1
|
Gredler ML, Zallen JA. Multicellular rosettes link mesenchymal-epithelial transition to radial intercalation in the mouse axial mesoderm. Dev Cell 2023:S1534-5807(23)00134-X. [PMID: 37080203 DOI: 10.1016/j.devcel.2023.03.018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2022] [Revised: 01/25/2023] [Accepted: 03/24/2023] [Indexed: 04/22/2023]
Abstract
Mesenchymal-epithelial transitions are fundamental drivers of development and disease, but how these behaviors generate epithelial structure is not well understood. Here, we show that mesenchymal-epithelial transitions promote epithelial organization in the mouse node and notochordal plate through the assembly and radial intercalation of three-dimensional rosettes. Axial mesoderm rosettes acquire junctional and apical polarity, develop a central lumen, and dynamically expand, coalesce, and radially intercalate into the surface epithelium, converting mesenchymal-epithelial transitions into higher-order tissue structure. In mouse Par3 mutants, axial mesoderm rosettes establish central tight junction polarity but fail to form an expanded apical domain and lumen. These defects are associated with altered rosette dynamics, delayed radial intercalation, and formation of a small, fragmented surface epithelial structure. These results demonstrate that three-dimensional rosette behaviors translate mesenchymal-epithelial transitions into collective radial intercalation and epithelial formation, providing a strategy for building epithelial sheets from individual self-organizing units in the mammalian embryo.
Collapse
Affiliation(s)
- Marissa L Gredler
- Howard Hughes Medical Institute and Developmental Biology Program, Sloan Kettering Institute, New York, NY, USA
| | - Jennifer A Zallen
- Howard Hughes Medical Institute and Developmental Biology Program, Sloan Kettering Institute, New York, NY, USA.
| |
Collapse
|
2
|
Abboud Asleh M, Zaher M, Asleh J, Jadon J, Shaulov L, Yelin R, Schultheiss TM. A morphogenetic wave in the chick embryo lateral mesoderm generates mesenchymal-epithelial transition through a 3D- rosette intermediate. Dev Cell 2023:S1534-5807(23)00133-8. [PMID: 37080204 DOI: 10.1016/j.devcel.2023.03.017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2022] [Revised: 02/24/2023] [Accepted: 03/24/2023] [Indexed: 04/22/2023]
Abstract
Formation of epithelia through mesenchymal-epithelial transition (MET) is essential for embryonic development and for many physiological and pathological processes. This study investigates MET in vivo in the chick embryo lateral mesoderm, where a multilayered mesenchyme transforms into two parallel epithelial sheets that constitute the coelomic lining of the embryonic body cavity. Prior to MET initiation, mesenchymal cells exhibit non-polarized distribution of multiple polarity markers, albeit not aPKC. We identified an epithelializing wave that sweeps across the lateral mesoderm, the wavefront of which is characterized by the accumulation of basal fibronectin and a network of 3D rosettes composed of polarized, wedge-shaped cells surrounding a central focus of apical markers, now including aPKC. Initiation of the MET process is dependent on extracellular matrix-integrin signaling acting through focal adhesion kinase and talin, whereas progression through the rosette phase requires aPKC function. We present a stepwise model for MET, comprising polarization, 3D-rosette, and epithelialization stages.
Collapse
Affiliation(s)
- Manar Abboud Asleh
- Department of Genetics and Developmental Biology, Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa 31096, Israel
| | - Mira Zaher
- Department of Genetics and Developmental Biology, Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa 31096, Israel
| | - Jad Asleh
- Department of Genetics and Developmental Biology, Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa 31096, Israel
| | - Julian Jadon
- Department of Genetics and Developmental Biology, Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa 31096, Israel
| | - Lihi Shaulov
- Department of Genetics and Developmental Biology, Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa 31096, Israel
| | - Ronit Yelin
- Department of Genetics and Developmental Biology, Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa 31096, Israel
| | - Thomas M Schultheiss
- Department of Genetics and Developmental Biology, Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa 31096, Israel.
| |
Collapse
|
3
|
Lee WC, Russell B, Rénia L. Evolving perspectives on rosetting in malaria. Trends Parasitol 2022; 38:882-889. [PMID: 36031553 DOI: 10.1016/j.pt.2022.08.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2022] [Revised: 08/01/2022] [Accepted: 08/01/2022] [Indexed: 11/26/2022]
Abstract
The ability of the intraerythrocytic Plasmodium spp. to form spontaneous rosettes with uninfected red blood cells (URBCs) has been observed in the medically important malaria parasites. Since the discovery of rosettes in the late 1980s, different formation mechanisms and pathobiological roles have been postulated for rosetting; most of which have focused on Plasmodium falciparum. Recent breakthroughs, including new data from Plasmodium vivax, have highlighted the multifaceted roles of rosetting in the immunopathobiology and the development of drug resistance in human malaria. Here, we provide new perspectives on the formation and the role of rosetting in malaria rheopathobiology.
Collapse
Affiliation(s)
- Wenn-Chyau Lee
- Department of Parasitology, Faculty of Medicine, Universiti Malaya, Kuala Lumpur, Malaysia; A*STAR Infectious Diseases Labs, Agency for Science, Technology, and Research (A*STAR), Singapore.
| | - Bruce Russell
- Department of Microbiology and Immunology, University of Otago, Dunedin, Otago, New Zealand
| | - Laurent Rénia
- A*STAR Infectious Diseases Labs, Agency for Science, Technology, and Research (A*STAR), Singapore; Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore; School of Biological Sciences, Nanyang Technological University, Singapore.
