1
|
Xue Y, Pei X, Xia Y, Chen H, Yu H, Wang W, Mao D. RGMb expression in goat uterine tissues: possible role of RGMb in the proliferation and apoptosis of endometrial epithelial cells. Reprod Fertil Dev 2023; 35:723-732. [PMID: 37967584 DOI: 10.1071/rd23121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2023] [Accepted: 10/26/2023] [Indexed: 11/17/2023] Open
Abstract
Context Bone morphogenetic proteins (BMPs) play an important role in the uteri. Repulsive guidance molecule b (RGMb; a.k.a. Dragon) has been confirmed as the coreceptor of BMPs to function through drosophila mothers against decapentaplegic protein (Smads) and mitogen-activated protein kinases (MAPK) pathways. We hypothesise that RGMb regulates the uterine function through the Smads and MAPK pathways. Aims This study aimed to investigate the expression of RGMb in goat uteri and the potential role of RGMb in the endometrial epithelial cells (EECs). Methods The localisation of RGMb in goat uterine tissues was detected by immunohistochemistry (IHC), EECs were isolated and transfected with siRNA to investigate the role of RGMb in proliferation, and apoptosis. The expression levels of Smads and MAPK members was measured by western blot (WB) and real-time PCR (RT-PCR). Key results IHC showed that RGMb was localised in goat endometrial luminal cells, glandular epithelial cells, and circular muscle fibres, but not in stromal cells. RT-PCR results showed that treatment with RGMb siRNA suppressed the expressions of proliferation-related genes cyclin D1 (CCND1 , P =0.0291), cyclin-dependent kinase 2 (CDK2 P =0.0107), and proliferating cell nuclear antigen (PCNA, P =0.0508), leading to the reduced viability of EECs (P =0.0010). WB results showed that the expression ratio of cleaved-caspase 3/caspase 3 (P =0.0013) was markedly increased after RGMb siRNA transfection. Likewise, the level of phospho-extracellular signal-regulated kinase 1/2 (p-ERK1/2, P =0.0068) and p-Smad1/5/8 (P =0.0011) decreased significantly, while there were no appreciable differences in the level of p-P38 MAPK expression (P >0.05). Conclusions RGMb might participate in the regulation of cell proliferation and apoptosis through Smads and ERK signalling pathways in goat EECs. Implications RGMb is involved in regulating the proliferation and apoptosis in goat endometrial epithelial cells.
Collapse
Affiliation(s)
- Yang Xue
- College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, Jiangsu 210095, China
| | - Xiaomeng Pei
- College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, Jiangsu 210095, China
| | - Yuting Xia
- College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, Jiangsu 210095, China
| | - Hengguang Chen
- College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, Jiangsu 210095, China
| | - Hao Yu
- College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, Jiangsu 210095, China
| | - Wei Wang
- College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, Jiangsu 210095, China
| | - Dagan Mao
- College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, Jiangsu 210095, China
| |
Collapse
|
2
|
Dorset SR, Daugaard TF, Larsen TV, Nielsen AL. RGMb impacts partial epithelial-mesenchymal transition and BMP2-Induced ID mRNA expression independent of PD-L2 in nonsmall cell lung cancer cells. Cell Biol Int 2023; 47:1799-1812. [PMID: 37434531 DOI: 10.1002/cbin.12071] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2022] [Revised: 05/26/2023] [Accepted: 07/05/2023] [Indexed: 07/13/2023]
Abstract
PD-1/PD-ligand-axis immunotherapy-mediated activation of T-cells for cancer cell elimination is a promising treatment of nonsmall cell lung cancer (NSCLC). However, the effect of immunotherapy on intracellular signaling pathways in cancer cells still needs further delineation. Repulsive Guidance Molecule b (RGMb), a regulator of Bone Morphogenetic Proteins (BMPs) signaling, interacts with the PD-ligand, PD-L2, at cancer cell membranes. Accordingly, a clarification of the functions of RGMb and its relation to PD-L2 might provide insight into NSCLC cell signaling responses to PD-1/PD-ligand-axis immunotherapy. In this study, the functions of RGMb and PD-L2 were examined using the two NSCLC cell lines HCC827 and A549. CRISPR/Cas9 was used to decrease the expression of RGMb and PD-L2, while lentiviral vectors were used to increase their expression. Downstream effects were examined by RT-qPCR and immunoassays. Ectopic expression of RGMb impacted BMP2-induced expression of ID1 and ID2 messenger RNA (mRNA) independently of PD-L2, while RGMb depletion by CRISPR/Cas9 did not affect the BMP2-mediated induction of ID1, ID2, and ID3 mRNA. However, depletion of RGMb resulted in a partial epithelial-mesenchymal transition (EMT) gene expression profile in HCC827 cells, which was not mimicked by PD-L2 depletion. The results show that RGMb is a coregulator of BMP signaling and hence, ID mRNA expression and that RGMb can control the EMT balance in NSCLC cells. However, RGMb appears to exert these functions independently of PD-L2, and accordingly, the PD-1/PD-ligand axis for immune surveillance in NSCLC cells.
