Search bioRxiv⌕ Search

bioRxiv · 10.64898/2026.03.14.711770

Lef1 is dispensable for blood-brain barrier integrity despite its dominant role in endothelial Wnt signaling

Abstract

The blood-brain barrier (BBB) is a specialized vascular structure essential for CNS homeostasis, whose formation and maintenance are governed by the canonical Wnt signaling pathway. While the upstream ligands and receptors are well-characterized, the downstream transcriptional architecture remains poorly understood. Here, we investigate the functional requirement for Lef1, the most abundant Tcf/Lef transcription factor and a hallmark readout of Wnt activity in brain endothelial cells (BECs). Utilizing a conditional, endothelial-specific deletion strategy in mice, we demonstrate that loss of Lef1 during either embryonic development or adult homeostasis significantly dampens Wnt transcriptional output. Surprisingly, high-resolution molecular and functional analysis reveals that this reduction results in only minor dysregulation of the BBB-specific gene program and is insufficient to trigger barrier breakdown. Our results establish that Lef1 is not an obligatory effector of the Wnt-dependent BBB maintenance program. These findings suggest a resilient transcriptional framework where redundant Tcf/Lef family members or alternative regulatory circuits preserve CNS microvasculature function, providing new insights into the genetic robustness of the blood-brain barrier. Research HighlightsO_LILef1 is the predominant Tcf/Lef transcription factor in the brain endothelium and a hallmark of vascular Wnt signaling. C_LIO_LIEndothelial-specific Lef1 deletion significantly attenuates Wnt transcriptional output during both CNS vascular development and adult homeostasis. C_LIO_LILoss of Lef1 causes only minor perturbations in the BBB-specific gene program, rather than a global loss of endothelial identity. C_LIO_LIStructural and functional BBB integrity is preserved in the absence of Lef1, revealing a high degree of vascular resilience. C_LIO_LIThe findings demonstrate that Lef1 is not an obligatory effector for the maintenance of the specialized CNS microvasculature. C_LI

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Ben Zvi, A., Yeretz Peretz, Y., Anzi, S., Bell, B.. 2026-03-17. Lef1 is dispensable for blood-brain barrier integrity despite its dominant role in endothelial Wnt signaling. https://doi.org/10.64898/2026.03.14.711770

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related preprints

Attention Across Scales: From Individual Variation to Social Hierarchies and Brain Networks in Semi-Free-Ranging Macaques

Attention is a fundamental brain function supporting perception, decision-making, and social behavior, and its dysfunction profoundly impairs daily life. It is both dynamic and stable, varying across observations and individuals, changing across the lifespan, and being shaped by social and environmental experience. Yet capturing this complexity remains a central challenge in neuroscience. Here, we integrated longitudinal behavioral assessments of semi-free-ranging macaques living in naturalistic social groups with resting-state fMRI. We quantified performance across days, ages, and social hierarchies and related it to intrinsic brain organization. Distinct attentional phenotypes emerged, including individuals with reduced attentional control. Performance followed an inverted-U lifespan trajectory, improving from childhood to adulthood before declining. Social status modulated attentional performance. Critically, nonlinear lifespan trajectories and associations with individual attentional differences were most clearly expressed in frontoparietal connectivity. Together, these findings reveal how sustained attention is organized across scales, providing a biological framework for its individual diversity, social modulation, and neural basis.

neuroscience↗

Decoding natural scenes from patterned optogenetic responses in mouse visual cortex

A central challenge in developing visual cortical prostheses is to determine how visual stimuli should be transformed into effective patterns of cortical stimulation. Although advances in stimulation technologies, including optogenetics, provide increasingly precise control over cortical activity, it remains unclear whether artificially evoked activity can reproduce the information content of naturally evoked visual representations. Here we establish a quantitative framework for evaluating visual encoding strategies by decoding cortical responses evoked by natural vision and patterned optogenetic stimulation. We developed a novel dual-modal paradigm in awake mice to bridge the gap between endogenous photostimulation and artificial network driving. By co-expressing the high-performance calcium indicator GCaMP6s and the red-shifted, ultra-sensitive opsin rsChRmine-oScarlet in the primary visual cortex (V1), we successfully translated dynamic natural movie frames into patterned, spatiotemporal optogenetic stimulation. Quantitative comparisons of macro-scale dynamics demonstrated that this patterned optogenetic injection evokes cortical states highly comparable and representationally aligned with those driven by actual visual photostimulation. To systematically evaluate the fidelity of these responses, we developed STAR, a deep learning model featuring spatial and temporal attention mechanisms, and successfully reconstructed the frames of natural movies from V1 signals under both experimental modalities. Collectively, our results demonstrate that complex sensory information can be both naturally encoded and synthetically injected into V1 circuits with high decoding fidelity. This work provides an empirical and computational proof-of-concept for intelligent, closed-loop biomimetic encoders, establishing a robust framework for next-generation cortical visual neuroprostheses and bidirectional brain-machine interfaces.

neuroscience↗

Why Is Spontaneous Blink Timing Informative? An Adaptive Scheduling Perspective

Spontaneous eye blinks have long been linked to cognitive processing, yet how task demands shape blink timing and its relationship to behavioral performance remains unclear. We examined spontaneous blink behavior in 576 adults performing two variants of the Continuous Performance Task (CPT). Blink occurrence and timing were most strongly modulated by the experimental condition in the more demanding CPT-AX task, whereas their association with response time was stronger in the CPT-X task, where more consistent blink timing predicted faster responses. This dissociation suggests that task structure changes not only blink behavior but also the behavioral relevance of blink timing. These findings are consistent with an adaptive scheduling account of spontaneous blinking and provide a conceptual framework for understanding when and why blink timing contains chronometric information about ongoing cognition.

neuroscience↗