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Tang Y, Chen Y, Liu R, Li W, Hua B, Bao Y. Wnt Signaling Pathways: A Role in Pain Processing. Neuromolecular Med 2022; 24:233-249. [PMID: 35067780 PMCID: PMC9402773 DOI: 10.1007/s12017-021-08700-z] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Accepted: 11/30/2021] [Indexed: 10/25/2022]
Abstract
The wingless-related integration site (Wnt) signaling pathway plays an essential role in embryonic development and nervous system regulation. It is critically involved in multiple types of neuropathic pain (NP), such as HIV-related NP, cancer pain, diabetic neuralgia, multiple sclerosis-related NP, endometriosis pain, and other painful diseases. Wnt signaling is also implicated in the pain induced by sciatic nerve compression injury and selective spinal nerve ligation. Thus, the Wnt signaling pathway may be a potential therapeutic target for NP.
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Affiliation(s)
- Yiting Tang
- Guang'anmen Hospital, China Academy of Chinese Medical Sciences, Beixiange 5, Xicheng District, Beijing, 100053, China
- Beijing University of Chinese Medicine, Beijing North Third Ring Road No. 11, Chaoyang District, Beijing, 100029, China
| | - Yupeng Chen
- Guang'anmen Hospital, China Academy of Chinese Medical Sciences, Beixiange 5, Xicheng District, Beijing, 100053, China
- Beijing University of Chinese Medicine, Beijing North Third Ring Road No. 11, Chaoyang District, Beijing, 100029, China
| | - Rui Liu
- Department of Oncology, Guang'anmen Hospital, China Academy of Chinese Medical Sciences, Beixiange 5, Xicheng District, Beijing, 100053, China
| | - Weidong Li
- Department of Oncology, Guang'anmen Hospital, China Academy of Chinese Medical Sciences, Beixiange 5, Xicheng District, Beijing, 100053, China
| | - Baojin Hua
- Department of Oncology, Guang'anmen Hospital, China Academy of Chinese Medical Sciences, Beixiange 5, Xicheng District, Beijing, 100053, China.
| | - Yanju Bao
- Department of Oncology, Guang'anmen Hospital, China Academy of Chinese Medical Sciences, Beixiange 5, Xicheng District, Beijing, 100053, China.
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2
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Martín-Salazar JE, Valverde D. CPLANE Complex and Ciliopathies. Biomolecules 2022; 12:biom12060847. [PMID: 35740972 PMCID: PMC9221175 DOI: 10.3390/biom12060847] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2022] [Revised: 06/10/2022] [Accepted: 06/16/2022] [Indexed: 02/04/2023] Open
Abstract
Primary cilia are non-motile organelles associated with the cell cycle, which can be found in most vertebrate cell types. Cilia formation occurs through a process called ciliogenesis, which involves several mechanisms including planar cell polarity (PCP) and the Hedgehog (Hh) signaling pathway. Some gene complexes, such as BBSome or CPLANE (ciliogenesis and planar polarity effector), have been linked to ciliogenesis. CPLANE complex is composed of INTU, FUZ and WDPCP, which bind to JBTS17 and RSG1 for cilia formation. Defects in these genes have been linked to a malfunction of intraflagellar transport and defects in the planar cell polarity, as well as defective activation of the Hedgehog signalling pathway. These faults lead to defective cilium formation, resulting in ciliopathies, including orofacial-digital syndrome (OFDS) and Bardet-Biedl syndrome (BBS). Considering the close relationship, between the CPLANE complex and cilium formation, it can be expected that defects in the genes that encode subunits of the CPLANE complex may be related to other ciliopathies.
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Affiliation(s)
| | - Diana Valverde
- CINBIO, Biomedical Research Centre, University of Vigo, 36310 Vigo, Spain;
- Galicia Sur Health Research Institute (IIS-GS), 36310 Vigo, Spain
- Correspondence:
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Beljan S, Herak Bosnar M, Ćetković H. Rho Family of Ras-Like GTPases in Early-Branching Animals. Cells 2020; 9:cells9102279. [PMID: 33066017 PMCID: PMC7600811 DOI: 10.3390/cells9102279] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2020] [Revised: 10/06/2020] [Accepted: 10/09/2020] [Indexed: 02/07/2023] Open
Abstract
Non-bilaterian animals consist of four phyla; Porifera, Cnidaria, Ctenophora, and Placozoa. These early-diverging animals are crucial for understanding the evolution of the entire animal lineage. The Rho family of proteins make up a major branch of the Ras superfamily of small GTPases, which function as key molecular switches that play important roles in converting and amplifying external signals into cellular responses. This review represents a compilation of the current knowledge on Rho-family GTPases in non-bilaterian animals, the available experimental data about their biochemical characteristics and functions, as well as original bioinformatics analysis, in order to gain a general insight into the evolutionary history of Rho-family GTPases in simple animals.
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Affiliation(s)
- Silvestar Beljan
- Division of Molecular Biology, Ruđer Bošković Institute, HR-10000 Zagreb, Croatia;
- Division of Molecular Biology, Faculty of Science, University of Zagreb, HR-10000 Zagreb, Croatia
| | - Maja Herak Bosnar
- Division of Molecular Medicine, Ruđer Bošković Institute, HR-10000 Zagreb, Croatia;
| | - Helena Ćetković
- Division of Molecular Biology, Ruđer Bošković Institute, HR-10000 Zagreb, Croatia;
- Correspondence: ; Tel.: +385-1-456-1115
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Carreira-Barbosa F, Nunes SC. Wnt Signaling: Paths for Cancer Progression. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2020; 1219:189-202. [PMID: 32130700 DOI: 10.1007/978-3-030-34025-4_10] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The Wnt signaling pathways are well known for having several pivotal roles during embryonic development. However, the same developmental signaling pathways also present key roles in cancer initiation and progression. In this chapter, several issues regarding the roles of both canonical and non-canonical Wnt signaling pathways in cancer will be explored, mainly concerning their role in the maintenance of cancer stemness, in the metabolism reprograming of cancer cells and in the modulation of the tumor microenvironment. The role of Wnt signaling cascades in the response of cancer cells to anti-cancer treatments will be also discussed, as well as its potential therapeutic targeting during cancer treatment. Collectively, increasing evidence has been supporting pivotal roles of Wnt signaling in several features of cancer biology, however; a lot is still to be elucidated.
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Affiliation(s)
| | - Sofia C Nunes
- CEDOC, Chronic Diseases Research Centre, NOVA Medical School | Faculdade de Ciências Médicas, Universidade NOVA de Lisboa, Lisbon, Portugal
- Instituto Português de Oncologia de Lisboa Francisco Gentil (IPOLFG), Lisbon, Portugal
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5
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Yancan L, Tianle C, Yunhan F, Delong L, Guizhi W. Population genomics and morphological features underlying the adaptive evolution of the eastern honey bee (Apis cerana). BMC Genomics 2019; 20:869. [PMID: 31730443 PMCID: PMC6858728 DOI: 10.1186/s12864-019-6246-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2019] [Accepted: 10/30/2019] [Indexed: 12/19/2022] Open
Abstract
Background The adaptation of organisms to changing environments is self-evident, with the adaptive evolution of organisms to environmental changes being a fundamental problem in evolutionary biology. Bees can pollinate in various environments and climates and play important roles in maintaining the ecological balance of the earth. Results We performed an analysis of 462 Apis cerana (A. cerana) specimens from 31 populations in 11 regions and obtained 39 representative morphological features. We selected 8 A. cerana samples from each population and performed 2b-RAD simplified genome sequencing. A total of 11,506 high-quality single nucleotide polymorphism (SNP) loci were obtained. For these SNPs, the minor allele frequency (MAF) was > 1%, the average number of unique labels for each sample was 49,055, and the average depth was 72.61x. The ratios of the unique labels of all samples were 64.27–86.33%. Conclusions Using 39 morphological characteristics as the data set, we proposed a method for the rapid classification of A. cerana. Using genomics to assess population structure and genetic diversity, we found that A. cerana has a large genetic difference at the ecotype level. A comparison of A. cerana in North China revealed that some physical obstacles, especially the overurbanization of the plains, have isolated the populations of this species. We identified several migration events in North China and Central China. By comparing the differences in the environmental changes in different regions, we found that A. cerana has strong potential for climate change and provides a theoretical basis for investigating and protecting A. cerana.
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Affiliation(s)
- Li Yancan
- Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control and Prevention, Shandong Agricultural University, 61 Daizong Street, Tai'an, 271018, Shandong Province, People's Republic of China
| | - Chao Tianle
- Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control and Prevention, Shandong Agricultural University, 61 Daizong Street, Tai'an, 271018, Shandong Province, People's Republic of China
| | - Fan Yunhan
- Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control and Prevention, Shandong Agricultural University, 61 Daizong Street, Tai'an, 271018, Shandong Province, People's Republic of China
| | - Lou Delong
- Shandong Apiculture Breeding of Improved Varieties and Extension Center, 186 Wuma Street, Tai'an, 271000, Shandong Province, People's Republic of China
| | - Wang Guizhi
- Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control and Prevention, Shandong Agricultural University, 61 Daizong Street, Tai'an, 271018, Shandong Province, People's Republic of China.
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6
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Gerondopoulos A, Strutt H, Stevenson NL, Sobajima T, Levine TP, Stephens DJ, Strutt D, Barr FA. Planar Cell Polarity Effector Proteins Inturned and Fuzzy Form a Rab23 GEF Complex. Curr Biol 2019; 29:3323-3330.e8. [PMID: 31564489 PMCID: PMC6864590 DOI: 10.1016/j.cub.2019.07.090] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2019] [Revised: 07/26/2019] [Accepted: 07/31/2019] [Indexed: 01/12/2023]
Abstract
A subset of Rab GTPases have been implicated in cilium formation in cultured mammalian cells [1-6]. Rab11 and Rab8, together with their GDP-GTP exchange factors (GEFs), TRAPP-II and Rabin8, promote recruitment of the ciliary vesicle to the mother centriole and its subsequent maturation, docking, and fusion with the cell surface [2-5]. Rab23 has been linked to cilium formation and membrane trafficking at mature cilia [1, 7, 8]; however, the identity of the GEF pathway activating Rab23, a member of the Rab7 subfamily of Rabs, remains unclear. Longin-domain-containing complexes have been shown to act as GEFs for Rab7 subfamily GTPases [9-12]. Here, we show that Inturned and Fuzzy, proteins previously implicated as planar cell polarity (PCP) effectors and in developmentally regulated cilium formation [13, 14], contain multiple longin domains characteristic of the Mon1-Ccz1 family of Rab7 GEFs and form a specific Rab23 GEF complex. In flies, loss of Rab23 function gave rise to defects in planar-polarized trichome formation consistent with this biochemical relationship. In cultured human and mouse cells, Inturned and Fuzzy localized to the basal body and proximal region of cilia, and cilium formation was compromised by depletion of either Inturned or Fuzzy. Cilium formation arrested after docking of the ciliary vesicle to the mother centriole but prior to axoneme elongation and fusion of the ciliary vesicle and plasma membrane. These findings extend the family of longin domain GEFs and define a molecular activity linking Rab23-regulated membrane traffic to cilia and planar cell polarity.
