Biology subjects

Iruela-Arispe, M. L.

Publications and source records attributed to Iruela-Arispe, M. L..

6 recordsLinked to original sources

bioRxiv2025

Scrib organizes cortical actomyosin clusters to maintain adherens junctions and angiogenic sprouting

Spatiotemporal control of adherens junction fluidity and integrity is critical for angiogenesis, but underlying mechanisms are incompletely understood. To identify unappreciated regulators of endothelial adherens junctions, we performed VE-cadherin proximity ligation mass spectrometry, revealing significant interaction with the multifunctional scaffold Scrib. Utilizing a 3D angiogenesis-on-chip model, we find Scrib-depleted microvessels generate reduced intact sprouts and increased single-cell detachments. This defect was characterized by adherens junction instability and decreased actomyosin in the junctional cortex, yet was not caused by changes in catenin-dependent VE-cadherin coupling to actin. Instead, Scrib controls the formation of cortical actomyosin clusters, which critically organize the architecture and dynamics of the junctional actomyosin cortex to promote adherens junction stability. We further discovered that unconventional myosin-1c is a critical effector linking Scrib cortical dynamics and VE-cadherin to stabilize adherens junctions during angiogenic initiation. Our results demonstrate a new role for Scrib directing cortical actomyosin organization that is critical for precise control of adherens junctions during angiogenesis.

cell biology↗

bioRxiv2025

Zonal endothelial cell heterogeneity underlies murine renal vascular development.

The renal vasculature consists of highly specialized blood vessels that carry out distinct physiological functions. Defining their transcriptional signatures and tracing their developmental ontogeny has thus far been challenging due to a lack of regionally specific endothelial biomarkers. Here, we performed single nuclear RNA sequencing (snucRNA-Seq) to interrogate embryonic renal endothelial cells. We identified nine different endothelial cell types, and validated expression of novel candidates using multiplex RNAScope. We interrogate biological characteristics, including cell cycle stage, of developmental blood vessels with a variety of in vivo tools. Using genetic tools based on expression of tip cell marker Esm1, we performed detailed lineage tracing, demonstrating multi-clonal and multi-directional endothelial contribution to glomerular vasculature. Together, this study provides the first validated, tool-focused developmental atlas of the murine renal vasculature and elucidates several novel cellular mechanisms of nephron vascularization.

developmental biology↗

bioRxiv2024

Resolving the design principles that control postnatal vascular growth and scaling

After birth, tissues grow continuously until reaching adult size, with each organ exhibiting unique cellular dynamics, growth patterns, and (stem or non-stem) cell sources. Using a suite of experimental and computational multiscale approaches, we found that aortic expansion is guided by specific biological principles and scales with the vertebral column rather than animal body weight. Expansion proceeds via two distinct waves of arterial cell proliferation along blood flow that are spatially stochastic, yet temporally coordinated. Each wave exhibits unique cell cycle kinetics and properties, with the first wave exhibiting cell cycle durations as fast as 6 hours. Single-cell RNA sequencing showed changes in fatty acid metabolism concomitant with an increase in cell size. Mathematical modeling and experiments indicated endothelial cell extrusion is essential for homeostatic aortic growth and balancing excess proliferation. In a genetic model of achondroplasia, the aorta achieves proper scaling through enhanced cell extrusion while maintaining normal proliferation dynamics. Collectively, these results provide a blueprint of the principles that orchestrate aortic growth which depends entirely on differentiated cell proliferation rather than resident stem cells.

