1
|
Chauhan P, Xue Y, Fisher AL, Kim HS, Babitt JL, Christian JL. The BMP2 prodomain promotes dimerization and cleavage of BMP6 homodimers and BMP2/6 heterodimers in vivo. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.06.19.599755. [PMID: 38948827 PMCID: PMC11212948 DOI: 10.1101/2024.06.19.599755] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/02/2024]
Abstract
Bone morphogenetic protein 2 (BMP2) and BMP6 are key regulators of systemic iron homeostasis. All BMPs are generated as inactive precursor proteins that dimerize and are cleaved to generate the bioactive ligand and inactive prodomain fragments, but nothing is known about how BMP2 or BMP6 homodimeric or heterodimeric precursor proteins are proteolytically activated. Here, we conducted in vitro cleavage assays, which revealed that BMP2 is sequentially cleaved by furin at two sites, initially at a site upstream of the mature ligand, and then at a site adjacent to the ligand domain, while BMP6 is cleaved at a single furin motif. Cleavage of both sites of BMP2 is required to generate fully active BMP2 homodimers when expressed in Xenopus embryos or liver endothelial cells, and fully active BMP2/6 heterodimers in Xenopus . We analyzed BMP activity in Xenopus embryos expressing chimeric proteins consisting of the BMP2 prodomain and BMP6 ligand domain, or vice versa. We show that the prodomain of BMP2 is necessary and sufficient to generate active BMP6 homodimers and BMP2/6 heterodimers, whereas the BMP6 prodomain cannot generate active BMP2 homodimers or BMP2/6 heterodimers. We examined BMP2 and BMP6 homodimeric and heterodimeric ligands generated from native and chimeric precursor proteins expressed in Xenopus embryos. Whereas native BMP6 is not cleaved when expressed alone, it is cleaved to generate BMP2/6 heterodimers when co-expressed with BMP2. Furthermore, BMP2-6 chimeras are cleaved to generate BMP6 homodimers. Our findings reveal an important role for the BMP2 prodomain in dimerization and proteolytic activation of BMP6.
Collapse
|
2
|
McKnite A, Kim HS, Silva J, Christian JL. Lack of evidence that fibrillin1 regulates bone morphogenetic protein 4 activity in kidney or lung. Dev Dyn 2023; 252:761-769. [PMID: 36825302 DOI: 10.1002/dvdy.578] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2022] [Revised: 01/22/2023] [Accepted: 02/05/2023] [Indexed: 02/25/2023] Open
Abstract
BACKGROUND The Bone morphogenetic protein 4 (BMP4) precursor protein is cleaved at two sites to generate an active ligand and inactive prodomain. The ligand and prodomain form a noncovalent complex following the first cleavage, but dissociate after the second cleavage. Transient formation of this complex is essential to generate a stable ligand. Fibrillins (FBNs) bind to the prodomains of BMPs, and can regulate the activity of some ligands. Whether FBNs regulate BMP4 activity is unknown. RESULTS Mice heterozygous for a null allele of Bmp4 showed incompletely penetrant kidney defects and females showed increased mortality between postnatal day 6 and 8. Removal of one copy of Fbn1 did not rescue or enhance kidney defects or lethality. The lungs of Fbn1+/- females had enlarged airspaces that were unchanged in Bmp4+/- ;Fbn1+/- mice. Additionally, removal of one or both alleles of Fbn1 had no effect on steady state levels of BMP4 ligand or on BMP activity in postnatal lungs. CONCLUSIONS These findings do not support the hypothesis that FBN1 plays a role in promoting BMP4 ligand stability or signaling, nor do they support the alternative hypothesis that FBN1 sequesters BMP4 in a latent form, as is the case for other BMP family members.
Collapse
Affiliation(s)
- Autumn McKnite
- Departments of Neurobiology and Internal Medicine, Division of Hematology and Hematologic Malignancies, University of Utah, School of Medicine, Salt Lake City, Utah, USA
| | - Hyung-Seok Kim
- Departments of Neurobiology and Internal Medicine, Division of Hematology and Hematologic Malignancies, University of Utah, School of Medicine, Salt Lake City, Utah, USA
| | - Joshua Silva
- Departments of Neurobiology and Internal Medicine, Division of Hematology and Hematologic Malignancies, University of Utah, School of Medicine, Salt Lake City, Utah, USA
| | - Jan L Christian
- Departments of Neurobiology and Internal Medicine, Division of Hematology and Hematologic Malignancies, University of Utah, School of Medicine, Salt Lake City, Utah, USA
| |
Collapse
|
3
|
Vicidomini R, Serpe M. Local BMP signaling: A sensor for synaptic activity that balances synapse growth and function. Curr Top Dev Biol 2022; 150:211-254. [PMID: 35817503 PMCID: PMC11102767 DOI: 10.1016/bs.ctdb.2022.04.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Synapse development is coordinated by intercellular communication between the pre- and postsynaptic compartments, and by neuronal activity itself. In flies as in vertebrates, neuronal activity induces input-specific changes in the synaptic strength so that the entire circuit maintains stable function in the face of many challenges, including changes in synapse number and strength. But how do neurons sense synapse activity? In several studies carried out using the Drosophila neuromuscular junction (NMJ), we demonstrated that local BMP signaling provides an exquisite sensor for synapse activity. Here we review the main features of this exquisite sensor and discuss its functioning beyond monitoring the synapse activity but rather as a key controller that operates in coordination with other BMP signaling pathways to balance synapse growth, maturation and function.
Collapse
Affiliation(s)
- Rosario Vicidomini
- Neurosciences and Cellular and Structural Biology Division, Eunice Kennedy Shiver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, United States
| | - Mihaela Serpe
- Neurosciences and Cellular and Structural Biology Division, Eunice Kennedy Shiver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, United States.
| |
Collapse
|
4
|
Bottasso-Arias N, Leesman L, Burra K, Snowball J, Shah R, Mohanakrishnan M, Xu Y, Sinner D. BMP4 and Wnt signaling interact to promote mouse tracheal mesenchyme morphogenesis. Am J Physiol Lung Cell Mol Physiol 2022; 322:L224-L242. [PMID: 34851738 PMCID: PMC8794023 DOI: 10.1152/ajplung.00255.2021] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Tracheobronchomalacia and complete tracheal rings are congenital malformations of the trachea associated with morbidity and mortality for which the etiology remains poorly understood. Epithelial expression of Wls (a cargo receptor mediating Wnt ligand secretion) by tracheal cells is essential for patterning the embryonic mouse trachea's cartilage and muscle. RNA sequencing indicated that Wls differentially modulated the expression of BMP signaling molecules. We tested whether BMP signaling, induced by epithelial Wnt ligands, mediates cartilage formation. Deletion of Bmp4 from respiratory tract mesenchyme impaired tracheal cartilage formation that was replaced by ectopic smooth muscle, recapitulating the phenotype observed after epithelial deletion of Wls in the embryonic trachea. Ectopic muscle was caused in part by anomalous differentiation and proliferation of smooth muscle progenitors rather than tracheal cartilage progenitors. Mesenchymal deletion of Bmp4 impaired expression of Wnt/β-catenin target genes, including targets of WNT signaling: Notum and Axin2. In vitro, recombinant (r)BMP4 rescued the expression of Notum in Bmp4-deficient tracheal mesenchymal cells and induced Notum promoter activity via SMAD1/5. RNA sequencing of Bmp4-deficient tracheas identified genes essential for chondrogenesis and muscle development coregulated by BMP and WNT signaling. During tracheal morphogenesis, WNT signaling induces Bmp4 in mesenchymal progenitors to promote cartilage differentiation and restrict trachealis muscle. In turn, Bmp4 differentially regulates the expression of Wnt/β-catenin targets to attenuate mesenchymal WNT signaling and to further support chondrogenesis.
Collapse
Affiliation(s)
- Natalia Bottasso-Arias
- 1Neonatology and Pulmonary Biology Perinatal Institute, Cincinnati Children’s Hospital Medical Center, Cincinnati, Ohio
| | - Lauren Leesman
- 1Neonatology and Pulmonary Biology Perinatal Institute, Cincinnati Children’s Hospital Medical Center, Cincinnati, Ohio
| | - Kaulini Burra
- 1Neonatology and Pulmonary Biology Perinatal Institute, Cincinnati Children’s Hospital Medical Center, Cincinnati, Ohio
| | - John Snowball
- 1Neonatology and Pulmonary Biology Perinatal Institute, Cincinnati Children’s Hospital Medical Center, Cincinnati, Ohio
| | - Ronak Shah
- 1Neonatology and Pulmonary Biology Perinatal Institute, Cincinnati Children’s Hospital Medical Center, Cincinnati, Ohio,2University of Cincinnati Honors Program, Cincinnati, Ohio
| | - Megha Mohanakrishnan
- 1Neonatology and Pulmonary Biology Perinatal Institute, Cincinnati Children’s Hospital Medical Center, Cincinnati, Ohio,2University of Cincinnati Honors Program, Cincinnati, Ohio
| | - Yan Xu
- 1Neonatology and Pulmonary Biology Perinatal Institute, Cincinnati Children’s Hospital Medical Center, Cincinnati, Ohio,3Universtiy of Cincinnati, College of Medicine, Cincinnati, Ohio
| | - Debora Sinner
- 1Neonatology and Pulmonary Biology Perinatal Institute, Cincinnati Children’s Hospital Medical Center, Cincinnati, Ohio,3Universtiy of Cincinnati, College of Medicine, Cincinnati, Ohio
| |
Collapse
|
5
|
Yang D, Yang X, Dai F, Wang Y, Yang Y, Hu M, Cheng Y. The Role of Bone Morphogenetic Protein 4 in Ovarian Function and Diseases. Reprod Sci 2021; 28:3316-3330. [PMID: 33966186 DOI: 10.1007/s43032-021-00600-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2020] [Accepted: 04/22/2021] [Indexed: 12/19/2022]
Abstract
Bone morphogenetic proteins (BMPs) are the largest subfamily of the transforming growth factor-β (TGF-β) superfamily. BMP4 is a secreted protein that was originally identified due to its role in bone and cartilage development. Over the past decades, extensive literature has indicated that BMP4 and its receptors are widely expressed in the ovary. Dysregulation of BMP4 expression may play a vital role in follicular development, polycystic ovary syndrome (PCOS), and ovarian cancer. In this review, we summarized the expression pattern of BMP4 in the ovary, focused on the role of BMP4 in follicular development and steroidogenesis, and discussed the role of BMP4 in ovarian diseases such as polycystic ovary syndrome and ovarian cancer. Some studies have shown that the expression of BMP4 in the ovary is spatiotemporal and species specific, but the effects of BMP4 seem to be similar in follicular development of different species. In addition, BMP4 is involved in the development of hyperandrogenemia in PCOS and drug resistance in ovarian cancer, but further research is still needed to clarify the specific mechanisms.