Collapse
|
3
|
Park JS, Gazzaniga FS, Wu M, Luthens AK, Gillis J, Zheng W, LaFleur MW, Johnson SB, Morad G, Park EM, Zhou Y, Watowich SS, Wargo JA, Freeman GJ, Kasper DL, Sharpe AH. Targeting PD-L2-RGMb overcomes microbiome-related immunotherapy resistance. Nature 2023; 617:377-385. [PMID: 37138075 PMCID: PMC10219577 DOI: 10.1038/s41586-023-06026-3] [Citation(s) in RCA: 31] [Impact Index Per Article: 31.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2022] [Accepted: 03/28/2023] [Indexed: 05/05/2023]
Abstract
The gut microbiota is a crucial regulator of anti-tumour immunity during immune checkpoint inhibitor therapy. Several bacteria that promote an anti-tumour response to immune checkpoint inhibitors have been identified in mice1-6. Moreover, transplantation of faecal specimens from responders can improve the efficacy of anti-PD-1 therapy in patients with melanoma7,8. However, the increased efficacy from faecal transplants is variable and how gut bacteria promote anti-tumour immunity remains unclear. Here we show that the gut microbiome downregulates PD-L2 expression and its binding partner repulsive guidance molecule b (RGMb) to promote anti-tumour immunity and identify bacterial species that mediate this effect. PD-L1 and PD-L2 share PD-1 as a binding partner, but PD-L2 can also bind RGMb. We demonstrate that blockade of PD-L2-RGMb interactions can overcome microbiome-dependent resistance to PD-1 pathway inhibitors. Antibody-mediated blockade of the PD-L2-RGMb pathway or conditional deletion of RGMb in T cells combined with an anti-PD-1 or anti-PD-L1 antibody promotes anti-tumour responses in multiple mouse tumour models that do not respond to anti-PD-1 or anti-PD-L1 alone (germ-free mice, antibiotic-treated mice and even mice colonized with stool samples from a patient who did not respond to treatment). These studies identify downregulation of the PD-L2-RGMb pathway as a specific mechanism by which the gut microbiota can promote responses to PD-1 checkpoint blockade. The results also define a potentially effective immunological strategy for treating patients who do not respond to PD-1 cancer immunotherapy.