| |
Collapse
|
4
|
Chen G, Bhadra BN, Sutrisno L, Shrestha LK, Ariga K. Fullerene Rosette: Two-Dimensional Interactive Nanoarchitectonics and Selective Vapor Sensing. Int J Mol Sci 2022; 23. [PMID: 35628264 DOI: 10.3390/ijms23105454] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2022] [Revised: 05/04/2022] [Accepted: 05/11/2022] [Indexed: 12/24/2022] Open
Abstract
The simplicity of fullerenes as assembled components provides attractive opportunities for basic understanding in self-assembly research. We applied in situ reactive methods to the self-assembly process of C60 molecules with melamine/ethylenediamine components in solution, resulting in a novel type of fullerene assemblies, micron-sized two-dimensional, amorphous shape-regular objects, fullerene rosettes. ATR−FTIR spectra, XPS, and TGA results suggest that the melamine/ethylenediamine components strongly interact and/or are covalently linked with fullerenes in the fullerene rosettes. The broad peak for layer spacing in the XRD patterns of the fullerene rosettes corresponds roughly to the interdigitated fullerene bilayer or monolayer of modified fullerene molecules. The fullerene rosettes are made from the accumulation of bilayer/monolayer assemblies of hybridized fullerenes in low crystallinity. Prototype sensor systems were fabricated upon immobilization of the fullerene rosettes onto surfaces of a quartz crystal microbalance (QCM), and selective sensing of formic acid was demonstrated as preliminary results for social-demanded toxic material sensing. The QCM sensor with fullerene rosette is categorized as one of the large-response sensors among reported examples. In selectivity to formic acids against basic guests (formic acid/pyridine >30) or aromatic guests (formic acid/toluene >110), the fullerene rosette-based QCM sensor also showed superior performance.
Collapse
|
5
|
Lee WC, Shahari S, Nguee SYT, Lau YL, Rénia L. Cytoadherence Properties of Plasmodium knowlesi-Infected Erythrocytes. Front Microbiol 2022; 12:804417. [PMID: 35069511 PMCID: PMC8767020 DOI: 10.3389/fmicb.2021.804417] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Accepted: 11/24/2021] [Indexed: 11/13/2022] Open
Abstract
Plasmodium knowlesi is responsible for zoonotic malaria infections that are potentially fatal. While the severe pathology of falciparum malaria is associated with cytoadherence phenomena by Plasmodium falciparum-infected erythrocytes (IRBC), information regarding cytoadherence properties of P. knowlesi-IRBC remained scarce. Here, we characterized the cytoadherence properties of RBC infected with the laboratory-adapted P. knowlesi A1-H.1 strain. We found that late-stage IRBC formed rosettes in a human serum-dependent manner, and rosettes hampered IRBC phagocytosis. IRBC did not adhere much to unexposed (unstimulated) human endothelial cell lines derived from the brain (hCMEC/D3), lungs (HPMEC), and kidneys (HRGEC). However, after being "primed" with P. knowlesi culture supernatant, the IRBC-endothelial cytoadherence rate increased in HPMEC and HRGEC, but not in hCMEC/D3 cells. Both endothelial cytoadherence and rosetting phenomena were abrogated by treatment of P. knowlesi-IRBC with trypsin. We also found that different receptors were involved in IRBC cytoadherence to different types of endothelial cells. Although some of the host receptors were shared by both P. falciparum- and P. knowlesi-IRBC, the availability of glycoconjugates on the receptors might influence the capacity of P. knowlesi-IRBC to cytoadhere to these receptors.
Collapse
Affiliation(s)
- Wenn-Chyau Lee
- Department of Parasitology, Faculty of Medicine, Universiti Malaya, Kuala Lumpur, Malaysia.,ASTAR Infectious Diseases Labs, Agency for Science, Technology and Research (A*STAR), Singapore, Singapore
| | - Shahhaziq Shahari
- Department of Parasitology, Faculty of Medicine, Universiti Malaya, Kuala Lumpur, Malaysia
| | - Samantha Yee Teng Nguee
- ASTAR Infectious Diseases Labs, Agency for Science, Technology and Research (A*STAR), Singapore, Singapore.,Department of Microbiology & Immunology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Yee-Ling Lau
- Department of Parasitology, Faculty of Medicine, Universiti Malaya, Kuala Lumpur, Malaysia
| | - Laurent Rénia
- ASTAR Infectious Diseases Labs, Agency for Science, Technology and Research (A*STAR), Singapore, Singapore.,Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, Singapore.,School of Biological Sciences, Nanyang Technological University, Singapore, Singapore
| |
Collapse
|
6
|
Ripolles-Garcia A, Holle DM, Cohen JA, Beltran WA, Aguirre GD. Retinal structural and microvascular abnormalities in retinal dysplasia imaged by OCT and OCT angiography. Vet Ophthalmol 2021; 25 Suppl 1:193-200. [PMID: 34808028 DOI: 10.1111/vop.12952] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2021] [Revised: 10/08/2021] [Accepted: 10/22/2021] [Indexed: 11/29/2022]
Abstract
OBJECTIVE To describe the in vivo structural characteristics of multifocal and geographic retinal dysplasia visualized with advanced retinal imaging including confocal scanning laser ophthalmoscopy (cSLO), optical coherence tomography (OCT), en face OCT, and the novel vascular imaging technique OCT angiography (OCTA). DOGS STUDIED AND PROCEDURES Two dogs were diagnosed with unilateral multifocal or geographic retinal dysplasia and underwent advanced retinal imaging under general anesthesia at the Retinal Disease Studies Facility of the University of Pennsylvania. RESULTS In both cases, the morphological pattern of the lesions was similar including outer retinal folds that invaginated and formed tubular retinal rosettes, surrounding a central inner retinal thickening (multifocal) or plaque (geographic). The two dogs had multiple vascular anomalies in the lesions such as increased tortuosity, abnormal change of vessel diameter including aneurysms and capillary network disruption. We also identified increased autofluorescence by AF cSLO with short wavelength light source (488 nm and barrier filter at 500 nm), and several areas of photoreceptor loss associated with the lesions. CONCLUSION The use of OCTA allowed the identification of microvascular abnormalities associated with multifocal and geographic retinal dysplasia in two dogs. To our knowledge, this is the first report where the dye-free OCTA technique is used to study vascular lesions in canine retinas.
