3D Tissue elongation via ECM stiffness-cued junctional remodeling

ABSTRACTOrgans are sculpted by extracellular as well as cell-intrinsic forces, but how collective cell dynamics are orchestrated in response to microenvironmental cues is poorly understood. Here we apply advanced image analysis to reveal ECM-responsive cell behaviors that drive elongation of the Drosophila follicle, a model 3D system in which basement membrane stiffness instructs tissue morphogenesis. Through in toto morphometric analyses of WT and ‘round egg’ mutants, we find that neither changes in average cell shape nor oriented cell division are required for appropriate organ shape. Instead, a major element is a reorientation of elongated cells at the follicle anterior. Polarized reorientation is regulated by mechanical cues from the basement membrane, which are transduced by the Src tyrosine kinase to alter junctional E-cadherin trafficking. This mechanosensitive cellular behavior represents a conserved mechanism that can elongate ‘edgeless’ tubular epithelia in a process distinct from those that elongate bounded, planar epithelia.

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Filtration by superficial and deep glomeruli of normovolemic and volume-depleted rats

AJP Renal Physiology ◽

10.1152/ajprenal.1986.250.1.f86 ◽

1986 ◽

Vol 250 (1) ◽

pp. F86-F91

Author(s):

R. V. Pinnick ◽

V. J. Savin

Keyword(s):

Basement Membrane ◽

Maximum Rate ◽

Rate Of Change ◽

The Other ◽

Membrane Area ◽

Morphometric Analyses ◽

Three Samples ◽

Glomerular Size ◽

Glomerular Ultrafiltration

We measured glomerular ultrafiltration coefficient (Kf) of isolated superficial (S) and deep (D) glomeruli of normovolemic and volume-depleted rats. Filtration was induced in vitro, and Kf was calculated from the maximum rate of change in glomerular size. Basement membrane area (A) for each glomerulus was estimated from morphometric analyses, and glomerular capillary hydraulic conductivity (Lp) was calculated by the formula Lp = Kf/A. Kf of S and D glomeruli of normovolemic rats were 2.98 +/- 0.98 and 4.25 +/- 0.07 nl . min-1 . mmHg-1, respectively. In hypovolemic rats, Kf of S glomeruli fell by approximately 50% to 1.52 +/- 0.14 nl . min-1 . mmHg-1 (P less than 0.001), whereas Kf of D glomeruli remained unchanged at 4.28 +/- 0.10 nl . min-1 . mmHg-1. Lp, calculated using the peripheral capillary area, averaged 1.98 +/- 0.09 and 1.98 +/- 0.06 microliter . min-1 . mmHg-1 . cm-2 in S and D glomeruli of normovolemic rats and 1.89 +/- 0.11 microliter . min-1 . mmHg-1 . cm-2 in D glomeruli of hypovolemic rats. Lp of S glomeruli of volume-depleted rats (0.90 +/- 0.03 microliter . min-1 . mmHg-1 . cm-2) was lower than in any of the other three samples. Mild hypovolemia causes the Kf of S glomeruli to decline, whereas Kf of D glomeruli remains constant. The decrease in Kf occurs without an alteration in capillary area and is most likely due to a decrease in Lp.

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Long-term, in toto live imaging of the developing mouse heart

10.21203/rs.2.21499/v1 ◽

2020 ◽

Cited By ~ 1

Author(s):

Yanzhu Yue ◽

Xin Li ◽

Youdong Zhang ◽

Aibin He

Keyword(s):

Imaging System ◽

Light Sheet ◽

Live Imaging ◽

Mouse Heart ◽

Cell Behaviors ◽

Oriented Cell Division ◽

Lower Vertebrates ◽

Imaging Strategy ◽

Cell Intercalation ◽

Gated Imaging

Abstract Mapping holistic cell behaviors sculpting mammalian heart has been a goal, but so far only successes in transparent invertebrates and lower vertebrates. Using a live-imaging system comprising a customized vertical light-sheet microscope equipped with a culture module, a heartbeat-gated imaging strategy, and a digital image processing framework, we realized imaging of developing mouse hearts with uninterrupted cell lineages for up to 1.5 days. Four-dimensional landscapes of cell behaviors revealed a blueprint for ventricle chamber formation in which biased outward migration of outermost cardiomyocytes coupled with cell intercalation and horizontal division. The trabeculae, an inner muscle architecture, was developed through early fate segregation and transmural cell arrangement involving both oriented cell division and directional migration. Thus, live-imaging reconstruction affords a transformative means for deciphering mammalian organogenesis.