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Affiliation(s)
- Andreas Gerondopoulos
- Department of Biochemistry, University of Oxford, South Parks Road, Oxford OX1 3QU, UK
| | - Helen Strutt
- Department of Biomedical Science, University of Sheffield, Firth Court, Sheffield S10 2TN, UK
| | - Nicola L Stevenson
- School of Biochemistry, University of Bristol, Biomedical Sciences Building, University Walk, Bristol BS8 1TD, UK
| | - Tomoaki Sobajima
- Department of Biochemistry, University of Oxford, South Parks Road, Oxford OX1 3QU, UK
| | - Tim P Levine
- Institute of Ophthalmology, University College London, 11-43 Bath St., London EC1V 9EL, UK
| | - David J Stephens
- School of Biochemistry, University of Bristol, Biomedical Sciences Building, University Walk, Bristol BS8 1TD, UK
| | - David Strutt
- Department of Biomedical Science, University of Sheffield, Firth Court, Sheffield S10 2TN, UK
| | - Francis A Barr
- Department of Biochemistry, University of Oxford, South Parks Road, Oxford OX1 3QU, UK.
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Xia W, Hu J, Liu F, Ma J, Sun S, Zhang J, Jin K, Huang J, Jiang N, Wang X, Li W, Ma Z, Ma D. New role of LRP5, associated with nonsyndromic autosomal-recessive hereditary hearing loss. Hum Mutat 2017; 38:1421-1431. [PMID: 28677207 DOI: 10.1002/humu.23285] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2016] [Revised: 06/19/2017] [Accepted: 06/25/2017] [Indexed: 12/14/2022]
Abstract
Human hearing loss is a common neurosensory disorder about which many basic research and clinically relevant questions are unresolved. At least 50% of hearing loss are due to a genetic etiology. Although hundreds of genes have been reported, there are still hundreds of related deafness genes to be found. Clinical, genetic, and functional investigations were performed to identify the causative mutation in a distinctive Chinese family with postlingual nonsyndromic sensorineural hearing loss. Whole-exome sequencing (WES) identified lipoprotein receptor-related protein 5 (LRP5), a member of the low-density lipoprotein receptor family, as the causative gene in this family. In the zebrafish model, lrp5 downregulation using morpholinos led to significant abnormalities in zebrafish inner ear and lateral line neuromasts and contributed, to some extent, to disabilities in hearing and balance. Rescue experiments showed that LRP5 mutation is associated with hearing loss. Knocking down lrp5 in zebrafish results in reduced expression of several genes linked to Wnt signaling pathway and decreased cell proliferation when compared with those in wild-type zebrafish. In conclusion, the LRP5 mutation influences cell proliferation through the Wnt signaling pathway, thereby reducing the number of supporting cells and hair cells and leading to nonsyndromic hearing loss in this Chinese family.
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Affiliation(s)
- Wenjun Xia
- Institutes of Biomedical Science, Fudan University, Shanghai, China
| | - Jiongjiong Hu
- Department of Otorhinolaryngology, Shanghai East Hospital, Tongji University, Shanghai, China
| | - Fei Liu
- Key Laboratory of Metabolism and Molecular Medicine, Ministry of Education, Department of Biochemistry and Molecular Biology, Institute of Biomedical Sciences, Collaborative Innovation Center of Genetics and Development, School of Basic Medical Sciences, Fudan University, Shanghai, China
| | - Jing Ma
- Key Laboratory of Metabolism and Molecular Medicine, Ministry of Education, Department of Biochemistry and Molecular Biology, Institute of Biomedical Sciences, Collaborative Innovation Center of Genetics and Development, School of Basic Medical Sciences, Fudan University, Shanghai, China.,Center Laboratory, Bao'an Maternal and Children Healthcare Hospital, Key Laboratory of Birth Defects Research, Shenzhen, China
| | - Shaoyang Sun
- Key Laboratory of Metabolism and Molecular Medicine, Ministry of Education, Department of Biochemistry and Molecular Biology, Institute of Biomedical Sciences, Collaborative Innovation Center of Genetics and Development, School of Basic Medical Sciences, Fudan University, Shanghai, China
| | - Jin Zhang
- Key Laboratory of Metabolism and Molecular Medicine, Ministry of Education, Department of Biochemistry and Molecular Biology, Institute of Biomedical Sciences, Collaborative Innovation Center of Genetics and Development, School of Basic Medical Sciences, Fudan University, Shanghai, China
| | - Kaiyue Jin
- Key Laboratory of Metabolism and Molecular Medicine, Ministry of Education, Department of Biochemistry and Molecular Biology, Institute of Biomedical Sciences, Collaborative Innovation Center of Genetics and Development, School of Basic Medical Sciences, Fudan University, Shanghai, China
| | - Jianbo Huang
- Key Laboratory of Metabolism and Molecular Medicine, Ministry of Education, Department of Biochemistry and Molecular Biology, Institute of Biomedical Sciences, Collaborative Innovation Center of Genetics and Development, School of Basic Medical Sciences, Fudan University, Shanghai, China
| | - Nan Jiang
- Key Laboratory of Metabolism and Molecular Medicine, Ministry of Education, Department of Biochemistry and Molecular Biology, Institute of Biomedical Sciences, Collaborative Innovation Center of Genetics and Development, School of Basic Medical Sciences, Fudan University, Shanghai, China
| | - Xu Wang
- Key Laboratory of Metabolism and Molecular Medicine, Ministry of Education, Department of Biochemistry and Molecular Biology, Institute of Biomedical Sciences, Collaborative Innovation Center of Genetics and Development, School of Basic Medical Sciences, Fudan University, Shanghai, China
| | - Wen Li
- Eye & ENT Hospital, Fudan University, Shanghai, China
| | - Zhaoxin Ma
- Department of Otorhinolaryngology, Shanghai East Hospital, Tongji University, Shanghai, China
| | - Duan Ma
- Institutes of Biomedical Science, Fudan University, Shanghai, China.,Key Laboratory of Metabolism and Molecular Medicine, Ministry of Education, Department of Biochemistry and Molecular Biology, Institute of Biomedical Sciences, Collaborative Innovation Center of Genetics and Development, School of Basic Medical Sciences, Fudan University, Shanghai, China.,Children's Hospital, Fudan University, Shanghai, China
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Ikehata M, Yamada A, Morimura N, Itose M, Suzawa T, Shirota T, Chikazu D, Kamijo R. Wnt/β-catenin signaling activates nephronectin expression in osteoblasts. Biochem Biophys Res Commun 2017; 484:231-234. [PMID: 28093227 DOI: 10.1016/j.bbrc.2017.01.053] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2016] [Accepted: 01/11/2017] [Indexed: 02/06/2023]
Abstract
Nephronectin (Npnt), an extracellular matrix protein, is considered to play critical roles as an adhesion molecule in the development and functions of various organs and tissues, such as the kidneys and bone. In the present study, we found that Wnt3a strongly enhanced Npnt mRNA expression in osteoblast-like MC3T3-E1 cells, while it also induced an increase in Npnt gene expression in both time- and dose-dependent manners via the Wnt/β-catenin signaling pathway. These results suggest novel mechanisms for Wnt3a-induced osteoblast proliferation and cell survival via Npnt gene expression.
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Affiliation(s)
- Mikiko Ikehata
- Department of Biochemistry, School of Dentistry, Showa University, Tokyo, Japan; Department of Oral and Maxillofacial Surgery, Tokyo Medical University, Tokyo, Japan
| | - Atsushi Yamada
- Department of Biochemistry, School of Dentistry, Showa University, Tokyo, Japan.
| | - Naoko Morimura
- Department of Integrative Physiology, Shiga University of Medical Science, Shiga, Japan
| | - Masakatsu Itose
- Department of Biochemistry, School of Dentistry, Showa University, Tokyo, Japan; Department of Oral and Maxillofacial Surgery, School of Dentistry, Showa University, Tokyo, Japan
| | - Tetsuo Suzawa
- Department of Biochemistry, School of Dentistry, Showa University, Tokyo, Japan
| | - Tatsuo Shirota
- Department of Oral and Maxillofacial Surgery, School of Dentistry, Showa University, Tokyo, Japan
| | - Daichi Chikazu
- Department of Oral and Maxillofacial Surgery, Tokyo Medical University, Tokyo, Japan
| | - Ryutaro Kamijo
- Department of Biochemistry, School of Dentistry, Showa University, Tokyo, Japan
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Nayak L, Bhattacharyya NP, De RK. Wnt signal transduction pathways: modules, development and evolution. BMC SYSTEMS BIOLOGY 2016; 10 Suppl 2:44. [PMID: 27490822 PMCID: PMC4977476 DOI: 10.1186/s12918-016-0299-7] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
BACKGROUND Wnt signal transduction pathway (Wnt STP) is a crucial intracellular pathway mainly due to its participation in important biological processes, functions, and diseases, i.e., embryonic development, stem-cell management, and human cancers among others. This is why Wnt STP is one of the highest researched signal transduction pathways. Study and analysis of its origin, expansion and gradual development to the present state as found in humans is one aspect of Wnt research. The pattern of development and evolution of the Wnt STP among various species is not clear till date. A phylogenetic tree created from Wnt STPs of multiple species may address this issue. RESULTS In this respect, we construct a phylogenetic tree from modules of Wnt STPs of diverse species. We term it as the 'Module Tree'. A module is nothing but a self-sufficient minimally-dependent subset of the original Wnt STP. Authenticity of the module tree is tested by comparing it with the two reference trees. CONCLUSIONS The module tree performs better than an alternative phylogenetic tree constructed from pathway topology of Wnt STPs. Moreover, an evolutionary emergence pattern of the Wnt gene family is created and the module tree is tallied with it to showcase the significant resemblances.
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Affiliation(s)
- Losiana Nayak
- Indian Statistical Institute, 203 Barrackpore Trunk Road, Kolkata, 700108 India
| | - Nitai P. Bhattacharyya
- Saha Institute of Nuclear Physics, 1/AF Bidhan Nagar, Kolkata, 700064 India
- Present Affiliation: Biomedical Genomics Centre, 5 Suburban Hospital Road, Kolkata, 700020 India
| | - Rajat K. De
- Indian Statistical Institute, 203 Barrackpore Trunk Road, Kolkata, 700108 India
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Sassi N, Laadhar L, Allouche M, Achek A, Kallel-Sellami M, Makni S, Sellami S. WNT signaling and chondrocytes: from cell fate determination to osteoarthritis physiopathology. J Recept Signal Transduct Res 2013; 34:73-80. [PMID: 24303940 DOI: 10.3109/10799893.2013.863919] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
CONTEXT Osteoarthritis (OA) is an articular disorder leading to the degradation of articular cartilage phenotypical chondrocytes modifications, including the acquisition of a fibroblast-like morphology, decreased expression of collagen type II, and increased expression of fetal collagen type I, metalloproteinase 13 and nitric oxide synthase. This promotes matrix degradation and unsuccessful cartilage repair. WNT signaling constitutes one of the most critical biological processes during cell fate assignment and homeostasis. OBJECTIVES This review aims to give an insight on results from the studies that were interested in the involvement of WNT in OA. METHODS Studies were selected through a pubmed search. RESULTS Recent genetic data showed that aberration in WNT signaling may be involved in OA. WNT signals are transduced through at least three cascades: the canonical WNT/β-catenin pathway, the WNT/Ca(2+) pathway and the WNT/planar cell polarity pathway. Most of the studies used in-vitro models to elucidate the involvement of WNT in the physiopathology of OA. These studies analyzed the expression pattern of WNT pathway components during OA such as WNT5, WNT7, co-receptor LRP, β-catenin, WNT target genes (c-jun, cyclins) and/or the interaction of these components with the secretion of OA most important markers such as IL-1, collagens, MMPs. Results from these studies are in favor of a deep involvement of the WNT signaling in the physiopathology of OA either by having a protective or a destructive role. CONCLUSION Deeper researches may eventually allow scientists to target WNT pathway in order to help develop efficient therapeutic approaches to treat OA.
