Biology subjects

Angulo-Capel, J.

Publications and source records attributed to Angulo-Capel, J..

5 recordsLinked to original sources

bioRxiv2026

Uncovering the function of Wisp1 in whole-body glucose homeostasis: insights from Wisp1 knockout mice

WNT1-inducible signaling pathway protein 1 (Wisp1/CCN4) is a matricellular protein implicated in inflammation and metabolic dysfunction in obesity, yet its role in whole-body glucose metabolism remains unclear. In this study, Wisp1 knockout (KO) mice were analysed under physiological and high-fat (HF) diet conditions to define its impact on metabolic regulation. Neither physiological nor HF diet conditions revealed an effect of Wisp1 deficiency on whole-body glucose tolerance. However, male KO mice on a HF diet exhibited enhanced insulin sensitivity, lower insulin levels, and a marked reduction in adipose tissue inflammation, as evidenced by diminished macrophage infiltration and decreased pro-inflammatory cytokine expression in visceral fat. Additionally, beta cell mass expansion was attenuated in KO mice under HF diet, aligning with lower macrophage infiltration in islets. These findings suggest that improved insulin sensitivity in KO mice occurs independently of changes in glucose tolerance, likely due to mitigated adipose tissue inflammation. Thus, Wisp1 primarily modulates local adipose inflammatory responses, indirectly affecting islet adaptation to metabolic stress, rather than serving as a direct regulator of systemic glucose homeostasis.

physiology↗

bioRxiv2026

A PKD-caveolin axis drives secretory carrier biogenesis at the TGN

Constitutive secretion from the trans-Golgi network (TGN) to the cell surface proceeds via carriers thought to form without a canonical cytoplasmic coat, yet how these carriers are generated remains poorly understood. Here, we identify a distinct population of TGN-to-cell surface carriers transporting influenza hemagglutinin (HA) and uncover a coat-like mechanism underlying their formation. HA carrier biogenesis requires non-vesicular lipid transfer at endoplasmic reticulum (ER)-Golgi membrane contact sites (MCSs) and protein kinase D (PKD) activity. We show that caveolin promotes membrane budding by assembling into cholesterol- and PKD-associated oligomers that act as a membrane-embedded, coat-like scaffold at lipid nanodomain-enriched TGN subdomains. These findings establish caveolin as a structural and regulatory component of TGN export and support a model in which a PKD-caveolin axis couples ER-Golgi lipid transfer to cargo sorting, membrane remodeling and fission during secretory carrier biogenesis.

cell biology↗

bioRxiv2025

Mechanical forces stimulate Golgi export

Cells face diverse mechanical stimuli that vary with cell type, state, and pathological conditions. Mechanobiology investigates how cells sense and respond to these forces. While most work has focused on the cell surface and nucleus as primary mechanosensors, how intracellular organelles adapt to extracellular mechanical forces remains largely unknown. Here, we show that extracellular mechanical signals influence the secretory function of the Golgi apparatus. By subjecting adherent cells to mechanical challenges -cell spreading on different ligands, altered substrate stiffness, or equibiaxial strain-, we reveal that extracellular forces modulate Golgi-to-cell surface carrier biogenesis, thereby regulating exocytosis. Together with changes in Golgi membrane tension, we identify molecular determinants of the mechanotransduction pathway, including microtubule acetylation, diacylglycerol production, and protein kinase D activity. In turn, inhibition of Golgi export suppresses this mechanoresponse and causes impaired cell spreading. These findings uncover a bidirectional mechanotransduction axis in which extracellular mechanics tune Golgi secretory output, providing a framework for investigating organelle-based mechanoadaptation in physiology and disease.

cell biology↗

bioRxiv2023

Nanoscale imaging reveals the mechanisms of ER-to-Golgi transport via a dynamic tubular-vesicular network

The endoplasmic reticulum (ER) and the Golgi apparatus are the first sorting stations along the secretory pathway of mammalian cells and have a crucial role in protein quality control and cellular homeostasis. While machinery components mediating ER-to-Golgi transport have been mapped, it is unclear how exchange between the two closely juxtaposed organelles is coordinated in living cells. Here, using gene editing to tag machinery components, live-cell confocal and stimulated emission depletion (STED) super-resolution microscopy, we show that ER-to-Golgi transport occurs via a dynamic network of tubules positive for the small GTPase ARF4. swCOPI machinery is tightly associated to this network and moves with tubular-vesicular structures. Strikingly, the ARF4 network appears to be continuous with the ER and ARF4 tubules remodel around static ER exit sites (ERES) defined by COPII machinery. We were further able to dissect the steps of ER-to-Golgi transport with functional trafficking assays. A wave of cargo released from the ER percolates through peripheral and Golgi-tethered ARF4 structures before filling the cis-Golgi. Perturbation via acute degradation of ARF4 shows an active regulatory role for the GTPase and COPI in anterograde transport. Our data supports a model in which anterograde ER-to-Golgi transport occurs via an ARF4 tubular-vesicular network directly connecting the ER and Golgi-associated pre-cisternae.

cell biology↗

bioRxiv2023

Early steps of multi-receptor viral interactions dissected by high-density, multi-color single molecule mapping in living cells

Direct visualization of the early steps of multi-receptor viral interactions at the singlemolecule level has been largely impeded by the technical challenges associated to imaging individual multi-molecular systems at relevant spatial (nanometer) and temporal (millisecond) scales. Here, we present a four-color, high-density single-molecule spatiotemporal mapping methodology to capture real-time interactions between individual viruses and three different viral (co-)receptors on the membrane of living immune cells derived from donors. Together with quantitative tools, our approach revealed the existence of a coordinated spatiotemporal diffusion of the three different (co-)receptors prior to viral-engagement. By varying the temporal-windows of cumulated single-molecule localizations, we discovered that such a concerted diffusion impacts on the residence time of viruses on the host membrane and potential viral infectivity. Overall, our methodology opens a new door to the systematic analysis of the initial steps of viralhost interactions and paves the way to the investigation of other multi-molecular systems at the single-molecule level.

biophysics↗