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Epiblast morphogenesis before gastrulation

Guojun Sheng
2015 Developmental Biology  
Please cite this article as: Sheng, G., Epiblast morphogenesis before gastrulation. Dev.  ...  All amniote species, however, have an extraembryonic tissue organization that is evolutionarily conserved (Ferner and Mess, 2011; Sheng and Foley, 2012) and its genesis underlies key morphogenetic processes  ... 
doi:10.1016/j.ydbio.2014.10.003 pmid:25446532 fatcat:icht7d3sr5gftko4uihbx5ipa4

Vive la difference

Guojun Sheng
2010 Cell Adhesion & Migration  
Sheng 1, * guest editor, Special Focus: eMT 1 Laboratory for early embryogenesis; riKen Center for Developmental Biology; Kobe, Hyogo Japan *Correspondence to: Guojun Sheng; Email:  ...  pathological EMTs, the lessons we learn from their contextual complexity may prove to be equally valuable, and in the long run, this may help us understand phenotypic diversities reported in pathological EMTs. guojun  ... 
doi:10.4161/cam.4.3.12642 pmid:20954294 pmcid:PMC2958621 fatcat:b3wtldzfxbfjlp7phsaje6sr6m

Day-1 chick development

Guojun Sheng
2013 Developmental Dynamics  
asymmetric distribution of hypoblast islands, and molecular asymmetry is also readily detectable in both the epiblast and hypoblast cells (Peter, 1938; Spratt and Haas, 1960; Eyal-Giladi and Kochav, 1976; Sheng  ... 
doi:10.1002/dvdy.24087 pmid:24550174 fatcat:qoctt6sn3jgqfctcdk34be5sny

EMT in developmental morphogenesis

Yukiko Nakaya, Guojun Sheng
2013 Cancer Letters  
Carcinomas, cancers of epithelial origin, constitute the majority of all cancers. Loss of epithelial characteristics is an early step in carcinoma progression. Malignant transformation and metastasis involve additional loss of cell-cycle control and gain of migratory behaviors. Understanding the relationships among epithelial homeostasis, cell proliferation, and cell migration is therefore fundamental in understanding cancer. Interestingly, these cellular events also occur frequently during
more » ... al development, but without leading to tumor formation. Can we learn anything about carcinomas from developmental biology? In this review, we focus on one aspect of carcinoma progression, the Epithelial-Mesenchymal Transition (EMT), and provide an overview of how the EMT is involved in normal amniote development. We discuss 12 developmental and morphogenetic processes that clearly involve the EMT. We conclude by emphasizing the diversity of EMT processes both in terms of their developmental context and of their cellular morphogenesis. We propose that there is comparable diversity in cancer microenvironment and molecular regulation of cancer EMTs.
doi:10.1016/j.canlet.2013.02.037 pmid:23462225 fatcat:ziy73y3y2ng3jplptnpsxvxxvq

Defining epithelial-mesenchymal transitions in animal development

Guojun Sheng
2021 Development  
Amniote gastrulation EMT that gives rise to migratory mesoderm cells is a full EMT (Nakaya and Sheng, 2008) .  ...  These include gastrulation (Bardot and Hadjantonakis, 2020; Keller et al., 2003; Nakaya and Sheng, 2008; Yamashita et al., 2004) , neural crest formation (Ahsan et al., 2019; Piacentino et al., 2020;  ... 
doi:10.1242/dev.198036 pmid:33913481 fatcat:ft5e5uqyajbthogyzvo57rtrvq