Collapse
Affiliation(s)
- Joon Seok Park
- Department of Immunology, Blavatnik Institute, Harvard Medical School, Boston, MA, USA
| | - Francesca S Gazzaniga
- Department of Immunology, Blavatnik Institute, Harvard Medical School, Boston, MA, USA
- Molecular Pathology Unit, Massachusetts General Hospital, Charlestown, MA, USA
- Department of Pathology, Harvard Medical School, Boston, MA, USA
| | - Meng Wu
- Department of Immunology, Blavatnik Institute, Harvard Medical School, Boston, MA, USA
| | - Amalia K Luthens
- Department of Immunology, Blavatnik Institute, Harvard Medical School, Boston, MA, USA
| | - Jacob Gillis
- Department of Immunology, Blavatnik Institute, Harvard Medical School, Boston, MA, USA
| | - Wen Zheng
- Department of Immunology, Blavatnik Institute, Harvard Medical School, Boston, MA, USA
| | - Martin W LaFleur
- Department of Immunology, Blavatnik Institute, Harvard Medical School, Boston, MA, USA
| | - Sarah B Johnson
- Program for Innovative Microbiome and Translational Research, Department of Genomic Medicine, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Golnaz Morad
- Program for Innovative Microbiome and Translational Research, Department of Genomic Medicine, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Elizabeth M Park
- Program for Innovative Microbiome and Translational Research, Department of Genomic Medicine, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
- Department of Immunology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
- Department of Surgical Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Yifan Zhou
- Program for Innovative Microbiome and Translational Research, Department of Genomic Medicine, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
- Department of Immunology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Stephanie S Watowich
- Program for Innovative Microbiome and Translational Research, Department of Genomic Medicine, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
- Department of Immunology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Jennifer A Wargo
- Program for Innovative Microbiome and Translational Research, Department of Genomic Medicine, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
- Department of Surgical Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
- Department of Genomic Medicine, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Gordon J Freeman
- Department of Medical Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA, USA.
| | - Dennis L Kasper
- Department of Immunology, Blavatnik Institute, Harvard Medical School, Boston, MA, USA.
| | - Arlene H Sharpe
- Department of Immunology, Blavatnik Institute, Harvard Medical School, Boston, MA, USA.
- Department of Pathology, Harvard Medical School, Boston, MA, USA.
| |
Collapse
|
4
|
do Carmo Costa A, Copola AGL, Carvalho E Souza C, Nogueira JM, Silva GAB, Jorge EC. RGMa can induce skeletal muscle cell hyperplasia via association with neogenin signalling pathway. In Vitro Cell Dev Biol Anim 2021; 57:415-427. [PMID: 33748906 DOI: 10.1007/s11626-021-00555-9] [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: 09/09/2020] [Accepted: 02/15/2021] [Indexed: 11/29/2022]
Abstract
Although originally discovered inducing important biological functions in the nervous system, repulsive guidance molecule a (RGMa) has now been identified as a player in many other processes and diseases, including in myogenesis. RGMa is known to be expressed in skeletal muscle cells, from somites to the adult. Functional in vitro studies have revealed that RGMa overexpression could promote skeletal muscle cell hypertrophy and hyperplasia, as higher efficiency in cell fusion was observed. Here, we extend the potential role of RGMa during C2C12 cell differentiation in vitro. Our results showed that RGMa administrated as a recombinant protein during late stages of C2C12 myogenic differentiation could induce myoblast cell fusion and the downregulation of different myogenic markers, while its administration at early stages induced the expression of myogenic markers with no detectable morphological effects. We also found that RGMa effects on skeletal muscle hyperplasia are performed via neogenin receptor, possibly as part of a complex with other proteins. Additionally, we observed that RGMa-neogenin is not playing a role as an inhibitor of the BMP signalling in skeletal muscle cells. This work contributes to placing RGMa as a component of the mechanisms that determine skeletal cell fusion via neogenin receptor.
Collapse
Affiliation(s)
- Alinne do Carmo Costa
- Department of Morphology, Institute of Biological Sciences, Federal University of Minas Gerais, Av Antonio Carlos, 6627, Pampulha, Belo Horizonte, Minas Gerais, 31.270-901, Brazil
| | - Aline Gonçalves Lio Copola
- Department of Morphology, Institute of Biological Sciences, Federal University of Minas Gerais, Av Antonio Carlos, 6627, Pampulha, Belo Horizonte, Minas Gerais, 31.270-901, Brazil
| | - Clara Carvalho E Souza
- Department of Morphology, Institute of Biological Sciences, Federal University of Minas Gerais, Av Antonio Carlos, 6627, Pampulha, Belo Horizonte, Minas Gerais, 31.270-901, Brazil
| | - Júlia Meireles Nogueira
- Department of Morphology, Institute of Biological Sciences, Federal University of Minas Gerais, Av Antonio Carlos, 6627, Pampulha, Belo Horizonte, Minas Gerais, 31.270-901, Brazil
| | - Gerluza Aparecida Borges Silva
- Department of Morphology, Institute of Biological Sciences, Federal University of Minas Gerais, Av Antonio Carlos, 6627, Pampulha, Belo Horizonte, Minas Gerais, 31.270-901, Brazil
| | - Erika Cristina Jorge
- Department of Morphology, Institute of Biological Sciences, Federal University of Minas Gerais, Av Antonio Carlos, 6627, Pampulha, Belo Horizonte, Minas Gerais, 31.270-901, Brazil.