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Channel Geometry Effects on Red Blood Cell Dynamics and the Resulting ATP Release

ASME 2010 Summer Bioengineering Conference, Parts A and B ◽

10.1115/sbc2010-19359 ◽

2010 ◽

Author(s):

Alison M. Forsyth ◽

Philip D. Owrutsky ◽

Jiandi Wan ◽

Howard A. Stone

Keyword(s):

High Speed ◽

Cell Tracking ◽

Enzymatic Reaction ◽

Atp Release ◽

Microfluidic Channels ◽

Dynamical Response ◽

Functional Difference ◽

Cell Dynamics ◽

Dynamic Behaviors ◽

Cell Behaviors

In shear flow, red blood cells (RBCs) exhibit a variety of dynamic behaviors such as translation, tumbling, swinging, and tank-treading. The physiological consequences of these dynamic behaviors, however, are unknown. For example, how different cell dynamics, be it translation, tumbling, or tank-treading relate to ATP release and how these dynamics are altered by pathological geometries such as constrictions and plaque formations at asymmetric bifurcations are not known. Using microfluidic channels to mimic pathological geometries and RBCs with attached carboxylate beads, to follow any relevant motion, we are able to quantify the dynamical response of red cells to specific pathological geometries with in vitro models. Further, by using an ATP-luciferase enzymatic reaction we set out to determine if there is a functional difference, via chemical release, in cell behaviors. Previously, we correlated RBC deformation and ATP release (Wan et al, PNAS 2008) which in vivo is known to stimulate nitric oxide production, leading to vasodilation. High-speed video and a probability-based cell tracking algorithm make it possible to study large numbers of cells. Preliminary experiments have shown that when cells enter a constriction, there are increased instances of tumbling along constriction wall, while cells more central in the constriction are aligned and deformed by the entrance flow. The relation between the observed cell behaviors and resulting ATP release will be reported.

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Cell Shape and Surface Colonisation in the Diatom Genus Cocconeis—An Opportunity to Explore Bio-Inspired Shape Packing?

Biomimetics ◽

10.3390/biomimetics4020029 ◽

2019 ◽

Vol 4 (2) ◽

pp. 29 ◽

Cited By ~ 2

Author(s):

Timothy Sullivan

Keyword(s):

Cell Shape ◽

Energy Use ◽

Close Association ◽

Packing Fraction ◽

Epifluorescence Microscopy ◽

Theoretical Modelling ◽

Average Cell ◽

Optimal Packing ◽

Immersed Surfaces ◽

Diatom Genus

Optimal packing of 2 and 3-D shapes in confined spaces has long been of practical and theoretical interest, particularly as it has been discovered that rotatable ellipses (or ellipsoids in the 3-D case) can, for example, have higher packing densities than disks (or spheres in the 3-D case). Benthic diatoms, particularly those of the genus Cocconeis (Ehr.)—which are widely regarded as prolific colonisers of immersed surfaces—often have a flattened (adnate) cell shape and an approximately elliptical outline or “footprint” that allows them to closely contact the substratum. Adoption of this shape may give these cells a number of advantages as they colonise surfaces, such as a higher packing fraction for colonies on a surface for more efficient use of limited space, or an increased contact between individual cells when cell abundances are high, enabling the cells to minimize energy use and maximize packing (and biofilm) stability on a surface. Here, the outline shapes of individual diatom cells are measured using scanning electron and epifluorescence microscopy to discover if the average cell shape compares favourably with those predicted by theoretical modelling of efficient 2-D ellipse packing. It is found that the aspect ratio of measured cells in close association in a biofilm—which are broadly elliptical in shape—do indeed fall within the range theoretically predicted for optimal packing, but that the shape of individual diatoms also differ subtly from that of a true ellipse. The significance of these differences for optimal packing of 2-D shapes on surfaces is not understood at present, but may represent an opportunity to further explore bio-inspired design shapes for the optimal packing of shapes on surfaces.

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A developmental biologist’s “outside-the-cell” thinking

The Journal of Cell Biology ◽

10.1083/jcb.201501083 ◽

2015 ◽

Vol 210 (3) ◽

pp. 369-372 ◽

Cited By ~ 12

Author(s):

David R. Sherwood

Keyword(s):

Extracellular Matrix ◽

Basement Membrane ◽

Recent Work ◽

Cell Biology ◽

Developmental Systems ◽

Support Structure ◽

Cell Behaviors ◽

Direct Cell ◽

Surrounding Extracellular Matrix

A major gap in our understanding of cell biology is how cells generate and interact with their surrounding extracellular matrix. Studying this problem during development has been particularly fruitful. Recent work on the basement membrane in developmental systems is transforming our view of this matrix from one of a static support structure to that of a dynamic scaffold that is regularly remodeled to actively shape tissues and direct cell behaviors.