On Hemangioblasts in Chicken

Wei Weng, Erike W. Sukowati, Guojun Sheng, Mikhail Blagosklonny
2007 PLoS ONE  
Hemangioblasts are bi-potential precursors for blood and endothelial cells (BCs and ECs). Existence of the hemangioblast in vivo by its strict definition, i.e. a clonal precursor giving rise to these two cell types after division, is still debated. Using a combination of mitotic figure analysis, cell labeling and long-term cell tracing, we show that, in chicken, cell division does not play a major role during the entire ventral mesoderm differentiation process after gastrulation. One eighth of
more » ... ells do undergo at least one round of division, but mainly give rise to daughter cells contributing to the same lineage. Approximately 7% of the dividing cells that contribute to either the BC or EC lineage meet the criteria of true hemangioblasts, with one daughter cell becoming a BC and the other an EC. Our data suggest that hemangioblast-type generation of BC/EC occurs, but is not used as a major mechanism during early chicken development. It remains unclear, however, whether hemangioblast-like progenitor cells play a more prominent role in later development.
doi:10.1371/journal.pone.0001228 pmid:18043736 pmcid:PMC2080762 fatcat:oxkqu7kah5eopko6xpxvgj7ify

Morphogenesis: Eternal truth or ephemeral beauty

Guojun Sheng, Natasza A. Kurpios
2016 Developmental Dynamics  
Reproduced with permission *Correspondence to: or natasza.kurpios@cornell. edu Article is online at: 24381/abstract V C 2016 Wiley  ... 
doi:10.1002/dvdy.24381 pmid:26708750 fatcat:ffycp42klbfwxfeu2y6jttze5y

Epithelial–Mesenchymal Transition in Liver Fluke-Induced Cholangiocarcinoma

Kanlayanee Sawanyawisuth, Goro Sashida, Guojun Sheng
2021 Cancers  
(Guojun Sheng); writing and revision, K.S., G.S. (Goro Sashida) and G.S. (Guojun Sheng). All authors have read and agreed to the published version of the manuscript.  ...  Sheng acknowledges research support from the Japan Society for the Promotion of Science (KA-KEN 18H02452), the Japan Science and Technology Agency (e-ASIA joint research program), and the Takeda Science  ... 
doi:10.3390/cancers13040791 pmid:33672838 pmcid:PMC7917655 fatcat:htynzsokz5ayjjnosupeg76yle

The developmental basis of mesenchymal stem/stromal cells (MSCs)

Guojun Sheng
2015 BMC Developmental Biology  
Mesenchymal Stem/Stromal Cells (MSCs) define a population of progenitor cells capable of giving rises to at least three mesodermal lineages in vitro, the chondrocytes, osteoblasts and adipocytes. The validity of MSCs in vivo has been questioned because their existence, either as a homogeneous progenitor cell population or as a stem cell lineage, has been difficult to prove. The wide use of primary MSCs in regenerative and therapeutic applications raises ethical and regulatory concerns in many
more » ... untries. In contrast to hematopoietic stem cells, a parallel concept which carries an embryological emphasis from its outset, MSCs have attracted little interest among developmental biologists and the embryological basis for their existence, or lack thereof, has not been carefully evaluated. Methods: This article provides a brief, embryological overview of these three mesoderm cell lineages and offers a framework of ontological rationales for the potential existence of MSCs in vivo. Results: Emphasis is given to the common somatic lateral plate mesoderm origin of the majority of body's adipose and skeletal tissues and of the major sources used for MSC derivation clinically. Support for the MSC hypothesis also comes from a large body of molecular and lineage analysis data in vivo. Conclusions: It is concluded that despite the lack of a definitive proof, the MSC concept has a firm embryological basis and that advances in MSC research can be facilitated by achieving a better integration with developmental biology.
doi:10.1186/s12861-015-0094-5 pmid:26589542 pmcid:PMC4654913 fatcat:gxh4wgo6qraxhgatysjjnbzmc4

Context and Attribute Grounded Dense Captioning [article]