Collapse
Affiliation(s)
- Ana Ripolles-Garcia
- Division of Experimental Retinal Therapies, Department of Clinical Sciences & Advanced Medicine, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | | | | | - William A Beltran
- Division of Experimental Retinal Therapies, Department of Clinical Sciences & Advanced Medicine, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Gustavo D Aguirre
- Division of Experimental Retinal Therapies, Department of Clinical Sciences & Advanced Medicine, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| |
Collapse
|
7
|
Pan JW, Antony A, Tal A, Yushmanov V, Fong J, Richardson M, Schirda C, Bagic A, Gonen O, Hetherington HP. MR spectroscopic imaging at 3 T and outcomes in surgical epilepsy. NMR Biomed 2021; 34:e4492. [PMID: 33751687 PMCID: PMC8122073 DOI: 10.1002/nbm.4492] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/22/2020] [Accepted: 01/23/2021] [Indexed: 05/09/2023]
Abstract
For the spectroscopic assessment of brain disorders that require large-volume coverage, the requirements of RF performance and field homogeneity are high. For epilepsy, this is also challenging given the inter-patient variation in location, severity and subtlety of anatomical identification and its tendency to involve the temporal region. We apply a targeted method to examine the utility of large-volume MR spectroscopic imaging (MRSI) in surgical epilepsy patients, implementing a two-step acquisition, comprised of a 3D acquisition to cover the fronto-parietal regions, and a contiguous parallel two-slice Hadamard-encoded acquisition to cover the temporal-occipital region, both with TR /TE = 2000/40 ms and matched acquisition times. With restricted (static, first/second-order) B0 shimming in their respective regions, the Cramér-Rao lower bounds for creatine from the temporal lobe two-slice Hadamard and frontal-parietal 3D acquisition are 8.1 ± 2.2% and 6.3 ± 1.9% respectively. The datasets are combined to provide a total 60 mm axial coverage over the frontal, parietal and superior temporal to middle temporal-occipital regions. We applied these acquisitions at a nominal 400 mm3 voxel resolution in n = 27 pre-surgical epilepsy patients and n = 20 controls. In controls, 86.6 ± 3.2% voxels with at least 50% tissue (white + gray matter, excluding CSF) survived spectral quality inclusion criteria. Since all patients were clinically followed for at least 1 year after surgery, seizure frequency outcome was available for all. The MRSI measurements of the total fractional metabolic dysfunction (characterized by the Cr/NAA metric) in FreeSurfer MRI gray matter segmented regions, in the patients compared with the controls, exhibited a significant Spearman correlation with post-surgical outcome. This finding suggests that a larger burden of metabolic dysfunction is seen in patients with poorer post-surgical seizure control.
Collapse
Affiliation(s)
- Jullie W Pan
- Department of Radiology, University of Pittsburgh, Pittsburgh, Pennsylvania
- Department of Neurology, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Arun Antony
- Department of Neurology, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Assaf Tal
- Department of Chemical and Biological Physics, Weizmann Institute, Rehovot, Israel
| | - Victor Yushmanov
- Department of Radiology, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Joanna Fong
- Department of Neurology, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Mark Richardson
- Department of Neurosurgery, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Claud Schirda
- Department of Radiology, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Anto Bagic
- Department of Neurology, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Oded Gonen
- Department of Radiology, New York University, New York, New York
| | | |
Collapse
|
8
|
Sparvoli D, Lebrun M. Unraveling the Elusive Rhoptry Exocytic Mechanism of Apicomplexa. Trends Parasitol 2021; 37:622-637. [PMID: 34045149 DOI: 10.1016/j.pt.2021.04.011] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2021] [Revised: 04/19/2021] [Accepted: 04/19/2021] [Indexed: 12/11/2022]
Abstract
Apicomplexan parasites are unicellular eukaryotes that invade the cells in which they proliferate. The development of genetic tools in Toxoplasma, and then in Plasmodium, in the 1990s allowed the first description of the molecular machinery used for motility and invasion, revealing a crucial role for two different secretory organelles, micronemes and rhoptries. Rhoptry proteins are injected directly into the host cytoplasm not only to promote invasion but also to manipulate host functions. Nonetheless, the injection machinery has remained mysterious, a major conundrum in the field. Here we review recent progress in uncovering structural components and proteins implicated in rhoptry exocytosis and explain how revisiting early findings and considering the evolutionary origins of Apicomplexa contributed to some of these discoveries.
Collapse
Affiliation(s)
- Daniela Sparvoli
- LPHI UMR5235, Univ Montpellier, CNRS, F-34095 Montpellier, France
| | - Maryse Lebrun
- LPHI UMR5235, Univ Montpellier, CNRS, F-34095 Montpellier, France.
| |
Collapse
|
9
|
Prieto-Colomina A, Fernández V, Chinnappa K, Borrell V. MiRNAs in early brain development and pediatric cancer: At the intersection between healthy and diseased embryonic development. Bioessays 2021; 43:e2100073. [PMID: 33998002 DOI: 10.1002/bies.202100073] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Revised: 04/12/2021] [Accepted: 04/15/2021] [Indexed: 12/15/2022]
Abstract
The size and organization of the brain are determined by the activity of progenitor cells early in development. Key mechanisms regulating progenitor cell biology involve miRNAs. These small noncoding RNA molecules bind mRNAs with high specificity, controlling their abundance and expression. The role of miRNAs in brain development has been studied extensively, but their involvement at early stages remained unknown until recently. Here, recent findings showing the important role of miRNAs in the earliest phases of brain development are reviewed, and it is discussed how loss of specific miRNAs leads to pathological conditions, particularly adult and pediatric brain tumors. Let-7 miRNA downregulation and the initiation of embryonal tumors with multilayered rosettes (ETMR), a novel link recently discovered by the laboratory, are focused upon. Finally, it is discussed how miRNAs may be used for the diagnosis and therapeutic treatment of pediatric brain tumors, with the hope of improving the prognosis of these devastating diseases.