Collapse
Affiliation(s)
- Dongyong Yang
- Department of Obstetrics and Gynecology, Renmin Hospital of Wuhan University, Wuhan, 430060, China
| | - Xiao Yang
- Department of Obstetrics and Gynecology, Peking University People's Hospital, Beijing, 100044, China
| | - Fangfang Dai
- Department of Obstetrics and Gynecology, Renmin Hospital of Wuhan University, Wuhan, 430060, China
| | - Yanqing Wang
- Department of Obstetrics and Gynecology, Renmin Hospital of Wuhan University, Wuhan, 430060, China
| | - Yi Yang
- School of Physics & Technology, Key Laboratory of Artificial Micro/Nano Structure of Ministry of Education, Wuhan University, Wuhan, 430072, China.
| | - Min Hu
- Department of Obstetrics and Gynecology, Renmin Hospital of Wuhan University, Wuhan, 430060, China.
| | - Yanxiang Cheng
- Department of Obstetrics and Gynecology, Renmin Hospital of Wuhan University, Wuhan, 430060, China.
| |
Collapse
|
6
|
Turner BRH, Itasaki N. Local modulation of the Wnt/β-catenin and bone morphogenic protein (BMP) pathways recapitulates rib defects analogous to cerebro-costo-mandibular syndrome. J Anat 2019; 236:931-945. [PMID: 31884688 DOI: 10.1111/joa.13144] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2019] [Revised: 11/01/2019] [Accepted: 11/28/2019] [Indexed: 12/01/2022] Open
Abstract
Ribs are seldom affected by developmental disorders, however, multiple defects in rib structure are observed in the spliceosomal disease cerebro-costo-mandibular syndrome (CCMS). These defects include rib gaps, found in the posterior part of the costal shaft in multiple ribs, as well as missing ribs, shortened ribs and abnormal costotransverse articulations, which result in inadequate ventilation at birth and high perinatal mortality. The genetic mechanism of CCMS is a loss-of-function mutation in SNRPB, a component of the major spliceosome, and knockdown of this gene in vitro affects the activity of the Wnt/β-catenin and bone morphogenic protein (BMP) pathways. The aim of the present study was to investigate whether altering these pathways in vivo can recapitulate rib gaps and other rib abnormalities in the model animal. Chick embryos were implanted with beads soaked in Wnt/β-catenin and BMP pathway modulators during somitogenesis, and incubated until the ribs were formed. Some embryos were harvested in the preceding days for analysis of the chondrogenic marker Sox9, to determine whether pathway modulation affected somite patterning or chondrogenesis. Wnt/β-catenin inhibition manifested characteristic rib phenotypes seen in CCMS, including rib gaps (P < 0.05) and missing ribs (P < 0.05). BMP pathway activation did not cause rib gaps but yielded missing rib (P < 0.01) and shortened rib phenotypes (P < 0.05). A strong association with vertebral phenotypes was also noted with BMP4 (P < 0.001), including scoliosis (P < 0.05), a feature associated with CCMS. Reduced expression of Sox9 was detected with Wnt/β-catenin inhibition, indicating that inhibition of chondrogenesis precipitated the rib defects in the presence of Wnt/β-catenin inhibitors. BMP pathway activators also reduced Sox9 expression, indicating an interruption of somite patterning in the manifestation of rib defects with BMP4. The present study demonstrates that local inhibition of the Wnt/β-catenin and activation of the BMP pathway can recapitulate rib defects, such as those observed in CCMS. The balance of Wnt/β-catenin and BMP in the somite is vital for correct rib morphogenesis, and alteration of the activity of these two pathways in CCMS may perturb this balance during somite patterning, leading to the observed rib defects.
Collapse
Affiliation(s)
| | - Nobue Itasaki
- Faculty of Health Sciences, University of Bristol, Bristol, UK
| |
Collapse
|
7
|
Dupays L, Towers N, Wood S, David A, Stuckey DJ, Mohun T. Furin, a transcriptional target of NKX2-5, has an essential role in heart development and function. PLoS One 2019; 14:e0212992. [PMID: 30840660 PMCID: PMC6402701 DOI: 10.1371/journal.pone.0212992] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2018] [Accepted: 02/13/2019] [Indexed: 11/22/2022] Open
Abstract
The homeodomain transcription factor NKX2-5 is known to be essential for both normal heart development and for heart function. But little is yet known about the identities of its downstream effectors or their function during differentiation of cardiac progenitor cells (CPCs). We have used transgenic analysis and CRISPR-mediated ablation to identify a cardiac enhancer of the Furin gene. The Furin gene, encoding a proprotein convertase, is directly repressed by NKX2-5. Deletion of Furin in CPCs is embryonic lethal, with mutant hearts showing a range of abnormalities in the outflow tract. Those defects are associated with a reduction in proliferation and premature differentiation of the CPCs. Deletion of Furin in differentiated cardiomyocytes results in viable adult mutant mice showing an elongation of the PR interval, a phenotype that is consistent with the phenotype of mice and human mutant for Nkx2-5. Our results show that Furin mediate some aspects of Nkx2-5 function in the heart.
Collapse
Affiliation(s)
- Laurent Dupays
- The Francis Crick Institute, London, United Kingdom
- * E-mail: (LD); (TM)
| | - Norma Towers
- The Francis Crick Institute, London, United Kingdom
| | - Sophie Wood
- The Francis Crick Institute, London, United Kingdom
| | - Anna David
- Centre for Advanced Biomedical Imaging, University College London, London, United Kingdom
| | - Daniel J. Stuckey
- Centre for Advanced Biomedical Imaging, University College London, London, United Kingdom
| | - Timothy Mohun
- The Francis Crick Institute, London, United Kingdom
- * E-mail: (LD); (TM)
| |
Collapse
|
8
|
Detection of hypomethylation of H19 in a pregnancy with limb-body wall complex. Taiwan J Obstet Gynecol 2019; 57:769-771. [PMID: 30342671 DOI: 10.1016/j.tjog.2018.08.032] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/30/2018] [Indexed: 11/23/2022] Open
|
9
|
Schwarz E. Cystine knot growth factors and their functionally versatile proregions. Biol Chem 2017; 398:1295-1308. [PMID: 28771427 DOI: 10.1515/hsz-2017-0163] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2017] [Accepted: 07/16/2017] [Indexed: 12/23/2022]
Abstract
The cystine knot disulfide pattern has been found to be widespread in nature, since it has been detected in proteins from plants, marine snails, spiders and mammals. Cystine knot proteins are secreted proteins. Their functions range from defense mechanisms as toxins, e.g. ion channel or enzyme inhibitors, to hormones, blood factors and growth factors. Cystine knot proteins can be divided into two superordinate groups. (i) The cystine knot peptides, also referred to - with other non-cystine knot proteins - as knottins, with linear and cyclic polypeptide chains. (ii) The cystine knot growth factor family, which is in the focus of this article. The disulfide ring structure of the cystine knot peptides is made up by the half-cystines 1-4 and 2-5, and the threading disulfide bond is formed by the half-cystines, 3-6. In the growth factor group, the disulfides of half-cystines 1 and 4 pass the ring structure formed by the half-cystines 2-5 and 3-6. In this review, special emphasis will be devoted to the growth factor cystine knot proteins and their proregions. The latter have shifted into the focus of scientific interest as their important biological roles are just to be unravelled.
Collapse
|
10
|
Anderson EN, Wharton KA. Alternative cleavage of the bone morphogenetic protein (BMP), Gbb, produces ligands with distinct developmental functions and receptor preferences. J Biol Chem 2017; 292:19160-19178. [PMID: 28924042 DOI: 10.1074/jbc.m117.793513] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2017] [Revised: 09/14/2017] [Indexed: 12/27/2022] Open
Abstract
The family of TGF-β and bone morphogenetic protein (BMP) signaling proteins has numerous developmental and physiological roles. They are made as proprotein dimers and then cleaved by proprotein convertases to release the C-terminal domain as an active ligand dimer. Multiple proteolytic processing sites in Glass bottom boat (Gbb), the Drosophila BMP7 ortholog, can produce distinct ligand forms. Cleavage at the S1 or atypical S0 site in Gbb produces Gbb15, the conventional small BMP ligand, whereas NS site cleavage produces a larger Gbb38 ligand. We hypothesized that the Gbb prodomain is involved not only in regulating the production of specific ligands but also their signaling output. We found that blocking NS cleavage increased association of the full-length prodomain with Gbb15, resulting in a concomitant decrease in signaling activity. Moreover, NS cleavage was required in vivo for Gbb-Decapentaplegic (Dpp) heterodimer-mediated wing vein patterning but not for Gbb15-Dpp heterodimer activity in cell culture. Gbb NS cleavage was also required for viability through its regulation of pupal ecdysis in a type II receptor Wishful thinking (Wit)-dependent manner. In fact, Gbb38-mediated signaling exhibits a preference for Wit over the other type II receptor Punt. Finally, we discovered that Gbb38 is produced when processing at the S1/S0 site is blocked by O-linked glycosylation in third instar larvae. Our findings demonstrate that BMP prodomain cleavage ensures that the mature ligand is not inhibited by the prodomain. Furthermore, alternative processing of BMP proproteins produces ligands that signal through different receptors and exhibit specific developmental functions.
Collapse
Affiliation(s)
- Edward N Anderson
- From the Department of Molecular Biology, Cell Biology, and Biochemistry, Brown University, Providence, Rhode Island 02912
| | - Kristi A Wharton
- From the Department of Molecular Biology, Cell Biology, and Biochemistry, Brown University, Providence, Rhode Island 02912
| |
Collapse
|
11
|
Modica S, Wolfrum C. The dual role of BMP4 in adipogenesis and metabolism. Adipocyte 2017; 6:141-146. [PMID: 28425843 PMCID: PMC5477726 DOI: 10.1080/21623945.2017.1287637] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/28/2016] [Revised: 01/12/2017] [Accepted: 01/22/2017] [Indexed: 12/13/2022] Open
Abstract
BMP4 has a well-established role in triggering commitment of mesenchymal stem cells into the osteogenic and adipogenic linage. We recently described an additional dual function in adipogenesis: after promoting the formation of both white and brown pre-adipocytes, Bmp4 drives terminal differentiation into mature white rather than brown fat cells. Besides this, Bmp4 seems to have a dual role in metabolism either promoting or repressing oxidative metabolism in a cell context dependent manner.