| |
Collapse
|
5
|
Human kidney clonal proliferation disclose lineage-restricted precursor characteristics. Sci Rep 2020; 10:22097. [PMID: 33328501 PMCID: PMC7745030 DOI: 10.1038/s41598-020-78366-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2020] [Accepted: 11/02/2020] [Indexed: 01/10/2023] Open
Abstract
In-vivo single cell clonal analysis in the adult mouse kidney has previously shown lineage-restricted clonal proliferation within varying nephron segments as a mechanism responsible for cell replacement and local regeneration. To analyze ex-vivo clonal growth, we now preformed limiting dilution to generate genuine clonal cultures from one single human renal epithelial cell, which can give rise to up to 3.4 * 106 cells, and analyzed their characteristics using transcriptomics. A comparison between clonal cultures revealed restriction to either proximal or distal kidney sub-lineages with distinct cellular and molecular characteristics; rapidly amplifying de-differentiated clones and a stably proliferating cuboidal epithelial-appearing clones, respectively. Furthermore, each showed distinct molecular features including cell-cycle, epithelial-mesenchymal transition, oxidative phosphorylation, BMP signaling pathway and cell surface markers. In addition, analysis of clonal versus bulk cultures show early clones to be more quiescent, with elevated expression of renal developmental genes and overall reduction in renal identity markers, but with an overlapping expression of nephron segment identifiers and multiple identity. Thus, ex-vivo clonal growth mimics the in-vivo situation displaying lineage-restricted precursor characteristics of mature renal cells. These data suggest that for reconstruction of varying renal lineages with human adult kidney based organoid technology and kidney regeneration ex-vivo, use of multiple heterogeneous precursors is warranted.
Collapse
|
6
|
Time-course transcriptome analysis of lungs from mice exposed to ricin by intratracheal inoculation. Toxicol Lett 2020; 337:57-67. [PMID: 33232776 DOI: 10.1016/j.toxlet.2020.11.012] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2020] [Revised: 07/23/2020] [Accepted: 11/16/2020] [Indexed: 11/23/2022]
Abstract
In this study, a ricin toxin (RT)-induced pulmonary intoxication model was established in mice by intratracheal-delivered RT at a dose of 2× LD50. Based on this model, the histopathological evaluation of the lungs at 24 h and 48 h post-exposure was executed, and the genome-wide transcriptome of the lungs at 4, 12, 24 and 48 h post-exposure was analyzed. Histopathological analysis showed that a large number of neutrophils infiltrated the lungs at 24 h post-exposure, and slight pulmonary edema and perivascular-peribronchiolar edema appeared in the lungs at 48 h. Transcriptome analysis showed that the expression of a large number of genes related to leukocyte migration and chemotaxis consistently increased in the lungs upon exposure to RT, and the expression of genes that participate in acute phase immune and/or inflammatory response, also increased within 12 h of exposure to RT, which could be confirmed by the measurement of cytokines, such as IL-1β, TNF-α and IL-6, in bronchoalveolar lavage fluid. While the expression of genes related to cellular components of the extracellular matrix and cell membrane integrity consistently decreased in the lungs, and the expression of genes related to antioxidant activity also decreased within the first 12 h. There are 17 differentially expressed genes (DEGs) that participate in ribotoxic stress response, endoplasmic reticulum stress response or immune response in the lungs at 4 h post-exposure. The expression of these DEGs was upregulated, and the number of these DEGs accounted for about 59 % of all DEGs at 4 h. The 17 DEGs may play an important role in the occurrence and development of inflammation. Notably, Atf3, Egr1, Gdf15 and Osm, which are poorly studied, may be important targets for the subsequent research of RT-induced pulmonary intoxication. This study provides new information and insights for RT-induced pulmonary intoxication, and it can provide a reference for the subsequent study of the toxicological mechanism and therapeutic approaches for RT-induced pulmonary intoxication.