Collapse
Affiliation(s)
- Anna Prieto-Colomina
- Instituto de Neurociencias, Consejo Superior de Investigaciones Científicas & Universidad Miguel Hernández, Sant Joan d'Alacant, Spain
| | - Virginia Fernández
- Neurobiology of miRNA, Fondazione Istituto Italiano di Tecnologia (IIT), Genoa, Italy
| | - Kaviya Chinnappa
- Instituto de Neurociencias, Consejo Superior de Investigaciones Científicas & Universidad Miguel Hernández, Sant Joan d'Alacant, Spain
| | - Víctor Borrell
- Instituto de Neurociencias, Consejo Superior de Investigaciones Científicas & Universidad Miguel Hernández, Sant Joan d'Alacant, Spain
| |
Collapse
|
10
|
Barrett PQ, Guagliardo NA, Bayliss DA. Ion Channel Function and Electrical Excitability in the Zona Glomerulosa: A Network Perspective on Aldosterone Regulation. Annu Rev Physiol 2020; 83:451-475. [PMID: 33176563 DOI: 10.1146/annurev-physiol-030220-113038] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Aldosterone excess is a pathogenic factor in many hypertensive disorders. The discovery of numerous somatic and germline mutations in ion channels in primary hyperaldosteronism underscores the importance of plasma membrane conductances in determining the activation state of zona glomerulosa (zG) cells. Electrophysiological recordings describe an electrically quiescent behavior for dispersed zG cells. Yet, emerging data indicate that in native rosette structures in situ, zG cells are electrically excitable, generating slow periodic voltage spikes and coordinated bursts of Ca2+ oscillations. We revisit data to understand how a multitude of conductances may underlie voltage/Ca2+ oscillations, recognizing that zG layer self-renewal and cell heterogeneity may complicate this task. We review recent data to understand rosette architecture and apply maxims derived from computational network modeling to understand rosette function. The challenge going forward is to uncover how the rosette orchestrates the behavior of a functional network of conditional oscillators to control zG layer performance and aldosterone secretion.
Collapse
Affiliation(s)
- Paula Q Barrett
- Department of Pharmacology, University of Virginia School of Medicine, Charlottesville, Virginia 22908, USA; , ,
| | - Nick A Guagliardo
- Department of Pharmacology, University of Virginia School of Medicine, Charlottesville, Virginia 22908, USA; , ,
| | - Douglas A Bayliss
- Department of Pharmacology, University of Virginia School of Medicine, Charlottesville, Virginia 22908, USA; , ,
| |
Collapse
|
11
|
Mathiah N, Despin-Guitard E, Stower M, Nahaboo W, Eski ES, Singh SP, Srinivas S, Migeotte I. Asymmetry in the frequency and position of mitosis in the mouse embryo epiblast at gastrulation. EMBO Rep 2020; 21:e50944. [PMID: 33016470 DOI: 10.15252/embr.202050944] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2020] [Revised: 08/19/2020] [Accepted: 09/09/2020] [Indexed: 01/06/2023] Open
Abstract
At gastrulation, a subpopulation of epiblast cells constitutes a transient posteriorly located structure called the primitive streak, where cells that undergo epithelial-mesenchymal transition make up the mesoderm and endoderm lineages. Mouse embryo epiblast cells were labelled ubiquitously or in a mosaic fashion. Cell shape, packing, organization and division were recorded through live imaging during primitive streak formation. Posterior epiblast displays a higher frequency of rosettes, some of which associate with a central cell undergoing mitosis. Cells at the primitive streak, in particular delaminating cells, undergo mitosis more frequently than other epiblast cells. In pseudostratified epithelia, mitosis takes place at the apical side of the epithelium. However, mitosis is not restricted to the apical side of the epiblast, particularly on its posterior side. Non-apical mitosis occurs specifically in the streak even when ectopically located. Posterior non-apical mitosis results in one or two daughter cells leaving the epiblast layer. Cell rearrangement associated with mitotic cell rounding in posterior epiblast, in particular when non-apical, might thus facilitate cell ingression and transition to a mesenchymal phenotype.
Collapse
Affiliation(s)
| | | | - Matthew Stower
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, UK
| | - Wallis Nahaboo
- Université Libre de Bruxelles, IRIBHM, Brussels, Belgium
| | - Elif Sema Eski
- Université Libre de Bruxelles, IRIBHM, Brussels, Belgium
| | | | - Shankar Srinivas
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, UK
| | | |
Collapse
|
12
|
Dhangadamajhi G, Singh S. Sphingosine 1-Phosphate in Malaria Pathogenesis and Its Implication in Therapeutic Opportunities. Front Cell Infect Microbiol 2020; 10:353. [PMID: 32923406 PMCID: PMC7456833 DOI: 10.3389/fcimb.2020.00353] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2020] [Accepted: 06/08/2020] [Indexed: 11/13/2022] Open
Abstract
Sphingosine 1-Phosphate (S1P) is a bioactive lipid intermediate in the sphingolipid metabolism, which exist in two pools, intracellular and extracellular, and each pool has a different function. The circulating extracellular pool, specifically the plasma S1P is shown to be important in regulating various physiological processes related to malaria pathogenesis in recent years. Although blood cells (red blood cells and platelets), vascular endothelial cells and hepatocytes are considered as the important sources of plasma S1P, their extent of contribution is still debated. The red blood cells (RBCs) and platelets serve as a major repository of intracellular S1P due to lack, or low activity of S1P degrading enzymes, however, contribution of platelets toward maintaining plasma S1P is shown negligible under normal condition. Substantial evidences suggest platelets loss during falciparum infection as a contributing factor for severe malaria. However, platelets function as a source for plasma S1P in malaria needs to be examined experimentally. RBC being the preferential site for parasite seclusion, and having the ability of trans-cellular S1P transportation to EC upon tight cell-cell contact, might play critical role in differential S1P distribution and parasite growth. In the present review, we have summarized the significance of both the S1P pools in the context of malaria, and how the RBC content of S1P can be channelized in better ways for its possible implication in therapeutic opportunities to control malaria.