Collapse
Affiliation(s)
- Salvatore Modica
- a Swiss Federal Institute of Technology, Department of Health Science , Institute of Food Nutrition and Health, Laboratory of Translational Nutrition Biology , Schwerzenbach , Switzerland
| | - Christian Wolfrum
- a Swiss Federal Institute of Technology, Department of Health Science , Institute of Food Nutrition and Health, Laboratory of Translational Nutrition Biology , Schwerzenbach , Switzerland
| |
Collapse
|
12
|
Lopez-Burks ME, Santos R, Kawauchi S, Calof AL, Lander AD. Genetic enhancement of limb defects in a mouse model of Cornelia de Lange syndrome. AMERICAN JOURNAL OF MEDICAL GENETICS PART C-SEMINARS IN MEDICAL GENETICS 2016; 172:146-54. [PMID: 27120109 DOI: 10.1002/ajmg.c.31491] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Cornelia de Lange Syndrome (CdLS) is characterized by a wide variety of structural and functional abnormalities in almost every organ system of the body. CdLS is now known to be caused by mutations that disrupt the function of the cohesin complex or its regulators, and studies of animal models and cell lines tell us that the effect of these mutations is to produce subtle yet pervasive dysregulation of gene expression. With many hundreds of mostly small gene expression changes occurring in every cell type and tissue, identifying the etiology of any particular birth defect is very challenging. Here we focus on limb abnormalities, which are commonly seen in CdLS. In the limb buds of the Nipbl-haploinsufficient mouse (Nipbl(+/-) mouse), a model for the most common form of CdLS, modest gene expression changes are observed in several candidate pathways whose disruption is known to cause limb abnormalities, yet the limbs of Nipbl(+/-) mice develop relatively normally. We hypothesized that further impairment of candidate pathways might produce limb defects similar to those seen in CdLS, and performed genetic experiments to test this. Focusing on Sonic hedgehog (Shh), Bone morphogenetic protein (Bmp), and Hox gene pathways, we show that decreasing Bmp or Hox function (but not Shh function) enhances polydactyly in Nipbl(+/-) mice, and in some cases produces novel skeletal phenotypes. However, frank limb reductions, as are seen in a subset of individuals with CdLS, do not occur, suggesting that additional signaling and/or gene regulatory pathways are involved in producing such dramatic changes. © 2016 Wiley Periodicals, Inc.
Collapse
|
13
|
The prodomain of BMP4 is necessary and sufficient to generate stable BMP4/7 heterodimers with enhanced bioactivity in vivo. Proc Natl Acad Sci U S A 2015; 112:E2307-16. [PMID: 25902523 DOI: 10.1073/pnas.1501449112] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
Bone morphogenetic proteins 4 and 7 (BMP4 and BMP7) are morphogens that signal as either homodimers or heterodimers to regulate embryonic development and adult homeostasis. BMP4/7 heterodimers exhibit markedly higher signaling activity than either homodimer, but the mechanism underlying the enhanced activity is unknown. BMPs are synthesized as inactive precursors that dimerize and are then cleaved to generate both the bioactive ligand and prodomain fragments, which lack signaling activity. Our study reveals a previously unknown requirement for the BMP4 prodomain in promoting heterodimer activity. We show that BMP4 and BMP7 precursor proteins preferentially or exclusively form heterodimers when coexpressed in vivo. In addition, we show that the BMP4 prodomain is both necessary and sufficient for generation of stable heterodimeric ligands with enhanced activity and can enable homodimers to signal in a context in which they normally lack activity. Our results suggest that intrinsic properties of the BMP4 prodomain contribute to the relative bioactivities of homodimers versus heterodimers in vivo. These findings have clinical implications for the use of BMPs as regenerative agents for the treatment of bone injury and disease.
Collapse
|
14
|
Akiyama T, Gibson MC. Morphogen transport: theoretical and experimental controversies. WILEY INTERDISCIPLINARY REVIEWS-DEVELOPMENTAL BIOLOGY 2015; 4:99-112. [PMID: 25581550 DOI: 10.1002/wdev.167] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/02/2014] [Accepted: 10/13/2014] [Indexed: 01/09/2023]
Abstract
UNLABELLED According to morphogen gradient theory, extracellular ligands produced from a localized source convey positional information to receiving cells by signaling in a concentration-dependent manner. How do morphogens create concentration gradients to establish positional information in developing tissues? Surprisingly, the answer to this central question remains largely unknown. During development, a relatively small number of morphogens are reiteratively deployed to ensure normal embryogenesis and organogenesis. Thus, the intracellular processing and extracellular transport of morphogens are tightly regulated in a tissue-specific manner. Over the past few decades, diverse experimental and theoretical approaches have led to numerous conflicting models for gradient formation. In this review, we summarize the experimental evidence for each model and discuss potential future directions for studies of morphogen gradients. For further resources related to this article, please visit the WIREs website. CONFLICT OF INTEREST The authors have declared no conflicts of interest for this article.
Collapse
Affiliation(s)
- Takuya Akiyama
- Stowers Institute for Medical Research, Kansas City, MO, USA
| | | |
Collapse
|
15
|
Tilak A, Nelsen SM, Kim HS, Donley N, McKnite A, Lee H, Christian JL. Simultaneous rather than ordered cleavage of two sites within the BMP4 prodomain leads to loss of ligand in mice. Development 2014; 141:3062-71. [PMID: 24993941 DOI: 10.1242/dev.110130] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
ProBMP4 is generated as a latent precursor that is sequentially cleaved at two sites within the prodomain to generate an active ligand. An initial cleavage occurs adjacent to the ligand domain, which generates a non-covalently associated prodomain/ligand complex that is subsequently dissociated by cleavage at an upstream site. An outstanding question is whether the two sites need to be cleaved sequentially and in the correct order to achieve proper control of BMP4 signaling during development. In the current studies, we demonstrate that mice carrying a knock-in point mutation that causes simultaneous rather than sequential cleavage of both prodomain sites show loss of BMP4 function and die during mid-embryogenesis. Levels of mature BMP4 are severely reduced in mutants, although levels of precursor and cleaved prodomain are unchanged compared with wild type. Our biochemical analysis supports a model in which the transient prodomain/ligand complex that forms during sequential cleavage plays an essential role in prodomain-mediated stabilization of the mature ligand until it can acquire protection from degradation by other means. By contrast, simultaneous cleavage causes premature release of the ligand from the prodomain, leading to destabilization of the ligand and loss of signaling in vivo.
Collapse
Affiliation(s)
- Anup Tilak
- Department of Cell and Developmental Biology, Oregon Health and Sciences University, School of Medicine, Portland, OR 97239-3098, USA
| | - Sylvia M Nelsen
- Department of Cell and Developmental Biology, Oregon Health and Sciences University, School of Medicine, Portland, OR 97239-3098, USA
| | - Hyung-Seok Kim
- Department of Neurobiology and Anatomy and Internal Medicine, Division of Hematology and Hematologic Malignancies, University of Utah, School of Medicine, Salt Lake City, UT 94132, USA
| | - Nathan Donley
- Department of Cell and Developmental Biology, Oregon Health and Sciences University, School of Medicine, Portland, OR 97239-3098, USA
| | - Autumn McKnite
- Department of Neurobiology and Anatomy and Internal Medicine, Division of Hematology and Hematologic Malignancies, University of Utah, School of Medicine, Salt Lake City, UT 94132, USA
| | - Hyunjung Lee
- Department of Cell and Developmental Biology, Oregon Health and Sciences University, School of Medicine, Portland, OR 97239-3098, USA
| | - Jan L Christian
- Department of Neurobiology and Anatomy and Internal Medicine, Division of Hematology and Hematologic Malignancies, University of Utah, School of Medicine, Salt Lake City, UT 94132, USA
| |
Collapse
|
16
|
Zhang YE, Newfeld SJ. Meeting report - TGF-β superfamily: signaling in development and disease. J Cell Sci 2014; 126:4809-13. [PMID: 24172535 DOI: 10.1242/jcs.142398] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
The latest advances on the transforming growth factor β (TGF-β) and bone morphogenetic protein (BMP) signaling pathways were reported at the July 2013 FASEB Summer Research Conference 'The TGF-β Superfamily: Development and Disease'. The meeting was held in Steamboat Springs, Colorado, USA at 6700 feet above sea level in the Rocky Mountains. This was the seventh biannual meeting in the series. In attendance were investigators from a broad range of disciplines with a common interest in the mechanics of TGF-β and BMP signaling pathways, their normal developmental and homeostatic functions, and the diseases associated with pathway misregulation.
Collapse
Affiliation(s)
- Ying E Zhang
- Laboratory of Cellular and Molecular Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | | |
Collapse
|
17
|
Cleavage of the Drosophila screw prodomain is critical for a dynamic BMP morphogen gradient in embryogenesis. Dev Biol 2014; 389:149-59. [PMID: 24560644 DOI: 10.1016/j.ydbio.2014.02.007] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2013] [Revised: 01/31/2014] [Accepted: 02/12/2014] [Indexed: 12/22/2022]
Abstract
Dorsoventral patterning of the Drosophila embryo is regulated by graded distribution of bone morphogenetic proteins (BMPs) composed of two ligands, decapentaplegic (Dpp) a BMP2/4 ortholog and screw (Scw) a BMP5/6/7/8 family member. scw(E1) encodes an unusual allele that was isolated as a dominant enhancer of partial loss-of-function mutations in dpp. However, the molecular mechanisms that underlie this genetic interaction remain to be addressed. Here we show that scw(E1) contains a mutation at the furin cleavage site within the prodomain that is crucial for ligand production. Furthermore, our data show that Scw(E1) preferentially forms heterodimers with Dpp rather than homotypic dimers, providing a possible explanation for the dominant negative phenotype of scw(E1) alleles. The unprocessed prodomain of Scw(E1) remains in a complex with the Dpp:Scw heterodimer, and thus could interfere with interaction of the ligand with the extracellular matrix, or the kinetics of processing/secretion of the ligand in vivo. These data reveal novel mechanisms by which post-translational regulation of Scw can modulate Dpp signaling activity.
