1
|
Characterization and expression of the follistatin-related protein gene in golden pompano Trachinotus ovatus larvae. GENE REPORTS 2020. [DOI: 10.1016/j.genrep.2020.100699] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
|
2
|
Chaly Y, Blair HC, Smith SM, Bushnell DS, Marinov AD, Campfield BT, Hirsch R. Follistatin-like protein 1 regulates chondrocyte proliferation and chondrogenic differentiation of mesenchymal stem cells. Ann Rheum Dis 2014; 74:1467-73. [PMID: 24641944 DOI: 10.1136/annrheumdis-2013-204822] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2013] [Accepted: 03/01/2014] [Indexed: 01/26/2023]
Abstract
OBJECTIVES Chondrocytes, the only cells in the articular cartilage, play a pivotal role in osteoarthritis (OA) because they are responsible for maintenance of the extracellular matrix (ECM). Follistatin-like protein 1 (FSTL1) is a secreted protein found in mesenchymal stem cells (MSCs) and cartilage but whose function is unclear. FSTL1 has been shown to modify cell growth and survival. In this work, we sought to determine whether FSTL1 could regulate chondrogenesis and chondrogenic differentiation of MSCs. METHODS To study the role of FSTL1 in chondrogenesis, we used FSTL1 knockout (KO) mice generated in our laboratory. Proliferative capacity of MSCs, obtained from skulls of E18.5 embryos, was analysed by flow cytometry. Chondrogenic differentiation of MSCs was carried out in a pellet culture system. Gene expression differences were assessed by microarray analysis and real-time PCR. Phosphorylation of Smad3, p38 MAPK and Akt was analysed by western blotting. RESULTS The homozygous FSTL1 KO embryos showed extensive skeletal defects and decreased cellularity in the vertebral cartilage. Cell proliferation of FSTL1-deficient MSCs was reduced. Gene expression analysis in FSTL1 KO MSCs revealed dysregulation of multiple genes important for chondrogenesis. Production of ECM proteoglycans and collagen II expression were decreased in FSTL1-deficient MSCs differentiated into chondrocytes. Transforming growth factor β signalling in FSTL1 KO cells was significantly suppressed. CONCLUSIONS FSTL1 is a potent regulator of chondrocyte proliferation, differentiation and expression of ECM molecules. Our findings may lead to the development of novel strategies for cartilage repair and provide new disease-modifying treatments for OA.
Collapse
Affiliation(s)
- Yury Chaly
- Department of Pediatrics, University of Iowa Carver College of Medicine, Iowa City, Iowa, USA
| | - Harry C Blair
- Department of Pathology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA VA Medical Center, Pittsburgh, Pennsylvania, USA
| | - Sonja M Smith
- Department of Pediatrics, University of Iowa Carver College of Medicine, Iowa City, Iowa, USA
| | - Daniel S Bushnell
- Department of Pediatrics, Children's Hospital of Pittsburgh of UPMC, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Anthony D Marinov
- Department of Pediatrics, Children's Hospital of Pittsburgh of UPMC, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Brian T Campfield
- Department of Pediatrics, Children's Hospital of Pittsburgh of UPMC, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Raphael Hirsch
- Department of Pediatrics, University of Iowa Carver College of Medicine, Iowa City, Iowa, USA
| |
Collapse
|
3
|
Masuda T, Sakuma C, Nagaoka A, Yamagishi T, Ueda S, Nagase T, Yaginuma H. Follistatin-like 5 is expressed in restricted areas of the adult mouse brain: Implications for its function in the olfactory system. Congenit Anom (Kyoto) 2014; 54:63-6. [PMID: 24588779 DOI: 10.1111/cga.12022] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/24/2013] [Accepted: 04/25/2013] [Indexed: 01/13/2023]
Abstract
Follistatin-like 5 (Fstl5), a member of the follistatin family of genes, encodes a secretory glycoprotein. Previous studies revealed that other members of this family including Fstl1 and Fstl3 play an essential role in development, homeostasis, and congenital disorders. However, the in vivo function of Fstl5 is poorly understood. To gain insight into the function of Fstl5 in the mouse central nervous system, we examined the Fstl5 expression pattern in the adult mouse brain. The results of in situ hybridization analysis showed a highly restricted pattern of Fstl5, namely, with localization in the olfactory system, hippocampal CA3 area and granular cell layer of the cerebellum. Restricted expression in the olfactory system suggests a possible role for Fstl5 in maintaining odor perception.
Collapse
Affiliation(s)
- Tomoyuki Masuda
- Department of Histology and Neurobiology, Dokkyo Medical University School of Medicine, Tochigi, Japan
| | | | | | | | | | | | | |
Collapse
|
4
|
Sylva M, Moorman AFM, van den Hoff MJB. Follistatin-like 1 in vertebrate development. ACTA ACUST UNITED AC 2014; 99:61-9. [PMID: 23723173 DOI: 10.1002/bdrc.21030] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2013] [Accepted: 03/08/2013] [Indexed: 11/11/2022]
Abstract
Follistatin-like 1 (Fstl1) is a member of the secreted protein acidic rich in cysteins (SPARC) family and has been implicated in many different signaling pathways, including bone morphogenetic protein (BMP) signaling. In many different developmental processes like, dorso-ventral axis establishment, skeletal, lung and ureter development, loss of function experiments have unveiled an important role for Fstl1. Fstl1 largely functions through inhibiting interactions with the BMP signaling pathway, although, in various disease models, different signaling pathways, like activation of pAKT, pAMPK, Na/K-ATPase, or innate immune responses, are linked to Fstl1. How Fstl1 inhibits BMP signaling remains unclear, although it is known that Fstl1 does not function through a scavenging mechanism, like the other known extracellular BMP inhibitors such as noggin. It has been proposed that Fstl1 interferes with BMP receptor complex formation and as such inhibits propagation of the BMP signal into the cell. Future challenges will encompass the identification of the factors that determine the mechanisms that underlie the fact that Fstl1 acts by interfering with BMP signaling during development, but through other signaling pathways during disease.