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Affiliation(s)
- Nadia Sassi
- Immuno-Rheumatology Research Laboratory, Rheumatology Department, La Rabta Hospital, University of Tunis-El Manar , Tunis , Tunisia and
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11
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Panaccione I, Napoletano F, Forte AM, Kotzalidis GD, Del Casale A, Rapinesi C, Brugnoli C, Serata D, Caccia F, Cuomo I, Ambrosi E, Simonetti A, Savoja V, De Chiara L, Danese E, Manfredi G, Janiri D, Motolese M, Nicoletti F, Girardi P, Sani G. Neurodevelopment in schizophrenia: the role of the wnt pathways. Curr Neuropharmacol 2013; 11:535-58. [PMID: 24403877 PMCID: PMC3763761 DOI: 10.2174/1570159x113119990037] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2012] [Revised: 03/28/2013] [Accepted: 05/12/2013] [Indexed: 02/06/2023] Open
Abstract
OBJECTIVES To review the role of Wnt pathways in the neurodevelopment of schizophrenia. METHODS SYSTEMATIC PUBMED SEARCH, USING AS KEYWORDS ALL THE TERMS RELATED TO THE WNT PATHWAYS AND CROSSING THEM WITH EACH OF THE FOLLOWING AREAS: normal neurodevelopment and physiology, neurodevelopmental theory of schizophrenia, schizophrenia, and antipsychotic drug action. RESULTS Neurodevelopmental, behavioural, genetic, and psychopharmacological data point to the possible involvement of Wnt systems, especially the canonical pathway, in the pathophysiology of schizophrenia and in the mechanism of antipsychotic drug action. The molecules most consistently found to be associated with abnormalities or in antipsychotic drug action are Akt1, glycogen synthase kinase3beta, and beta-catenin. However, the extent to which they contribute to the pathophysiology of schizophrenia or to antipsychotic action remains to be established. CONCLUSIONS The study of the involvement of Wnt pathway abnormalities in schizophrenia may help in understanding this multifaceted clinical entity; the development of Wnt-related pharmacological targets must await the collection of more data.
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Affiliation(s)
- Isabella Panaccione
- NESMOS Department (Neuroscience, Mental Health, and Sensory Organs), Sapienza University, School of Medicine and Psychology, Sant’Andrea Hospital, Rome, Italy
| | - Flavia Napoletano
- NESMOS Department (Neuroscience, Mental Health, and Sensory Organs), Sapienza University, School of Medicine and Psychology, Sant’Andrea Hospital, Rome, Italy
| | - Alberto Maria Forte
- NESMOS Department (Neuroscience, Mental Health, and Sensory Organs), Sapienza University, School of Medicine and Psychology, Sant’Andrea Hospital, Rome, Italy
| | - Giorgio D. Kotzalidis
- NESMOS Department (Neuroscience, Mental Health, and Sensory Organs), Sapienza University, School of Medicine and Psychology, Sant’Andrea Hospital, Rome, Italy
| | - Antonio Del Casale
- NESMOS Department (Neuroscience, Mental Health, and Sensory Organs), Sapienza University, School of Medicine and Psychology, Sant’Andrea Hospital, Rome, Italy
| | - Chiara Rapinesi
- NESMOS Department (Neuroscience, Mental Health, and Sensory Organs), Sapienza University, School of Medicine and Psychology, Sant’Andrea Hospital, Rome, Italy
| | - Chiara Brugnoli
- NESMOS Department (Neuroscience, Mental Health, and Sensory Organs), Sapienza University, School of Medicine and Psychology, Sant’Andrea Hospital, Rome, Italy
| | - Daniele Serata
- NESMOS Department (Neuroscience, Mental Health, and Sensory Organs), Sapienza University, School of Medicine and Psychology, Sant’Andrea Hospital, Rome, Italy
| | - Federica Caccia
- NESMOS Department (Neuroscience, Mental Health, and Sensory Organs), Sapienza University, School of Medicine and Psychology, Sant’Andrea Hospital, Rome, Italy
| | - Ilaria Cuomo
- NESMOS Department (Neuroscience, Mental Health, and Sensory Organs), Sapienza University, School of Medicine and Psychology, Sant’Andrea Hospital, Rome, Italy
| | - Elisa Ambrosi
- NESMOS Department (Neuroscience, Mental Health, and Sensory Organs), Sapienza University, School of Medicine and Psychology, Sant’Andrea Hospital, Rome, Italy
| | - Alessio Simonetti
- NESMOS Department (Neuroscience, Mental Health, and Sensory Organs), Sapienza University, School of Medicine and Psychology, Sant’Andrea Hospital, Rome, Italy
| | - Valeria Savoja
- NESMOS Department (Neuroscience, Mental Health, and Sensory Organs), Sapienza University, School of Medicine and Psychology, Sant’Andrea Hospital, Rome, Italy
| | - Lavinia De Chiara
- NESMOS Department (Neuroscience, Mental Health, and Sensory Organs), Sapienza University, School of Medicine and Psychology, Sant’Andrea Hospital, Rome, Italy
| | - Emanuela Danese
- NESMOS Department (Neuroscience, Mental Health, and Sensory Organs), Sapienza University, School of Medicine and Psychology, Sant’Andrea Hospital, Rome, Italy
| | - Giovanni Manfredi
- NESMOS Department (Neuroscience, Mental Health, and Sensory Organs), Sapienza University, School of Medicine and Psychology, Sant’Andrea Hospital, Rome, Italy
| | - Delfina Janiri
- NESMOS Department (Neuroscience, Mental Health, and Sensory Organs), Sapienza University, School of Medicine and Psychology, Sant’Andrea Hospital, Rome, Italy
| | | | - Ferdinando Nicoletti
- NEUROMED, Pozzilli, Isernia, Italy
- Department of Neuropharmacology, Sapienza University, School of Medicine and Pharmacy, Rome, Italy
| | - Paolo Girardi
- NESMOS Department (Neuroscience, Mental Health, and Sensory Organs), Sapienza University, School of Medicine and Psychology, Sant’Andrea Hospital, Rome, Italy
- Centro Lucio Bini, Rome, Italy
| | - Gabriele Sani
- NESMOS Department (Neuroscience, Mental Health, and Sensory Organs), Sapienza University, School of Medicine and Psychology, Sant’Andrea Hospital, Rome, Italy
- Centro Lucio Bini, Rome, Italy
- IRCCS Santa Lucia Foundation, Department of Clinical and Behavioural Neurology, Neuropsychiatry Laboratory, Rome, Italy
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12
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Sassi N, Laadhar L, Allouche M, Zandieh-Doulabi B, Hamdoun M, Klein-Nulend J, Makni S, Sellami S. The roles of canonical and non-canonical Wnt signaling in human de-differentiated articular chondrocytes. Biotech Histochem 2013; 89:53-65. [PMID: 23901950 DOI: 10.3109/10520295.2013.819123] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Osteoarthritis is the most prevalent form of arthritis in the world and it is becoming a major public health problem. Osteoarthritic chondrocytes undergo morphological and biochemical changes that lead to de-differentiation. The involvement of signaling pathways, such as the Wnt pathway, during cartilage pathology has been reported. Wnt signaling regulates critical biological processes. Wnt signals are transduced through at least three intracellular signaling pathways including the canonical Wnt/β-catenin pathway, the Wnt/Ca2 + pathway and the Wnt/planar cell polarity pathway. We investigated the involvement of the Wnt canonical and non-canonical pathways in human articular chondrocyte de-differentiation in vitro. Human articular chondrocytes were cultured through four passages with no treatment, or with sFRP3 treatment, an inhibitor of Wnt pathways, or with DKK1 treatment, an inhibitor of the canonical pathway. Chondrocyte-secreted markers and Wnt pathway components were analyzed using western blotting and qPCR. Inhibition of the Wnt pathway showed that the canonical Wnt signaling probably is responsible for inhibition of collagen II expression, activation of metalloproteinase 13 expression and regulation of Wnt7a and c-jun expression during chondrocyte de-differentiation in vitro. Our results also suggest that expressions of eNOS, Wnt5a and cyclinE1 are regulated by non-canonical Wnt signaling.
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Affiliation(s)
- N Sassi
- Immuno-Rheumatology research laboratory, Rheumatology Department, La Rabta Hospital, University of Tunis-El Manar
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13
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Ma B, Landman EBM, Miclea RL, Wit JM, Robanus-Maandag EC, Post JN, Karperien M. WNT signaling and cartilage: of mice and men. Calcif Tissue Int 2013; 92:399-411. [PMID: 23212543 DOI: 10.1007/s00223-012-9675-5] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/06/2012] [Accepted: 11/03/2012] [Indexed: 01/08/2023]
Abstract
In adult articular cartilage, the extracellular matrix is maintained by a balance between the degradation and the synthesis of matrix components. Chondrocytes that sparsely reside in the matrix and rarely proliferate are the key cellular mediators for cartilage homeostasis. There are indications for the involvement of the WNT signaling pathway in maintaining articular cartilage. Various WNTs are involved in the subsequent stages of chondrocyte differentiation during development, and deregulation of WNT signaling was observed in cartilage degeneration. Even though gene expression and protein synthesis can be activated upon injury, articular cartilage has a limited ability of self-repair and efforts to regenerate articular cartilage have so far not been successful. Because WNT signaling was found to be involved in the development and maintenance of cartilage as well as in the degeneration of cartilage, interfering with this pathway might contribute to improving cartilage regeneration. However, most of the studies on elucidating the role of WNT signaling in these processes were conducted using in vitro or in vivo animal models. Discrepancies have been found in the role of WNT signaling between chondrocytes of mouse and human origin, and extrapolation of results from mouse models to the human situation remains a challenge. Elucidation of detailed WNT signaling functions will provide knowledge to improve cartilage regeneration.