Collapse
|
18
|
Constam DB. Regulation of TGFβ and related signals by precursor processing. Semin Cell Dev Biol 2014; 32:85-97. [PMID: 24508081 DOI: 10.1016/j.semcdb.2014.01.008] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2014] [Accepted: 01/29/2014] [Indexed: 10/25/2022]
Abstract
Secreted cytokines of the TGFβ family are found in all multicellular organisms and implicated in regulating fundamental cell behaviors such as proliferation, differentiation, migration and survival. Signal transduction involves complexes of specific type I and II receptor kinases that induce the nuclear translocation of Smad transcription factors to regulate target genes. Ligands of the BMP and Nodal subgroups act at a distance to specify distinct cell fates in a concentration-dependent manner. These signaling gradients are shaped by multiple factors, including proteases of the proprotein convertase (PC) family that hydrolyze one or several peptide bonds between an N-terminal prodomain and the C-terminal domain that forms the mature ligand. This review summarizes information on the proteolytic processing of TGFβ and related precursors, and its spatiotemporal regulation by PCs during development and various diseases, including cancer. Available evidence suggests that the unmasking of receptor binding epitopes of TGFβ is only one (and in some cases a non-essential) function of precursor processing. Future studies should consider the impact of proteolytic maturation on protein localization, trafficking and turnover in cells and in the extracellular space.
Collapse
Affiliation(s)
- Daniel B Constam
- Ecole Polytechnique Fédérale de Lausanne (EPFL), Bâtiment SV ISREC, Station 19, CH-1015 Lausanne, Switzerland.
| |
Collapse
|
19
|
Yamawaki K, Ueda S, Okada T, Oshima T, Kakitani M, Kato T, Tomizuka K. Adult-specific systemic over-expression reveals novel in vivo effects of the soluble forms of ActRIIA, ActRIIB and BMPRII. PLoS One 2013; 8:e78076. [PMID: 24205096 PMCID: PMC3804470 DOI: 10.1371/journal.pone.0078076] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2013] [Accepted: 09/16/2013] [Indexed: 12/21/2022] Open
Abstract
Bone morphogenetic proteins (BMPs)/growth differentiation factors (GDFs), which belong to the TGF-beta superfamily, are pleiotropic factors that play a role in regulating the embryonic development and postnatal homeostasis of various organs and tissues by controlling cellular differentiation, proliferation and apoptosis. Conventional transgenic and knockout (KO) mouse approaches have provided only limited information regarding the in vivo functions of BMP signaling in adult animals due to the effects on prenatal development and the difficulty in manipulating multiligand signals simultaneously. We recently produced transgenic chimeric mice(Tg chimeras) in which the soluble IgG1-Fc fusion protein of three BMP type II receptors (ActRIIA, ActRIIB, BMPRII) was highly circulated (281-709 μg/ml), specifically in adult mouse blood. Since each BMP receptor can bind to multiple BMP ligands, these Tg chimeras should be useful to investigate the effects of trapping multiple BMP ligands. Remarkably, some phenotypes were unexpected based on previous studies, such as KO mouse analyses, presumably representing the effects of the multiple ligand trapping. These phenotypes included increased red blood cells (RBCs) and decreased viability in adults. In a further study, we focused on the phenotype of increased RBCs and found that extramedullary hematopoiesis in the spleen, not in the bone marrow, was increased using histological and flow cytometric analyses. Although it remains to be elucidated whether the transgene products affect the tissues directly or indirectly, our data provide novel and important insight into the biological functions of the soluble IgG1-Fc fusion protein of three BMP type II receptors in adults, and our approach should have broad applications to research on other ligand receptor families and studies involving mouse models.
Collapse
Affiliation(s)
- Kengo Yamawaki
- Biologics Research Laboratories, Kyowa Hakko Kirin Co., Ltd, Machida-shi, Tokyo, Japan
- * E-mail: (KY); (KT)
| | - Shinobu Ueda
- Comprehensive Research Organization, Institute for Innovation Design, Waseda University, Shinjuku-ku, Tokyo, Japan
| | - Tsutomu Okada
- Biologics Research Laboratories, Kyowa Hakko Kirin Co., Ltd, Machida-shi, Tokyo, Japan
| | - Takeshi Oshima
- Biologics Research Laboratories, Kyowa Hakko Kirin Co., Ltd, Machida-shi, Tokyo, Japan
| | - Makoto Kakitani
- Biologics Research Laboratories, Kyowa Hakko Kirin Co., Ltd, Machida-shi, Tokyo, Japan
| | - Takashi Kato
- Department of Biology, School of Education, Waseda University, Shinjuku-ku, Tokyo, Japan
| | - Kazuma Tomizuka
- Kyowa Hakko Kirin California, Inc., La Jolla, San Diego, California, United States of America
- * E-mail: (KY); (KT)
| |
Collapse
|
20
|
Fine-tuned shuttles for bone morphogenetic proteins. Curr Opin Genet Dev 2013; 23:374-84. [PMID: 23735641 DOI: 10.1016/j.gde.2013.04.012] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2013] [Revised: 04/15/2013] [Accepted: 04/16/2013] [Indexed: 01/27/2023]
Abstract
Bone morphogenetic proteins (BMPs) are potent secreted signaling factors that trigger phosphorylation of Smad transcriptional regulators through receptor complex binding at the cell-surface. Resulting changes in target gene expression impact critical cellular responses during development and tissue homeostasis. BMP activity is tightly regulated in time and space by secreted modulators that control BMP extracellular distribution and availability for receptor binding. Such extracellular regulation is key for BMPs to function as morphogens and/or in the formation of morphogen activity gradients. Here, we review shuttling systems utilized to control the distribution of BMP ligands in tissue of various geometries, developing under different temporal constraints. We discuss the biological advantages for employing specific strategies for BMP shuttling and roles of varied ligand forms.
Collapse
|
21
|
Huang Y, Lu Y, Mues G, Wang S, Bonds J, D'Souza R. Functional evaluation of a novel tooth agenesis-associated bone morphogenetic protein 4 prodomain mutation. Eur J Oral Sci 2013; 121:313-8. [PMID: 23841782 DOI: 10.1111/eos.12055] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/11/2013] [Indexed: 11/28/2022]
Abstract
The detection of gene mutations in patients with congenitally missing teeth is not very complicated; however, proving causality is often quite difficult. Here, we report the detection of a substitution mutation, A42P, within the prodomain of bone morphogenetic protein 4 (BMP4) in a small family with tooth agenesis and describe a functional alteration that may be responsible for the tooth phenotype. As BMP4 is essential for the development of teeth and also for many other organs, it would be of considerable interest to find a BMP4 mutation that is associated only with tooth agenesis. Our in vitro investigations revealed that the A42P mutation neither affected processing and secretion of BMP4 nor altered functional properties, such as the induction of alkaline phosphatase or signaling through Smad1/5/8 phosphorylation by the mature BMP4 ligand. However, immunofluorescence staining revealed that the prodomains of BMP4 which harbor the A42P substitution form fibrillar structures around transfected cells in culture and that this fibrillar network is significantly decreased when mutant prodomains are expressed. Our finding suggests that in vivo, BMP4 prodomain behavior might also be altered by the mutation and could influence storage or transport of mature BMP4 in the extracellular matrix of the developing tooth.
Collapse
Affiliation(s)
- Yanyu Huang
- The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST), Key Laboratory of Oral Biomedicine, Ministry of Education, School & Hospital of Stomatology, Wuhan University, Wuhan, China
| | | | | | | | | | | |
Collapse
|
22
|
Vaze D, Hombalkar NN, Dhandore P. Gastroschisis with ceco-appendicular agenesis: a novel presentation. Congenit Anom (Kyoto) 2012; 52:182-3. [PMID: 22925221 DOI: 10.1111/j.1741-4520.2011.00343.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
Abstract
Gastroschisis is associated with intestinal atresia and malrotation. A few cases have been reported of appendicular agenesis associated with gastroschisis. No previous case has been reported of cecal agenesis with gastroschisis in the literature. As cecal agenesis is a very rare anomaly, its concomitant presentation with gastroschisis is extremely rare. We report a case of gastroschisis associated with ceco-appendicular agenesis. The possible embryological explanation for the presentation is discussed.
Collapse
Affiliation(s)
- Dhananjay Vaze
- Department of Surgery, Government Medical College, Miraj, Maharashtra, India.
| | | | | |
Collapse
|
23
|
Zhou AJ, Zhu Z, Clokie CML, Peel SAF. Mutation of a cleavage site adjacent to the mature domain leads to increase in secreted mature BMP-2 with reduced activity. Growth Factors 2012; 30:267-75. [PMID: 22583106 DOI: 10.3109/08977194.2012.686497] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Proteolytic cleavage of precursor bone morphogenetic protein (proBMP) is an important step in generating the active mature BMP. ProBMP-2 contains two proprotein convertase (PC) recognition sites (S1 and S2) and is postulated to be cleaved by PCs at those sites. Cell lines expressing proBMP-2, with a silenced S1 site (mS1) that inhibited PC cleavage, secreted the 20-kDa form BMP-2, while cells expressing wild type (wt) BMP-2 secreted 18- and 20-kDa mature BMP-2 N-terminal isoforms. The mS1 cells secreted 15-fold more mature BMP-2 than the wt, despite their similar mRNA levels. Mutant-secreted BMP-2 demonstrated biological activity in vitro; however, its activity was reduced compared with wt. These data demonstrate that proBMP-2 can be cleaved at an alternative cleavage site without prior S1 site cleavage in cell lines overexpressing BMP-2 and more importantly suggest that the presence of the 2-kDa linker peptide can affect activity and secretion of the mature protein.
Collapse
Affiliation(s)
- Aileen J Zhou
- Oral & Maxillofacial Surgery, University of Toronto, Toronto, ON, Canada
| | | | | | | |
Collapse
|
24
|
Ramel MC, Hill CS. Spatial regulation of BMP activity. FEBS Lett 2012; 586:1929-41. [PMID: 22710177 DOI: 10.1016/j.febslet.2012.02.035] [Citation(s) in RCA: 67] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2012] [Revised: 02/21/2012] [Accepted: 02/22/2012] [Indexed: 12/14/2022]
Abstract
The bone morphogenetic protein (BMP) signalling pathway is critical for embryonic development and tissue homeostasis, and impaired BMP signalling has been implicated in multiple diseases. Molecular tools have been developed to visualise BMP activity in vivo and these have allowed a better understanding of the intricate ways in which BMP activity is regulated spatially. In particular, generation and interpretation of BMP activity gradients during development result from the complex interplay between core BMP signalling components and specific regulators. In this essay we discuss the mechanisms by which spatial regulation of BMP activity is achieved and its functional consequences.
