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Castano Diez, D.

Publications and source records attributed to Castano Diez, D..

2 recordsLinked to original sources

Ice Finder: Few-Shot Learning for Non-Vitrified Ice Segmentation

This study introduces Ice Finder, a novel tool for quantifying crystalline ice in tomography, filling a crucial gap in existing methodologies. We establish the first application of the meta-learning paradigm to tomography, demonstrating that various tomographic tasks across datasets can be unified under a single meta-learning framework. Our approach utilizes few-shot learning to enhance domain generalization and adaptability to domain shifts, facilitating rapid adaptation to new datasets with minimal examples. Ice Finders performance is evaluated on a comprehensive set of in situ datasets from EMPIAR, proving its ease of use and fast processing capabilities, with inference times in the milliseconds. This tool not only accelerates workflows but also enhances the precision of structural studies in structural biology.

bioinformatics↗

Nanoscale architecture of a VAP-A-OSBP tethering complex at membrane contact site

Membrane contact sites (MCS) are subcellular regions where two organelles appose their membranes to exchange small molecules, including lipids. Structural information on how proteins form MCS is scarce. We designed an in vitro MCS with two membranes and a pair of tethering proteins suitable for cryo-tomography analysis. It includes VAP-A, an ER transmembrane protein interacting with a myriad of cytosolic proteins, and oxysterol-binding protein (OSBP), a lipid transfer protein that transports cholesterol from the ER to the trans Golgi network. We show that VAP-A is a highly flexible protein, allowing formation of MCS of variable intermembrane distance. The tethering part of OSBP contains a central, dimeric, and helical T-shape region. We propose that the molecular flexibility of VAP-A enables the recruitment of partners of different sizes within MCS of adjustable thickness, whereas the T geometry of the OSBP dimer facilitates the movement of the two lipid-transfer domains between membranes.

cell biology↗