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Biology subjects

Serini, G.

Publications and source records attributed to Serini, G..

3 recordsLinked to original sources

MT4-MMP/NRP1 axis is required for balanced angiogenesis in the embryonic brain

Angiogenesis is essential for embryonic brain development and tissue repair, yet the mechanisms that spatiotemporally coordinate endothelial behavior to ensure balanced vascular remodeling remain elusive. Here, we identify the glycosylphosphatidylinositol (GPI)-anchored protease MT4-MMP as a critical, context-dependent determinant of angiogenic growth. Global loss of MT4-MMP transiently impairs vascular network formation in the embryonic hindbrain, whereas endothelial-specific deletion triggers an aberrant angiogenesis characterized by increased vessel density, branching, and a profound loss of vascular organization. This dual phenotype reveals MT4-MMP as a fundamental coordinator of neurovascular development. Consistently, MT4-MMP expression was dynamically regulated during wound repair, and its absence amplifies angiogenesis and accelerates wound closure in adult skin, highlighting its role in maintaining vascular homeostasis postnatally. Mechanistically, MT4-MMP-deficient endothelial cells exhibit impaired polarization and sustained, rather than transient, VEGFA-induced ERK activation. We identify NRP1 as a novel substrate of MT4-MMP and demonstrate that MT4-MMP-mediated NRP1 cleavage restricts NRP1 surface availability to tune the intensity of VEGFA signaling. Furthermore, pharmacological blockade of VEGFA-NRP1 binding partially rescues the vascular defects caused by endothelial MT4-MMP loss in vivo. Together, these findings uncover the MT4-MMP/NRP1 axis as a pivotal control point that prevents aberrant vessel expansion, establishing membrane-anchored proteolysis as a primary regulator across developmental and reparative contexts. TeaserThe proteolytic constraint exerted by MT4-MMP dictates neurovascular development and wound repair through the spatial control of NRP1-VEGFA signaling.

cell biology↗

WHEP Domain of Glycyl-tRNA Synthetase Regulates Neuropilin 1 Binding and Vascular Permeability

AbstractAminoacyl-tRNA synthetases (aaRSs) charge tRNAs with their cognate amino acids, ensuring accurate translation of the genetic code from mRNA to protein. During eukaryotic evolution, aaRSs acquired additional domains with unclear functions, including the WHEP domain, a two-helix bundle found in several eukaryotic aaRSs such as glycyl-tRNA synthetase (GlyRS, encoded by GARS1). We generated Gars1{Delta}WHEP mutant mice lacking exon 2, which disrupts most of the WHEP domain. Homozygous Gars1{Delta}WHEP/{Delta}WHEP mice exhibited late embryonic or neonatal lethality, with delayed lung development, characterized by reduced airway dilation (inflatability), and increased vascular leakage. Disruption of the WHEP domain did not impair tRNA aminoacylation but inhibited the free release of GlyRS from cells. Instead, GlyRS{Delta}WHEP was found in the membrane fractions and showed a stronger interaction with the extracellular region of neuropilin 1 (Nrp1) receptor compared to full-length GlyRS. This aberrant interaction enhanced Nrp1s endocytic activity and significantly reduced the localization of the Nrp1 interactor VE-cadherin at the adherens junctions of endothelial cells. A heterozygous knockout of Nrp1 in the Gars1 {Delta}WHEP/{Delta}WHEP mice partially rescued body weight and vascular permeability defects. This study establishes a physiological role for the GlyRS WHEP domain in lung development and its regulation of GlyRS-Nrp1 interaction and vascular permeability.

molecular biology↗

OmniReprodubileCellAnalysis: a comprehensive toolbox for the analysis of cellular biology data.

Open science and reproducibility are two key pillars of modern scientific research. Open science is making scientific research and data accessible and transparent to the broader scientific community and the public. Reproducibility, on the other hand, is the ability to replicate and confirm research results by following the same methods and procedures. Reproducibility is thus crucial because it ensures the reliability and validity of scientific findings. The relationship between open science and reproducibility is intertwined; indeed open science practices, such as sharing raw data, detailed methodologies, and code, greatly facilitate the reproducibility of research. In recent years, concerns about the reproducibility of scientific research have gained prominence, and indeed scientists still lament the lack of details in the methods sections of published papers and the unavailability of raw data from the authors. To assist cellular biologists and immunologists and to promote a more transparent, open and reproducible research practice, we developed OmniReproducibleCellAnalysis (ORCA), a new Shiny Application based in R, for the semi-automated analysis of Western Blot (WB), Reverse Transcription-quantitative PCR (RT-qPCR), Enzyme-Linked ImmunoSorbent Assay (ELISA), Endocytosis and Cytotoxicity experiments. ORCA is open-source and approachable by scientists without advanced R language knowledge. Our application automatically compiles a report containing the finalized data analysis and all its preliminary and intermediate steps, ensuring data analysis standardization and reproducibility. Furthermore, ORCA allows to upload raw data and results directly on the data repository Harvard Dataverse, a valuable tool for promoting transparency and data accessibility in scientific research. By employing ORCA, scientists will cut down analysis time and human-dependent errors, while taking a step towards a research practice compliant with Open Science and FAIR principle.

bioinformatics↗