Collapse
Affiliation(s)
- Marie-Christine Ramel
- Laboratory of Developmental Signalling, Cancer Research UK London Research Institute, 44 Lincoln's Inn Fields, London WC2A 3LY, United Kingdom
| | | |
Collapse
|
25
|
Loss of endothelial furin leads to cardiac malformation and early postnatal death. Mol Cell Biol 2012; 32:3382-91. [PMID: 22733989 DOI: 10.1128/mcb.06331-11] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
In mammals, seven proprotein convertases (PCs) cleave secretory proteins after basic residues, and four of them are called furin-like PCs: furin, PC5, PACE4, and PC7. In vitro, they share many substrates. However, furin is essential during development since deficient embryos die at embryonic day 11 and exhibit multiple developmental defects, particularly defects related to the function of endothelial cells. To define the role of furin in endothelial cells, an endothelial cell-specific knockout (ecKO) of the Furin gene was generated. Newborns die shortly after birth, indicating that furin is essential in these cells. Magnetic resonance imaging revealed that ecKO embryos exhibit ventricular septal defects (VSD) and/or valve malformations. In addition, primary cultures of wild-type and ecKO lung endothelial cells revealed that ecKO cells are unable to grow. Growth was efficiently rescued by extracellular soluble furin. Analysis of the processing of precursors of endothelin-1 (ET-1), adrenomedullin (Adm), transforming growth factor β1 (TGF-β1), and bone morphogenetic protein 4 (BMP4) confirmed that ET-1, Adm, and TGF-β1 are in vivo substrates of endothelial furin. Mature ET-1 and BMP4 forms were reduced by ~90% in ecKO purified endothelial cells from lungs.
Collapse
|
26
|
Abstract
Signaling molecules of the transforming growth factor (TGF)-β family are generated from proprotein precursors containing prodomain sequences that are typically removed to allow signaling by the mature ligands. A form of a TGF-β family ligand that remains covalently attached to its prodomain but retains signaling activity has been identified. Glass bottom boat (Gbb), a Drosophila homolog of the bone morphogenetic protein 5/6/7/8 subfamily, is active as a carboxyl-terminal fragment of the proprotein (Gbb15) that is generated by a conventional processing event common to TGF-β ligands. Unexpectedly, a larger form (Gbb38) produced by processing at a newly identified furin site in the prodomain is also secreted and active. Contrary to the present paradigm in which TGF-β ligands require dissociation of the entire prodomain for activity, Gbb38 is active in cell culture and in vivo without additional processing at conventional sites. The large form can restore the viability of gbb mutant animals but has distinct signaling properties compared with the conventional form. Production of multiple functional ligands from one proprotein is a potential mechanism to fine-tune TGF-β signaling outputs. Mutations in TGF-β family members have been linked to human diseases, several of which affect potential furin cleavage sites in prodomains. However, given the diversity of potential furin processing sites and prodomain functions, direct experimentation will be required to determine whether production of active jumbo ligands is a general feature of TGF-β superfamily members.
Collapse
Affiliation(s)
- Aidan J Peterson
- Department of Genetics, Cell Biology and Development, University of Minnesota, Minneapolis, MN 55455, USA
| | | |
Collapse
|
27
|
Akiyama T, Marqués G, Wharton KA. A large bioactive BMP ligand with distinct signaling properties is produced by alternative proconvertase processing. Sci Signal 2012; 5:ra28. [PMID: 22472650 DOI: 10.1126/scisignal.2002549] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Dimers of conventional transforming growth factor-β (TGF-β) and bone morphogenetic protein (BMP) ligands are composed of two 100- to 140-amino acid peptides that are produced through the proteolytic processing of a proprotein precursor by proconvertases, such as furin. We report the identification of an evolutionarily conserved furin processing site in the amino terminus (NS) of the Glass bottom boat (Gbb; the Drosophila ortholog of vertebrate BMP5, 6, and 7) proprotein that generates a 328-amino acid, active BMP ligand distinct from the conventional 130-amino acid ligand. Gbb38, the large ligand form of Gbb, exhibited greater signaling activity and a longer range than the shorter form Gbb15. The abundance of Gbb15 and Gbb38 varied among different tissues, raising the possibility that differential processing could account for tissue-specific behaviors of BMPs. In human populations, mutations that abolished the NS cleavage site in BMP4, BMP15, or anti-Müllerian hormone were associated with cleft lip with or without cleft palate (BMP4), premature ovarian failure (BMP15), and persistent Müllerian duct syndrome (anti-Müllerian hormone), suggesting the importance of NS processing during development. The identification of this large BMP ligand form and the functional differences between large and small ligands exemplifies the potential for differential proprotein processing to substantially affect BMP and TGF-β signaling output in different tissue and cellular contexts.
Collapse
Affiliation(s)
- Takuya Akiyama
- Department of Molecular Biology, Cell Biology, and Biochemistry, Brown University, Providence, RI 02912, USA
| | | | | |
Collapse
|
28
|
Cathepsin H indirectly regulates morphogenetic protein-4 (BMP-4) in various human cell lines. Radiol Oncol 2011; 45:259-66. [PMID: 22933963 PMCID: PMC3423750 DOI: 10.2478/v10019-011-0034-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2011] [Accepted: 09/13/2011] [Indexed: 11/23/2022] Open
Abstract
Background Cathepsin H is a cysteine protease considered to play a major role in tumor progression, however, its precise function in tumorigenesis is unclear. Cathepsin H was recently proposed to be involved in processing of bone morphogenetic protein 4 (BMP-4) in mice. In order to clarify whether cathepsin H also regulates BMP-4 in humans, its impact on BMP-4 expression, processing and degradation was investigated in prostate cancer (PC-3), osteosarcoma (HOS) and pro-monocytic (U937) human cell lines. Materials and methods BMP-4 expression was founded to be regulated by cathepsin H using PCR array technology and confirmed by real time PCR. Immunoassays including Western blot and confocal microscopy were used to evaluate the influence of cathepsin H on BMP-4 processing. Results In contrast to HOS, the expression of BMP-4 mRNA in U937 and PC3 cells was significantly decreased by cathepsin H. The different regulation of BMP-4 synthesis could be associated with the absence of the mature 28 kDa cathepsin H form in HOS cells, where only the intermediate 30 kDa form was observed. No co-localization of BMP-4 and cathepsin H was observed in human cell lines and the multistep processing of BMP-4 was not altered in the presence of specific cathepsin H inhibitor. Isolated cathepsin H does not cleave mature recombinant BMP-4, neither with its amino- nor its endopeptidase activity. Conclusions Our results exclude direct proteolytic processing of BMP-4 by cathepsin H, however, they provide support for its involvement in the regulation of BMP-4 expression.
Collapse
|
29
|
Harrison CA, Al-Musawi SL, Walton KL. Prodomains regulate the synthesis, extracellular localisation and activity of TGF-β superfamily ligands. Growth Factors 2011; 29:174-86. [PMID: 21864080 DOI: 10.3109/08977194.2011.608666] [Citation(s) in RCA: 86] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
All transforming growth factor-β (TGF-β) ligands are synthesised as precursor molecules consisting of a signal peptide, an N-terminal prodomain and a C-terminal mature domain. During synthesis, prodomains interact non-covalently with mature domains, maintaining the molecules in a conformation competent for dimerisation. Dimeric precursors are cleaved by proprotein convertases, and TGF-β ligands are secreted from the cell non-covalently associated with their prodomains. Extracellularly, prodomains localise TGF-β ligands within the vicinity of their target cells via interactions with extracellular matrix proteins, including fibrillin and perlecan. For some family members (TGF-β1, TGF-β2, TGF-β3, myostatin, GDF-11 and BMP-10), prodomains bind with high enough affinity to suppress biological activity. The subsequent mechanism of activation of these latent TGF-β ligands varies according to cell type and context, but all activating mechanisms directly target prodomains. Thus, prodomains control many aspects of TGF-β superfamily biology, and alterations in prodomain function are often associated with disease.
Collapse
Affiliation(s)
- Craig A Harrison
- Prince Henry's Institute of Medical Research, Clayton, VIC 3168, Australia.
| | | | | |
Collapse
|
30
|
Kwon S, Christian JL. Sortilin associates with transforming growth factor-beta family proteins to enhance lysosome-mediated degradation. J Biol Chem 2011; 286:21876-85. [PMID: 21521695 PMCID: PMC3122242 DOI: 10.1074/jbc.m111.228262] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2010] [Revised: 04/15/2011] [Indexed: 01/17/2023] Open
Abstract
Transforming growth factor (TGF)-β family proteins are synthesized as precursors that are cleaved to generate an active ligand. Previous studies suggest that TGF-β activity can be controlled by lysosomal degradation of both precursor proteins and ligands, but how these soluble proteins are trafficked to the lysosome is incompletely understood. The current studies show that sortilin selectively co-immunoprecipitates with the cleaved prodomain and/or precursor form of TGF-β family members. Furthermore, sortilin co-localizes with, and enhances accumulation of a nodal family member in the Golgi. Co-expression of sortilin with TGF-β family members leads to decreased accumulation of precursor proteins and cleavage products and this is attenuated by lysosomal, but not proteosomal inhibitors. In Xenopus embryos, overexpression of sortilin leads to a decrease in phospho-Smad2 levels and phenocopies loss of nodal signaling. Conversely, down-regulation of sortilin expression in HeLa cells leads to an up-regulation of endogenous bone morphogenic protein pathway activation, as indicated by an increase in phospho-Smad1/5/8 levels. Our results suggest that sortilin negatively regulates TGF-β signaling by diverting trafficking of precursor proteins to the lysosome during transit through the biosynthetic pathway.
Collapse
Affiliation(s)
- Sunjong Kwon
- From the Department of Cell and Developmental Biology, Oregon Health & Science University, Portland, Oregon 97239
| | - Jan L. Christian
- From the Department of Cell and Developmental Biology, Oregon Health & Science University, Portland, Oregon 97239
| |
Collapse
|
31
|
Susan-Resiga D, Essalmani R, Hamelin J, Asselin MC, Benjannet S, Chamberland A, Day R, Szumska D, Constam D, Bhattacharya S, Prat A, Seidah NG. Furin is the major processing enzyme of the cardiac-specific growth factor bone morphogenetic protein 10. J Biol Chem 2011; 286:22785-94. [PMID: 21550985 DOI: 10.1074/jbc.m111.233577] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Bone morphogenetic protein 10 (BMP10) is a member of the TGF-β superfamily and plays a critical role in heart development. In the postnatal heart, BMP10 is restricted to the right atrium. The inactive pro-BMP10 (∼60 kDa) is processed into active BMP10 (∼14 kDa) by an unknown protease. Proteolytic cleavage occurs at the RIRR(316)↓ site (human), suggesting the involvement of proprotein convertase(s) (PCs). In vitro digestion of a 12-mer peptide encompassing the predicted cleavage site with furin, PACE4, PC5/6, and PC7, showed that furin cleaves the best, whereas PC7 is inactive on this peptide. Ex vivo studies in COS-1 cells, a cell line lacking PC5/6, revealed efficient processing of pro-BMP10 by endogenous PCs other than PC5/6. The lack of processing of overexpressed pro-BMP10 in the furin- and PACE4-deficient cell line, CHO-FD11, and in furin-deficient LoVo cells, was restored by stable (CHO-FD11/Fur cells) or transient (LoVo cells) expression of furin. Use of cell-permeable and cell surface inhibitors suggested that endogenous PCs process pro-BMP10 mostly intracellularly, but also at the cell surface. Ex vivo experiments in mouse primary hepatocytes (wild type, PC5/6 knock-out, and furin knock-out) corroborated the above findings that pro-BMP10 is a substrate for endogenous furin. Western blot analyses of heart right atria extracts from wild type and PACE4 knock-out adult mice showed no significant difference in the processing of pro-BMP10, implying no in vivo role of PACE4. Overall, our in vitro, ex vivo, and in vivo data suggest that furin is the major convertase responsible for the generation of BMP10.