Guojun Yin and Lu Sheng and Bin Liu and Nenghai Yu and Xiaogang Wang and Jing Shao
2019 arXiv   pre-print
Dense captioning aims at simultaneously localizing semantic regions and describing these regions-of-interest (ROIs) with short phrases or sentences in natural language. Previous studies have shown remarkable progresses, but they are often vulnerable to the aperture problem that a caption generated by the features inside one ROI lacks contextual coherence with its surrounding context in the input image. In this work, we investigate contextual reasoning based on multi-scale message propagations
more » ... om the neighboring contents to the target ROIs. To this end, we design a novel end-to-end context and attribute grounded dense captioning framework consisting of 1) a contextual visual mining module and 2) a multi-level attribute grounded description generation module. Knowing that captions often co-occur with the linguistic attributes (such as who, what and where), we also incorporate an auxiliary supervision from hierarchical linguistic attributes to augment the distinctiveness of the learned captions. Extensive experiments and ablation studies on Visual Genome dataset demonstrate the superiority of the proposed model in comparison to state-of-the-art methods.
arXiv:1904.01410v1 fatcat:ebnw6mi3e5grbhjaachfakuqae

NPAS4L is involved in avian hemangioblast specification

Wei Weng, Hiroki Nagai, Sofiane Hamidi, Guojun Sheng
2020 Haematologica  
A B C D E F F Wei Weng, Hiroki Nagai, Sofiane Hamidi and Guojun Sheng International Research Center for Medical Sciences (IRCMS), Kumamoto University, Kumamoto, Japan Correspondence: GUOJUN  ...  SHENG doi:10.3324/haematol.2019.239434 haematologica | 2020; 105 (11) Letters to the Editor  ... 
doi:10.3324/haematol.2019.239434 pmid:32054651 pmcid:PMC7604627 fatcat:wuzs7m7255btncovxvhr5yqi6q

Preface Special Issue Epithelial-Mesenchymal Transition 2020

Erik Thompson, Guojun Sheng
2021 Cells Tissues Organs  
Thompson a, b Guojun Sheng c aSchool of Biomedical Sciences, Faculty of Health, Queensland University of Technology (QUT), Brisbane, QLD, Australia; bTranslational Research Institute (TRI), Brisbane  ...  A somewhat nostalgic walk down memory lane in the ship, it is a pleasure to introduce this new Cells Tissues form of a virtual interview by Guojun Sheng of Rik Organs Special Issue arising  ... 
doi:10.1159/000518686 pmid:34348274 fatcat:72o3l63jubcatn5rjp35a44q54