Collapse
|
7
|
Halloran D, Durbano HW, Nohe A. Bone Morphogenetic Protein-2 in Development and Bone Homeostasis. J Dev Biol 2020; 8:jdb8030019. [PMID: 32933207 PMCID: PMC7557435 DOI: 10.3390/jdb8030019] [Citation(s) in RCA: 121] [Impact Index Per Article: 30.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2020] [Revised: 09/01/2020] [Accepted: 09/11/2020] [Indexed: 12/11/2022] Open
Abstract
Bone morphogenetic proteins (BMPs) are multi-functional growth factors belonging to the Transforming Growth Factor-Beta (TGF-β) superfamily. These proteins are essential to many developmental processes, including cardiogenesis, neurogenesis, and osteogenesis. Specifically, within the BMP family, Bone Morphogenetic Protein-2 (BMP-2) was the first BMP to be characterized and has been well-studied. BMP-2 has important roles during embryonic development, as well as bone remodeling and homeostasis in adulthood. Some of its specific functions include digit formation and activating osteogenic genes, such as Runt-Related Transcription Factor 2 (RUNX2). Because of its diverse functions and osteogenic potential, the Food and Drug Administration (FDA) approved usage of recombinant human BMP-2 (rhBMP-2) during spinal fusion surgery, tibial shaft repair, and maxillary sinus reconstructive surgery. However, shortly after initial injections of rhBMP-2, several adverse complications were reported, and alternative therapeutics have been developed to limit these side-effects. As the clinical application of BMP-2 is largely implicated in bone, we focus primarily on its role in bone. However, we also describe briefly the role of BMP-2 in development. We then focus on the structure of BMP-2, its activation and regulation signaling pathways, BMP-2 clinical applications, and limitations of using BMP-2 as a therapeutic. Further, this review explores other potential treatments that may be useful in treating bone disorders.
Collapse
Affiliation(s)
| | | | - Anja Nohe
- Correspondence: ; Tel.: +1-302-831-6977
| |
Collapse
|
8
|
Yu S, Leung KM, Kim HY, Umetsu SE, Xiao Y, Albacker LA, Lee HJ, Umetsu DT, Freeman GJ, DeKruyff RH. Blockade of RGMb inhibits allergen-induced airways disease. J Allergy Clin Immunol 2019; 144:94-108.e11. [PMID: 30703386 PMCID: PMC8088837 DOI: 10.1016/j.jaci.2018.12.1022] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2017] [Revised: 11/20/2018] [Accepted: 12/07/2018] [Indexed: 12/13/2022]
Abstract
BACKGROUND Allergic asthma causes morbidity in many subjects, and novel precision-directed treatments would be valuable. OBJECTIVE We sought to examine the role of a novel innate molecule, repulsive guidance molecule b (RGMb), in murine models of allergic asthma. METHODS In models of allergic asthma using ovalbumin or cockroach allergen, mice were treated with anti-RGMb or control mAb and examined for airway inflammation and airway hyperreactivity (AHR), a cardinal feature of asthma. The mechanisms by which RGMb causes airways disease were also examined. RESULTS We found that blockade of RGMb by treatment with anti-RGMb mAb effectively blocked the development of airway inflammation and AHR. Importantly, blockade of RGMb completely blocked the development of airway inflammation and AHR, even if treatment occurred only during the challenge (effector) phase. IL-25 played an important role in these models of asthma because IL-25 receptor-deficient mice did not develop disease after sensitization and challenge with allergen. RGMb was expressed primarily by innate cells in the lungs, including bronchial epithelial cells (known producers of IL-25), activated eosinophils, and interstitial macrophages, which in the inflamed lung expressed the IL-25 receptor and produced IL-5 and IL-13. We also found that neogenin, the canonical receptor for RGMb, was expressed by interstitial macrophages and bronchial epithelial cells in the inflamed lung, suggesting that an innate RGMb-neogenin axis might modulate allergic asthma. CONCLUSIONS These results demonstrate an important role for a novel innate pathway in regulating type 2 inflammation in patients with allergic asthma involving RGMb and RGMb-expressing cells, such as interstitial macrophages and bronchial epithelial cells. Moreover, targeting this previously unappreciated innate pathway might provide an important treatment option for allergic asthma.