Collapse
Affiliation(s)
| | - Shailja Singh
- Special Centre for Molecular Medicine, Jawaharlal Nehru University, New Delhi, India
| |
Collapse
|
13
|
Bush AM, Sandino CM, Ramachandran S, Ong F, Dwork N, Zucker EJ, Syed AB, Pauly JM, Alley MT, Vasanawala SS. Rosette Trajectories Enable Ungated, Motion-Robust, Simultaneous Cardiac and Liver T 2 * Iron Assessment. J Magn Reson Imaging 2020; 52:1688-1698. [PMID: 32452088 DOI: 10.1002/jmri.27196] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2020] [Revised: 04/30/2020] [Accepted: 05/01/2020] [Indexed: 11/06/2022] Open
Abstract
BACKGROUND Quantitative T2 * MRI is the standard of care for the assessment of iron overload. However, patient motion corrupts T2 * estimates. PURPOSE To develop and evaluate a motion-robust, simultaneous cardiac and liver T2 * imaging approach using non-Cartesian, rosette sampling and a model-based reconstruction as compared to clinical-standard Cartesian MRI. STUDY TYPE Prospective. PHANTOM/POPULATION Six ferumoxytol-containing phantoms (26-288 μg/mL). Eight healthy subjects and 18 patients referred for clinically indicated iron overload assessment. FIELD STRENGTH/SEQUENCE 1.5T, 2D Cartesian and rosette gradient echo (GRE) ASSESSMENT: GRE T2 * values were validated in ferumoxytol phantoms. In healthy subjects, test-retest and spatial coefficient of variation (CoV) analysis was performed during three breathing conditions. Cartesian and rosette T2 * were compared using correlation and Bland-Altman analysis. Images were rated by three experienced radiologists on a 5-point scale. STATISTICAL TESTS Linear regression, analysis of variance (ANOVA), and paired Student's t-testing were used to compare reproducibility and variability metrics in Cartesian and rosette scans. The Wilcoxon rank test was used to assess reader score comparisons and reader reliability was measured using intraclass correlation analysis. RESULTS Rosette R2* (1/T2 *) was linearly correlated with ferumoxytol concentration (r2 = 1.00) and not significantly different than Cartesian values (P = 0.16). During breath-holding, ungated rosette liver and heart T2 * had lower spatial CoV (liver: 18.4 ± 9.3% Cartesian, 8.8% ± 3.4% rosette, P = 0.02, heart: 37.7% ± 14.3% Cartesian, 13.4% ± 1.7% rosette, P = 0.001) and higher-quality scores (liver: 3.3 [3.0-3.6] Cartesian, 4.7 [4.1-4.9] rosette, P = 0.005, heart: 3.0 [2.3-3] Cartesian, 4.5 [3.8-5.0] rosette, P = 0.005) compared to Cartesian values. During free-breathing and failed breath-holding, Cartesian images had very poor to average image quality with significant artifacts, whereas rosette remained very good, with minimal artifacts (P = 0.001). DATA CONCLUSION Rosette k-sampling with a model-based reconstruction offers a clinically useful motion-robust T2 * mapping approach for iron quantification. J. MAGN. RESON. IMAGING 2020;52:1688-1698.
Collapse
Affiliation(s)
- Adam M Bush
- Department of Radiology, Stanford University, Palo Alto, California, USA
| | - Christopher M Sandino
- Department of Electrical Engineering, Stanford University, Palo Alto, California, USA
| | - Shreya Ramachandran
- Department of Electrical Engineering and Computer Science, University of California, Berkeley, California, USA
| | - Frank Ong
- Department of Radiology, Stanford University, Palo Alto, California, USA
| | - Nicholas Dwork
- Department of Radiology and Biomedical Imaging, University of California, San Francisco, California, USA
| | - Evan J Zucker
- Department of Radiology, Stanford University, Palo Alto, California, USA
| | - Ali B Syed
- Department of Radiology, Stanford University, Palo Alto, California, USA
| | - John M Pauly
- Department of Electrical Engineering, Stanford University, Palo Alto, California, USA
| | - Marcus T Alley
- Department of Radiology, Stanford University, Palo Alto, California, USA
| | | |
Collapse
|
14
|
Lee WC, Russell B, Sobota RM, Ghaffar K, Howland SW, Wong ZX, Maier AG, Dorin-Semblat D, Biswas S, Gamain B, Lau YL, Malleret B, Chu C, Nosten F, Renia L. Plasmodium-infected erythrocytes induce secretion of IGFBP7 to form type II rosettes and escape phagocytosis. eLife 2020; 9:e51546. [PMID: 32066522 PMCID: PMC7048393 DOI: 10.7554/elife.51546] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2019] [Accepted: 01/27/2020] [Indexed: 12/21/2022] Open
Abstract
In malaria, rosetting is described as a phenomenon where an infected erythrocyte (IRBC) is attached to uninfected erythrocytes (URBC). In some studies, rosetting has been associated with malaria pathogenesis. Here, we have identified a new type of rosetting. Using a step-by-step approach, we identified IGFBP7, a protein secreted by monocytes in response to parasite stimulation, as a rosette-stimulator for Plasmodium falciparum- and P. vivax-IRBC. IGFBP7-mediated rosette-stimulation was rapid yet reversible. Unlike type I rosetting that involves direct interaction of rosetting ligands on IRBC and receptors on URBC, the IGFBP7-mediated, type II rosetting requires two additional serum factors, namely von Willebrand factor and thrombospondin-1. These two factors interact with IGFBP7 to mediate rosette formation by the IRBC. Importantly, the IGFBP7-induced type II rosetting hampers phagocytosis of IRBC by host phagocytes.