Collapse
Affiliation(s)
- M Sylva
- Academic Medical Center, Department of Anatomy, Embryology and Physiology, Meibergdreef 15 1105 AZ, Amsterdam, The Netherlands
| | | | | |
Collapse
|
5
|
Geng Y, Li L, Dong Y, Liu X, Li XH, Ning W. Impaired elastin deposition in Fstl1-/- lung allograft under the renal capsule. PLoS One 2013; 8:e81368. [PMID: 24282586 PMCID: PMC3839892 DOI: 10.1371/journal.pone.0081368] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2013] [Accepted: 10/11/2013] [Indexed: 11/18/2022] Open
Abstract
Lung alveolar development in late gestation is a process important to postnatal survival. Follistatin-like 1 (Fstl1) is a matricellular protein of the Bmp antagonist class, which is involved in the differentiation/maturation of alveolar epithelial cells during saccular stage of lung development. This study investigates the role of Fstl1 on elastin deposition in mesenchyme and subsequent secondary septation in the late gestation stage of terminal saccular formation. To this aim, we modified the renal capsule allograft model for lung organ culture by grafting diced E15.5 distal lung underneath the renal capsule of syngeneic host and cultured up to 7 days. The saccular development of the diced lung allografts, as indicated by the morphology, epithelial and vascular developments, occurred in a manner similar to that in utero. Fstl1 deficiency caused atelectatic phenotype companied by impaired epithelial differentiation in D3 Fstl1−/− lung allografts, which is similar to that of E18.5 Fstl1−/− lungs, supporting the role of Fstl1 during saccular stage. Inhibition of Bmp signaling by intraperitoneal injection of dorsomorphin in the host mice rescued the pulmonary atelectasis of D3 Fstl1−/− allografts. Furthermore, a marked reduction in elastin expression and deposition was observed in walls of air sacs of E18.5 Fstl1−/− lungs and at the tips of the developing alveolar septae of D7 Fstl1−/− allografts. Thus, in addition to its role on alveolar epithelium, Fstl1 is crucial for elastin expression and deposition in mesenchyme during lung alveologenesis. Our data demonstrates that the modified renal capsule allograft model for lung organ culture is a robust and efficient technique to increase our understanding of saccular stage of lung development.
Collapse
Affiliation(s)
- Yan Geng
- College of Life Sciences, Nankai University, Tianjin, China
- School of Pharmaceutical Science, Jiangnan University, Wuxi, China
| | - Lian Li
- College of Life Sciences, Nankai University, Tianjin, China
| | - Yingying Dong
- College of Life Sciences, Nankai University, Tianjin, China
| | - Xue Liu
- College of Life Sciences, Nankai University, Tianjin, China
| | - Xiao-He Li
- College of Life Sciences, Nankai University, Tianjin, China
| | - Wen Ning
- College of Life Sciences, Nankai University, Tianjin, China
- * E-mail:
| |
Collapse
|
6
|
Fstl1 antagonizes BMP signaling and regulates ureter development. PLoS One 2012; 7:e32554. [PMID: 22485132 PMCID: PMC3317656 DOI: 10.1371/journal.pone.0032554] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2011] [Accepted: 02/01/2012] [Indexed: 12/21/2022] Open
Abstract
Bone morphogenetic protein (BMP) signaling pathway plays important roles in urinary tract development although the detailed regulation of its activity in this process remains unclear. Here we report that follistatin-like 1 (Fstl1), encoding a secreted extracellular glycoprotein, is expressed in developing ureter and antagonizes BMP signaling activity. Mouse embryos carrying disrupted Fstl1 gene displayed prominent hydroureter arising from proximal segment and ureterovesical junction defects. These defects were associated with significant reduction in ureteric epithelial cell proliferation at E15.5 and E16.5 as well as absence of subepithelial ureteral mesenchymal cells in the urinary tract at E16.5 and E18.5. At the molecular level, increased BMP signaling was found in Fstl1 deficient ureters, indicated by elevated pSmad1/5/8 activity. In vitro study also indicated that Fstl1 can directly bind to ALK6 which is specifically expressed in ureteric epithelial cells in developing ureter. Furthermore, Sonic hedgehog (SHH) signaling, which is crucial for differentiation of ureteral subepithelial cell proliferation, was also impaired in Fstl1(-/-) ureter. Altogether, our data suggest that Fstl1 is essential in maintaining normal ureter development by antagonizing BMP signaling.
Collapse
|
7
|
Lana-Elola E, Tylzanowski P, Takatalo M, Alakurtti K, Veistinen L, Mitsiadis TA, Graf D, Rice R, Luyten FP, Rice DP. Noggin null allele mice exhibit a microform of holoprosencephaly. Hum Mol Genet 2011; 20:4005-15. [PMID: 21821669 DOI: 10.1093/hmg/ddr329] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
Holoprosencephaly (HPE) is a heterogeneous craniofacial and neural developmental anomaly characterized in its most severe form by the failure of the forebrain to divide. In humans, HPE is associated with disruption of Sonic hedgehog and Nodal signaling pathways, but the role of other signaling pathways has not yet been determined. In this study, we analyzed mice which, due to the lack of the Bmp antagonist Noggin, exhibit elevated Bmp signaling. Noggin(-/-) mice exhibited a solitary median maxillary incisor that developed from a single dental placode, early midfacial narrowing as well as abnormalities in the developing hyoid bone, pituitary gland and vomeronasal organ. In Noggin(-/-) mice, the expression domains of Shh, as well as the Shh target genes Ptch1 and Gli1, were reduced in the frontonasal region at key stages of early facial development. Using E10.5 facial cultures, we show that excessive BMP4 results in reduced Fgf8 and Ptch1 expression. These data suggest that increased Bmp signaling in Noggin(-/-) mice results in downregulation of the hedgehog pathway at a critical stage when the midline craniofacial structures are developing, which leads to a phenotype consistent with a microform of HPE.