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Affiliation(s)
- Bin Ma
- Department of Developmental BioEngineering, University of Twente, Drienerlolaan 5, 7522NB, Enschede, The Netherlands
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14
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Zhang Z, Wlodarczyk BJ, Niederreither K, Venugopalan S, Florez S, Finnell RH, Amendt BA. Fuz regulates craniofacial development through tissue specific responses to signaling factors. PLoS One 2011; 6:e24608. [PMID: 21935430 PMCID: PMC3173472 DOI: 10.1371/journal.pone.0024608] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2011] [Accepted: 08/14/2011] [Indexed: 02/07/2023] Open
Abstract
The planar cell polarity effector gene Fuz regulates ciliogenesis and Fuz loss of function studies reveal an array of embryonic phenotypes. However, cilia defects can affect many signaling pathways and, in humans, cilia defects underlie several craniofacial anomalies. To address this, we analyzed the craniofacial phenotype and signaling responses of the Fuz−/− mice. We demonstrate a unique role for Fuz in regulating both Hedgehog (Hh) and Wnt/β-catenin signaling during craniofacial development. Fuz expression first appears in the dorsal tissues and later in ventral tissues and craniofacial regions during embryonic development coincident with cilia development. The Fuz−/− mice exhibit severe craniofacial deformities including anophthalmia, agenesis of the tongue and incisors, a hypoplastic mandible, cleft palate, ossification/skeletal defects and hyperplastic malformed Meckel's cartilage. Hh signaling is down-regulated in the Fuz null mice, while canonical Wnt signaling is up-regulated revealing the antagonistic relationship of these two pathways. Meckel's cartilage is expanded in the Fuz−/− mice due to increased cell proliferation associated with the up-regulation of Wnt canonical target genes and decreased non-canonical pathway genes. Interestingly, cilia development was decreased in the mandible mesenchyme of Fuz null mice, suggesting that cilia may antagonize Wnt signaling in this tissue. Furthermore, expression of Fuz decreased expression of Wnt pathway genes as well as a Wnt-dependent reporter. Finally, chromatin IP experiments demonstrate that β-catenin/TCF-binding directly regulates Fuz expression. These data demonstrate a new model for coordination of Hh and Wnt signaling and reveal a Fuz-dependent negative feedback loop controlling Wnt/β-catenin signaling.
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Affiliation(s)
- Zichao Zhang
- Institute of Biosciences and Technology, Texas A&M Health Science Center, Houston, Texas, United States of America
| | - Bogdan J. Wlodarczyk
- Dell Pediatric Research Institute, University of Texas, Austin, Texas, United States of America
| | - Karen Niederreither
- Dell Pediatric Research Institute, University of Texas, Austin, Texas, United States of America
| | - Shankar Venugopalan
- Institute of Biosciences and Technology, Texas A&M Health Science Center, Houston, Texas, United States of America
| | - Sergio Florez
- Institute of Biosciences and Technology, Texas A&M Health Science Center, Houston, Texas, United States of America
| | - Richard H. Finnell
- Dell Pediatric Research Institute, University of Texas, Austin, Texas, United States of America
| | - Brad A. Amendt
- Institute of Biosciences and Technology, Texas A&M Health Science Center, Houston, Texas, United States of America
- * E-mail:
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15
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Fricke R, Gohl C, Bogdan S. The F-BAR protein family Actin' on the membrane. Commun Integr Biol 2011; 3:89-94. [PMID: 20585497 DOI: 10.4161/cib.3.2.10521] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2009] [Accepted: 11/03/2009] [Indexed: 11/19/2022] Open
Abstract
A tight spatio-temporal coordination of the machineries controlling actin dynamics and membrane remodelling is crucial for a huge variety of cellular processes that shape cells into a multicellular organism. Dynamic membrane remodelling is achieved by a functional relationship between proteins that control plasma membrane curvature, membrane fission and nucleation of new actin filaments. The BAR/F-BAR-domain-containing proteins are prime candidates to couple plasma membrane curvature and actin dynamics in different morphogenetic processes. Here, we discuss recent findings on the membrane-shaping proteins of the F-BAR domain subfamily and how they regulate morphogenetic processes in vivo.
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Affiliation(s)
- Robert Fricke
- Institut für Neurobiologie; Wilhelms-University; Münster; Münster, Germany
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16
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Abstract
In all multicellular organisms, epithelial cells are not only polarized along the apical-basal axis, but also within the epithelial plane, giving cells a sense of direction. Planar cell polarity (PCP) signaling regulates establishment of polarity within the plane of an epithelium. The outcomes of PCP signaling are diverse and include the determination of cell fates, the generation of asymmetric but highly aligned structures, such as the stereocilia in the human inner ear or the hairs on a fly wing, or the directional migration of cells during convergence and extension during vertebrate gastrulation. In humans, aberrant PCP signaling can result in severe developmental defects, such as open neural tubes (spina bifida), and can cause cystic kidneys. In this review, we discuss the basic mechanism and more recent findings of PCP signaling focusing on Drosophila melanogaster, the model organism in which most key PCP components were initially identified.
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Affiliation(s)
- Saw Myat Thanda W Maung
- Department of Developmental and Molecular Biology, Albert Einstein College of Medicine, New York, NY, USA
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17
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Fuz controls the morphogenesis and differentiation of hair follicles through the formation of primary cilia. J Invest Dermatol 2010; 131:302-10. [PMID: 20962855 DOI: 10.1038/jid.2010.306] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Planar cell polarity (PCP) signaling is essential in determining the polarity of cells within the plane of an epithelial sheet. Core PCP genes have been recently shown to control the global polarization of hair follicles in mice. Fuz, a homologue of the Drosophila PCP effector gene, fuzzy, is critical in ciliogenesis in vertebrates, and is required for the development of a wide range of organs in mice. Here, we report that disruption of the Fuz gene in mice severely blocked the development of hair follicles in the skin. In contrast to the loss of hair follicle polarization in mice deficient in core PCP genes, hair follicles in mice lacking the Fuz gene retained their typical anterior-posterior orientation. We show that disruption of Fuz impaired the formation of primary cilia and the hedgehog signaling pathway in the skin. In addition, using skin grafts and skin reconstitution assays we demonstrate that the expression of Fuz is required in both epidermal and dermal cells and that the formation of primary cilia is a cell-autonomous process that does not require cross talk between the epithelia and mesenchymal compartments during hair follicle formation.
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18
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Fischer AH, Zhao C, Li QK, Gustafson KS, Eltoum IE, Tambouret R, Benstein B, Savaloja LC, Kulesza P. The cytologic criteria of malignancy. J Cell Biochem 2010; 110:795-811. [DOI: 10.1002/jcb.22585] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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19
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Wen S, Zhu H, Lu W, Mitchell LE, Shaw GM, Lammer EJ, Finnell RH. Planar cell polarity pathway genes and risk for spina bifida. Am J Med Genet A 2010; 152A:299-304. [PMID: 20101694 DOI: 10.1002/ajmg.a.33230] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Spina bifida, a neural tube closure defect (NTD) involving the posterior portion of what will ultimately give rise to the spinal cord, is one of the most common and serious birth defects. The etiology of spina bifida is thought to be multi-factorial and involve multiple interacting genes and environmental factors. The causes of this congenital malformation remain largely unknown. However, several candidate genes for spina bifida have been identified in lower vertebrates, including the planar cell polarity (PCP) genes. We used data from a case-control study conducted in California to evaluate the association between variation within several key PCP genes and the risk of spina bifida. The PCP genes included in this study were the human homologs of the Xenopus genes Flamingo, Strabismus, Prickle, Dishevelled, and Scrib, two of the homologs of Xenopus Wnt genes, WNT5A and WNT11, and two of the homologs of Xenopus Frizzled, FZD3 and FZD6. None of the 172 SNPs that were evaluated were significantly associated with spina bifida in any racial/ethnic group after correction for multiple testing. However, several SNPs in the PRICKLE2 gene had unadjusted P-value <0.01. In conclusion, our results, though largely negative, suggest that the PRICKLE2 gene may potentially modify the risk of spina bifida and deserves further investigation.
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Affiliation(s)
- Shu Wen
- Baylor College of Medicine, Houston, Texas, USA
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20
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Abstract
Fracture repair is a complex regenerative process initiated in response to injury, resulting in optimal restoration of skeletal function. Although histology characteristics at various phases of fracture repair are clear and well established, much remains to be understood about the process of bone healing, particularly at the molecular signaling level. During the past decade, secreted signaling molecules of the Wnt family have been widely investigated and found to play a central role in controlling embryonic development processes. Wnt signaling pathway also plays a pivotal role in the regulation of bone mass. Recent published data reveal that Wnt signaling pathway is activated during postnatal bone regenerative events, such as ectopic endochondral bone formation and fracture repair. Dysregulation of this pathway greatly inhibits bone formation and healing process. Interestingly, activation of Wnt pathway has potential to improve bone healing, but only utilized after mesenchymal cells have become committed to the osteoblast lineage. These advances suggest an essential role of Wnt pathway in bone regeneration.
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Affiliation(s)
- Yan Chen
- Program in Developmental & Stem Cell Biology, Hospital for Sick Children, University of Toronto, Toronto, Ontario, Canada
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21
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He W, Dai C, Li Y, Zeng G, Monga SP, Liu Y. Wnt/beta-catenin signaling promotes renal interstitial fibrosis. J Am Soc Nephrol 2009; 20:765-76. [PMID: 19297557 DOI: 10.1681/asn.2008060566] [Citation(s) in RCA: 457] [Impact Index Per Article: 30.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Wnts compose a family of signaling proteins that play an essential role in kidney development, but their expression in adult kidney is thought to be silenced. Here, we analyzed the expression and regulation of Wnts and their receptors and antagonists in normal and fibrotic kidneys after obstructive injury. In the normal mouse kidney, the vast majority of 19 different Wnts and 10 frizzled receptor genes was expressed at various levels. After unilateral ureteral obstruction, all members of the Wnt family except Wnt5b, Wnt8b, and Wnt9b were upregulated in the fibrotic kidney with distinct dynamics. In addition, the expression of most Fzd receptors and Wnt antagonists was also induced. Obstructive injury led to a dramatic accumulation of beta-catenin in the cytoplasm and nuclei of renal tubular epithelial cells, indicating activation of the canonical pathway of Wnt signaling. Numerous Wnt/beta-catenin target genes (c-Myc, Twist, lymphoid enhancer-binding factor 1, and fibronectin) were induced, and their expression was closely correlated with renal beta-catenin abundance. Delivery of the Wnt antagonist Dickkopf-1 gene significantly reduced renal beta-catenin accumulation and inhibited the expression of Wnt/beta-catenin target genes. Furthermore, gene therapy with Dickkopf-1 inhibited myofibroblast activation; suppressed expression of fibroblast-specific protein 1, type I collagen, and fibronectin; and reduced total collagen content in the model of obstructive nephropathy. In summary, these results establish a role for Wnt/beta-catenin signaling in the pathogenesis of renal fibrosis and identify this pathway as a potential therapeutic target.
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Affiliation(s)
- Weichun He
- Department of Pathology, University of Pittsburgh, Pittsburgh, Pennsylvania 15261, USA
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22
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Abstract
"Tissue" or "planar" polarity is a characteristic of many epithelial tissues and is not only required for proper cell alignment, but in many instances is absolutely essential for normal function. Planar cell polarity (PCP) is the polarization of cells within the plane of an epithelium in a direction perpendicular to the axis of the apico-basal polarity. The oriented hair alignment in mammalian skin (feather in birds or scales in fish) and highly organized stereocilia bundles in the vertebrate inner ear are examples of such tissue organization. PCP was first described in Drosophila, with non-canonical Wnt signaling (also called PCP signaling, see Chapter 10, Volume 1) shown to be critical for its establishment. Two of the best characterized PCP models in Drosophila are the developing wing and the eye, where the graded activity of the Frizzled (Fz) receptor determines proximo-distal orientation of the wing hairs and mirror-imaged patterning of ommatidia, respectively. In this chapter, we describe simple methods to visualize PCP defects in the Drosophila eye and wing, in both developing and adult tissues. These methods include confocal immunofluorescent analysis of larval or pupal tissues, stained with antibodies specific to PCP components or cytoskeleton markers, and light microscopy of the adult eye and wing.
