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Rodríguez-Martín M, Báez-Flores J, Ribes V, Isidoro-García M, Lacal J, Prieto-Matos P. Non-Mammalian Models for Understanding Neurological Defects in RASopathies. Biomedicines 2024; 12:841. [PMID: 38672195 PMCID: PMC11048513 DOI: 10.3390/biomedicines12040841] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2024] [Revised: 03/27/2024] [Accepted: 04/08/2024] [Indexed: 04/28/2024] Open
Abstract
RASopathies, a group of neurodevelopmental congenital disorders stemming from mutations in the RAS/MAPK pathway, present a unique opportunity to delve into the intricacies of complex neurological disorders. Afflicting approximately one in a thousand newborns, RASopathies manifest as abnormalities across multiple organ systems, with a pronounced impact on the central and peripheral nervous system. In the pursuit of understanding RASopathies' neurobiology and establishing phenotype-genotype relationships, in vivo non-mammalian models have emerged as indispensable tools. Species such as Danio rerio, Drosophila melanogaster, Caenorhabditis elegans, Xenopus species and Gallus gallus embryos have proven to be invaluable in shedding light on the intricate pathways implicated in RASopathies. Despite some inherent weaknesses, these genetic models offer distinct advantages over traditional rodent models, providing a holistic perspective on complex genetics, multi-organ involvement, and the interplay among various pathway components, offering insights into the pathophysiological aspects of mutations-driven symptoms. This review underscores the value of investigating the genetic basis of RASopathies for unraveling the underlying mechanisms contributing to broader neurological complexities. It also emphasizes the pivotal role of non-mammalian models in serving as a crucial preliminary step for the development of innovative therapeutic strategies.
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Affiliation(s)
- Mario Rodríguez-Martín
- Laboratory of Functional Genetics of Rare Diseases, Department of Microbiology and Genetics, University of Salamanca, 37007 Salamanca, Spain; (M.R.-M.); (J.B.-F.)
- Institute of Biomedical Research of Salamanca (IBSAL), 37007 Salamanca, Spain; (M.I.-G.); (P.P.-M.)
| | - Juan Báez-Flores
- Laboratory of Functional Genetics of Rare Diseases, Department of Microbiology and Genetics, University of Salamanca, 37007 Salamanca, Spain; (M.R.-M.); (J.B.-F.)
- Institute of Biomedical Research of Salamanca (IBSAL), 37007 Salamanca, Spain; (M.I.-G.); (P.P.-M.)
| | - Vanessa Ribes
- Institut Jacques Monod, Université Paris Cité, CNRS, F-75013 Paris, France;
| | - María Isidoro-García
- Institute of Biomedical Research of Salamanca (IBSAL), 37007 Salamanca, Spain; (M.I.-G.); (P.P.-M.)
- Clinical Biochemistry Department, Hospital Universitario de Salamanca, 37007 Salamanca, Spain
- Clinical Rare Diseases Reference Unit DiERCyL, 37007 Castilla y León, Spain
- Department of Medicine, University of Salamanca, 37007 Salamanca, Spain
| | - Jesus Lacal
- Laboratory of Functional Genetics of Rare Diseases, Department of Microbiology and Genetics, University of Salamanca, 37007 Salamanca, Spain; (M.R.-M.); (J.B.-F.)
- Institute of Biomedical Research of Salamanca (IBSAL), 37007 Salamanca, Spain; (M.I.-G.); (P.P.-M.)
| | - Pablo Prieto-Matos
- Institute of Biomedical Research of Salamanca (IBSAL), 37007 Salamanca, Spain; (M.I.-G.); (P.P.-M.)
- Clinical Rare Diseases Reference Unit DiERCyL, 37007 Castilla y León, Spain
- Department of Pediatrics, Hospital Universitario de Salamanca, 37007 Salamanca, Spain
- Department of Biomedical and Diagnostics Science, University of Salamanca, 37007 Salamanca, Spain
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Rufaihah AJ, Chen CK, Yap CH, Mattar CNZ. Mending a broken heart: In vitro, in vivo and in silico models of congenital heart disease. Dis Model Mech 2021; 14:dmm047522. [PMID: 33787508 PMCID: PMC8033415 DOI: 10.1242/dmm.047522] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Birth defects contribute to ∼0.3% of global infant mortality in the first month of life, and congenital heart disease (CHD) is the most common birth defect among newborns worldwide. Despite the significant impact on human health, most treatments available for this heterogenous group of disorders are palliative at best. For this reason, the complex process of cardiogenesis, governed by multiple interlinked and dose-dependent pathways, is well investigated. Tissue, animal and, more recently, computerized models of the developing heart have facilitated important discoveries that are helping us to understand the genetic, epigenetic and mechanobiological contributors to CHD aetiology. In this Review, we discuss the strengths and limitations of different models of normal and abnormal cardiogenesis, ranging from single-cell systems and 3D cardiac organoids, to small and large animals and organ-level computational models. These investigative tools have revealed a diversity of pathogenic mechanisms that contribute to CHD, including genetic pathways, epigenetic regulators and shear wall stresses, paving the way for new strategies for screening and non-surgical treatment of CHD. As we discuss in this Review, one of the most-valuable advances in recent years has been the creation of highly personalized platforms with which to study individual diseases in clinically relevant settings.