developmental biology↗

bioRxiv2024

Spatiotemporal dynamics of primary and motile cilia throughout lung development

Cilia are specialized structures found on a variety of mammalian cells, with variable roles in the transduction of mechanical and biological signals (by primary cilia, PC), as well as the generation of fluid flow (by motile cilia). Their critical role in the establishment of a left-right axis in early development is well described, as is the innate immune function of multiciliated upper airway epithelium. By contrast, the dynamics of ciliary status during organogenesis and postnatal development is largely unknown. In this study, we define the progression of ciliary status within the endothelium, epithelium, and mesenchyme of the lung. Remarkably, we find that endothelial cells (ECs) lack PC at all stages of development, except in low numbers in the most proximal portions of the pulmonary arteries. In the lung epithelium, a proximodistal ciliary gradient is established over time, as the uniformly mono-ciliated epithelium transitions into proximal, multiciliated cells, and the distal alveolar epithelium loses its cilia. Mesenchymal cells, interestingly, are uniformly ciliated in early development, but with restriction to PDGFR+ fibroblasts in the adult alveoli. This dynamic process in multiple cellular populations both challenges prior assertions that PC are found on all cells, and highlights a need to understand their spatiotemporal functions. HighlightsO_LIPrimary cilia are found broadly throughout early embryonic tissues. C_LIO_LIPrimary cilia are observed in both epithelial and mesenchymal cells in the early lung. C_LIO_LIPulmonary endothelial cells largely do not possess primary cilia during embryonic development. C_LIO_LIDifferential multiciliation and loss of epithelial cilia in a proximal-distal axis. C_LIO_LIMaintenance of cilia in adult pulmonary PDGFR+ fibroblasts. C_LI

developmental biology↗

bioRxiv2021

Transcriptional evaluation of the ductus arteriosus at the single-cell level uncovers a requirement for vimentin for complete closure

OBJECTIVEFailure to close the ductus arteriosus immediately post-birth, patent ductus arteriosus (PDA), accounts for up to 10% of all congenital heart defects. Despite significant advances in PDA management options, including pharmacological treatment targeting the prostaglandin pathway, a proportion of patients fail to respond and must undergo surgical intervention. Thus, further refinement of the cellular and molecular mechanisms that govern vascular remodeling of this vessel is required. APPROACH AND RESULTSAs anticipated, single-cell RNA sequencing on the ductus arteriosus in mouse embryos at E18.5, P0.5, and P5, revealed broad transcriptional alterations in the endothelial, smooth muscle, and fibroblast cell compartments. Making use of these data sets, vimentin emerged as an interesting candidate for further investigation. Subsequent studies demonstrated that, in fact, mice with genetic deletion of vimentin fail to complete vascular remodeling of the ductus arteriosus, as per presence of a functional lumen. CONCLUSIONSThrough single-cell RNA-sequencing and by tracking closure of the ductus arteriosus postnatally in mice, we uncovered the unexpected contribution of vimentin in driving complete closure of the ductus arteriosus potentially through regulation of the Notch signaling pathway. HIGHLIGHTSO_LISingle-cell RNA-sequencing on the ductus arteriosus at E18.5, P0.5, and P5 reveals how the ductus arteriosus undergoes drastic transcriptional changes at the single-cell level. C_LIO_LIEndothelial cells increase levels of Vimentin, Notch1 and Jag1 transcripts soon after birth (P0.5), concurrent with ductus arteriosus closure. C_LIO_LILoss of vimentin, the major intermediate filament protein of endothelial cells, prevents proper permanent closure of the ductus arteriosus. C_LI

developmental biology↗

bioRxiv2020

Single Cell and Spatial Transcriptomics Defines the Cellular Architecture of the Antimicrobial Response Network in Human Leprosy Granulomas

Granulomas are complex cellular structures comprised predominantly of macrophages and lymphocytes that function to contain and kill invading pathogens. Here, we investigated single cell phenotypes associated with antimicrobial responses in human leprosy granulomas by applying single cell and spatial sequencing to leprosy biopsy specimens. We focused on reversal reactions (RR), a dynamic process in which some patients with disseminated lepromatous leprosy (L-lep) transition towards self-limiting tuberculoid leprosy (T-lep), mounting effective antimicrobial responses. We identified a set of genes encoding proteins involved in antimicrobial responses that are differentially expressed in RR versus L-lep lesions, and regulated by IFN-{gamma} and IL-1{beta}. By integrating the spatial coordinates of the key cell types and antimicrobial gene expression in RR and T-lep lesions, we constructed a map revealing the organized architecture of granulomas depicting compositional and functional layers by which macrophages, T cells, keratinocytes and fibroblasts contribute to the antimicrobial response.

immunology↗