Collapse
Affiliation(s)
- Wenn-Chyau Lee
- Singapore Immunology Network (SIgN)Agency for Science, Technology and Research (A*STAR)SingaporeSingapore
| | - Bruce Russell
- Department of Microbiology and ImmunologyUniversity of OtagoDunedinNew Zealand
| | - Radoslaw Mikolaj Sobota
- Systems Structural Biology Group, Institute of Molecular and Cell Biology (IMCB)Agency for Science, Technology and Research (A*STAR)SingaporeSingapore
- Institute of Medical Biology (IMB) Agency for Science, Technology and Research (A*STAR)SingaporeSingapore
| | - Khairunnisa Ghaffar
- Singapore Immunology Network (SIgN)Agency for Science, Technology and Research (A*STAR)SingaporeSingapore
| | - Shanshan W Howland
- Singapore Immunology Network (SIgN)Agency for Science, Technology and Research (A*STAR)SingaporeSingapore
| | - Zi Xin Wong
- Singapore Immunology Network (SIgN)Agency for Science, Technology and Research (A*STAR)SingaporeSingapore
| | - Alexander G Maier
- Biomedical Sciences and Biochemistry, Research School of BiologyAustralian National UniversityCanberraAustralia
| | - Dominique Dorin-Semblat
- Université de Paris, Biologie Intégrée du Globule Rouge, UMR_S1134, BIGR, INSERMParisFrance
- Institut National de la Transfusion SanguineParisFrance
| | - Subhra Biswas
- Singapore Immunology Network (SIgN)Agency for Science, Technology and Research (A*STAR)SingaporeSingapore
| | - Benoit Gamain
- Université de Paris, Biologie Intégrée du Globule Rouge, UMR_S1134, BIGR, INSERMParisFrance
- Institut National de la Transfusion SanguineParisFrance
| | - Yee-Ling Lau
- Department of ParasitologyFaculty of Medicine, University of MalayaKuala LumpurMalaysia
| | - Benoit Malleret
- Singapore Immunology Network (SIgN)Agency for Science, Technology and Research (A*STAR)SingaporeSingapore
- Department of Microbiology and Immunology, Yong Loo Lin School of MedicineNational University of SingaporeSingaporeSingapore
| | - Cindy Chu
- Shoklo Malaria Research Unit, Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical MedicineMahidol UniversityMae SotThailand
- Centre for Tropical Medicine, Nuffield Department of MedicineUniversity of OxfordOxfordUnited Kingdom
| | - François Nosten
- Shoklo Malaria Research Unit, Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical MedicineMahidol UniversityMae SotThailand
- Centre for Tropical Medicine, Nuffield Department of MedicineUniversity of OxfordOxfordUnited Kingdom
| | - Laurent Renia
- Singapore Immunology Network (SIgN)Agency for Science, Technology and Research (A*STAR)SingaporeSingapore
| |
Collapse
|
15
|
Miller AD, Koehler JW, Donovan TA, Stewart JE, Porter BF, Rissi DR, Priestnall SL, Schulman FY. Canine Ependymoma: Diagnostic Criteria and Common Pitfalls. Vet Pathol 2019; 56:860-867. [PMID: 31266414 DOI: 10.1177/0300985819859872] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Reports of canine ependymoma are generally restricted to single case reports with tumor incidence estimated at 2% to 3% of primary central nervous system (CNS) tumors. While most commonly reported in the lateral ventricle, tumors can occur anywhere in the ventricular system and in extraventricular locations. Rosettes and pseudorosettes are a common histologic feature; however, these features can be mimicked by other CNS neoplasms. Thirty-seven potential ependymoma cases were identified in a retrospective database search of 8 institutions, and a histologic review of all cases was conducted. Of 37 cases, 22 candidate cases were further subjected to a consensus histologic and immunohistochemical review, and only 5 of 37 (13.5%) were conclusively identified as ependymoma. The neuroanatomic locations were the lateral ventricle (3/5), third ventricle (1/5), and mesencephalic aqueduct (1/5). Subtypes were papillary (4/5) and tanycytic (1/5). Histologic features included rosettes (5/5), pseudorosettes (5/5), ependymal canals (2/5), tanycytic differentiation (1/5), blepharoplasts (1/5), ciliated cells (1/5), and high nuclear to cytoplasmic ratio (5/5). Immunolabeling for GFAP (4/4) and CKAE1/3 (3/4) was found in pseudorosettes, rosettes, and scattered individual neoplastic cells. Diffuse but variably intense cytoplasmic S100 immunolabeling was detected in 3 of 4 cases. Olig2 intranuclear immunolabeling was observed in less than 1% of the neoplastic cells (3/3). Tumors that had pseudorosettes and mimicked ependymoma included oligodendroglioma, choroid plexus tumor, pituitary corticotroph adenoma, papillary meningioma, and suprasellar germ cell tumor. These findings indicate that canine ependymoma is an extremely rare neoplasm with histomorphologic features that overlap with other primary CNS neoplasms.
Collapse
Affiliation(s)
- Andrew D Miller
- Department of Biomedical Sciences, Section of Anatomic Pathology, Cornell University College of Veterinary Medicine, Ithaca, NY, USA
| | - Jennifer W Koehler
- Department of Pathobiology, Auburn University, College of Veterinary Medicine, Auburn, AL, USA
| | - Taryn A Donovan
- Department of Anatomic Pathology, The Animal Medical Center, New York, NY, USA
| | | | - Brian F Porter
- Department of Veterinary Pathobiology, Texas A&M University, College Station, TX, USA
| | - Daniel R Rissi
- Athens Veterinary Diagnostic Laboratory and Department of Pathology, University of Georgia, College of Veterinary Medicine, Athens, GA, USA
| | - Simon L Priestnall
- Department of Pathobiology and Population Sciences, The Royal Veterinary College, Hatfield, UK
| | | |
Collapse
|
16
|
Felföldi T, Márton Z, Szabó A, Mentes A, Bóka K, Márialigeti K, Máthé I, Koncz M, Schumann P, Tóth E. Siculibacillus lacustris gen. nov., sp. nov., a new rosette-forming bacterium isolated from a freshwater crater lake (Lake St. Ana, Romania). Int J Syst Evol Microbiol 2019; 69:1731-1736. [PMID: 30950779 DOI: 10.1099/ijsem.0.003385] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
A new aerobic alphaproteobacterium, strain SA-279T, was isolated from a water sample of a crater lake. The 16S rRNA gene sequence analysis revealed that strain SA-279T formed a distinct lineage within the family Ancalomicrobiaceae and shared the highest pairwise similarity values with Pinisolibacterravus E9T (96.4 %) and Ancalomicrobiumadetum NBRC 102456T (94.2 %). Cells of strain SA-279T were rod-shaped, motile, oxidase and catalase positive, and capable of forming rosettes. Its predominant fatty acids were C18 : 1ω7c (69.0 %) and C16 : 1ω7c (22.7 %), the major respiratory quinone was Q-10, and the main polar lipids were phosphatidylethanolamine, phosphatidylmonomethylethanolamine, phosphatidylcholine, phosphatidylglycerol, an unidentified aminophospholipid and an unidentified lipid. The G+C content of the genomic DNA of strain SA-279T was 69.2 mol%. On the basis of the phenotypic, chemotaxonomic and molecular data, strain SA-279T is considered to represent a new genus and species within the family Ancalomicrobiaceae, for which the name Siculibacillus lacustris gen. nov., sp. nov. is proposed. The type strain is SA-279T (=DSM 29840T=JCM 31761T).