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Affiliation(s)
- Abdul Jalil Rufaihah
- Healthy Longevity Translational Research Programme, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 119228
| | - Ching Kit Chen
- Department of Surgery, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 119228
- Department of Paediatrics, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 119228
| | - Choon Hwai Yap
- Division of Cardiology, Department of Paediatrics, Khoo Teck Puat -National University Children's Medical Institute, National University Health System, Singapore 119228
- Department of Bioengineering, Imperial College London, London, UK
| | - Citra N Z Mattar
- Experimental Fetal Medicine Group, Department of Obstetrics and Gynaecology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 119228
- Department of Obstetrics and Gynaecology, National University Health System, Singapore 119228
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Abstract
The chick embryo is a powerful model for experimental embryology due to its accessibility, sturdiness, and ease of manipulation. Here we describe protocols for analysis of protein-DNA and protein-protein interactions in tissues and cells isolated from the developing chick. These assays are aimed at the identification of interactions between transcription factors and regulatory elements in the genome, and, in combination with functional assays, can be used for the delineation of gene regulatory circuits.
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Vermillion KL, Lidberg KA, Gammill LS. Expression of actin-binding proteins and requirement for actin-depolymerizing factor in chick neural crest cells. Dev Dyn 2014; 243:730-8. [PMID: 24868596 DOI: 10.1002/dvdy.24105] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
BACKGROUND Neural crest cells are multipotent cells that migrate extensively throughout vertebrate embryos to form diverse lineages. Cell migration requires polarized, organized actin networks that provide the driving force for motility. Actin-binding proteins that regulate neural crest cell migration are just beginning to be defined. RESULTS We recently identified a number of actin-associated factors through proteomic profiling of methylated proteins in migratory neural crest cells. Here, we report the previously undocumented expression pattern of three of these proteins in chick early neural crest development: doublecortin (DCX), tropomyosin-1 (TPM-1), and actin depolymerizing factor (ADF). All three genes are expressed with varying degrees of specificity and intensity in premigratory and migratory neural crest cells, and their resulting proteins exhibit distinct subcellular localization in migratory neural crest cells. Morpholino knock down of ADF reveals it is required for Sox10 gene expression, but minimally important during neural crest migration. CONCLUSIONS Neural crest cells express DCX, TPM-1, and ADF. ADF is necessary during neural crest specification, but largely dispensable for migration.
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Jacques-Fricke BT, Gammill LS. Neural crest specification and migration independently require NSD3-related lysine methyltransferase activity. Mol Biol Cell 2014; 25:4174-86. [PMID: 25318671 PMCID: PMC4263458 DOI: 10.1091/mbc.e13-12-0744] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Nuclear receptor–binding, SET-domain containing 3 (NSD3) is the first protein methyltransferase essential for early neural crest development. NSD3 is required for neural crest gene expression but not for H3K36 dimethylation of most neural crest genes. NSD3-related methyltransferase activity independently regulates neural crest migration. Neural crest precursors express genes that cause them to become migratory, multipotent cells, distinguishing them from adjacent stationary neural progenitors in the neurepithelium. Histone methylation spatiotemporally regulates neural crest gene expression; however, the protein methyltransferases active in neural crest precursors are unknown. Moreover, the regulation of methylation during the dynamic process of neural crest migration is unclear. Here we show that the lysine methyltransferase NSD3 is abundantly and specifically expressed in premigratory and migratory neural crest cells. NSD3 expression commences before up-regulation of neural crest genes, and NSD3 is necessary for expression of the neural plate border gene Msx1, as well as the key neural crest transcription factors Sox10, Snail2, Sox9, and FoxD3, but not gene expression generally. Nevertheless, only Sox10 histone H3 lysine 36 dimethylation requires NSD3, revealing unexpected complexity in NSD3-dependent neural crest gene regulation. In addition, by temporally limiting expression of a dominant negative to migratory stages, we identify a novel, direct requirement for NSD3-related methyltransferase activity in neural crest migration. These results identify NSD3 as the first protein methyltransferase essential for neural crest gene expression during specification and show that NSD3-related methyltransferase activity independently regulates migration.