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23
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Regulation of convergent extension by non-canonical Wnt signaling in the Xenopus embryo. Methods Mol Biol 2008. [PMID: 19109727 DOI: 10.1007/978-1-60327-469-2_30] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
Abstract
Non-canonical Wnt signaling is an important regulator of gastrulation in Xenopus. In particular, it has been implicated in the control of convergent extension movements. Convergent extension in the gastrula occurs primarily in the dorsal tissue of the marginal zone, and explants of this tissue will continue to undergo these movements in isolation. This observation has led to an assay to examine convergent extension movements that is unique to the Xenopus system, and is described herein.
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24
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Torii K, Nishizawa K, Kawasaki A, Yamashita Y, Katada M, Ito M, Nishimoto I, Terashita K, Aiso S, Matsuoka M. Anti-apoptotic action of Wnt5a in dermal fibroblasts is mediated by the PKA signaling pathways. Cell Signal 2008; 20:1256-66. [DOI: 10.1016/j.cellsig.2008.02.013] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2007] [Revised: 02/18/2008] [Accepted: 02/18/2008] [Indexed: 01/22/2023]
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25
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Keller R, Shook D. Dynamic determinations: patterning the cell behaviours that close the amphibian blastopore. Philos Trans R Soc Lond B Biol Sci 2008; 363:1317-32. [PMID: 18192174 DOI: 10.1098/rstb.2007.2250] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
We review the dynamic patterns of cell behaviours in the marginal zone of amphibians with a focus on how the progressive nature and the geometry of these behaviours drive blastopore closure. Mediolateral cell intercalation behaviour and epithelial-mesenchymal transition are used in different combinations in several species of amphibian to generate a conserved pattern of circumblastoporal hoop stresses. Although these cell behaviours are quite different and involve different germ layers and tissue organization, they are expressed in similar patterns. They are expressed progressively along presumptive lateral-medial and anterior-posterior axes of the body plan in highly ordered geometries of functional significance in the context of the biomechanics of blastopore closure, thereby accounting for the production of similar patterns of circumblastoporal forces. It is not the nature of the cell behaviour alone, but the context, the biomechanical connectivity and spatial and temporal pattern of its expression that determine specificity of morphogenic output during gastrulation and blastopore closure. Understanding the patterning of these dynamic features of cell behaviour is important and will require analysis of signalling at much greater spatial and temporal resolution than that has been typical in the analysis of patterning tissue differentiation.
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Affiliation(s)
- Ray Keller
- Department of Biology, University of Virginia, Charlottesville, VA 22904, USA.
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26
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Kohn AD, Moon RT. Wnt and calcium signaling: beta-catenin-independent pathways. Cell Calcium 2008; 38:439-46. [PMID: 16099039 DOI: 10.1016/j.ceca.2005.06.022] [Citation(s) in RCA: 540] [Impact Index Per Article: 33.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2005] [Accepted: 06/28/2005] [Indexed: 12/12/2022]
Abstract
Wnt signaling is a complex pathway in which beta-catenin is typically viewed as a central mediator. However, within the past 15 years, at least three Wnt-mediated pathways have been proposed that function independent of beta-catenin. One pathway involves activation of calcium/calmodulin-dependent kinase II (CamKII) and protein kinase C (PKC). Another includes recruitment of heterotrimeric GTP-binding proteins to activate phospholipase C (PLC) and phosphodiesterase (PDE). Lastly, a pathway similar to the planar cell polarity (PCP) pathway in Drosophila has been identified that activates the Jun-N-terminal kinase (JNK) and, perhaps, small GTP-binding proteins. Calcium has been implicated as an important second messenger in all of these pathways. This review will focus on the role of calcium in Wnt signaling and, as a consequence, provide a limited overview of beta-catenin-independent Wnt signaling.
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Affiliation(s)
- Aimee D Kohn
- Howard Hughes Medical Institute, Division of Hematology, Department of Pharmacology, and the Center for Developmental Biology, University of Washington School of Medicine, Box 357750, Seattle, WA 98195, USA
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27
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Vervenne HBVK, Crombez KRMO, Lambaerts K, Carvalho L, Köppen M, Heisenberg CP, Van de Ven WJM, Petit MMR. Lpp is involved in Wnt/PCP signaling and acts together with Scrib to mediate convergence and extension movements during zebrafish gastrulation. Dev Biol 2008; 320:267-77. [PMID: 18582857 DOI: 10.1016/j.ydbio.2008.05.529] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2007] [Revised: 05/09/2008] [Accepted: 05/09/2008] [Indexed: 01/03/2023]
Abstract
The zyxin-related LPP protein is localized at focal adhesions and cell-cell contacts and is involved in the regulation of smooth muscle cell migration. A known interaction partner of LPP in human is the tumor suppressor protein SCRIB. Knocking down scrib expression during zebrafish embryonic development results in defects of convergence and extension (C&E) movements, which occur during gastrulation and mediate elongation of the anterior-posterior body axis. Mediolateral cell polarization underlying C&E is regulated by a noncanonical Wnt signaling pathway constituting the vertebrate planar cell polarity (PCP) pathway. Here, we investigated the role of Lpp during early zebrafish development. We show that morpholino knockdown of lpp results in defects of C&E, phenocopying noncanonical Wnt signaling mutants. Time-lapse analysis associates the defective dorsal convergence movements with a reduced ability to migrate along straight paths. In addition, expression of Lpp is significantly reduced in Wnt11 morphants and in embryos overexpressing Wnt11 or a dominant-negative form of Rho kinase 2, which is a downstream effector of Wnt11, suggesting that Lpp expression is dependent on noncanonical Wnt signaling. Finally, we demonstrate that Lpp interacts with the PCP protein Scrib in zebrafish, and that Lpp and Scrib cooperate for the mediation of C&E.
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Affiliation(s)
- Hilke B V K Vervenne
- Laboratory for Molecular Oncology, Department of Human Genetics, K.U. Leuven, Leuven, Belgium
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28
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Abstract
Wnt proteins mediate the transduction of at least three major signaling pathways that play central roles in many early and late developmental decisions. They control diverse cellular behaviors, such as cell fate decisions, proliferation, and migration, and are involved in many important embryological events, including axis specification, gastrulation, and limb, heart, or neural development. The three major Wnt pathways are activated by ligands, the Wnts, which clearly belong to the same gene family. However, their signal is then mediated by three separate sets of extracellular, cytoplasmic, and nuclear components that are pathway-specific and that distinguish each of them. Homologs of the Wnt genes and of the Wnt pathways components have been discovered in many eukaryotic model systems and functional investigations have been carried out for most of them. This review extracts available data on the Wnt pathways, from the protist Dictyostelium discoideum to humans, and provides from an evolutionary prospective the overall molecular and functional conservation of the three Wnt pathways and their activators throughout the eukaryotic superkingdom.
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29
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Nambiar RM, Ignatius MS, Henion PD. Zebrafish colgate/hdac1 functions in the non-canonical Wnt pathway during axial extension and in Wnt-independent branchiomotor neuron migration. Mech Dev 2007; 124:682-98. [PMID: 17716875 PMCID: PMC2701655 DOI: 10.1016/j.mod.2007.07.003] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2006] [Revised: 07/02/2007] [Accepted: 07/05/2007] [Indexed: 01/08/2023]
Abstract
Vertebrate gastrulation involves the coordinated movements of populations of cells. These movements include cellular rearrangements in which cells polarize along their medio-lateral axes leading to cell intercalations that result in elongation of the body axis. Molecular analysis of this process has implicated the non-canonical Wnt/Frizzled signaling pathway that is similar to the planar cell polarity pathway (PCP) in Drosophila. Here we describe a zebrafish mutant, colgate (col), which displays defects in the extension of the body axis and the migration of branchiomotor neurons. Activation of the non-canonical Wnt/PCP pathway in these mutant embryos by overexpressing DeltaNdishevelled, rho kinase2 and van gogh-like protein 2 (vangl2) rescues the extension defects suggesting that col acts as a positive regulator of the non-canonical Wnt/PCP pathway. Further, we show that col normally regulates the caudal migration of nVII facial hindbrain branchiomotor neurons and that the mutant phenotype can be rescued by misexpression of vangl2 independent of the Wnt/PCP pathway. We cloned the col locus and found that it encodes histone deacetylase1 (hdac1). Our previous results and studies by others have implicated hdac1 in repressing the canonical Wnt pathway. Here, we demonstrate novel roles for zebrafish hdac1 in activating non-canonical Wnt/PCP signaling underlying axial extension and in promoting Wnt-independent caudal migration of a subset of hindbrain branchiomotor neurons.
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Affiliation(s)
| | | | - Paul D. Henion
- author for correspondence: e-mail: ), Center for Molecular Neurobiology, Ohio State University, 105 Rightmire Hall, 1060 Carmack Rd,. Colombus, OH 43210, Ph 614-292-5111\Fax 614-292-5379
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30
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Chung S, Kim S, Yoon J, Adler PN, Yim J. The balance between the novel protein target of wingless and the Drosophila Rho-associated kinase pathway regulates planar cell polarity in the Drosophila wing. Genetics 2007; 176:891-903. [PMID: 17409077 PMCID: PMC1894616 DOI: 10.1534/genetics.106.069021] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Planar cell polarity (PCP) signaling is mediated by the serpentine receptor Frizzled (Fz) and transduced by Dishevelled (Dsh). Wingless (Wg) signaling utilizes Drosophila Frizzled 2 (DFz2) as a receptor and also requires Dsh for transducing signals to regulate cell proliferation and differentiation in many developmental contexts. Distinct pathways are activated downstream of Dsh in Wg- and Fz-signaling pathways. Recently, a number of genes, which have essential roles as downstream components of PCP signaling, have been identified in Drosophila. They include the small GTPase RhoA/Rho1, its downstream effector Drosophila rho-associated kinase (Drok), and a number of genes such as inturned (in) and fuzzy (fy), whose biochemical functions are unclear. RhoA and Drok provide a link from Fz/Dsh signaling to the modulation of actin cytoskeleton. Here we report the identification of the novel gene target of wingless (tow) by enhancer trap screening. tow expression is negatively regulated by Wg signaling in wing imaginal discs, and the balance between tow and the Drok pathway regulates wing-hair morphogenesis. A loss-of-function mutation in tow does not result in a distinct phenotype. Genetic interaction and gain-of-function studies provide evidence that Tow acts downstream of Fz/Dsh and plays a role in restricting the number of hairs that wing cells form.