Collapse
Affiliation(s)
- Eva Lana-Elola
- Department of Craniofacial Development, King's College, London, UK
| | | | | | | | | | | | | | | | | | | |
Collapse
|
8
|
Sylva M, Li VSW, Buffing AAA, van Es JH, van den Born M, van der Velden S, Gunst Q, Koolstra JH, Moorman AFM, Clevers H, van den Hoff MJB. The BMP antagonist follistatin-like 1 is required for skeletal and lung organogenesis. PLoS One 2011; 6:e22616. [PMID: 21826198 PMCID: PMC3149603 DOI: 10.1371/journal.pone.0022616] [Citation(s) in RCA: 75] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2011] [Accepted: 06/26/2011] [Indexed: 11/19/2022] Open
Abstract
Follistatin-like 1 (Fstl1) is a secreted protein of the BMP inhibitor class. During development, expression of Fstl1 is already found in cleavage stage embryos and becomes gradually restricted to mesenchymal elements of most organs during subsequent development. Knock down experiments in chicken and zebrafish demonstrated a role as a BMP antagonist in early development. To investigate the role of Fstl1 during mouse development, a conditional Fstl1 KO allele as well as a Fstl1-GFP reporter mouse were created. KO mice die at birth from respiratory distress and show multiple defects in lung development. Also, skeletal development is affected. Endochondral bone development, limb patterning as well as patterning of the axial skeleton are perturbed in the absence of Fstl1. Taken together, these observations show that Fstl1 is a crucial regulator in BMP signalling during mouse development.
Collapse
Affiliation(s)
- Marc Sylva
- Heart Failure Research Center, Academic Medical Center, Amsterdam, The Netherlands
| | - Vivian S. W. Li
- Hubrecht Institute, KNAW and University Medical Center, Utrecht, The Netherlands
| | - Anita A. A. Buffing
- Heart Failure Research Center, Academic Medical Center, Amsterdam, The Netherlands
| | - Johan H. van Es
- Hubrecht Institute, KNAW and University Medical Center, Utrecht, The Netherlands
| | - Maaike van den Born
- Hubrecht Institute, KNAW and University Medical Center, Utrecht, The Netherlands
| | | | - Quinn Gunst
- Heart Failure Research Center, Academic Medical Center, Amsterdam, The Netherlands
| | - Jan Harm Koolstra
- Academic Centre of Dentistry Amsterdam (ACTA), Amsterdam, The Netherlands
| | - Antoon F. M. Moorman
- Heart Failure Research Center, Academic Medical Center, Amsterdam, The Netherlands
| | - Hans Clevers
- Hubrecht Institute, KNAW and University Medical Center, Utrecht, The Netherlands
| | | |
Collapse
|
9
|
Nagai H, Lin MC, Sheng G. A modified cornish pasty method for ex ovo culture of the chick embryo. Genesis 2011; 49:46-52. [DOI: 10.1002/dvg.20690] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2010] [Revised: 11/01/2010] [Accepted: 11/03/2010] [Indexed: 11/06/2022]
|
10
|
Adams DC, Karolak MJ, Larman BW, Liaw L, Nolin JD, Oxburgh L. Follistatin-like 1 regulates renal IL-1β expression in cisplatin nephrotoxicity. Am J Physiol Renal Physiol 2010; 299:F1320-7. [PMID: 20861081 DOI: 10.1152/ajprenal.00325.2010] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Follistatin-like 1 (FSTL1) is a secreted protein with homology to both Follistatin and the SPARC/BM40 family of matricellular proteins. In this study, we sought to determine the expression patterns of Fstl1 and its cognate receptor Dip2a in the adult, and to assess the consequences of Fstl1 inactivation on development and homeostasis of the kidney. We find that FSTL1 circulates at high levels in both the human and the mouse and that it is also locally expressed in the loop of Henle in the kidney. To begin to understand the in vivo functions of Fstl1, we generated a mouse mutant using a genetrap approach. The hypomorphic Fstl1 genetrap strain displays a strong reduction in FSTL1 expression at the protein level, but it does not show overt developmental defects. FSTL1 has previously been implicated in diverse disease processes as a regulator of inflammatory cytokine expression, and we therefore evaluated the response of the genetrap strain to cisplatin-mediated acute kidney injury, a disease model with highly cytokine-dependent pathology. We find that although TNF-α and Il6 levels are unchanged relative to wild-type, renal Il-1β expression is increased in genetrap mice following cisplatin treatment. Furthermore, histopatological analysis, expression of the tissue injury marker Havcr1, and measurement of serum creatinine demonstrate that reduction of Fstl1 expression sensitizes the kidney to acute cisplatin nephrotoxicity, suggesting a role for FSTL1-mediated Il-1β suppression in protection of the kidney from acute nephrotoxic injury.