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Affiliation(s)
- Bridget T Jacques-Fricke
- Department of Genetics, Cell Biology, and Development, University of Minnesota, Minneapolis, MN 55455
| | - Laura S Gammill
- Department of Genetics, Cell Biology, and Development, University of Minnesota, Minneapolis, MN 55455
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Fairchild CL, Conway JP, Schiffmacher AT, Taneyhill LA, Gammill LS. FoxD3 regulates cranial neural crest EMT via downregulation of tetraspanin18 independent of its functions during neural crest formation. Mech Dev 2014; 132:1-12. [PMID: 24582980 PMCID: PMC4001935 DOI: 10.1016/j.mod.2014.02.004] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2013] [Revised: 01/20/2014] [Accepted: 02/19/2014] [Indexed: 01/09/2023]
Abstract
The scaffolding protein tetraspanin18 (Tspan18) maintains epithelial cadherin-6B (Cad6B) to antagonize chick cranial neural crest epithelial-to-mesenchymal transition (EMT). For migration to take place, Tspan18 must be downregulated. Here, we characterize the role of the winged-helix transcription factor FoxD3 in the control of Tspan18 expression. Although we previously found that Tspan18 mRNA persists several hours past the stage it would normally be downregulated in FoxD3-deficient neural folds, we now show that Tspan18 expression eventually declines. This indicates that while FoxD3 is crucial for initial downregulation of Tspan18, other factors subsequently impact Tspan18 expression. Remarkably, the classical EMT transcription factor Snail2 is not one of these factors. As in other vertebrates, FoxD3 is required for chick cranial neural crest specification and migration, however, FoxD3 has surprisingly little impact on chick cranial neural crest cell survival. Strikingly, Tspan18 knockdown rescues FoxD3-dependent neural crest migration defects, although neural crest specification is still deficient. This indicates that FoxD3 promotes cranial neural crest EMT by eliciting Tspan18 downregulation separable from its Tspan18-independent activity during neural crest specification and survival.
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Affiliation(s)
- Corinne L Fairchild
- Department of Genetics, Cell Biology, and Development, 6-160 Jackson Hall, 321 Church St. SE, University of Minnesota, Minneapolis, MN 55455, USA
| | - Joseph P Conway
- Department of Genetics, Cell Biology, and Development, 6-160 Jackson Hall, 321 Church St. SE, University of Minnesota, Minneapolis, MN 55455, USA
| | - Andrew T Schiffmacher
- Department of Animal and Avian Sciences, 1405 Animal Sciences Center, University of Maryland, College Park, MD 20742, USA
| | - Lisa A Taneyhill
- Department of Animal and Avian Sciences, 1405 Animal Sciences Center, University of Maryland, College Park, MD 20742, USA
| | - Laura S Gammill
- Department of Genetics, Cell Biology, and Development, 6-160 Jackson Hall, 321 Church St. SE, University of Minnesota, Minneapolis, MN 55455, USA.
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Kulesa PM, McKinney MC, McLennan R. Developmental imaging: the avian embryo hatches to the challenge. ACTA ACUST UNITED AC 2014; 99:121-33. [PMID: 23897596 DOI: 10.1002/bdrc.21036] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2013] [Accepted: 05/31/2013] [Indexed: 01/27/2023]
Abstract
The avian embryo provides a multifaceted model to study developmental mechanisms because of its accessibility to microsurgery, fluorescence cell labeling, in vivo imaging, and molecular manipulation. Early two-dimensional planar growth of the avian embryo mimics human development and provides unique access to complex cell migration patterns using light microscopy. Later developmental events continue to permit access to both light and other imaging modalities, making the avian embryo an excellent model for developmental imaging. For example, significant insights into cell and tissue behaviors within the primitive streak, craniofacial region, and cardiovascular and peripheral nervous systems have come from avian embryo studies. In this review, we provide an update to recent advances in embryo and tissue slice culture and imaging, fluorescence cell labeling, and gene profiling. We focus on how technical advances in the chick and quail provide a clearer understanding of how embryonic cell dynamics are beautifully choreographed in space and time to sculpt cells into functioning structures. We summarize how these technical advances help us to better understand basic developmental mechanisms that may lead to clinical research into human birth defects and tissue repair.