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Affiliation(s)
- SeYeon Chung
- School of Biological Sciences, Seoul National University, Seoul 151-742, Korea and Biology Department, University of Virginia, Charlottesville, Virginia 22903
| | - Sangjoon Kim
- School of Biological Sciences, Seoul National University, Seoul 151-742, Korea and Biology Department, University of Virginia, Charlottesville, Virginia 22903
| | - Jeongsook Yoon
- School of Biological Sciences, Seoul National University, Seoul 151-742, Korea and Biology Department, University of Virginia, Charlottesville, Virginia 22903
| | - Paul N. Adler
- School of Biological Sciences, Seoul National University, Seoul 151-742, Korea and Biology Department, University of Virginia, Charlottesville, Virginia 22903
- Corresponding author: Biology Department, Gilmer Hall 245, University of Virginia, Charlottesville, VA 22903. E-mail:
| | - Jeongbin Yim
- School of Biological Sciences, Seoul National University, Seoul 151-742, Korea and Biology Department, University of Virginia, Charlottesville, Virginia 22903
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Doroquez DB, Rebay I. Signal integration during development: mechanisms of EGFR and Notch pathway function and cross-talk. Crit Rev Biochem Mol Biol 2007; 41:339-85. [PMID: 17092823 DOI: 10.1080/10409230600914344] [Citation(s) in RCA: 107] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Metazoan development relies on a highly regulated network of interactions between conserved signal transduction pathways to coordinate all aspects of cell fate specification, differentiation, and growth. In this review, we discuss the intricate interplay between the epidermal growth factor receptor (EGFR; Drosophila EGFR/DER) and the Notch signaling pathways as a paradigm for signal integration during development. First, we describe the current state of understanding of the molecular architecture of the EGFR and Notch signaling pathways that has resulted from synergistic studies in vertebrate, invertebrate, and cultured cell model systems. Then, focusing specifically on the Drosophila eye, we discuss how cooperative, sequential, and antagonistic relationships between these pathways mediate the spatially and temporally regulated processes that generate this sensory organ. The common themes underlying the coordination of the EGFR and Notch pathways appear to be broadly conserved and should, therefore, be directly applicable to elucidating mechanisms of information integration and signaling specificity in vertebrate systems.
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Affiliation(s)
- David B Doroquez
- Department of Biology, Whitehead Institute for Biomedical Research, Massachusetts Institute of Technology, Cambridge, MA, USA
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Zeng G, Awan F, Otruba W, Muller P, Apte U, Tan X, Gandhi C, Demetris AJ, Monga SPS. Wnt'er in liver: expression of Wnt and frizzled genes in mouse. Hepatology 2007; 45:195-204. [PMID: 17187422 DOI: 10.1002/hep.21473] [Citation(s) in RCA: 109] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
UNLABELLED The Wnt signaling pathway is essential for a wide array of developmental and physiological processes. Wnts are extracellular ligands that bind to frizzled (Fz) receptors at the membrane, canonically inducing beta-catenin nuclear translocation and activation. Although beta-catenin has been shown to be critical in liver biology, the expression of the 19 Wnt and 10 Fz genes in liver remains undetermined. We report comprehensive analysis of Wnt and Fz expression in whole liver as well as individual cell types: freshly isolated and plated hepatocytes, biliary epithelial cells, normal and activated stellate and Kupffer cells, and sinusoidal endothelial cells (SECs). Oligonucleotides for the 19 Wnt, 10 frizzled receptors genes, and secreted Frizzled-related protein-1 (sFRP or Fzb) were synthesized based on the available sequences. A total of 11 Wnts and 8 Fz genes and Fzb were expressed in normal liver. Although only 6 Wnt and 5 Fz genes were expressed in freshly isolated hepatocytes, 8 Wnt genes, 7 Fz genes, and Fzb were expressed in plated hepatocytes. Although 12 Wnt and 7 Fz genes were expressed in biliary tree, additional Fz9 and Fzb were only expressed in cultured biliary epithelial cells. The same 14 Wnt and 7 Fz genes were expressed in both activated and normal stellate and Kupffer cells; only Fzb was expressed in their activated state. Also, 11 Wnt, seven Fz, and Fzb genes were expressed in SECs. CONCLUSION These data indicate that most Wnt and frizzled genes are expressed in the liver and might be playing important roles in liver pathobiology via canonical and noncanonical pathways.
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Affiliation(s)
- Gang Zeng
- Department of Pathology, University of Pittsburgh, School of Medicine, Pittsburgh, PA 15261, USA
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Abstract
The fruitfly, Drosophila melanogaster, has been of central importance in analysing the mechanics of cellular processes. Classic forward genetic screens in the fly have identified many of the genes that define critical cell signaling pathways, for example. Our understanding of the Wnt pathway, in particular, has benefited from the many advantages that the fly offers as a model system. Here, I review the history of these discoveries and highlight the utility of the fly in dissecting the molecular workings of Wnt signal transduction.
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Affiliation(s)
- A Bejsovec
- Department of Biology, Duke University, Durham, NC 27708-1000, USA.
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Montcouquiol M, Sans N, Huss D, Kach J, Dickman JD, Forge A, Rachel RA, Copeland NG, Jenkins NA, Bogani D, Murdoch J, Warchol ME, Wenthold RJ, Kelley MW. Asymmetric localization of Vangl2 and Fz3 indicate novel mechanisms for planar cell polarity in mammals. J Neurosci 2006; 26:5265-75. [PMID: 16687519 PMCID: PMC6674235 DOI: 10.1523/jneurosci.4680-05.2006] [Citation(s) in RCA: 253] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Planar cell polarity (PCP) is a process in which cells develop with uniform orientation within the plane of an epithelium. To begin to elucidate the mechanisms of PCP in vertebrates, the localization of the protein Vangl2 (Van Gogh-like) was determined during the development of the mammalian cochlea. Results indicate that Vangl2 becomes asymmetrically localized to specific cell-cell boundaries along the axis of polarization and that this asymmetry is lost in PCP mutants. In addition, PDZ2 (postsynaptic density/Discs large/zona occludens 1), PDZ3, and PDZ4 of the PCP protein Scrb1 (Scribble) are shown to bind to the C-terminal PDZ binding domain of Vangl2, suggesting that Scrb1 plays a direct role in asymmetric targeting of Vangl2. Finally, Fz3 (Frizzled), a newly demonstrated mediator of PCP, is also asymmetrically localized in a pattern that matches that of Vangl2. The presence and asymmetry of Fz3 at the membrane is shown to be dependent on Vangl2. This result suggests a role for Vangl2 in the targeting or anchoring of Fz3, a hypothesis strengthened by the existence of a physical interaction between the two proteins. Together, our data support the idea that protein asymmetry plays an important role in the development of PCP, but the colocalization and interaction of Fz3 and Vangl2 suggests that novel PCP mechanisms exist in vertebrates.
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Affiliation(s)
- Mireille Montcouquiol
- Section on Developmental Neuroscience, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, Maryland 20892, USA.
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Price DJ, Kennedy H, Dehay C, Zhou L, Mercier M, Jossin Y, Goffinet AM, Tissir F, Blakey D, Molnár Z. The development of cortical connections. Eur J Neurosci 2006; 23:910-20. [PMID: 16519656 DOI: 10.1111/j.1460-9568.2006.04620.x] [Citation(s) in RCA: 158] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The cortex receives its major sensory input from the thalamus via thalamocortical axons, and cortical neurons are interconnected in complex networks by corticocortical and callosal axons. Our understanding of the mechanisms generating the circuitry that confers functional properties on cortical neurons and networks, although poor, has been advanced significantly by recent research on the molecular mechanisms of thalamocortical axonal guidance and ordering. Here we review recent advances in knowledge of how thalamocortical axons are guided and how they maintain order during that process. Several studies have shown the importance in this process of guidance molecules including Eph receptors and ephrins, members of the Wnt signalling pathway and members of a novel planar cell polarity pathway. Signalling molecules and transcription factors expressed with graded concentrations across the cortex are important in establishing cortical maps of the topography of sensory surfaces. Neural activity, both spontaneous and evoked, plays a role in refining thalamocortical connections but recent work has indicated that neural activity is less important than was previously thought for the development of some early maps. A strategy used widely in the development of corticocortical and callosal connections is the early overproduction of projections followed by selection after contact with the target structure. Here we discuss recent work in primates indicating that elimination of juvenile projections is not a major mechanism in the development of pathways feeding information forward to higher levels of cortical processing, although its use is common to developing feedback pathways.
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Affiliation(s)
- David J Price
- Centre for Integrative Physiology, Hugh Robson Building, University of Edinburgh, George Square, Edinburgh EH8 9XD, UK.
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Abstract
Atypical cadherin (Celsr3) and the receptor Frizzled3 (Fzd3) are crucial for the development of axonal tracts in the mouse CNS. Celsr3 and Fzd3 are orthologues of the Drosophila'planar cell polarity' (PCP) genes flamingo/starry night (fmi/stan) and frizzled, respectively. Reasoning that Celsr3 and Fzd3 might interact with PCP orthologues in mammals like they do in flies, we used mRNA in situ hybridization to compare the expression of Celsr3 and Fzd3 with that of dishevelled 1, 2 and 3 (Dvl1-3), van gogh-like 1 and 2 (Vangl1, 2), and prickle-like 1 and 2 (Prickle1, 2), during mouse CNS development, from embryonic day 10.5 to postnatal day 21. With the relative exception of Vangl1, all genes were expressed in the developing CNS. Although Celsr3- and Fzd3-deficient mice have similar phenotypes, Fzd3 expression was more widespread than that of Celsr3. Vangl2 and Dvl2 were preferentially expressed in ventricular zones, in keeping with their role during neural tube closure, where they could be partners of Celsr1. Dvl1 had a broad expression, reminiscent of that of Celsr2, and may be involved in neural maintenance. A large overlap in the expression territories of Dvl genes suggested redundancy. Vangl1 and Prickle1 had expression canvases different from each other and from other candidates, indicating unrelated function. Like Celsr3, Dvl3 and Prickle2 were expressed more strongly in postmitotic neurons than in precursors. Thus, the analogy between the PCP and Celsr3-Fzd3 genetic networks is limited, but may include Dvl3 and/or Prickle2.
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Affiliation(s)
- Fadel Tissir
- Developmental Neurobiology Unit, University of Louvain Medical School, 73, Av. E. Mounier, Box DENE7382, B1200 Brussels, Belgium
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Osmont KS, Sadeghian N, Freeling M. Mosaic analysis of extended auricle1 (eta1) suggests that a two-way signaling pathway is involved in positioning the blade/sheath boundary in Zea mays. Dev Biol 2006; 295:1-12. [PMID: 16684518 DOI: 10.1016/j.ydbio.2005.11.012] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2005] [Revised: 10/26/2005] [Accepted: 11/08/2005] [Indexed: 11/19/2022]
Abstract
The maize leaf develops in a simple, stereotypical manner; therefore, it serves as a basic model to understand the processes involved in forming developmental boundaries. extended auricle1 (eta1) is a pleiotropic maize mutant that affects proximodistal leaf development. Mutant eta1 individuals display basipetal displacement of the blade/sheath boundary and the boundary between auricle and blade is not clearly delineated, leading to an undulating auricle. SEM analysis shows that eta1 is required for proper placement of the blade/sheath boundary on the adaxial leaf surface. Examination of vascular and cellular organization indicates that eta1 affects not only placement of the blade/sheath boundary, but also differentiation of cell types within the blade/sheath boundary. Genetic mosaic analysis was used to determine the effect of eta1 mutant tissue on wild-type leaf development and to resolve the site and timing of the Eta1+ gene product. Interestingly, sectors of eta1 tissue affect the placement of the blade/sheath boundary even in wild-type tissue. These results suggest that a two-way signaling pathway may be involved in the positioning of the blade/sheath boundary. Based on these data, we propose a model for Eta1+ function in the maize leaf.