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Thigmotropism of Malignant Melanoma Cells

Dermatology Research and Practice ◽

10.1155/2012/362784 ◽

2012 ◽

Vol 2012 ◽

pp. 1-6 ◽

Cited By ~ 4

Author(s):

Pascale Quatresooz ◽

Claudine Piérard-Franchimont ◽

Fanchon Noël ◽

Gérald E. Piérard

Keyword(s):

Malignant Melanoma ◽

Basement Membrane ◽

Growth Model ◽

Growth Phase ◽

Sweat Gland ◽

Cell Shape ◽

Hair Follicles ◽

Perivascular Space ◽

Primary Neoplasm ◽

Contact Sensing

During malignant melanoma (MM) progression including incipient metastasis, neoplastic cells follow some specific migration paths inside the skin. In particular, they progress along the dermoepidermal basement membrane, the hair follicles, the sweat gland apparatus, nerves, and the near perivascular space. These features evoke the thigmotropism phenomenon defined as a contact-sensing growth of cells. This process is likely connected to modulation in cell tensegrity (control of the cell shape). These specifically located paucicellular aggregates of MM cells do not appear to be involved in the tumorigenic growth phase, but rather they participate in the so-called “accretive” growth model. These MM cell collections are often part of the primary neoplasm, but they may, however, correspond to MM micrometastases and predict further local overt metastasis spread.

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Estimation of average cell shape from digital images of cellular surfaces

First Canadian Conference on Computer and Robot Vision, 2004. Proceedings. ◽

10.1109/cccrv.2004.1301455 ◽

2004 ◽

Cited By ~ 1

Author(s):

P.J.W. Iles ◽

D.A. Clausi ◽

G.W. Brodland

Keyword(s):

Cell Shape ◽

Digital Images ◽

Average Cell

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Cardiac function modulates endocardial cell dynamics to shape the cardiac outflow tract

10.1101/787358 ◽

2019 ◽

Cited By ~ 1

Author(s):

Pragya Sidhwani ◽

Giulia L.M. Boezio ◽

Hongbo Yang ◽

Neil C. Chi ◽

Beth L. Roman ◽

...

Keyword(s):

Cardiac Function ◽

Outflow Tract ◽

Cell Dynamics ◽

Cell Behaviors ◽

Cell Accumulation ◽

Tgfβ Receptor ◽

Heart Formation ◽

Physical Forces ◽

Endocardial Cell ◽

Cardiac Outflow

ABSTRACTPhysical forces are important participants in the cellular dynamics that shape developing organs. During heart formation, for example, contractility and blood flow generate biomechanical cues that influence patterns of cell behavior. Here, we address the interplay between function and form during the assembly of the cardiac outflow tract (OFT), a crucial connection between the heart and vasculature that develops while circulation is underway. In zebrafish, we find that the OFT expands via accrual of both endocardial and myocardial cells. However, when cardiac function is disrupted, OFT endocardial growth ceases, accompanied by reduced proliferation and reduced addition of cells from adjacent vessels. The TGFβ receptor Acvrl1 is required for addition of endocardial cells, but not for their proliferation, indicating distinct regulation of these essential cell behaviors. Together, our results suggest that cardiac function modulates OFT morphogenesis by triggering endocardial cell accumulation that induces OFT lumen expansion and shapes OFT dimensions.

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The basement membrane as a structured surface – role in vascular health and disease

Journal of Cell Science ◽

10.1242/jcs.239889 ◽

2020 ◽

Vol 133 (18) ◽

pp. jcs239889

Author(s):

Claire Leclech ◽

Carlo F. Natale ◽

Abdul I. Barakat

Keyword(s):

Basement Membrane ◽

Biochemical Composition ◽

Vascular Tissue ◽

Cell Structure ◽

Mechanical Stiffness ◽

Cellular Behavior ◽

Structured Surface ◽

Health And Disease ◽

And Function ◽

Biophysical Attributes

ABSTRACTThe basement membrane (BM) is a thin specialized extracellular matrix that functions as a cellular anchorage site, a physical barrier and a signaling hub. While the literature on the biochemical composition and biological activity of the BM is extensive, the central importance of the physical properties of the BM, most notably its mechanical stiffness and topographical features, in regulating cellular function has only recently been recognized. In this Review, we focus on the biophysical attributes of the BM and their influence on cellular behavior. After a brief overview of the biochemical composition, assembly and function of the BM, we describe the mechanical properties and topographical structure of various BMs. We then focus specifically on the vascular BM as a nano- and micro-scale structured surface and review how its architecture can modulate endothelial cell structure and function. Finally, we discuss the pathological ramifications of the biophysical properties of the vascular BM and highlight the potential of mimicking BM topography to improve the design of implantable endovascular devices and advance the burgeoning field of vascular tissue engineering.

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