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Affiliation(s)
- Paul M Kulesa
- Stowers Institute for Medical Research, Kansas City, MO 64110, USA.
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Vermillion KL, Lidberg KA, Gammill LS. Cytoplasmic protein methylation is essential for neural crest migration. ACTA ACUST UNITED AC 2013; 204:95-109. [PMID: 24379414 PMCID: PMC3882789 DOI: 10.1083/jcb.201306071] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Post-translational methylation of the non-histone, actin-binding protein EF1α1 is essential for neural crest migration. As they initiate migration in vertebrate embryos, neural crest cells are enriched for methylation cycle enzymes, including S-adenosylhomocysteine hydrolase (SAHH), the only known enzyme to hydrolyze the feedback inhibitor of trans-methylation reactions. The importance of methylation in neural crest migration is unknown. Here, we show that SAHH is required for emigration of polarized neural crest cells, indicating that methylation is essential for neural crest migration. Although nuclear histone methylation regulates neural crest gene expression, SAHH and lysine-methylated proteins are abundant in the cytoplasm of migratory neural crest cells. Proteomic profiling of cytoplasmic, lysine-methylated proteins from migratory neural crest cells identified 182 proteins, several of which are cytoskeleton related. A methylation-resistant form of one of these proteins, the actin-binding protein elongation factor 1 alpha 1 (EF1α1), blocks neural crest migration. Altogether, these data reveal a novel and essential role for post-translational nonhistone protein methylation during neural crest migration and define a previously unknown requirement for EF1α1 methylation in migration.
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Affiliation(s)
- Katie L Vermillion
- Department of Genetics, Cell Biology, and Development, University of Minnesota, Minneapolis, MN 55455
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Spurlin J, Lwigale P. A technique to increase accessibility to late-stage chick embryos for in ovo manipulations. Dev Dyn 2013. [PMID: 23184557 DOI: 10.1002/dvdy.23907] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
BACKGROUND During early development, avian embryos are easily accessible in ovo for transplantations and experimental perturbations. However, these qualities of the avian embryonic model rapidly wane shortly after embryonic day (E)4 when the embryo is obscured by extraembryonic membranes, making it difficult to study developmental events that occur at later stages in vivo. RESULTS In this study, we describe a multistep method that involves initially windowing eggs at E3, followed by dissecting away extraembryonic membranes at E5 to facilitate embryo accessibility in ovo until later stages of development. The majority of the embryos subjected to this technique remain exposed between E5 and E8, then become gradually displaced by the growing allantois from posterior to anterior regions. CONCLUSIONS Exposed embryos are viable and compatible with embryological and modern developmental biology techniques including tissue grafting and ablation, gene manipulation by electroporation, and protein expression. This technique opens up new avenues for studying complex cellular interactions during organogenesis and can be further extrapolated to regeneration and stem cell studies.
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Affiliation(s)
- James Spurlin
- Department of Biochemistry and Cell Biology, Rice University, Houston, TX 77025, USA
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Fairchild CL, Gammill LS. Tetraspanin18 is a FoxD3-responsive antagonist of cranial neural crest epithelial-to-mesenchymal transition that maintains cadherin-6B protein. J Cell Sci 2013; 126:1464-76. [PMID: 23418345 PMCID: PMC3644144 DOI: 10.1242/jcs.120915] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/14/2013] [Indexed: 01/06/2023] Open
Abstract
During epithelial-to-mesenchymal transition (EMT), tightly associated, polarized epithelial cells become individual mesenchymal cells capable of migrating. Here, we investigate the role of the transmembrane protein tetraspanin18 (Tspan18) in chick cranial neural crest EMT. Tspan18 mRNA is expressed in premigratory cranial neural crest cells, but is absent from actively migrating neural crest cells. Tspan18 knockdown leads to a concomitant loss of cadherin-6B (Cad6B) protein, whereas Cad6B protein persists when Tspan18 expression is extended. The temporal profile of Cad6B mRNA downregulation is unaffected in these embryos, which indicates that Tspan18 maintains Cad6B protein levels and reveals that Cad6B is regulated by post-translational mechanisms. Although downregulation of Tspan18 is necessary, it is not sufficient for neural crest migration: the timing of neural crest emigration, basal lamina breakdown and Cad7 upregulation proceed normally in Tspan18-deficient cells. This emphasizes the need for coordinated transcriptional and post-translational regulation of Cad6B during EMT and illustrates that Tspan18-antagonized remodeling of cell-cell adhesions is only one step in preparation for cranial neural crest migration. Unlike Cad6B, which is transcriptionally repressed by Snail2, Tspan18 expression is downstream of the winged-helix transcription factor FoxD3, providing a new transcriptional input into cranial neural crest EMT. Together, our data reveal post-translational regulation of Cad6B protein levels by Tspan18 that must be relieved by a FoxD3-dependent mechanism in order for cranial neural crest cells to migrate. These results offer new insight into the molecular mechanisms of cranial neural crest EMT and expand our understanding of tetraspanin function relevant to metastasis.