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Affiliation(s)
- Karen S Osmont
- Department of Plant and Microbial Biology, University of California, Berkeley, CA 94720, USA
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Chuai M, Zeng W, Yang X, Boychenko V, Glazier JA, Weijer CJ. Cell movement during chick primitive streak formation. Dev Biol 2006; 296:137-49. [PMID: 16725136 PMCID: PMC2556955 DOI: 10.1016/j.ydbio.2006.04.451] [Citation(s) in RCA: 78] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2005] [Revised: 04/05/2006] [Accepted: 04/07/2006] [Indexed: 10/24/2022]
Abstract
Gastrulation in amniotes begins with extensive re-arrangements of cells in the epiblast resulting in the formation of the primitive streak. We have developed a transfection method that enables us to transfect randomly distributed epiblast cells in the Stage XI-XIII chick blastoderms with GFP fusion proteins. This allows us to use time-lapse microscopy for detailed analysis of the movements and proliferation of epiblast cells during streak formation. Cells in the posterior two thirds of the embryo move in two striking counter-rotating flows that meet at the site of streak formation at the posterior end of the embryo. Cells divide during this rotational movement with a cell cycle time of 6-7 h. Daughter cells remain together, forming small clusters and as result of the flow patterns line up in the streak. Expression of the cyclin-dependent kinase inhibitor, P21/Waf inhibits cell division and severely limits embryo growth, but does not inhibit streak formation or associated flows. To investigate the role off cell-cell intercalation in streak formation we have inhibited the Wnt planar-polarity signalling pathway by expression of a dominant negative Wnt11 and a Dishevelled mutant Xdd1. Both treatments do not result in an inhibition of streak formation, but both severely affect extension of the embryo in later development. Likewise inhibition of myosin II which as been shown to drive cell-cell intercalation during Drosophila germ band extension, has no effect on streak formation, but also effectively blocks elongation after regression has started. These experiments make it unlikely that streak formation involves known cell-cell intercalation mechanisms. Expression of a dominant negative FGFR1c receptor construct as well as the soluble extracellular domain of the FGFR1c receptor both effectively block the cell movements associated with streak formation and mesoderm differentiation, showing the importance of FGF signalling in these processes.
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Affiliation(s)
- Manli Chuai
- Division of Cell and Developmental Biology, Wellcome Trust Biocentre, School of Life Sciences, University of Dundee, Dundee DD1 5EH, UK
| | - Wei Zeng
- Biocomplexity Institute and Department of Physics, Swain Hall West 159, Indiana University, 727 East Third Street, Bloomington, IN 47405-7105, USA
| | - Xuesong Yang
- Division of Cell and Developmental Biology, Wellcome Trust Biocentre, School of Life Sciences, University of Dundee, Dundee DD1 5EH, UK
| | - Veronika Boychenko
- Division of Cell and Developmental Biology, Wellcome Trust Biocentre, School of Life Sciences, University of Dundee, Dundee DD1 5EH, UK
| | - James A. Glazier
- Biocomplexity Institute and Department of Physics, Swain Hall West 159, Indiana University, 727 East Third Street, Bloomington, IN 47405-7105, USA
| | - Cornelis J. Weijer
- Division of Cell and Developmental Biology, Wellcome Trust Biocentre, School of Life Sciences, University of Dundee, Dundee DD1 5EH, UK
- * Corresponding author. Fax: +44 1382 345386. E-mail address: (C.J. Weijer)
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Park TJ, Haigo SL, Wallingford JB. Ciliogenesis defects in embryos lacking inturned or fuzzy function are associated with failure of planar cell polarity and Hedgehog signaling. Nat Genet 2006; 38:303-11. [PMID: 16493421 DOI: 10.1038/ng1753] [Citation(s) in RCA: 303] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2005] [Accepted: 01/23/2006] [Indexed: 01/17/2023]
Abstract
The vertebrate planar cell polarity (PCP) pathway has previously been found to control polarized cell behaviors rather than cell fate. We report here that disruption of Xenopus laevis orthologs of the Drosophila melanogaster PCP effectors inturned (in) or fuzzy (fy) affected not only PCP-dependent convergent extension but also elicited embryonic phenotypes consistent with defective Hedgehog signaling. These defects in Hedgehog signaling resulted from a broad requirement for Inturned and Fuzzy in ciliogenesis. We show that these proteins govern apical actin assembly and thus control the orientation, but not assembly, of ciliary microtubules. Finally, accumulation of Dishevelled and Inturned near the basal apparatus of cilia suggests that these proteins function in a common pathway with core PCP components to regulate ciliogenesis. Together, these data highlight the interrelationships between cell polarity, cellular morphogenesis, signal transduction and cell fate specification.
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Affiliation(s)
- Tae Joo Park
- Department of Molecular Cell and Developmental Biology & Institute for Cellular and Molecular Biology, University of Texas, Austin, Texas 78712, USA
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40
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Dabdoub A, Kelley MW. Planar cell polarity and a potential role for a Wnt morphogen gradient in stereociliary bundle orientation in the mammalian inner ear. ACTA ACUST UNITED AC 2005; 64:446-57. [PMID: 16041762 DOI: 10.1002/neu.20171] [Citation(s) in RCA: 74] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The planar cell polarity (PCP) pathway, a noncanonical Wnt signaling pathway, is crucial for embryonic development in all animals as it is responsible for the regulation of coordinated orientation of structures within the plane of the various epithelia. In the mammalian cochlea, one of the best examples of planar polarity in vertebrates, stereociliary bundles located on mechanosensory hair cells within the sensory epithelium are all uniformly polarized. Generation of this polarity is important for hair cell mechanotransduction and auditory perception as stereociliary bundles are only sensitive to vibrations in their single plane of polarization. We describe the two step developmental process that results in the generation of planar polarity in the mammalian inner ear. Furthermore, we review evidence for the role of Wnt signaling, and the possible generation of a Wnt gradient, in planar polarity.
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Affiliation(s)
- Alain Dabdoub
- Section on Developmental Neuroscience, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, Maryland 20892, USA.
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41
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Lim J, Norga KK, Chen Z, Choi KW. Control of planar cell polarity by interaction of DWnt4 and four-jointed. Genesis 2005; 42:150-61. [PMID: 15986451 DOI: 10.1002/gene.20142] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
The Drosophila eye and the wing display specific planar cell polarity. Although Frizzled (Fz) signaling has been implicated in the establishment of ommatidial and wing hair polarity, evidence for the Wnt gene function has been limited. Here we examined the function of a Drosophila homolog of Wnt4 (DWnt4) in the control of planar polarity. We show that DWnt4 mRNA and protein are preferentially expressed in the ventral region of eye disc. DWnt4 mutant eyes show polarity reversals mostly in the ventral domain, consistent with the ventral expression of DWnt4. Ectopic expression of DWnt4 in the dorsoventral (DV) polar margins is insufficient to induce ommatidial polarity but becomes inductive when coexpressed with Four-jointed (Fj). Similarly, DWnt4 and Fj result in synergistic induction of hair polarity toward the source of expression in the wing. Consistent with genetic interaction, we provide evidence for direct interaction of DWnt4 and Fj transmembrane protein. The extracellular domain of Fj is required for direct binding to DWnt4 and for the induction of hair polarity. In contrast to the synergy between DWnt4 and Fj, DWnt4 antagonizes the polarizing effect of Fz. Our results suggest that DWnt4 is involved in ommatidial polarity signaling in the ventral region of the eye and its function is mediated by interacting with Fj.
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Affiliation(s)
- Janghoo Lim
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX 77030, USA
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42
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Go MJ. Activation of Rac1 or Cdc42 during early morphogenesis of eye discs induces ectopic antennae in Drosophila. Dev Growth Differ 2005; 47:225-31. [PMID: 15921497 DOI: 10.1111/j.1440-169x.2005.00798.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The Rho family small guanosine triphosphatases (GTPases) play important roles in many cellular processes, especially in regulation of cytoskeletal organization. In this study, I examined the functions of Rac1 and Cdc42 for disc morphogenesis in Drosophila. I expressed either a constitutively active form or a dominant negative form of each protein during early morphogenesis of eye discs. Inactivation of Rac1 or Cdc42 resulted in small eye phenotypes. On the other hand, I found that activation of either Rac1 or Cdc42 induces ectopic antennae. In some cases, an almost complete antenna was observed instead of an eye, which was possibly transformation from an eye to an antenna. As a molecular evidence for the ectopic antennae, I found that the Distal-less protein, which is essential for the distalization process, was ectopically induced in the eye discs. I also found that the Decapentaplegic and Wingless proteins, which are upstream morphogenetic signaling proteins of the distalization process, could be ectopically induced by activation of Rac1 or Cdc42. My observations suggest novel functions of Rac1 and Cdc42 for disc morphogenesis.
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Affiliation(s)
- Masahiro J Go
- Department of Developmental Neurobiology, Kumamoto University Graduate School of Medical Sciences, Honjo 1-1-1, Kumamoto 860-8556, Japan.
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Brumby A, Secombe J, Horsfield J, Coombe M, Amin N, Coates D, Saint R, Richardson H. A genetic screen for dominant modifiers of a cyclin E hypomorphic mutation identifies novel regulators of S-phase entry in Drosophila. Genetics 2005; 168:227-51. [PMID: 15454540 PMCID: PMC1448096 DOI: 10.1534/genetics.104.026617] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Cyclin E together with its kinase partner Cdk2 is a critical regulator of entry into S phase. To identify novel genes that regulate the G1- to S-phase transition within a whole animal we made use of a hypomorphic cyclin E mutation, DmcycEJP, which results in a rough eye phenotype. We screened the X and third chromosome deficiencies, tested candidate genes, and carried out a genetic screen of 55,000 EMS or X-ray-mutagenized flies for second or third chromosome mutations that dominantly modified the DmcycEJP rough eye phenotype. We have focused on the DmcycEJP suppressors, S(DmcycEJP), to identify novel negative regulators of S-phase entry. There are 18 suppressor gene groups with more than one allele and several genes that are represented by only a single allele. All S(DmcycEJP) tested suppress the DmcycEJP rough eye phenotype by increasing the number of S phases in the postmorphogenetic furrow S-phase band. By testing candidates we have identified several modifier genes from the mutagenic screen as well as from the deficiency screen. DmcycEJP suppressor genes fall into the classes of: (1) chromatin remodeling or transcription factors; (2) signaling pathways; and (3) cytoskeletal, (4) cell adhesion, and (5) cytoarchitectural tumor suppressors. The cytoarchitectural tumor suppressors include scribble, lethal-2-giant-larvae (lgl), and discs-large (dlg), loss of function of which leads to neoplastic tumors and disruption of apical-basal cell polarity. We further explored the genetic interactions of scribble with S(DmcycEJP) genes and show that hypomorphic scribble mutants exhibit genetic interactions with lgl, scab (alphaPS3-integrin--cell adhesion), phyllopod (signaling), dEB1 (microtubule-binding protein--cytoskeletal), and moira (chromatin remodeling). These interactions of the cytoarchitectural suppressor gene, scribble, with cell adhesion, signaling, cytoskeletal, and chromatin remodeling genes, suggest that these genes may act in a common pathway to negatively regulate cyclin E or S-phase entry.
