Biology subjects

Escribano, J.

Publications and source records attributed to Escribano, J..

4 recordsLinked to original sources

bioRxiv2025

Zebrafish adamtsl4 knockout recapitulates key features of human ADAMTSL4-related diseases: a gene involved in extracellular matrix organization, cell junctions and development

Loss-of-function mutations in ADAMTSL4, a gene encoding an extracellular matrix-associated protein with incompletely understood biological roles, are linked to autosomal recessive disorders predominantly characterized by lens dislocation. Pupil ectopia, increased intraocular pressure, retinal detachment, cataracts, and skeletal abnormalities are also observed in some patients. To investigate ADAMTSL4 biology and related diseases we established a zebrafish knockout line using CRISPR/Cas9 genome editing. The generated zebrafish model harboured the c.234-351del mutation in adamstsl4, reducing its mRNA levels by 75% in 6 days post fertilization (dpf) larvae, and predicting to produce an inactive protein (p.(Gln78Hisfs*127)). Forty percent of F3 knockout larvae (6 dpf) displayed lethal phenotypes characterized by multiple ocular and non-ocular developmental defects, including pericardial, perivitelline and periocular edema, absence of swim bladder, craniofacial malformations and microphthalmia. The remaining 60% larvae survived and displayed only reduced pupil area, indicating incomplete penetrance of the lethality. Histology revealed extracellular matrix (ECM) and intercellular junctions abnormalities within the cornea, iris, lens, and retinal pigment epithelium (RPE). Adult knockout zebrafish (6 months) presented phenotypes resembling ectopia lentis et pupillae and craniosynostosis, with optical defects in the lens and impaired visual function. ECM and cell junction disorganization in the cornea, lens and RPE were also present in these animals. Transcriptomic analysis revealed disrupted expression of genes involved in development, ECM and cell junctions among other biological processes. These findings show that adamtsl4 recapitulates key features of human ADAMTSL4-related disorders and that this gene is essential for normal ECM structure, cell junctions and embryonic development. HighlightsO_LIZebrafish adamtsl4 knockout recapitulates human ADAMTSL4-related phenotypes. C_LIO_LIadamtsl4 is involved in embryonic development. C_LIO_LIadamtsl4 participates in ECM organization and cell adhesion. C_LI

genetics↗

bioRxiv2021

Modeling the three-way feedback between cellular contractility, actin polymerization, and adhesion turnover resolves the contradictory effects of RhoA and Rac1 on endothelial junction dynamics

The formation and recovery of gaps in the vascular endothelium governs a wide range of physiological and pathological phenomena, from angiogenesis to atherosclerosis and tumor cell extravasation. However, the interplay between the mechanical and signaling processes that drive dynamic behavior in vascular endothelial cells is not well understood. In this study, we propose a chemo-mechanical model to investigate the maintenance of endothelial junctions as dependent on the crosstalk between actomyosin contractility, VE-cadherin bond turnover, and actin polymerization, which mediate the forces exerted on the cell-cell interface. Our theoretical model reveals that active cell tension can stabilize cadherin bonds within an adhesion, but excessive RhoA signaling can drive bond dissociation and junction failure. While Rac1-mediated actin polymerization aids gap closure, high levels of Rac1 may also facilitate junction weakening. Combining the modeling framework with novel experiments, we identify how dynamic rupture and heal cycles emerge and, further, describe why gaps tend to localize at multi-cell contacts. Beyond, our analysis also indicates that a critical balance between RhoA and Rac1 expression is required to maintain junction stability and limit endothelial dysfunction. The model predicts how pharmacological modulation of actin polymerization and cell contractility impacts junction stability, with predictions subsequently validated experimentally. Our proposed framework can help guide the development of therapeutics that target the Rho family of GTPases and downstream active mechanical processes.

biophysics↗

bioRxiv2020

Knockout of myoc reveals the role of myocilin in zebrafish sex determination associated with Wnt signalling downregulation

Myocilin is a secreted glycoprotein with a poorly understood biological function and it is mainly known for its association with glaucoma. To explore the normal role of this protein in vivo we developed a myoc knockout (KO) zebrafish line using CRISPR/Cas9 genome editing. This line carries a homozygous variant (c.236_239delinsAAAGGGGAAGGGGA) that is predicted to result in a loss-of-function of the protein because of a premature termination codon p.(V75EfsX60) that resulted in a significant reduction of myoc mRNA levels. Immunohistochemistry showed the presence of myocilin in wild-type embryonic (96 hours post-fertilization) anterior segment eye structures and caudal muscles. The protein was also detected in different adult ocular and non-ocular tissues. No gross macroscopic or microscopic alterations were identified in the KO zebrafish, but remarkably, we observed absence of females among the adult KO animals and apoptosis in the immature juvenile gonad (28 dpf) of these animals, which is characteristic of male development. Transcriptomic analysis showed that adult KO males overexpressed key genes involved in male sex determination and presented differentially expressed Wnt signalling genes. These results show that myocilin is required for ovary differentiation in zebrafish and provide in vivo support for the role of myocilin as a Wnt signalling pathway modulator. In summary, this myoc KO zebrafish line can be useful to investigate the elusive function of this protein, and it provides evidence for the unexpected function of myocilin as a key factor in zebrafish sex determination.

genetics↗

bioRxiv2018

Balance of Mechanical Forces Drives Endothelial Gap Formation and May Facilitate Cancer and Immune-Cell Extravasation

The formation of gaps in the endothelium is a crucial process underlying both cancer and immune cell extravasation, contributing to the functioning of the immune system during infection, the unfavorable development of chronic inflammation and tumor metastasis. Here, we present a stochastic-mechanical multiscale model of an endothelial cell monolayer and show that the dynamic nature of the endothelium leads to spontaneous gap formation, even without intervention from the transmigrating cells. These gaps preferentially appear at the vertices between three endothelial cells, as opposed to the border between two cells. We quantify the frequency and lifetime of these gaps, and validate our predictions experimentally. Interestingly, we find experimentally that cancer cells also preferentially extravasate at vertices, even when they first arrest on borders. This suggests that extravasating cells, rather than initially signaling to the endothelium, might exploit the autonomously forming gaps in the endothelium to initiate transmigration.

bioengineering↗