Collapse
Affiliation(s)
- Derek C Adams
- Department of Molecular Medicine, Maine Medical Center Research Institute, Scarborough, Maine 04074, USA
| | | | | | | | | | | |
Collapse
|
11
|
Jonchère V, Réhault-Godbert S, Hennequet-Antier C, Cabau C, Sibut V, Cogburn LA, Nys Y, Gautron J. Gene expression profiling to identify eggshell proteins involved in physical defense of the chicken egg. BMC Genomics 2010; 11:57. [PMID: 20092629 PMCID: PMC2827412 DOI: 10.1186/1471-2164-11-57] [Citation(s) in RCA: 88] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2009] [Accepted: 01/21/2010] [Indexed: 01/17/2023] Open
Abstract
BACKGROUND As uricoletic animals, chickens produce cleidoic eggs, which are self-contained bacteria-resistant biological packages for extra-uterine development of the chick embryo. The eggshell constitutes a natural physical barrier against bacterial penetration if it forms correctly and remains intact. The eggshell's remarkable mechanical properties are due to interactions among mineral components and the organic matrix proteins. The purpose of our study was to identify novel eggshell proteins by examining the transcriptome of the uterus during calcification of the eggshell. An extensive bioinformatic analysis on genes over-expressed in the uterus allowed us to identify novel eggshell proteins that contribute to the egg's natural defenses. RESULTS Our 14 K Del-Mar Chicken Integrated Systems microarray was used for transcriptional profiling in the hen's uterus during eggshell deposition. A total of 605 transcripts were over-expressed in the uterus compared with the magnum or white isthmus across a wide range of abundance (1.1- to 79.4-fold difference). The 605 highly-expressed uterine transcripts correspond to 469 unique genes, which encode 437 different proteins. Gene Ontology (GO) analysis was used for interpretation of protein function. The most over-represented GO terms are related to genes encoding ion transport proteins, which provide eggshell mineral precursors. Signal peptide sequence was found for 54 putative proteins secreted by the uterus during eggshell formation. Many functional proteins are involved in calcium binding or biomineralization--prerequisites for interacting with the mineral phase during eggshell fabrication. While another large group of proteins could be involved in proper folding of the eggshell matrix. Many secreted uterine proteins possess antibacterial properties, which would protect the egg against microbial invasion. A final group includes proteases and protease inhibitors that regulate protein activity in the acellular uterine fluid where eggshell formation takes place. CONCLUSIONS Our original study provides the first detailed description of the chicken uterus transcriptome during formation of the eggshell. We have discovered a cache of about 600 functional genes and identified a large number of encoded proteins secreted into uterine fluid for fabrication of the eggshell and chemical protection of the egg. Some of these uterine genes could prove useful as biological markers for genetic improvement of phenotypic traits (i.e., egg and eggshell quality).
Collapse
Affiliation(s)
| | | | | | - Cédric Cabau
- INRA, UR83 Recherches Avicoles, F-37380 Nouzilly, France
| | - Vonick Sibut
- INRA, UR83 Recherches Avicoles, F-37380 Nouzilly, France
- Institut Technique Avicole, F-37380 Nouzilly, France
| | - Larry A Cogburn
- Department of Animal and Food Sciences, University of Delaware, Newark, DE 19717 USA
| | - Yves Nys
- INRA, UR83 Recherches Avicoles, F-37380 Nouzilly, France
| | - Joel Gautron
- INRA, UR83 Recherches Avicoles, F-37380 Nouzilly, France
| |
Collapse
|
12
|
Wu Y, Zhou S, Smas CM. Downregulated expression of the secreted glycoprotein follistatin-like 1 (Fstl1) is a robust hallmark of preadipocyte to adipocyte conversion. Mech Dev 2010; 127:183-202. [PMID: 20043993 DOI: 10.1016/j.mod.2009.12.003] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2009] [Revised: 12/14/2009] [Accepted: 12/21/2009] [Indexed: 11/20/2022]
Abstract
Obesity is a public health crisis in the United States. Targeting preadipocyte to adipocyte conversion may be an effective approach to regulate adipose mass. Using differential screening we identified Fstl1, a secreted glycoprotein with roles in immunomodulation, cell growth, cardioprotection, and vascularization, as a "preadipokine". Fstl1 is highly expressed in 3T3-L1 preadipocytes and dramatically downregulated early in their differentiation to adipocytes. Northern blot analysis of murine tissues reveals white adipose tissue (WAT), lung and heart as primary sites of Fstl1 transcript expression. In WAT, Fstl1 transcript is restricted to the preadipocyte-containing stromal-vascular cell population. Time course studies in multiple adipogenesis models reveal downregulation of Fstl1 is a hallmark of white and brown adipocyte conversion. By Western blot, we show culture media of 3T3-L1 preadipocytes contains high levels of Fstl1 protein that rapidly decline in adipocyte conversion. Moreover, we observe a correlation between preadipocyte phenotype and Fstl1 expression in that TNFalpha-mediated de-differentiation of 3T3-L1 adipocytes is accompanied by re-expression of Fstl1 transcript and protein. Treatment of 3T3-L1 preadipocytes with a panel of 18 hormones and other agents revealed the demethylating agent 5-aza-cytidine decreases Fstl1 transcript and protein levels by approximately 90%. Furthermore, of 10 additional preadipocyte-expressed genes analyzed we find Pref-1, Col1A1, Sca-1/Ly6a, Lox and Thbs2, are also downregulated by 5-aza-cytidine. Using luciferase reporter constructs containing 791 or 3922 bp of the Fstl1 5' flanking region, we determine negative transcriptional regulation by Kruppel-like factor 15. Together, our data suggest downregulation of Fstl1 expression may be an important feature of preadipocyte to adipocyte conversion.
Collapse
Affiliation(s)
- Yu Wu
- Department of Biochemistry and Cancer Biology, Center for Diabetes and Endocrine Research, University of Toledo College of Medicine, Toledo, OH 43614, USA
| | | | | |
Collapse
|
13
|
Yang Y, Liu J, Mao H, Hu YA, Yan Y, Zhao C. The expression pattern of Follistatin-like 1 in mouse central nervous system development. Gene Expr Patterns 2009; 9:532-40. [PMID: 19595790 DOI: 10.1016/j.gep.2009.07.001] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2009] [Revised: 06/30/2009] [Accepted: 07/02/2009] [Indexed: 10/20/2022]
Abstract
Follistatin-like 1 (Fstl1), also named TSC-36 (TGF-beta-stimulated clone 36), was first cloned from the mouse osteoblastic MC3T3-E1 cell line and can be up-regulated by TGF-beta. To better study the function of Fstl1 during the development of the mouse central nervous system (CNS), we examined Fstl1 expression in the developing mouse CNS, in detail, by in situ hybridization. Our results show that Fstl1 is strongly expressed in the telencephalon, diencephalon, brainstem, limbic system and spinal cord. In the telencephalon, Fstl1 positive cells are mainly located in the ventricular zone (VZ) and the subventricular zone (SVZ); a relatively weak signal was observed in layers II and III of the neocortex at postnatal stages. Fstl1 expression is robust in the developing hippocampus and persists to P20. In the developing diencephalon and hindbrain, abundant Fstl1 signals were also detected in nuclei including the medial habenular nucleus, the medial dorsal nucleus, the cochlear nuclei and so on. In addition, a strong expression of Fstl1 was detected in the thalamencephalic signal center, as well as in the olfactory cortex from E14.5 to P0. Meanwhile, Fstl1 was expressed in the septal area and the cingulate gyrus of the limbic system after birth. A high level of expression was also observed in the ventral horn of the spinal cord. These results indicate that Fstl1 may play an important role during CNS development in the mouse.