Collapse
Affiliation(s)
- Sanhong Yu
- Department of Medical Oncology, Dana-Farber Cancer Institute, Department of Medicine, Harvard Medical School, Boston, Mass; Boston Children's Hospital, Harvard Medical School, Boston, Mass
| | - Krystle M Leung
- Boston Children's Hospital, Harvard Medical School, Boston, Mass
| | - Hye-Young Kim
- Boston Children's Hospital, Harvard Medical School, Boston, Mass
| | - Sarah E Umetsu
- Department of Pathology, University of California, San Francisco, Calif
| | - Yanping Xiao
- Department of Medical Oncology, Dana-Farber Cancer Institute, Department of Medicine, Harvard Medical School, Boston, Mass
| | - Lee A Albacker
- Boston Children's Hospital, Harvard Medical School, Boston, Mass; Immunology Program, Harvard Medical School, Boston, Mass
| | - Hyun-Jun Lee
- Boston Children's Hospital, Harvard Medical School, Boston, Mass
| | - Dale T Umetsu
- Boston Children's Hospital, Harvard Medical School, Boston, Mass
| | - Gordon J Freeman
- Department of Medical Oncology, Dana-Farber Cancer Institute, Department of Medicine, Harvard Medical School, Boston, Mass
| | - Rosemarie H DeKruyff
- Boston Children's Hospital, Harvard Medical School, Boston, Mass; Sean N Parker Center for Allergy and Asthma Research, Department of Medicine, Stanford University, Stanford, Calif.
| |
Collapse
|
9
|
Ren T, Zheng B, Huang Y, Wang S, Bao X, Liu K, Guo W. Osteosarcoma cell intrinsic PD-L2 signals promote invasion and metastasis via the RhoA-ROCK-LIMK2 and autophagy pathways. Cell Death Dis 2019; 10:261. [PMID: 30886151 PMCID: PMC6423010 DOI: 10.1038/s41419-019-1497-1] [Citation(s) in RCA: 50] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2018] [Revised: 01/29/2019] [Accepted: 03/04/2019] [Indexed: 12/15/2022]
Abstract
Known as co-stimulatory molecule, programmed death ligand-2 (PD-L2) contributes to T-cell exhaustion by interaction with programmed death-1 (PD-1) receptor, but its tumor cell-intrinsic signal effects have been little investigated. PD-L2 expression was detected by immunohistochemistry in 18 pairs of primary osteosarcoma tissues and matching lung metastasis tissues. We also investigated the effects of PD-L2 knockdown on osteosarcoma both in vitro and in vivo. In our study, PD-L2 expression was elevated in lung metastases compared with primary osteosarcoma according to an immunohistochemistry assay. Wound-healing and transwell assays revealed that PD-L2 knockdown leaded to inhibition of migration and invasion of human osteosarcoma cells in vitro. Mechanistically, we demonstrated that PD-L2 knockdown attenuated migration and invasion by inactivating RhoA-ROCK-LIMK2 signaling, suppressing epithelial–mesenchymal transition (EMT), and inhibiting autophagy by decreasing beclin-1 expression. In support of these observations, beclin-1 knockdown also inhibited activation of the RhoA-ROCK-LIMK2 pathway, leading to autophagy inhibition-induced blockade of migration and invasion. Depletion of PD-L2 in KHOS cells markedly weakens pulmonary metastatic potential in vivo by orthotopic transplantation of nude mice. Our study reveals a pro-metastatic functional mechanism for PD-L2 in osteosarcoma. Furthermore, we demonstrate a regulatory role for PD-L2 on autophagy, as well as a relationship between autophagy and metastasis in osteosarcoma, which may represent a potential therapeutic target for osteosarcoma.