An amicable separation: Chick's way of doing EMT

Yukiko Nakaya, Guojun Sheng
2009 Cell Adhesion & Migration  
Epithelial to mesenchymal transition (EMT) is a morphogenetic process in which cells lose their epithelial characteristics and gain mesenchymal properties, and is fundamental for many tissue remodeling events in developmental and pathological conditions. Although general cell biology of EMT has been well-described, how it is executed in diverse biological settings depends largely on individual context, and as a consequence, regulatory points for each EMT may vary. Here we discuss developmental
more » ... nd cellular events involved in chick gastrulation EMT. Regulated disruption of epithelial cell/basement membrane (BM) interaction is a critical early step. This takes place after molecular specification of mesoderm cell fate, but before the disruption of tight junctions. The epithelial cell/BM interaction is mediated by small GTPase RhoA and through the regulation of basal microtubule dynamics. We propose that EMT is not regulated as a single morphogenetic event. Components of EMT in different settings may share similar regulatory mechanisms, but the sequence of their execution and critical regulatory points vary for each EMT. EMT is a concept proposed in cell biological studies of tissue morphogenesis during embryonic development. 1,2 It involves changes of inter-cellular organization from a two dimensional epithelial type to a three dimensional mesenchymal one. The earliest EMT in animal development occurs during gastrulation, a process that forms mesoderm and endoderm tissue layers from the ectoderm. In amniotes, which include reptiles, birds and mammals, ectoderm cells are organized as an epithelial sheet. EMTs in gastrulation and other developmental settings take place with spatial and temporal constraints, and are coupled with complex patterning and cell fate specification events, most of which are not directly related to EMT. Molecular mechanisms underlying EMT are therefore difficult to be teased out. Furthermore, EMT is often defined in literature to include morphogenetic events within the epithelial sheet and mesenchymal cell population, which in strict sense should not be regarded as such. The descriptive power of EMT has been based on detailed cell biological studies, which may also be critical for current molecular studies of EMT. Here we use chick as an example to discuss the developmental, morphogenetic and cellular aspects that set the stage for gastrulation EMT. Before formation of mesoderm and definitive endoderm, chick embryo is composed of two layers, epiblast and hypoblast, in area pellucida from which all intraembryonic tissues develop (Fig. 1A) . 3 The hypoblast is a part of primitive endoderm and is formed by cells segregated from an earlier multilayered epiblast before its epithelialization into a single-cell-thick layer. During gastrulation, the epiblast is stretched tight as a result of adhesion and outward migration of its marginal cells in area opaca over acellular vitelline membrane. 4,5 In the area pellucida, epiblast cells are also covered by the vitelline membrane, but without obvious adhesion or interaction between them. Epiblast integrity is maintained mainly by tight junctions present in every epiblast cell. Mesoderm cells form through a de-epithelialization process, i.e., EMT, from the epiblast. Where, when and how EMT takes place to generate mesoderm are influenced by a number of developmental factors that are not directly related to the regulation EMT. The primitive streak (streak), the site of EMT, is a dynamic structure. It is specified at posterior part of the area pellucida by an earlier dorsal/ventral patterning event at stage HH1. Elongation of the streak anterior-ward occurs from HH2 to HH4, regulated by "global" tissue morphogenetic movement within the epiblast plane. 6 The streak then retracts as development proceeds, and by HH9-10, regresses to a small region at the posterior end of the embryo. Throughout its elongation and retraction, the streak continues to generate mesoderm cells, but general morphology of the streak and its physical relationship with other developing tissues change, which affects how EMT takes place at the cellular level. In addition, mesoderm cell formation involves their concurrent patterning. Specification of different mesoderm lineages along the dorsal/ventral axis of the embryo is reflected in relative anterior/posterior locations of precursors in the streak, and a separate anterior/posterior patterning event is reflected in the timing of precursor cell ingression within each lineage. 7 These patterning events lead to variations of EMT even within the narrow definition of chick gastrulation. Moreover, the streak also serves as a signaling center in patterning neighboring ectoderm and in defining ectoderm/mesoderm boundary together with ectoderm derived signals. Thus cells located in and immediately near the streak are making constant decisions of whether to go in and become mesoderm or to
doi:10.4161/cam.3.2.7373 pmid:19262172 pmcid:PMC2679875 fatcat:d7thz4qiezg6fpaw72y7vsivvy

Cell Shape and Cell Lineage Conversion

Yukiko Nakaya, Guojun Sheng
2015 The Journal of Poultry Science  
A prominent feature of the paraxial mesoderm lineage (cells destined to form the dermis, muscles and axial bones) is to initiate an MET event, giving rise to transitory epithelialized Nakaya and Sheng:  ...  2005) , the birds are increasingly becoming a tractable model system for genetics (Nishijima and Iijima, 2013) , cancer (Kain et al., 2014) and pluripotency (Alev et al., 2013; Jean et al., 2013; Sheng  ... 
doi:10.2141/jpsa.0140088 fatcat:5wljzj7bvfgkjmrnw3riw5nn5y

Semantics Disentangling for Text-to-Image Generation [article]

Guojun Yin and Bin Liu and Lu Sheng and Nenghai Yu and Xiaogang Wang and Jing Shao
2019 arXiv   pre-print
[40, 37, 42, 14, 29] mainly focus on increasing the visual quality and resolution of the generated images by either a stacked coarseto-fine generator structure [40, 14] or an attention-guided * Lu Sheng  ... 
arXiv:1904.01480v1 fatcat:jrzpz5eez5abrbm4ewiuivavj4
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