Collapse
Affiliation(s)
- Yang Yang
- Key Laboratory of Developmental Genes and Human Diseases, MOE, School of Medicine, Southeast University, 87 Dingjiaoqiao Road, Nanjing, Jiangsu 210009, China
| | | | | | | | | | | |
Collapse
|
14
|
van den Berg G, Somi S, Buffing AAM, Moorman AFM, van den Hoff MJB. Patterns of expression of the Follistatin and Follistatin-like1 genes during chicken heart development: a potential role in valvulogenesis and late heart muscle cell formation. Anat Rec (Hoboken) 2007; 290:783-7. [PMID: 17549728 DOI: 10.1002/ar.20559] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The regulation of concentration and function of growth factors is of crucial importance to proper embryonic development of the heart. The patterns of expression of three extracellular modulators of the transforming growth factor-beta superfamily of growth factors, Follistatin, Follistatin-like1, and Follistatin-like3, are described with respect to heart development. Follistatin is highly localized in the endocardium covering the developing cardiac valves. Follistatin-like1 is localized in the mesenchymal filling of the pharyngeal arches and broadly expressed in cells directly bordering myocardium. Follistatin-like3 is not expressed in the heart. Taken together, these observations are suggestive for a role for Follistatin in cardiac valvulogenesis and a role for Follistatin-like1 in controlling late heart muscle cell formation.
Collapse
Affiliation(s)
- Gert van den Berg
- Heart Failure Research Center, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | | | | | | | | |
Collapse
|
15
|
Li N, Volff JN, Wizenmann A. Rab23 GTPase is expressed asymmetrically in Hensen's node and plays a role in the dorsoventral patterning of the chick neural tube. Dev Dyn 2007; 236:2993-3006. [DOI: 10.1002/dvdy.21331] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
|
16
|
Adams D, Larman B, Oxburgh L. Developmental expression of mouse Follistatin-like 1 (Fstl1): Dynamic regulation during organogenesis of the kidney and lung. Gene Expr Patterns 2006; 7:491-500. [PMID: 17129766 PMCID: PMC4043338 DOI: 10.1016/j.modgep.2006.10.009] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2006] [Revised: 10/17/2006] [Accepted: 10/19/2006] [Indexed: 10/24/2022]
Abstract
Follistatin-like 1 (Fstl1) is a distantly related homolog of the Activin and Bone Morphogenetic Protein antagonist Follistatin. Interestingly, this molecule also has homology with the extracellular matrix modifying protein BM-40/SPARC/osteonectin. Previous studies in chick have identified Fstl1 as a regulator of early mesoderm patterning, somitogenesis, myogenesis and neural development. In this study, we determine the developmental expression pattern of Fstl1 in the mouse. We find that Fstl1 is ubiquitously expressed in the early embryo, and that expression becomes regionalized later during development. In the majority of tissues, Fstl1 is strongly expressed in the mesenchymal component and excluded from the epithelium. Notable exceptions include the central nervous system, in which Fstl1 expression is entirely absent with the exception of the choroid plexi and floor plate, the lung, in which Fstl1 expression can be seen in airway epithelia and the kidney, in which collecting ducts and nascent nephron epithelia express the highest levels of Fstl1.
Collapse
Affiliation(s)
| | | | - Leif Oxburgh
- Corresponding author. Maine Medical Center Research Institute, 81 Research Drive, Scarborough, 04074, ME. , Fax: (207) 885 8110
| |
Collapse
|
17
|
Dal-Pra S, Fürthauer M, Van-Celst J, Thisse B, Thisse C. Noggin1 and Follistatin-like2 function redundantly to Chordin to antagonize BMP activity. Dev Biol 2006; 298:514-26. [PMID: 16890217 DOI: 10.1016/j.ydbio.2006.07.002] [Citation(s) in RCA: 88] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2006] [Revised: 07/06/2006] [Accepted: 07/07/2006] [Indexed: 11/28/2022]
Abstract
In Xenopus, the dorso-ventral (D/V) axis is thought to be specified by the bone morphogenetic proteins (Bmp) activity arising through interaction with antagonists such as Noggin, Chordin and Follistatin. We report here, through inactivation of noggin1 (nog1) that this gene is not essential by itself to establish the D/V patterning. However, at blastula stage, inactivation of nog1 strongly amplifies chordin (chd) phenotype, revealing redundant functions of these two genes on D/V axis formation. Substantial dorsal tissues remaining in the double nog1-chd morphant suggested that other anti-Bmp factors may pattern the D/V axis. We isolated two potential candidates, the follistatin-like (fstl) genes. We found that fstl2 is an early gastrula expressed gene. Its inactivation, similar to nog1, strongly enhances the chd phenotype. Moreover, the penetrance of the ventralization phenotype is much higher when we inactivated simultaneously chd, nog1 and fstl2. Altogether, our data reveal that, while Chordin is the main player of the D/V axis, sufficient to maintain proper activity of Bmp gradient, the structures remaining in the chd mutant (namely dorsal and dorso-lateral territories, in both mesodermal and ectodermal layers) result from the anti-Bmp activity carried by Nog1 and Fstl2 at blastula and gastrula stages.