Collapse
Affiliation(s)
- Tingting Ren
- Musculoskeletal Tumor Center, Peking University People's Hospital, Beijing, People's Republic of China.,Beijing Key Laboratory of Musculoskeletal Tumor, Beijing, People's Republic of China
| | - Bingxin Zheng
- Musculoskeletal Tumor Center, Peking University People's Hospital, Beijing, People's Republic of China.,Beijing Key Laboratory of Musculoskeletal Tumor, Beijing, People's Republic of China.,Department of Orthopedic Surgery, The Affiliated Hospital of Qingdao University, Qingdao, People's Republic of China
| | - Yi Huang
- Musculoskeletal Tumor Center, Peking University People's Hospital, Beijing, People's Republic of China.,Beijing Key Laboratory of Musculoskeletal Tumor, Beijing, People's Republic of China
| | - Shidong Wang
- Musculoskeletal Tumor Center, Peking University People's Hospital, Beijing, People's Republic of China.,Beijing Key Laboratory of Musculoskeletal Tumor, Beijing, People's Republic of China
| | - Xing Bao
- Musculoskeletal Tumor Center, Peking University People's Hospital, Beijing, People's Republic of China.,Beijing Key Laboratory of Musculoskeletal Tumor, Beijing, People's Republic of China
| | - Kuisheng Liu
- Musculoskeletal Tumor Center, Peking University People's Hospital, Beijing, People's Republic of China.,Beijing Key Laboratory of Musculoskeletal Tumor, Beijing, People's Republic of China
| | - Wei Guo
- Musculoskeletal Tumor Center, Peking University People's Hospital, Beijing, People's Republic of China. .,Beijing Key Laboratory of Musculoskeletal Tumor, Beijing, People's Republic of China.
| |
Collapse
|
10
|
Shi Y, Huang XX, Chen GB, Wang Y, Zhi Q, Liu YS, Wu XL, Wang LF, Yang B, Xiao CX, Xing HQ, Ren JL, Xia Y, Guleng B. Dragon (RGMb) induces oxaliplatin resistance in colon cancer cells. Oncotarget 2018; 7:48027-48037. [PMID: 27384995 PMCID: PMC5216997 DOI: 10.18632/oncotarget.10338] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2015] [Accepted: 06/12/2016] [Indexed: 02/01/2023] Open
Abstract
Colorectal cancer (CRC) is one of the most commonly diagnosed cancers and a major cause of cancer mortality. Chemotherapy resistance remains a major challenge for treating advanced CRC. Therefore, the identification of targets that induce drug resistance is a priority for the development of novel agents to overcome resistance. Dragon (also known as RGMb) is a member of the repulsive guidance molecule (RGM) family. We previously showed that Dragon expression increases with CRC progression in human patients. In the present study, we found that Dragon inhibited apoptosis and increased viability of CMT93 and HCT116 cells in the presence of oxaliplatin. Dragon induced resistance of xenograft tumor to oxaliplatinin treatment in mice. Mechanistically, Dragon inhibited oxaliplatin-induced JNK and p38 MAPK activation, and caspase-3 and PARP cleavages. Our results indicate that Dragon may be a novel target that induces drug resistance in CRC.