Collapse
Affiliation(s)
- Delia Susan-Resiga
- Laboratory of Biochemical Neuroendocrinology, Clinical Research Institute of Montreal, Université de Montréal, Montreal, Quebec H2W 1R7, Canada
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
32
|
Matsumaru D, Haraguchi R, Miyagawa S, Motoyama J, Nakagata N, Meijlink F, Yamada G. Genetic analysis of Hedgehog signaling in ventral body wall development and the onset of omphalocele formation. PLoS One 2011; 6:e16260. [PMID: 21283718 PMCID: PMC3024424 DOI: 10.1371/journal.pone.0016260] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2010] [Accepted: 12/12/2010] [Indexed: 01/03/2023] Open
Abstract
Background An omphalocele is one of the major ventral body wall malformations and
is characterized by abnormally herniated viscera from the body trunk. It has
been frequently found to be associated with other structural malformations,
such as genitourinary malformations and digit abnormalities. In spite of its
clinical importance, the etiology of omphalocele formation is still controversial.
Hedgehog (Hh) signaling is one of the essential growth factor signaling pathways
involved in the formation of the limbs and urogenital system. However, the
relationship between Hh signaling and ventral body wall formation remains
unclear. Methodology/Principal Findings To gain insight into the roles of Hh signaling in ventral body wall formation
and its malformation, we analyzed phenotypes of mouse mutants of Sonic
hedgehog (Shh), GLI-Kruppel family member
3 (Gli3) and Aristaless-like homeobox 4
(Alx4). Introduction of additional Alx4Lst
mutations into the Gli3Xt/Xt background resulted
in various degrees of severe omphalocele and pubic diastasis. In addition,
loss of a single Shh allele restored the omphalocele and
pubic symphysis of Gli3Xt/+; Alx4Lst/Lst
embryos. We also observed ectopic Hh activity in the ventral body wall region
of Gli3Xt/Xt embryos. Moreover, tamoxifen-inducible
gain-of-function experiments to induce ectopic Hh signaling revealed Hh signal
dose-dependent formation of omphaloceles. Conclusions/Significance We suggest that one of the possible causes of omphalocele and pubic diastasis
is ectopically-induced Hh signaling. To our knowledge, this would be the first
demonstration of the involvement of Hh signaling in ventral body wall malformation
and the genetic rescue of omphalocele phenotypes.
Collapse
Affiliation(s)
- Daisuke Matsumaru
- Global COE "Cell Fate Regulation
Research and Education Unit", Department of Organ Formation, Institute of
Molecular Embryology and Genetics (IMEG), Kumamoto University, Kumamoto, Japan
| | - Ryuma Haraguchi
- Global COE "Cell Fate Regulation
Research and Education Unit", Department of Organ Formation, Institute of
Molecular Embryology and Genetics (IMEG), Kumamoto University, Kumamoto, Japan
| | - Shinichi Miyagawa
- Global COE "Cell Fate Regulation
Research and Education Unit", Department of Organ Formation, Institute of
Molecular Embryology and Genetics (IMEG), Kumamoto University, Kumamoto, Japan
| | - Jun Motoyama
- Department of Medical Life Systems,
Doshisha University, Kyoto, Japan
| | - Naomi Nakagata
- Center for Animal Resources and
Development (CARD), Kumamoto University, Kumamoto, Japan
| | - Frits Meijlink
- Hubrecht Institute, KNAW and University
Medical Center, Utrecht, The Netherlands
| | - Gen Yamada
- Global COE "Cell Fate Regulation
Research and Education Unit", Department of Organ Formation, Institute of
Molecular Embryology and Genetics (IMEG), Kumamoto University, Kumamoto, Japan
- * E-mail:
| |
Collapse
|
33
|
Bone morphogenetic proteins: a critical review. Cell Signal 2010; 23:609-20. [PMID: 20959140 DOI: 10.1016/j.cellsig.2010.10.003] [Citation(s) in RCA: 486] [Impact Index Per Article: 34.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2010] [Revised: 09/14/2010] [Accepted: 10/01/2010] [Indexed: 12/14/2022]
Abstract
Bone Morphogenetic Proteins (BMPs) are potent growth factors belonging to the Transforming Growth Factor Beta superfamily. To date over 20 members have been identified in humans with varying functions during processes such as embryogenesis, skeletal formation, hematopoiesis and neurogenesis. Though their functions have been identified, less is known regarding levels of regulation at the extracellular matrix, membrane surface, and receptor activation. Further, current models of activation lack the integration of these regulatory mechanisms. This review focuses on the different levels of regulation, ranging from the release of BMPs into the extracellular components to receptor activation for different BMPs. It also highlights areas in research that is lacking or contradictory.
Collapse
|
34
|
Abstract
Genetic and functional studies indicate that common components of the bone morphogenetic protein (BMP) signaling pathway play critical roles in regulating vascular development in the embryo and in promoting vascular homeostasis and disease in the adult. However, discrepancies between in vitro and in vivo findings and distinct functional properties of the BMP signaling pathway in different vascular beds, have led to controversies in the field that have been difficult to reconcile. This review attempts to clarify some of these issues by providing an up to date overview of the biology and genetics of BMP signaling relevant to the intact vasculature.
Collapse
|
35
|
Sopory S, Kwon S, Wehrli M, Christian JL. Regulation of Dpp activity by tissue-specific cleavage of an upstream site within the prodomain. Dev Biol 2010; 346:102-12. [PMID: 20659445 DOI: 10.1016/j.ydbio.2010.07.019] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2009] [Revised: 07/11/2010] [Accepted: 07/17/2010] [Indexed: 12/20/2022]
Abstract
BMP4 is synthesized as an inactive precursor that is cleaved at two sites during maturation: initially at a site (S1) adjacent to the ligand domain, and then at an upstream site (S2) within the prodomain. Cleavage at the second site regulates the stability of mature BMP4 and this in turn influences its signaling intensity and range of action. The Drosophila ortholog of BMP4, Dpp, functions as a long- or short-range signaling molecule in the wing disc or embryonic midgut, respectively but mechanisms that differentially regulate its bioactivity in these tissues have not been explored. In the current studies we demonstrate, by dpp mutant rescue, that cleavage at the S2 site of proDpp is required for development of the wing and leg imaginal discs, whereas cleavage at the S1 site is sufficient to rescue Dpp function in the midgut. Both the S1 and S2 sites of proDpp are cleaved in the wing disc, and S2-cleavage is essential to generate sufficient ligand to exceed the threshold for pMAD activation at both short- and long-range in most cells. By contrast, proDpp is cleaved at the S1 site alone in the embryonic mesoderm and this generates sufficient ligand to activate physiological target genes in neighboring cells. These studies provide the first biochemical and genetic evidence that selective cleavage of the S2 site of proDPP provides a tissue-specific mechanism for regulating Dpp activity, and that differential cleavage can contribute to, but is not an absolute determinant of signaling range.
Collapse
Affiliation(s)
- Shailaja Sopory
- Department of Cell and Developmental Biology, Oregon Health and Science University, School of Medicine, 3181 SW Sam Jackson Park Road, Portland, OR 97239-3098, USA
| | | | | | | |
Collapse
|
36
|
Vervoort R, Ceulemans H, Van Aerschot L, D'Hooge R, David G. Genetic modification of the inner ear lateral semicircular canal phenotype of the Bmp4 haplo-insufficient mouse. Biochem Biophys Res Commun 2010; 394:780-5. [PMID: 20233579 DOI: 10.1016/j.bbrc.2010.03.069] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2010] [Accepted: 03/10/2010] [Indexed: 12/27/2022]
Abstract
In the mouse, development of the lateral semicircular canal of the inner ear is sensitive to Bmp4 heterozygosity. In the C57BL6 background 30% of the heterozygotes display circling behavior, 66% have a specific defect in the vestibular part of the inner ear, namely the constriction, interruption or absence of the lateral semicircular canal. Only mice having both ears affected display circling behavior. In the (C57BL6xCBA)N1 background, the penetrance of the canal phenotype is greatly reduced, and bilateral lateral canal defect is not sufficient to induce circling. We found association of the canal phenotype with the genotype of markers on chromosome 14 and 4, co-localizing with Ecs and Eclb identified in the Ecl mouse with similar lateral canal defects. Candidate genes to contain the causal mutation are Bmp4 on chromosome 14, and Rere on chromosome 4.