Collapse
Affiliation(s)
- Sophie Dal-Pra
- Institut de Génétique et de Biologie Moléculaire et Cellulaire, UMR 7104, CNRS/INSERM/ULP, 1 rue Laurent Fries, BP 10142, CU de Strasbourg, 67404 ILLKIRCH Cedex, France
| | | | | | | | | |
Collapse
|
18
|
Zhou J, Liao M, Hatta T, Tanaka M, Xuan X, Fujisaki K. Identification of a follistatin-related protein from the tick Haemaphysalis longicornis and its effect on tick oviposition. Gene 2006; 372:191-8. [PMID: 16517100 DOI: 10.1016/j.gene.2005.12.020] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2005] [Revised: 12/23/2005] [Accepted: 12/27/2005] [Indexed: 11/18/2022]
Abstract
The identification of ovary-associated molecules will lead to a better understanding of the physiology of tick reproduction and vector-pathogen interactions. A gene encoding a follistatin-related protein (FRP) was obtained by random sequencing from the ovary cDNA library of the tick Haemaphysalis longicornis. The full-length cDNA is 1157 bp, including an intact ORF encoding an expected protein with 289 amino acids. Three distinct domains were present in the deduced amino acids, namely, the follistatin-like domain, KAZAL, and two calcium-binding motifs, EFh. The sequence shows homology with the follistatin-related protein (FRP), which was thought to play some roles in the negative regulation of cellular growth. RT-PCR showed that the gene was expressed throughout the developing stages and mainly in the ovary as well as in fat body, hemocytes, salivary glands, and midgut. This gene was expressed in GST-fused recombinant protein with an expected size. The mouse antiserum against the recombinant protein recognized a 56-kDa native protein in both tick ovary and hemolymph. The recombinant proteins were found to have binding activity for both activin A and bone morphogenetic protein-2 (BMP-2). Silencing of FRP by RNAi showed a decrease in tick oviposition, which is consistent with the effect of a recombinant protein vaccine on the adult tick. These results showed that the tick FRP might be involved in tick oviposition. This is the first report of a member of follistatin family proteins in Chelicerata, which include ticks, spiders, and scorpions.
Collapse
Affiliation(s)
- Jinlin Zhou
- National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Obihiro, Hokkaido 080-8555, Japan
| | | | | | | | | | | |
Collapse
|
19
|
Hambrock HO, Kaufmann B, Müller S, Hanisch FG, Nose K, Paulsson M, Maurer P, Hartmann U. Structural characterization of TSC-36/Flik: analysis of two charge isoforms. J Biol Chem 2003; 279:11727-35. [PMID: 14701841 DOI: 10.1074/jbc.m309318200] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Recombinant forms of the glycoprotein TSC-36/Flik were expressed in human cells and used to compare their structural and functional properties with those described for other members of the BM-40/SPARC/osteonectin protein family. TSC-36 was found to occur in two charge isoforms that differ in the extent of sialylation of otherwise identical N-linked, complex type oligosaccharides. Conformational analysis with both circular dichroism and intrinsic fluorescence spectroscopy showed a lack of significant structural changes upon calcium addition or depletion. This finding is in contrast to results obtained for several other BM-40 family members and indicates that the extracellular calcium-binding domain in TSC-36 is non-functional. The lack of conservation of important functional features common to several other members of the BM-40 family indicates that TSC-36, despite its sequence homology to BM-40, has evolved clearly distinct properties.
Collapse
Affiliation(s)
- Harald O Hambrock
- Center for Biochemistry, Medical Faculty, University of Cologne, Joseph-Stelzmann-Strasse 52, D-50931 Cologne, Germany
| | | | | | | | | | | | | | | |
Collapse
|
20
|
Chang C, Eggen BJL, Weinstein DC, Brivanlou AH. Regulation of nodal and BMP signaling by tomoregulin-1 (X7365) through novel mechanisms. Dev Biol 2003; 255:1-11. [PMID: 12618130 DOI: 10.1016/s0012-1606(02)00075-1] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
During early vertebrate development, members of the transforming growth factor beta (TGFbeta) family play important roles in a variety of processes, including germ layer specification, patterning, cell differentiation, migration, and organogenesis. The activities of TGFbetas need to be tightly controlled to ensure their function at the right time and place. Despite identification of multiple regulators of Bone Morphogenetic Protein (BMP) subfamily ligands, modulators of the activin/nodal class of TGFbeta ligands are limited, and include follistatin, Cerberus, and Lefty. Recently, a membrane protein, tomoregulin-1 (TMEFF1, originally named X7365), was isolated and found to contain two follistatin modules in addition to an Epidermal Growth Factor (EGF) domain, suggesting that TMEFF1 may participate in regulation of TGFbeta function. Here, we show that, unlike follistatin and follistatin-related gene (FLRG), TMEFF1 inhibits nodal but not activin in Xenopus. Interestingly, both the follistatin modules and the EGF motif contribute to nodal inhibition. A soluble protein containing the follistatin and the EGF domains, however, is not sufficient for nodal inhibition; the location of TMEFF1 at the membrane is essential for its function. These results suggest that TMEFF1 inhibits nodal through a novel mechanism. TMEFF1 also blocks mesodermal, but not epidermal induction by BMP2. Unlike nodal inhibition, regulation of BMP activities by TMEFF1 requires the latter's cytoplasmic tail, while deletion of either the follistatin modules or the EGF motif does not interfere with the BMP inhibitory function of TMEFF1. These results imply that TMEFF1 may employ different mechanisms in the regulation of nodal and BMP signals. In Xenopus, TMEFF1 is expressed from midgastrula stages onward and is enriched in neural tissue derivatives. This expression pattern suggests that TMEFF1 may modulate nodal and BMP activities during neural patterning. In summary, our data demonstrate that tomoregulin-1 is a novel regulator of nodal and BMP signaling during early vertebrate embryogenesis.