Collapse
Affiliation(s)
- Tamás Felföldi
- 2Department of Bioengineering, Sapientia Hungarian University of Transylvania, Piaţa Libertăţii 1, 530104 Miercurea Ciuc, Romania.,1Department of Microbiology, ELTE Eötvös Loránd University, Pázmány Péter stny. 1/c, 1117 Budapest, Hungary
| | - Zsuzsanna Márton
- 1Department of Microbiology, ELTE Eötvös Loránd University, Pázmány Péter stny. 1/c, 1117 Budapest, Hungary
| | - Attila Szabó
- 1Department of Microbiology, ELTE Eötvös Loránd University, Pázmány Péter stny. 1/c, 1117 Budapest, Hungary
| | - Anikó Mentes
- 1Department of Microbiology, ELTE Eötvös Loránd University, Pázmány Péter stny. 1/c, 1117 Budapest, Hungary
| | - Károly Bóka
- 3Department of Plant Anatomy, ELTE Eötvös Loránd University, Pázmány Péter stny. 1/c, 1117 Budapest, Hungary
| | - Károly Márialigeti
- 1Department of Microbiology, ELTE Eötvös Loránd University, Pázmány Péter stny. 1/c, 1117 Budapest, Hungary
| | - István Máthé
- 2Department of Bioengineering, Sapientia Hungarian University of Transylvania, Piaţa Libertăţii 1, 530104 Miercurea Ciuc, Romania
| | - Mihály Koncz
- 2Department of Bioengineering, Sapientia Hungarian University of Transylvania, Piaţa Libertăţii 1, 530104 Miercurea Ciuc, Romania.,†Present address: Institute of Biochemistry, Biological Research Centre of the Hungarian Academy of Sciences, Temesvári krt. 62, 6726 Szeged, Hungary
| | - Peter Schumann
- 4Leibniz Institute DSMZ - German Collection of Microorganisms and Cell Cultures, Inhoffenstraße 7B, 38124 Braunschweig, Germany
| | - Erika Tóth
- 1Department of Microbiology, ELTE Eötvös Loránd University, Pázmány Péter stny. 1/c, 1117 Budapest, Hungary
| |
Collapse
|
17
|
Scholes DR, Wszalek AE, Paige KN. Regrowth patterns and rosette attributes contribute to the differential compensatory responses of Arabidopsis thaliana genotypes to apical damage. Plant Biol (Stuttg) 2016; 18:239-48. [PMID: 26434737 DOI: 10.1111/plb.12404] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/05/2015] [Accepted: 09/27/2015] [Indexed: 05/09/2023]
Abstract
A plant's compensatory performance refers to its ability to maintain or increase its reproductive output following damage. The ability of a plant to compensate depends on numerous factors including the type, severity, frequency and timing of damage, the environmental conditions and the plant's genotype. Upon apical damage, a cascade of hormonal and genetic responses often produces dramatic changes in a plant's growth, development, architecture and physiology. All else being equal, this response is largely dependent on a plant's genotype, with different regrowth patterns displayed by different genotypes of a given species. In this study, we compare the architectural and growth patterns of two Arabidopsis thaliana genotypes following apical damage. Specifically, we characterise regrowth patterns of the genotypes Columbia-4 and Landsberg erecta, which typically differ in their compensation to apical meristem removal. We report that Landsberg erecta suffered reductions in the number of stems produced, maximum elongation rate, a delay in reaching this rate, lower average rosette quality throughout the growing period, and ultimately, less aboveground dry biomass and seed production when damaged compared to undamaged control plants. Columbia-4 had no reductions in any of these measures and maintained larger rosette area when clipped relative to when unclipped. Based on the apparent influence of the rosette on these genotypes' compensatory performances, we performed a rosette removal experiment, which confirmed that the rosette contributes to compensatory performance. This study provides a novel characterisation of regrowth patterns following apical damage, with insights into those measures having the largest effect on plant performance.
Collapse
Affiliation(s)
- D R Scholes
- Department of Biology, University of Indianapolis, Indianapolis, IN, USA
- School of Integrative Biology, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - A E Wszalek
- School of Integrative Biology, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - K N Paige
- School of Integrative Biology, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| |
Collapse
|
18
|
Abstract
The vascular basement membrane (BM) is a thin and dense cross-linked extracellular matrix layer that covers and protects blood vessels. Understanding how cells cross the physical barrier of the vascular BM will provide greater insight into the potentially critical role of vascular BM breaching in cancer extravasation, leukocyte trafficking and angiogenic sprouting. In the last year, new evidence has mechanistically linked the breaching of vascular BM with the formation of specific cellular micro-domains known as podosomes and invadopodia. These structures are specialized cell-matrix contacts with an inherent ability to degrade the extracellular matrix. Specifically, the formation of podosomes or invadopodia was shown as an important step in vascular sprouting and tumor cell extravasation, respectively. Here, we review and comment on these recent findings and explore the functions of podosomes and invadopodia within the context of pathological processes such as tumor dissemination and tumor angiogenesis.
Collapse
Affiliation(s)
- Giorgio Seano
- a Laboratory of Cell Migration ; Candiolo Cancer Institute - FPO; IRCCS ; Turin , Italy
| | | |
Collapse
|
19
|
Sulhyan KR, Deshmukh BD, Gosavi AV, Ramteerthakar NA. Neuroblastoma-like schwannoma in a case of schwannomatosis: Report of a rare case. Int J Health Sci (Qassim) 2015; 9:478-481. [PMID: 26715928 PMCID: PMC4682603] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/05/2023] Open
Abstract
Schwannomatosis is a term used to describe patients with multiple nonvestibular schwannomas with no other stigmata of neurofibromatosis type-2 (NF2). Neuroblastoma-like schwannoma is a rare subtype of schwannoma, with histological features resembling a neuroblastoma. This case is probabaly the second case of very uncommon neuroblastoma-like schwannoma, in a patient of schwannomatosis.