Collapse
Affiliation(s)
- Raf Vervoort
- Laboratory of Glycobiology and Developmental Genetics, Flanders Institute for Biotechnology (VIB) and Department of Human Genetics, Katholieke Universiteit Leuven, Herestraat 49 bus 602, B-3000 Leuven, Belgium.
| | | | | | | | | |
Collapse
|
37
|
Nelsen SM, Christian JL. Site-specific cleavage of BMP4 by furin, PC6, and PC7. J Biol Chem 2009; 284:27157-66. [PMID: 19651771 PMCID: PMC2785643 DOI: 10.1074/jbc.m109.028506] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2009] [Revised: 07/27/2009] [Indexed: 11/06/2022] Open
Abstract
Bone morphogenetic proteins (BMPs) require proteolytic activation by members of the proprotein convertase (PC) family. Pro-BMP4 is initially cleaved at a site adjacent to the mature ligand domain (S1) and then at an upstream site (S2) within the prodomain. Cleavage at the S2 site, which appears to occur in a tissue-specific fashion, regulates the activity and signaling range of mature BMP4. To test the hypothesis that tissue-specific cleavage of pro-BMP4 is regulated by differential expression of a site-specific protease, we identified the PCs that cleave each site in vivo. In Xenopus oocytes, furin and PC6 function redundantly to cleave both the S1 and S2 sites of pro-BMP4, as evidenced by the results of antisense-mediated gene knockdown and the use of the furin- and PC6-selective inhibitor alpha(1)-PDX. By contrast, alpha(1)-PDX blocked cleavage of the S2 but not the S1 site of pro-BMP4 in embryos, suggesting the existence of a developmentally regulated S1 site-specific convertase. This protease is likely to be PC7 based on knowledge of its required substrate cleavage motif and resistance to alpha(1)-PDX. Consistent with this prediction, an alpha(1)-PDX variant engineered to target PC7, in addition to furin and PC6, completely inhibited cleavage of BMP4 in oocytes and embryos. Further studies showed that pc7 transcripts are expressed and polyadenylated, and that the PC7 precursor protein undergoes efficient autocatalytic activation in both oocytes and embryos. These results suggest that PC7, or a convertase with similar substrate specificity, functions to selectively cleave the S1 site of pro-BMP4 in a developmentally regulated fashion.
Collapse
Affiliation(s)
| | - Jan L. Christian
- Cell and Developmental Biology, Oregon Health and Science University School of Medicine, Portland, Oregon 97239-3098
| |
Collapse
|
38
|
Uchimura T, Komatsu Y, Tanaka M, McCann KL, Mishina Y. Bmp2 and Bmp4 genetically interact to support multiple aspects of mouse development including functional heart development. Genesis 2009; 47:374-84. [PMID: 19391114 DOI: 10.1002/dvg.20511] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Bone morphogenetic proteins (BMPs) have multiple roles during embryogenesis. Current data indicate that the dosage of BMPs is tightly regulated for normal development in mice. Since Bmp2 or Bmp4 homozygous mutant mice show early embryonic lethality, we generated compound heterozygous mice for Bmp2 and Bmp4 to explore the impact of lowered dosage of these BMP ligands. Genotyping pups bred between Bmp2 and Bmp4 heterozygous mice revealed that the ratio of adult compound heterozygous mice for Bmp2 and Bmp4 is much lower than expected. During embryogenesis, the compound heterozygous embryos showed several abnormalities, including defects in eye formation, body wall closure defects, and ventricular septal defects (VSD) in the heart. However, the ratio of the compound heterozygous embryos was the same as expected. Caesarean sections at E18.5 revealed that half of the compound heterozygotes died soon after birth, and the majority of the dead individuals exhibited VSD. Survivors were able to grow to adults, but their body weight was significantly lower than control littermates. They demonstrated progressive abnormalities in the heart, eventually showing a branched leaflet in atrioventricular valves. These results suggest that the dosage of both BMP2 and 4 is critical for functional heart formation during embryogenesis and after birth.
Collapse
Affiliation(s)
- Takashi Uchimura
- Laboratory of Reproductive and Developmental Toxicology, National Institute of Environmental Sciences, National Institutes of Health, Research Triangle Park, North Carolina, USA
| | | | | | | | | |
Collapse
|
39
|
Abstract
Bone morphogenetic protein 4 (BMP4) is required for mesoderm commitment to the hematopoietic lineage during early embryogenesis. However, deletion of BMP4 is early embryonically lethal and its functional role in definitive hematopoiesis is unknown. Consequently, we used a BMP4 hypomorph to investigate the role of BMP4 in regulating hematopoietic stem cell (HSC) function and maintaining steady-state hematopoiesis in the adult. Reporter gene expression shows that Bmp4 is expressed in cells associated with the hematopoietic microenvironment including osteoblasts, endothelial cells, and megakaryocytes. Although resting hematopoiesis is normal in a BMP4-deficient background, the number of c-Kit+, Sca-1+, Lineage- cells is significantly reduced. Serial transplantation studies reveal that BMP4-deficient recipients have a microenvironmental defect that reduces the repopulating activity of wild-type HSCs. This defect is even more pronounced in a parabiosis model that demonstrates a profound reduction in wild-type hematopoietic cells within the bone marrow of BMP4-deficient recipients. Furthermore, wild-type HSCs that successfully engraft into the BMP4-deficient bone marrow show a marked decrease in functional stem cell activity when tested in a competitive repopulation assay. Taken together, these findings indicate BMP4 is a critical component of the hematopoietic microenvironment that regulates both HSC number and function.
Collapse
|
40
|
Künnapuu J, Björkgren I, Shimmi O. The Drosophila DPP signal is produced by cleavage of its proprotein at evolutionary diversified furin-recognition sites. Proc Natl Acad Sci U S A 2009; 106:8501-6. [PMID: 19433798 PMCID: PMC2689000 DOI: 10.1073/pnas.0809885106] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2008] [Indexed: 11/18/2022] Open
Abstract
Maturation of bone morphogenetic proteins (BMPs) requires cleavage of their precursor proteins by furin-type proprotein convertases. Here, we find that cleavage sites of the BMP2/4/decapentaplegic (DPP) subfamily have been evolutionary diversified and can be categorized into 4 different types. Cnidaria BMP2/4/DPP is considered to be a prototype containing only 1 furin site. Bilateria BMP2/4/DPP acquired an additional cleavage site with either the combination of minimal-optimal or optimal-optimal furin sites. DPPs belonging to Diptera, such as Drosophila and mosquito, and Lepidoptera of silkworm contain a third cleavage site between the 2 optimal furin sites. We studied how the 3 furin sites (FSI-III) of Drosophila DPP coordinate maturation of ligands and contribute to signals in vivo. Combining mutational analysis of furin-recognition sites and RNAi experiments, we found that the Drosophila DPP precursor is initially cleaved at an upstream furin-recognition site (FSII), with consequent cleavages at 2 furin sites (FSI and FSIII). Both Dfurin1 and Dfurin2 are involved in the processing of DPP proproteins. Biochemical and genetic analyses using cleavage mutants of DPP suggest the first cleavage at FSII to be critical and sufficient for long-range DPP signaling. Our data suggest that the Drosophila DPP precursor is cleaved in a different manner from vertebrate BMP4 even though they are functional orthologs. This indicates that the furin-cleavage sites in BMP2/4/DPP precursors are tolerant to mutations acquired through evolution and have adapted to different systems in diversified species.
Collapse
Affiliation(s)
- Jaana Künnapuu
- Institute of Biotechnology, University of Helsinki, P.O. Box 56 Viikinkaari 9, 00014, Helsinki, Finland
| | - Ida Björkgren
- Institute of Biotechnology, University of Helsinki, P.O. Box 56 Viikinkaari 9, 00014, Helsinki, Finland
| | - Osamu Shimmi
- Institute of Biotechnology, University of Helsinki, P.O. Box 56 Viikinkaari 9, 00014, Helsinki, Finland
| |
Collapse
|
41
|
Asai-Coakwell M, French CR, Ye M, Garcha K, Bigot K, Perera AG, Staehling-Hampton K, Mema SC, Chanda B, Mushegian A, Bamforth S, Doschak MR, Li G, Dobbs MB, Giampietro PF, Brooks BP, Vijayalakshmi P, Sauvé Y, Abitbol M, Sundaresan P, van Heyningen V, Pourquié O, Underhill TM, Waskiewicz AJ, Lehmann OJ. Incomplete penetrance and phenotypic variability characterize Gdf6-attributable oculo-skeletal phenotypes. Hum Mol Genet 2009; 18:1110-21. [PMID: 19129173 DOI: 10.1093/hmg/ddp008] [Citation(s) in RCA: 80] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Proteins of the bone morphogenetic protein (BMP) family are known to have a role in ocular and skeletal development; however, because of their widespread expression and functional redundancy, less progress has been made identifying the roles of individual BMPs in human disease. We identified seven heterozygous mutations in growth differentiation factor 6 (GDF6), a member of the BMP family, in patients with both ocular and vertebral anomalies, characterized their effects with a SOX9-reporter assay and western analysis, and demonstrated comparable phenotypes in model organisms with reduced Gdf6 function. We observed a spectrum of ocular and skeletal anomalies in morphant zebrafish, the latter encompassing defective tail formation and altered expression of somite markers noggin1 and noggin2. Gdf6(+/-) mice exhibited variable ocular phenotypes compatible with phenotypes observed in patients and zebrafish. Key differences evident between patients and animal models included pleiotropic effects, variable expressivity and incomplete penetrance. These data establish the important role of this determinant in ocular and vertebral development, demonstrate the complex genetic inheritance of these phenotypes, and further understanding of BMP function and its contributions to human disease.
Collapse
|
42
|
Goldman DC, Donley N, Christian JL. Genetic interaction between Bmp2 and Bmp4 reveals shared functions during multiple aspects of mouse organogenesis. Mech Dev 2008; 126:117-27. [PMID: 19116164 DOI: 10.1016/j.mod.2008.11.008] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2008] [Revised: 11/15/2008] [Accepted: 11/30/2008] [Indexed: 11/25/2022]
Abstract
Vertebrate Bmp2 and Bmp4 diverged from a common ancestral gene and encode closely related proteins. Mice homozygous for null mutations in either gene show early embryonic lethality, thereby precluding analysis of shared functions. In the current studies, we present phenotypic analysis of compound mutant mice heterozygous for a null allele of Bmp2 in combination with null or hypomorphic alleles of Bmp4. Whereas mice lacking a single copy of Bmp2 or Bmp4 are viable and have subtle developmental defects, compound mutants show embryonic and postnatal lethality due to defects in multiple organ systems including the allantois, placental vasculature, ventral body wall, skeleton, eye and heart. Within the heart, BMP2 and BMP4 function coordinately to direct normal lengthening of the outflow tract, proper positioning of the outflow vessels, and septation of the atria, ventricle and atrioventricular canal. Our results identify numerous BMP4-dependent developmental processes that are also very sensitive to BMP2 dosage, thus revealing novel functions of Bmp2.
