzymatically digested, separated by liquid chromatography, and analyzed by tandem mass spectrometry. Peptides containing the crosslinks and specific residues involved were then identified for input to HADDOCK docking server to model the most likely binding conformation. Small angle X-ray scattering was used to provide further insight into palladin flexibility and the binding interface, and NMR spectra identified potential interactions between palladins Ig domains. Our final structural model of the F-actin:palladin complex revealed how palladin interacts with and stabilizes F-actin at the interface between two actin monomers. Three actin residues that were identified in this study also appear commonly in the actin binding interface with other proteins such as myotilin, myosin, and tropomodulin. An accurate structural representation of the complex between palladin and actin extends our understanding of palladins role in promoting cancer metastasis through regulation of actin dynamics. SignificanceIn this study we have combined various advanced structural biology techniques to provide the first comprehensive model of the palladin-actin complex. Considering palladins role in cancer cell metastasis, this structure could be useful in screening and developing chemotherapeutic agents that target this interaction and prevent cancer cell metastasis.

biochemistry↗