Collapse
Affiliation(s)
- Kalpana R Sulhyan
- Department of Pathology, Government Medical College, Miraj, Maharashtra, India
| | - Bhakti D Deshmukh
- Department of Pathology, Government Medical College, Miraj, Maharashtra, India
| | - Alka V Gosavi
- Department of Pathology, Government Medical College, Miraj, Maharashtra, India
| | | |
Collapse
|
20
|
Dhondt S, Gonzalez N, Blomme J, De Milde L, Van Daele T, Van Akoleyen D, Storme V, Coppens F, T S Beemster G, Inzé D. High-resolution time-resolved imaging of in vitro Arabidopsis rosette growth. Plant J 2014; 80:172-84. [PMID: 25041085 DOI: 10.1111/tpj.12610] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/06/2014] [Revised: 06/24/2014] [Accepted: 07/02/2014] [Indexed: 05/20/2023]
Abstract
Although quantitative characterization of growth phenotypes is of key importance for the understanding of essential networks driving plant growth, the majority of growth-related genes are still being identified based on qualitative visual observations and/or single-endpoint quantitative measurements. We developed an in vitro growth imaging system (IGIS) to perform time-resolved analysis of rosette growth. In this system, Arabidopsis plants are grown in Petri dishes mounted on a rotating disk, and images of each plate are taken on an hourly basis. Automated image analysis was developed in order to obtain several growth-related parameters, such as projected rosette area, rosette relative growth rate, compactness and stockiness, over time. To illustrate the use of the platform and the resulting data, we present the results for the growth response of Col-0 plants subjected to three mild stress conditions. Although the reduction in rosette area was relatively similar at 19 days after stratification, the time-lapse analysis demonstrated that plants react differently to salt, osmotic and oxidative stress. The rosette area was altered at various time points during development, and leaf movement and shape parameters were also affected differently. We also used the IGIS to analyze in detail the growth behavior of mutants with enhanced leaf size. Analysis of several growth-related parameters over time in these mutants revealed several specificities in growth behavior, underlining the high complexity of leaf growth coordination. These results demonstrate that time-resolved imaging of in vitro rosette growth generates a better understanding of growth phenotypes than endpoint measurements.
Collapse
Affiliation(s)
- Stijn Dhondt
- Department of Plant Systems Biology, Vlaams Instituut voor Biotechnologie, Technologiepark 927, 9052, Gent, Belgium; Department of Plant Biotechnology and Bioinformatics, Ghent University, Technologiepark 927, 9052, Gent, Belgium
| | | | | | | | | | | | | | | | | | | |
Collapse
|
21
|
Genové G, Mollick T, Johansson K. Photoreceptor degeneration, structural remodeling and glial activation: a morphological study on a genetic mouse model for pericyte deficiency. Neuroscience 2014; 279:269-84. [PMID: 25224828 DOI: 10.1016/j.neuroscience.2014.09.013] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2014] [Revised: 09/01/2014] [Accepted: 09/05/2014] [Indexed: 01/10/2023]
Abstract
Interaction between pericytes and endothelial cells via platelet-derived growth factor B (PDGF-B) signaling is critical for the development of the retinal microvasculature. The PDGF-B retention motif controls the spatial distribution range of the growth factor in the vicinity of its producing endothelial cells allowing its recognition by PDGF receptor beta-(PDGFR-β)-carrying pericytes; this promotes recruitment of pericytes to the vascular basement membrane. Impairment of the PDGF-B signaling mechanism causes development of vascular abnormalities, and in the retina this consequently leads to defects in the neurological circuitry. The vascular pathology in the pdgf-b(ret/ret) (PDGF-B retention motif knockout) mouse retina has been previously reported; our study investigates the progressive neuronal defects and changes in the retinal morphology of this pericyte-deficient mouse model. Immunohistochemical analysis revealed retinal injuries to occur as early as postnatal day (P) 10 with substantial damage progressing from P15 and onward. Vascular abnormalities were apparent from P10, however, prominent neuronal defects were mostly observed from P15, beginning with the compromised integrity of the laminated retinal structure characterized by the presence of rosettes and focally distorted regions. Photoreceptor degeneration was observed by loss of both rod and cone cells, including the disassembly and altered structure of their synaptic terminals. Significant shortening of cone outer segments was observed from P10 and later stages; however, decrease in cone density was only observed at P28. Disorganization and dendrite remodeling of rod bipolar cells also added to the diminished neural and synaptic integrity. Moreover, in response to retinal injuries, Müller and microglial cells were observed to be in the reactive phenotype from P15 and onward. Such a sequence of events indicates that the pdgf-b(ret/ret) mouse model displays a short time frame between P10 and P15, during which the retina shifts to a retinopathic phase by the development of prominently altered morphological features.
Collapse
Affiliation(s)
- G Genové
- Division of Vascular Biology, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
| | - T Mollick
- School of Health and Medicine, Örebro University, Örebro, Sweden
| | - K Johansson
- School of Health and Medicine, Örebro University, Örebro, Sweden.
| |
Collapse
|
22
|
Abstract
BACKGROUND Spitz nevi demonstrate a diverse spectrum of morphologies. Recently, there have been two reported examples of Spitz nevi with rosette-like structures similar to Homer-Wright rosettes. Rosettes have also been described in melanomas and in a proliferative nodule arising in a congenital nevus. METHODS A retrospective review of 104 cases of Spitz nevi and variants (n = 51), pigmented spindle cell nevi (n = 26), combined melanocytic nevi with features of Spitz (n = 8), atypical Spitz tumor (AST, n = 9), and spitzoid melanoma (n = 10). RESULTS Rosette-like structures were present in 3 of the 104 cases (2.9%), including a compound Spitz nevus, a desmoplastic Spitz nevus, and an AST. All three cases demonstrated several foci of small nests of epithelioid cells with peripherally palisaded nuclei arranged around a central area of fibrillar eosinophilic cytoplasm. Immunohistochemical staining of the three spitzoid lesions demonstrated that the rosette-like structures express S100 protein, Melan-A, and neuron specific enolase (NSE) and lacked expression of neurofilament, glial fibrillary acidic protein and synaptophysin. CONCLUSIONS While uncommon, rosette-like structures can occur as a focal feature in Spitz nevi and AST. Rosette-like structures may represent a normal morphologic finding in Spitz nevi, and awareness of them may prevent misdiagnosis as a neural tumor or melanoma.
Collapse
Affiliation(s)
- David P Arps
- Department of Pathology, University of Michigan, Ann Arbor, MI 48109, USA
| | | | | | | |
Collapse
|