Collapse
Affiliation(s)
- Devorah C Goldman
- Department of Cell and Developmental Biology, Oregon Health and Sciences University, School of Medicine, 3181 SW Sam Jackson Park Road, Portland, OR 97239-3098, USA
| | | | | |
Collapse
|
43
|
Watanabe T, Sato T, Amano T, Kawamura Y, Kawamura N, Kawaguchi H, Yamashita N, Kurihara H, Nakaoka T. Dnm3os, a non-coding RNA, is required for normal growth and skeletal development in mice. Dev Dyn 2008; 237:3738-48. [DOI: 10.1002/dvdy.21787] [Citation(s) in RCA: 115] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
|
44
|
Williams T. Animal models of ventral body wall closure defects: A personal perspective on gastroschisis. AMERICAN JOURNAL OF MEDICAL GENETICS PART C-SEMINARS IN MEDICAL GENETICS 2008; 148C:186-91. [DOI: 10.1002/ajmg.c.30179] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
|
45
|
Szumska D, Pieles G, Essalmani R, Bilski M, Mesnard D, Kaur K, Franklyn A, El Omari K, Jefferis J, Bentham J, Taylor JM, Schneider JE, Arnold SJ, Johnson P, Tymowska-Lalanne Z, Stammers D, Clarke K, Neubauer S, Morris A, Brown SD, Shaw-Smith C, Cama A, Capra V, Ragoussis J, Constam D, Seidah NG, Prat A, Bhattacharya S. VACTERL/caudal regression/Currarino syndrome-like malformations in mice with mutation in the proprotein convertase Pcsk5. Genes Dev 2008; 22:1465-77. [PMID: 18519639 DOI: 10.1101/gad.479408] [Citation(s) in RCA: 105] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
We have identified an ethylnitrosourea (ENU)-induced recessive mouse mutation (Vcc) with a pleiotropic phenotype that includes cardiac, tracheoesophageal, anorectal, anteroposterior patterning defects, exomphalos, hindlimb hypoplasia, a presacral mass, renal and palatal agenesis, and pulmonary hypoplasia. It results from a C470R mutation in the proprotein convertase PCSK5 (PC5/6). Compound mutants (Pcsk5(Vcc/null)) completely recapitulate the Pcsk5(Vcc/Vcc) phenotype, as does an epiblast-specific conditional deletion of Pcsk5. The C470R mutation ablates a disulfide bond in the P domain, and blocks export from the endoplasmic reticulum and proprotein convertase activity. We show that GDF11 is cleaved and activated by PCSK5A, but not by PCSK5A-C470R, and that Gdf11-deficient embryos, in addition to having anteroposterior patterning defects and renal and palatal agenesis, also have a presacral mass, anorectal malformation, and exomphalos. Pcsk5 mutation results in abnormal expression of several paralogous Hox genes (Hoxa, Hoxc, and Hoxd), and of Mnx1 (Hlxb9). These include known Gdf11 targets, and are necessary for caudal embryo development. We identified nonsynonymous mutations in PCSK5 in patients with VACTERL (vertebral, anorectal, cardiac, tracheoesophageal, renal, limb malformation OMIM 192350) and caudal regression syndrome, the phenotypic features of which resemble the mouse mutation. We propose that Pcsk5, at least in part via GDF11, coordinately regulates caudal Hox paralogs, to control anteroposterior patterning, nephrogenesis, skeletal, and anorectal development.
Collapse
Affiliation(s)
- Dorota Szumska
- Department of Cardiovascular Medicine and Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford OX3 7BN, United Kingdom
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
46
|
Tassabehji M, Fang ZM, Hilton EN, McGaughran J, Zhao Z, de Bock CE, Howard E, Malass M, Donnai D, Diwan A, Manson FD, Murrell D, Clarke RA. Mutations in GDF6 are associated with vertebral segmentation defects in Klippel-Feil syndrome. Hum Mutat 2008; 29:1017-27. [DOI: 10.1002/humu.20741] [Citation(s) in RCA: 148] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
|
47
|
Rielland M, Hue I, Renard JP, Alice J. Trophoblast stem cell derivation, cross-species comparison and use of nuclear transfer: new tools to study trophoblast growth and differentiation. Dev Biol 2008; 322:1-10. [PMID: 18680738 DOI: 10.1016/j.ydbio.2008.07.017] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2008] [Revised: 07/04/2008] [Accepted: 07/09/2008] [Indexed: 12/25/2022]
Abstract
The trophoblast is a supportive tissue in mammals that plays key roles in embryonic patterning, foetal growth and nutrition. It shows an extensive growth up to the formation of the placenta. This growth is believed to be fed by trophoblast stem cells able to self-renew and to give rise to the differentiated derivatives present in the placenta. In this review, we summarize recent data on the molecular regulation of the trophoblast in vivo and in vitro. Most data have been obtained in the mouse, however, whenever relevant, we compare this model to other mammals. In ungulates, the growth of the trophoblast displays some striking features that make these species interesting alternative models for the study of trophoblast development. After the transfer of somatic nuclei into oocytes, studies in the mouse and the cow have both underlined that the trophoblast may be a direct target of reprogramming defects and that its growth seems specifically affected. We propose that the study of TS cells derived from nuclear transfer embryos may help to unravel some of the epigenetic abnormalities which occur therein.
Collapse
Affiliation(s)
- Maite Rielland
- INRA, UMR 1198 Biologie du Developpement et Reproduction, F-78350 Jouy en Josas, France
| | | | | | | |
Collapse
|
48
|
Sengle G, Charbonneau NL, Ono RN, Sasaki T, Alvarez J, Keene DR, Bächinger HP, Sakai LY. Targeting of bone morphogenetic protein growth factor complexes to fibrillin. J Biol Chem 2008; 283:13874-88. [PMID: 18339631 DOI: 10.1074/jbc.m707820200] [Citation(s) in RCA: 179] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Both latent transforming growth factor-beta (TGF-beta)-binding proteins fibrillins are components of microfibril networks, and both interact with members of the TGF-beta family of growth factors. Interactions between latent TGF-beta-binding protein-1 and TGF-beta and between fibrillin-1 and bone morphogenetic protein-7 (BMP-7) are mediated by the prodomain of growth factor complexes. To extend this information, investigations were performed to test whether stable complexes are formed by additional selected TGF-beta family members. Using velocity sedimentation in sucrose gradients as an assay, complex formation was demonstrated for BMP-7 and growth and differentiation factor-8 (GDF-8), which are known to exist in prodomain/growth factor complexes. Comparison of these results with complex formation by BMP-2, BMP-4 (full-length and shortened propeptides), BMP-10, and GDF-5 allowed us to conclude that all, except for BMP-2 and the short BMP-4 propeptides, formed complexes with their growth factors. Using surface plasmon resonance, binding affinities between fibrillin and all propeptides were determined. Binding studies revealed that the N-terminal end of fibrillin-1 serves as a universal high affinity docking site for the propeptides of BMP-2, -4, -7, and -10 and GDF-5, but not GDF-8, and located the BMP/GDF binding site within the N-terminal domain in fibrillin-1. Rotary shadowing electron microscopy of molecules of BMP-7 complex bound to fibrillin-1 confirmed these findings and also showed that prodomain binding targets the growth factor to fibrillin. Immunolocalization of BMP-4 demonstrated fibrillar staining limited to certain tissues, indicating tissue-specific targeting of BMP-4. These data implicate the fibrillin microfibril network in the extracellular control of BMP signaling and demonstrate differences in how prodomains target their growth factors to the extracellular space.
Collapse
Affiliation(s)
- Gerhard Sengle
- Shriners Hospital for Children, Portland, Oregon 97239, USA
| | | | | | | | | | | | | | | |
Collapse
|
49
|
Westmoreland JJ, Takahashi S, Wright CVE. Xenopus Lefty requires proprotein cleavage but not N-linked glycosylation to inhibit nodal signaling. Dev Dyn 2007; 236:2050-61. [PMID: 17584861 DOI: 10.1002/dvdy.21210] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
The Nodal and Nodal-related morphogens are utilized for the specification of distinct cellular identity throughout development by activating discrete target genes in a concentration-dependant manner. Lefty is a principal extracellular antagonist involved in the spatiotemporal regulation of the Nodal morphogen gradient during mesendoderm induction. The Xenopus Lefty proprotein contains a single N-linked glycosylation motif in the mature domain and two potential cleavage sites that would be expected to produce long (Xlefty(L)) and short (Xlefty(S)) isoforms. Here we demonstrate that both isoforms were secreted from Xenopus oocytes, but that Xlefty(L) is the only isoform detected when embryonic tissue was analyzed. In mesoderm induction assays, Xlefty(L) is the functional blocker of Xnr signaling. When secreted from oocytes, vertebrate Lefty molecules were N-linked glycosylated. However, glycan addition was not required to inhibit Xnr signaling and did not influence its movement through the extracellular space. These findings demonstrate that Lefty molecules undergo post-translational modifications and that some of these modifications are required for the Nodal inhibitory function.
Collapse
Affiliation(s)
- Joby J Westmoreland
- Vanderbilt University Program in Developmental Biology, Department of Cell and Developmental Biology, Vanderbilt University School of Medicine, Nashville, Tennessee 37232, USA
| | | | | |
Collapse
|
50
|
Mayer G, Hamelin J, Asselin MC, Pasquato A, Marcinkiewicz E, Tang M, Tabibzadeh S, Seidah NG. The regulated cell surface zymogen activation of the proprotein convertase PC5A directs the processing of its secretory substrates. J Biol Chem 2007; 283:2373-84. [PMID: 18039650 DOI: 10.1074/jbc.m708763200] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The proprotein convertases are synthesized as zymogens that acquire activity upon autocatalytic removal of their NH(2)-terminal prosegment. Based on the convertase furin, to fold properly and gain activity, the convertases PC5A, PACE4, and PC7 are presumed to undergo two sequential prosegment cleavages in the endoplasmic reticulum and then in the trans-Golgi network. However, biochemical and immunocytochemical experiments revealed that mouse PC5A is complexed to its prosegment at the plasma membrane. This labeling is lost upon treatment with heparin and is increased by overexpressing members of the syndecan family and CD44, suggesting attachment of secreted PC5A-prosegment complex to heparan sulfate proteoglycans. Following stimulation of Y1 cells with adrenocorticotropic hormone or 8-bromo-cyclic AMP, the cell surface labeling of the prosegment of PC5A is greatly diminished, whereas the signal for mature PC5A is increased. Moreover, after stimulation, the protease activity of PC5A is enhanced, as evidenced by the cleavage of the PC5A substrates Lefty, ADAMTS-4, endothelial lipase, and PCSK9. Our data suggest a novel mechanism for PC5A activation and substrate cleavage at the cell surface, through a regulated removal of its prosegment. A similar mechanism may also apply to the convertase PACE4, thereby extending our knowledge of the molecular details of the zymogen activation and functions of these heparan sulfate proteoglycan-bound convertases.
Collapse
Affiliation(s)
- Gaétan Mayer
- Laboratory of Biochemical Neuroendocrinology, Clinical Research Institute of Montreal, Montréal, Quebec H2W 1R7, Canada
| | | | | | | | | | | | | | | |
Collapse
|