Collapse
Affiliation(s)
- Chenbei Chang
- Laboratory of Vertebrate Molecular Embryology, The Rockefeller University, New York, NY 10021, USA
| | | | | | | |
Collapse
|
21
|
Brown WRA, Hubbard SJ, Tickle C, Wilson SA. The chicken as a model for large-scale analysis of vertebrate gene function. Nat Rev Genet 2003; 4:87-98. [PMID: 12560806 DOI: 10.1038/nrg998] [Citation(s) in RCA: 119] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- William R A Brown
- Institute of Genetics, Nottingham University, Queen's Medical Centre, Nottingham NG7 2UH, UK
| | | | | | | |
Collapse
|
22
|
Vannahme C, Smyth N, Miosge N, Gösling S, Frie C, Paulsson M, Maurer P, Hartmann U. Characterization of SMOC-1, a novel modular calcium-binding protein in basement membranes. J Biol Chem 2002; 277:37977-86. [PMID: 12130637 DOI: 10.1074/jbc.m203830200] [Citation(s) in RCA: 84] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
We have isolated the novel gene SMOC-1 that encodes a secreted modular protein containing an EF-hand calcium-binding domain homologous to that in BM-40. It further consists of two thyroglobulin-like domains, a follistatin-like domain and a novel domain. Recombinant expression in human cells showed that SMOC-1 is a glycoprotein with a calcium-dependent conformation. Results from Northern blots, reverse transcriptase-PCR, and immunoblots revealed a widespread expression in many tissues. Immunofluorescence studies with an antiserum directed against recombinant human SMOC-1 demonstrated a basement membrane localization of the protein and additionally its presence in other extracellular matrices. Immunogold electron microscopy confirmed the localization of SMOC-1 within basement membranes in kidney and skeletal muscle as well as its expression in the zona pellucida surrounding the oocyte.
Collapse
Affiliation(s)
- Christian Vannahme
- Institute for Biochemistry, Medical Faculty, University of Cologne, Joseph-Stelzmann Strasse 52, D-50931 Cologne, Germany
| | | | | | | | | | | | | | | |
Collapse
|
23
|
Gumienny TL, Padgett RW. The other side of TGF-beta superfamily signal regulation: thinking outside the cell. Trends Endocrinol Metab 2002; 13:295-9. [PMID: 12163231 DOI: 10.1016/s1043-2760(02)00615-x] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
The transforming growth factor beta (TGF-beta) superfamily of paracrine and autocrine signaling molecules regulates a vast array of developmental and homeostatic processes and is itself exquisitely regulated. The misregulation of these molecules often results in cancer and other diseases. Here, we focus on new research that explores how TGF-beta superfamily signaling is controlled between the secreting cell and the target cell. Regulation can occur upon ligand secretion (in a latent protein complex) and in the creation of signaling gradients. Proteins in the extracellular milieu sequester ligand away from or facilitate ligand binding to receptor serine kinases. Ligands even positively regulate their own negative regulators. Studies of how TGF-beta signaling is regulated extracellularly have broadened our understanding of TGF-beta pathways, and could provide clues to our understanding and treatment of diseases resulting from misregulation of these pathways.
Collapse
Affiliation(s)
- Tina L Gumienny
- Waksman Institute, Dept Molecular Biology and Biochemistry, and Cancer Institute of New Jersey, Rutgers University, Piscataway, NJ 08854-8020, USA
| | | |
Collapse
|
24
|
Cohen MM, Shiota K. Teratogenesis of holoprosencephaly. AMERICAN JOURNAL OF MEDICAL GENETICS 2002; 109:1-15. [PMID: 11932986 DOI: 10.1002/ajmg.10258] [Citation(s) in RCA: 156] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Teratogenic causes of holoprosencephaly are critically assessed. A brief general review of holoprosencephaly is followed by four tables summarizing etiologic factors. Subjects evaluated here include: 1) maternal diabetes; 2) ethyl alcohol; 3) retinoic acid; 4) mutated genes and teratogens involving the sonic hedgehog signaling network and cholesterol biosynthesis; and 5) cholesterol trafficking, sterol adducts, target tissue response, and sterol sensing domain.
Collapse
Affiliation(s)
- M Michael Cohen
- Department of Oral & Maxillofacial Sciences, Dalhousie University, Halifax, Nova Scotia, Canada.
| | | |
Collapse
|
25
|
Abstract
We performed in vivo experiments in chick embryos that examined whether application of an exogenous source of Shh protein mimics the ability of the notochord to induce ectopic floor plate cells in the neural tube. Shh cannot act alone to induce a floor plate. However, coapplication of Shh and chordin, a BMP antagonist normally coexpressed with Shh in the notochord, results in a marked switch from dorsal to ventral cell fate, including a dramatic and widespread induction of floor plate cells. These data provide in vivo evidence that notochord-derived BMP antagonists may normally generate a permissive environment for the Shh-mediated induction of floor plate. Further experiments performed to address the source of BMPs that are inhibited by the action of chordin suggest that they derive specifically from the surface ectoderm and dorsal-most neuroepithelium. These data indicate that, at neural groove stages, dorsally derived BMPs affect ventral-most regions of the neural plate, suggesting a novel long-range action of BMPs. Together, these studies suggest that the balance of dorsally derived signals and notochord-derived signals determines the extent of floor plate cell induction.
Collapse
Affiliation(s)
- Iain Patten
- Centre for Developmental Genetics, School of Medicine and Biomedical Science, University of Sheffield, S10 2TN, Sheffield, United Kingdom
| | | |
Collapse
|
26
|
Abstract
The aim of this review is to summarize some of the recent advances in molecular embryology that help to explain the pathogenesis of holoprosencephaly (HPE), or its related malformation in model organisms, cyclopia, and laterality defects in humans, derived from detailed analysis of similar malformations in animal models. Recently, defects in several developmental pathways including those operated by the Sonic hedgehog and Nodal signaling factors have been implicated as causes of HPE or laterality defects in humans. Here we summarize the findings in animal models that indicate that both defects can be explained by mechanisms that relate to the proper development of the axial midline in vertebrates. Published 2001 John Wiley & Sons, Inc.
