Biology subjects

Trejo, B.

Publications and source records attributed to Trejo, B..

3 recordsLinked to original sources

bioRxiv2026

Dishevelled-mediated clustering stabilizes Frizzled6 and Vangl2 to establish planar cell polarity in the mammalian skin

Planar cell polarity (PCP) in epithelia is characterized by the polarized distribution of two opposing, membrane-associated PCP complexes across cell junctions. Transmembrane components of the PCP complex bridge cell junctions and organize into punctate, intercellular assemblies that exhibit a high degree of stability. Here, we define the contributions of the cytoplasmic PCP protein, Dishevelled (Dvl), in the sub-micron scale organization and stability of PCP complexes. Using endogenously-tagged fluorescent PCP reporters in the embryonic mouse epidermis, we quantify PCP protein mobility and clustering during polarization. We find that as transmembrane proteins immobilize into puncta, Dishevelled (Dvl2/3) co-accumulates with its transmembrane partner Frizzled (Fz6) in a polarized manner and stabilizes clusters of PCP complexes. We identify a previously unknown function for the oligomerizing DIX domain of Dvl3, typically associated with Wnt signaling, in Dvl3 asymmetric localization. These observations underscore a role for Dvl oligomerization in assembly and stabilization of asymmetric PCP puncta.

developmental biology↗

bioRxiv2023

A Window into Mammalian Basement Membrane Development: Insights from the mTurq2-Col4a1 Mouse Model

Basement membranes (BMs) are specialized sheets of extracellular matrix that underlie epithelial and endothelial tissues. BMs regulate traffic of cells and molecules between compartments, and participate in signaling, cell migration and organogenesis. The dynamics of mammalian BMs, however, are poorly understood, largely due to a lack of models in which core BM components are endogenously labelled. Here, we describe the mTurquoise2-Col4a1 mouse, in which we fluorescently tag collagen IV, the main component of BMs. Using an innovative Planar-Sagittal live imaging technique to visualize the BM of developing skin, we directly observe BM deformation during hair follicle budding and basal progenitor cell divisions. The BMs inherent pliability enables dividing cells to remain attached to and deform the BM, rather than lose adhesion as generally thought. Using FRAP, we show BM collagen IV is extremely stable, even during periods of rapid epidermal growth. These findings demonstrate the utility of the mTurq2-Col4a1 mouse to shed new light on mammalian BM developmental dynamics.

cell biology↗

bioRxiv2020

EEG-Beats: Automated analysis of heart rate variability (HVR) from EEG-EKG

Heart rate variability (HRV), the variation of the period between consecutive heartbeats, is an established tool for assessing physiological indicators such as stress and fatigue. In non-clinical settings, HRV is often computed from signals acquired using wearable devices that are susceptible to strong artifacts. In EEG (electroencephalography) experiments, these devices must be synchronized with the EEG and typically provide intermittent interbeat interval information based on proprietary artifact-removal algorithms. This paper describes an automated algorithm that uses the output of an EEG sensor mounted on a subjects chest to accurately detect interbeat intervals and to calculate time-varying metrics. The algorithm is designed for raw signals and is robust to artifacts, resulting in fine-grained capture of HRV that is synchronized with the EEG. An open-source MATLAB toolbox (EEG-Beats) is available to calculate interbeat intervals and many standard HRV time and frequency indicators. EEG-Beats is designed to run in a completely automated fashion on an entire study without manual intervention. The paper applies EEG-Beats to EKG signals measured with an EEG sensor in a large longitudinal study (17 subjects, 6 tasks, 854 datasets). The toolbox is available at https://github.com/VisLab/EEG-Beats.

neuroscience↗