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Affiliation(s)
| | - Laura S. Gammill
- Department of Genetics, Cell Biology, and Development, 6-160 Jackson Hall, 321 Church Street SE, University of Minnesota, Minneapolis, MN 55455, USA
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Roffers-Agarwal J, Hutt KJ, Gammill LS. Paladin is an antiphosphatase that regulates neural crest cell formation and migration. Dev Biol 2012; 371:180-90. [PMID: 22926139 DOI: 10.1016/j.ydbio.2012.08.007] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2012] [Revised: 08/05/2012] [Accepted: 08/15/2012] [Indexed: 12/31/2022]
Abstract
Although a network of transcription factors that specifies neural crest identity in the ectoderm has been defined, expression of neural crest transcription factors does not guarantee eventual migration as a neural crest cell. While much work has gone into determining regulatory relationships within the transcription factor network, the ability of protein modifications like phosphorylation to modulate the function of neural crest regulatory factors and determine when and where they are active also has crucial implications. Paladin, which was previously classified as a phosphatase based on sequence similarity, is expressed in chick neural crest precursors and is maintained throughout their epithelial to mesenchymal transition and migration. Loss of Paladin delays the expression of transcription factors Snail2 and Sox10 in premigratory neural crest cells, but does not affect accumulation of FoxD3, Cad6B or RhoB, indicating that Paladin differentially modulates the expression of genes previously thought to be coregulated within the neural crest gene regulatory network. Both gain and loss of Paladin function result in disrupted neural crest migration, reinforcing the importance of precisely regulated phosphorylation for neural crest migration. Mutation of critical, catalytic cysteine residues within Paladin's predicted phosphatase active site motifs did not abolish the function of Paladin in the neural crest. Collectively, these data indicate that Paladin is an antiphosphatase that modulates the activity of specific neural crest regulatory factors during neural crest development. Our work identifies a novel regulator of phosphorylation status that provides an additional layer of regulation in the neural crest.
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Affiliation(s)
- Julaine Roffers-Agarwal
- Department of Genetics, Cell Biology and Development, 6-160 Jackson Hall, 321 Church Street SE, University of Minnesota, Minneapolis, MN 55455, USA
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Brown CY, Eom DS, Amarnath S, Agarwala S. A simple technique for early in vivo electroporation of E1 chick embryos. Dev Dyn 2012; 241:545-52. [PMID: 22274994 DOI: 10.1002/dvdy.23747] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/19/2012] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The amenability of the chick embryo to a variety of manipulations has made it an ideal experimental model organism for over 100 years. The ability to manipulate gene function via in ovo electroporations has further revolutionized its value as an experimental model in the last 15 years. Although in ovo electroporations are simple to conduct in embryos ≥ E2, in ovo electroporations at early E1 stages have proven to be technically challenging due to the tissue damage and embryonic lethality such electroporations produce. RESULTS AND CONCLUSIONS Here we report our success with in vivo microelectroporations of E1 embryos as young as Hamburger-Hamilton Stage 4 (HH4). We provide evidence that such electroporations can be varied in size and can be spatially targeted. They cause minimal disruption of tissue-size, 3-dimensional morphology, cell survival, proliferation, and cell-fate specification. Our paradigm is easily adapted to a variety of experimental conditions since it does not depend upon the presence of a lumen to enclose the DNA solution during electroporation. It is thus compatible with the in vivo examination of E1 morphogenetic events (e.g., neural tube closure) where preservation of 3-dimensional morphology is critical.
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Affiliation(s)
- Charmaine Y Brown
- Institute for Cell and Molecular Biology, University of Texas at Austin, Austin, Texas 78712, USA
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