Collapse
Affiliation(s)
- E Roessler
- Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | | |
Collapse
|
27
|
Withington S, Beddington R, Cooke J. Foregut endoderm is required at head process stages for anteriormost neural patterning in chick. Development 2001; 128:309-20. [PMID: 11152630 DOI: 10.1242/dev.128.3.309] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Anterior definitive endoderm, the future pharynx and foregut lining, emerges from the anterior primitive streak and Hensen's node as a cell monolayer that replaces hypoblast during chick gastrulation. At early head process stages (4+ to 6; Hamburger and Hamilton) it lies beneath, lateral to and ahead of the ingressed axial mesoderm. Removal of the monolayer beneath and ahead of the node at stage 4 is followed by normal development, the removed cells being replaced by further ingressing cells from the node. However, similar removal during stages 4+ and 5 results in a permanent window denuded of definitive endoderm, beneath prechordal mesoderm and a variable sector of anterior notochord. The foregut tunnel then fails to form, heart development is confined to separated lateral regions, and the neural tube undergoes no ventral flexures at the normal positions in brain structure. Reduction in forebrain pattern is evident by the 12-somite stage, with most neuraxes lacking telencephalon and eyes, while forebrain expressions of the transcription factor genes GANF and BF1, and of FGF8, are absent or severely reduced. When the foregut endoderm removal is delayed until stage 6, later forebrain pattern appears once again complete, despite lack of foregut formation, of ventral flexure and of heart migration. Important gene expressions within axial mesoderm (chordin, Shh and BMP7) appear unaffected in all embryos, including those due to be pattern-deleted, during the hours following the operation when anterior brain pattern is believed to be determined. A specific system of neural anterior patterning signals, rather than an anterior sector of the initially neurally induced area, is lost following operation. Heterotopic lower layer replacement operations strongly suggest that these patterning signals are positionally specific to anteriormost presumptive foregut. The homeobox gene Hex and the chick Frizbee homologue Crescent are both expressed prominently within anterior definitive endoderm at the time when removal of this tissue results in forebrain defects, and the possible implications of this are discussed. The experiments also demonstrate how stomodeal ectoderm, the tissue that will, much later, form Rathke's pouch and the anterior pituitary, is independently specified by anteriormost lower layer signals at an early stage.
Collapse
Affiliation(s)
- S Withington
- Division of Developmental Neurobiology, National Institute for Medical Research, The Ridgeway, Mill Hill, London NW7 1AA, UK
| | | | | |
Collapse
|
28
|
Liem KF, Jessell TM, Briscoe J. Regulation of the neural patterning activity of sonic hedgehog by secreted BMP inhibitors expressed by notochord and somites. Development 2000; 127:4855-66. [PMID: 11044400 DOI: 10.1242/dev.127.22.4855] [Citation(s) in RCA: 172] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The secretion of Sonic hedgehog (Shh) from the notochord and floor plate appears to generate a ventral-to-dorsal gradient of Shh activity that directs progenitor cell identity and neuronal fate in the ventral neural tube. In principle, the establishment of this Shh activity gradient could be achieved through the graded distribution of the Shh protein itself, or could depend on additional cell surface or secreted proteins that modify the response of neural cells to Shh. Cells of the neural plate differentiate from a region of the ectoderm that has recently expressed high levels of BMPs, raising the possibility that prospective ventral neural cells are exposed to residual levels of BMP activity. We have examined whether modulation of the level of BMP signaling regulates neural cell responses to Shh, and thus might contribute to the patterning of cell types in the ventral neural tube. Using an in vitro assay of neural cell differentiation we show that BMP signaling markedly alters neural cell responses to Shh signals, eliciting a ventral-to-dorsal switch in progenitor cell identity and neuronal fate. BMP signaling is regulated by secreted inhibitory factors, including noggin and follistatin, both of which are expressed in or adjacent to the neural plate. Conversely, follistatin but not noggin produces a dorsal-to-ventral switch in progenitor cell identity and neuronal fate in response to Shh both in vitro and in vivo. These results suggest that the specification of ventral neural cell types depends on the integration of Shh and BMP signaling activities. The net level of BMP signaling within neural tissue may be regulated by follistatin and perhaps other BMP inhibitors secreted by mesodermal cell types that flank the ventral neural tube.
Collapse
Affiliation(s)
- K F Liem
- Howard Hughes Medical Institute, Department of Biochemistry and Molecular Biophysics, Center for Neurobiology and Behavior, Columbia University, New York, NY 10032, USA
| | | | | |
Collapse
|
29
|
Cooke J, Isaac A. Gene interference using antisense oligodeoxynucleotides on whole chick embryos. Optimal ring and roller-bottle culture technique. Mol Biotechnol 2000; 15:259-77. [PMID: 10986702 DOI: 10.1385/mb:15:3:259] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Details are given of an advanced version of the ring method of chick embryo culture. This ensures good development from early blastoderm stages even when the culturing procedure is interrupted by the extended periods required for collecting matched embryo samples and for preparing antisense treatment. Antisense oligodeoxynucleotide treatment, in short-term incubation before return of blastoderms to their ring cultures, is then described. An alternative, roller-bottle, culture method for continued development after treatment is also described. Criteria for the validity and success of this gene interference method are given. While the text is meant to be of detailed practical help to those inexperienced in embryo culture, a preliminary reading, and familiarity with its sectional (Subheading) structure, is recommended before work is undertaken.
Collapse
Affiliation(s)
- J Cooke
- National Institute for Medical Research, London, UK
| | | |
Collapse
|