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Affiliation(s)
- Anthony Brumby
- Peter MacCallum Cancer Centre, East Melbourne, Victoria, 3002, Australia
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Tissir F, Bar I, Jossin Y, De Backer O, Goffinet AM. Protocadherin Celsr3 is crucial in axonal tract development. Nat Neurosci 2005; 8:451-7. [PMID: 15778712 DOI: 10.1038/nn1428] [Citation(s) in RCA: 197] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2005] [Accepted: 03/01/2005] [Indexed: 11/08/2022]
Abstract
In the embryonic CNS, the development of axonal tracts is required for the formation of connections and is regulated by multiple genetic and microenvironmental factors. Here we show that mice with inactivation of Celsr3, an ortholog of Drosophila melanogaster flamingo (fmi; also known as starry night, stan) that encodes a seven-pass protocadherin, have marked, selective anomalies of several major axonal fascicles, implicating protocadherins in axonal development in the mammalian CNS for the first time. In flies, fmi controls planar cell polarity (PCP) in a frizzled-dependent but wingless-independent manner. The neural phenotype in Celsr3 mutant mice is similar to that caused by inactivation of Fzd3, a member of the frizzled family. Celsr3 and Fzd3 are expressed together during brain development and may act in synergy. Thus, a genetic pathway analogous to the one that controls PCP is key in the development of the axonal blueprint.
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Affiliation(s)
- Fadel Tissir
- Developmental Neurobiology Unit, University of Louvain Medical School, 73, avenue Mounier, Box DENE7382, B-1200 Brussels, Belgium
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45
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Wechezak AR, Coan DE. Dvl2 silencing in postdevelopmental cells results in aberrant cell membrane activity and actin disorganization. J Cell Physiol 2005; 202:867-73. [PMID: 15593083 DOI: 10.1002/jcp.20176] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
The upstream events by which endothelial cells perceive the necessity for migration and how this signal results in coordinated movement is unknown. The synchrony underlying these events shares parallels to events occurring during the movement of tissues in embryogenesis. While Wnt signaling is an important pathway in development, components of the cascade exist in postdevelopment endothelial cells. The objective of this study was to determine whether Dishevelled, a key modulation protein in canonical and PCP-CE Wnt signaling was present in endothelium and its potential function. Western blots of cell lysates and immunolabeling studies confirmed that Dishevelled 2 (Dvl2) is an abundant phosphoprotein in endothelial cells. Dvl2 was localized within the cytoplasm of cells as either F-actin-free or F-actin-associated. The disappearance of F-actin-free Dvl2 in vesicle-like organelles and targeting of actin filaments correlated with a loss in cell motility. Gene silencing of Dishevelled by siRNA duplexes resulted in cells with aberrant membrane activity and an inability to extend lamellipodia. Underlying these abnormalities was a disorganization of the actin filament system, including loss of actin-rich densities, indistinct stress fibers and an accompanying increase in diffuse and aggregate cytoplasmic actin. This study represents the first documentation of Dvl2 in postdevelopmental endothelial cells and its possible role in cell migration via manipulation of actin filament bundles.
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Affiliation(s)
- Arlene R Wechezak
- Department of Cell Biology, Hope Heart Institute, Seattle, Washington 98122, USA.
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46
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Chen JA, Voigt J, Gilchrist M, Papalopulu N, Amaya E. Identification of novel genes affecting mesoderm formation and morphogenesis through an enhanced large scale functional screen in Xenopus. Mech Dev 2005; 122:307-31. [PMID: 15763210 DOI: 10.1016/j.mod.2004.11.008] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2004] [Revised: 10/22/2004] [Accepted: 11/13/2004] [Indexed: 10/25/2022]
Abstract
The formation of mesoderm is an important developmental process of vertebrate embryos, which can be broken down into several steps; mesoderm induction, patterning, morphogenesis and differentiation. Although mesoderm formation in Xenopus has been intensively studied, much remains to be learned about the molecular events responsible for each of these steps. Furthermore, the interplay between mesoderm induction, patterning and morphogenesis remains obscure. Here, we describe an enhanced functional screen in Xenopus designed for large-scale identification of genes controlling mesoderm formation. In order to improve the efficiency of the screen, we used a Xenopus tropicalis unique set of cDNAs, highly enriched in full-length clones. The screening strategy incorporates two mesodermal markers, Xbra and Xmyf-5, to assay for cell fate specification and patterning, respectively. In addition we looked for phenotypes that would suggest effects in morphogenesis, such as gastrulation defects and shortened anterior-posterior axis. Out of 1728 full-length clones we isolated 82 for their ability to alter the phenotype of tadpoles and/or the expression of Xbra and Xmyf-5. Many of the clones gave rise to similar misexpression phenotypes (synphenotypes) and many of the genes within each synphenotype group appeared to be involved in similar pathways. We determined the expression pattern of the 82 genes and found that most of the genes were regionalized and expressed in mesoderm. We expect that many of the genes identified in this screen will be important in mesoderm formation.
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Affiliation(s)
- Jun-An Chen
- Wellcome Trust/Cancer Research UK Gurdon Institute, Tennis Court Road, Cambridge CB2 1QN, UK
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Adler PN, Zhu C, Stone D. Inturned localizes to the proximal side of wing cells under the instruction of upstream planar polarity proteins. Curr Biol 2005; 14:2046-51. [PMID: 15556868 DOI: 10.1016/j.cub.2004.11.007] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2004] [Revised: 09/23/2004] [Accepted: 09/23/2004] [Indexed: 10/26/2022]
Abstract
Planar polarity development in the Drosophila wing is under the control of the frizzled (fz) pathway. Recent work has established that the planar polarity (PP) proteins become localized to either the distal, proximal, or both sides of wing cells. Fz and Dsh distal accumulation is thought to locally activate the cytoskeleton to form a hair . Planar polarity effector (PPE) genes such as inturned (in) are not required for the asymmetric accumulation of PP proteins, but they are required for this to influence hair polarity. in mutations result in abnormal hair polarity and are epistatic to mutations in the PP genes. We report that In localizes to the proximal side of wing cells in a PP-dependent and PP-instructive manner. We further show that the function of two other PPE genes (fuzzy and fritz) is essential for In protein localization, a finding consistent with previous genetic data that suggested these three genes function in a common process. These data indicate that accumulation of proteins at the proximal side of wing cells is a key event for the distal activation of the cytoskeleton to form a hair.
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Affiliation(s)
- Paul N Adler
- Biology Department, Morphogenesis and Regenerative Medicine, Institute and Cancer Center, University of Virginia, Charlottesville, Virginia 22903, USA.
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Venema DR, Zeev-Ben-Mordehai T, Auld VJ. Transient apical polarization of Gliotactin and Coracle is required for parallel alignment of wing hairs in Drosophila. Dev Biol 2005; 275:301-14. [PMID: 15501220 DOI: 10.1016/j.ydbio.2004.07.040] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2003] [Revised: 07/12/2004] [Accepted: 07/16/2004] [Indexed: 11/22/2022]
Abstract
In Drosophila, wing hairs are aligned in a distally oriented, parallel array. The frizzled pathway determines proximal-distal cell polarity in the wing; however, in frizzled pathway mutants, wing hairs remain parallel. How wing hairs align has not been determined. We have demonstrated a novel role for the septate junction proteins Gliotactin (Gli) and Coracle (Cora) in this process. Prior to prehair extension, Gli and Cora were restricted to basolateral membranes. During pupal prehair development, Gli and Cora transiently formed apical ribbons oriented from the distal wing tip to the proximal hinge. These ribbons were aligned beneath prehair bases and persisted for several hours. During this time, Gli was lost entirely from the basolateral domain. A Gliotactin mutation altered the apical polarization Gli and Cora and induced defects in hair alignment in pupal and adult stages. Genetic and cell biological assays demonstrated that Gli and Cora function to align hairs independently of frizzled. Taken together, our results indicate that Gli and Cora function as the first-identified members of a long-predicted, frizzled-independent parallel alignment mechanism. We propose a model whereby the apical polarization of Gli and Cora functions to stabilize and align prehairs relative to anterior-posterior cell boundaries during pupal wing development.
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Affiliation(s)
- Dennis R Venema
- Department of Zoology, University of British Columbia, Vancouver, BC, Canada V6T 1Z4
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Abstract
Recent studies have identified Wnt proteins as conserved axon guidance molecules in vertebrates and invertebrates. Wnt proteins are a large family of diffusible factors that play several important roles, both in embryonic development and in adult function. The signaling mechanisms of Wnt proteins are complex and, because Wnts are newly discovered as axon guidance cues, little is known about how Wnt signaling controls the direction of growth cone navigation - a process that is crucial in development of the nervous system. This review summarizes recent work on the role of Wnts in axon guidance and discusses the possible signaling mechanisms involved in growth cone guidance. Understanding how Wnts regulate axon wiring will not only help us to understand how the nervous system is connected but also provide possible tools for axon regeneration.
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Affiliation(s)
- Yimin Zou
- Department of Neurobiology, Pharmacology and Physiology, The University of Chicago, Chicago, IL 60637, USA.
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Abstract
The coordination of epithelial planar polarization is a critical step in the formation of well-ordered tissues. The process has been extensively studied in Drosophila, where genetic analysis has identified a set of "tissue polarity" genes that serve to coordinate planar polarity of cells in the developing wings, bristles and eyes. In the last several years, it has emerged that six of these genes encode junctional proteins. In the wing epithelium, these proteins undergo a polarized redistribution, forming separate proximal and distal cortical domains within each cell. The mechanisms that mediate cortical polarization and cue its direction have been the subject of intense investigation. Cuing the orientation of cortical polarization appears to depend on the atypical Cadherins Fat and Dachsous, although these proteins do not become polarized themselves, nor do they colocalize with components of polarized cortical domains. Interestingly, these Cadherins also act at earlier developmental stages to polarize tissue growth along the proximal-distal axis and it will be interesting to see whether these processes are mechanistically related. Once the axis of polarization is determined, cortical polarity seems to be propagated, at least locally, by a cascade of direct cell-cell interactions mediated by the proximal and distal domains. The cell biological mechanisms leading to polarization are still unclear, but the process depends on the control of Protein Phosphatase 2A activity by its regulatory subunit, Widerborst. Interestingly, Widerborst is found on a planar web of microtubules with connections to apical junctions, suggesting that these microtubules may have an important function in polarizing the cortex.
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Affiliation(s)
- Suzanne Eaton
- Max Planck Institute of Molecular Cell Biology and Genetics, Pfotenhauerstrasse 108, Dresden 01307, Germany.
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