Collapse
Affiliation(s)
- Ying Shi
- Department of Gastroenterology, Zhongshan Hospital, Xiamen University, Xiamen, China
| | - Xiao-Xiao Huang
- Department of Gastroenterology, Zhongshan Hospital, Xiamen University, Xiamen, China
| | - Guo-Bin Chen
- Department of Gastroenterology, Zhongshan Hospital, Xiamen University, Xiamen, China.,Xiamen Branch, Zhongshan Hospital, Fudan University, Xiamen, China
| | - Ying Wang
- Department of Gastroenterology, Zhongshan Hospital, Xiamen University, Xiamen, China
| | - Qiang Zhi
- Department of Gastroenterology, Zhongshan Hospital, Xiamen University, Xiamen, China
| | - Yuan-Sheng Liu
- Department of Gastroenterology, Zhongshan Hospital, Xiamen University, Xiamen, China
| | - Xiao-Ling Wu
- Department of Gastroenterology, Zhongshan Hospital, Xiamen University, Xiamen, China
| | - Li-Fen Wang
- Department of Gastroenterology, Zhongshan Hospital, Xiamen University, Xiamen, China
| | - Bing Yang
- Department of Gastroenterology, Zhongshan Hospital, Xiamen University, Xiamen, China
| | - Chuan-Xing Xiao
- Department of Gastroenterology, Zhongshan Hospital, Xiamen University, Xiamen, China
| | - Hui-Qin Xing
- Department of Basic Medical Sciences, Institute of Neuroscience, Medical College of Xiamen University, Xiamen, China
| | - Jian-Lin Ren
- Department of Gastroenterology, Zhongshan Hospital, Xiamen University, Xiamen, China
| | - Yin Xia
- School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong, China.,School of Biomedical Sciences Core Laboratory, The Chinese University of Hong Kong Shenzhen Research Institute, Shenzhen, China
| | - Bayasi Guleng
- Department of Gastroenterology, Zhongshan Hospital, Xiamen University, Xiamen, China.,State Key Laboratory of Cellular Stress Biology, Xiamen University, Xiamen, China
| |
Collapse
|
11
|
RGMb protects against acute kidney injury by inhibiting tubular cell necroptosis via an MLKL-dependent mechanism. Proc Natl Acad Sci U S A 2018; 115:E1475-E1484. [PMID: 29382757 DOI: 10.1073/pnas.1716959115] [Citation(s) in RCA: 57] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Tubular cell necrosis is a key histological feature of acute kidney injury (AKI). Necroptosis is a type of programed necrosis, which is executed by mixed lineage kinase domain-like protein (MLKL) upon its binding to the plasma membrane. Emerging evidence indicates that necroptosis plays a critical role in the development of AKI. However, it is unclear whether renal tubular cells undergo necroptosis in vivo and how the necroptotic pathway is regulated during AKI. Repulsive guidance molecule (RGM)-b is a member of the RGM family. Our previous study demonstrated that RGMb is highly expressed in kidney tubular epithelial cells, but its biological role in the kidney has not been well characterized. In the present study, we found that RGMb reduced membrane-associated MLKL levels and inhibited necroptosis in cultured cells. During ischemia/reperfusion injury (IRI) or oxalate nephropathy, MLKL was induced to express on the apical membrane of proximal tubular (PT) cells. Specific knockout of Rgmb in tubular cells (Rgmb cKO) increased MLKL expression at the apical membrane of PT cells and induced more tubular cell death and more severe renal dysfunction compared with wild-type mice. Treatment with the necroptosis inhibitor Necrostatin-1 or GSK'963 reduced MLKL expression on the apical membrane of PT cells and ameliorated renal function impairment after IRI in both wild-type and Rgmb cKO mice. Taken together, our results suggest that proximal tubular cell necroptosis plays an important role in AKI, and that RGMb protects against AKI by inhibiting MLKL membrane association and necroptosis in proximal tubular cells.
Collapse
|
12
|
Chen F, Hu Q, Huang H, Chen B, Xia Y, Liu W. Follistatin-like protein 1 increases transepithelial resistance in kidney epithelial cells through Akt signaling. Mol Med Rep 2017; 16:4341-4347. [PMID: 28765894 DOI: 10.3892/mmr.2017.7113] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2016] [Accepted: 05/24/2017] [Indexed: 11/06/2022] Open
Abstract
Tight junctions are intercellular junctional structures that control paracellular permeability across epithelial cell sheets, and serve as a barrier to the intramembranic diffusion of components between apical and basolateral cell membrane domains. Follistatin‑like protein 1 (FSTL1) has been reported to promote cellular metabolism and survival. FSTL1 has been revealed to be highly expressed in adult kidney tissues, and high FSTL1 levels have been reported in mouse and human serum samples; however, the roles of FSTL1 in the regulation of kidney function remain to be elucidated. In the present study, FSTL1 was demonstrated to increase the transepithelial electrical resistance in mouse inner medullary collecting duct (mIMCD3) cells. The molecular mechanisms underlying the effects of FSTL1 were also investigated and the results suggested that FSTL1 may exert its actions through the modulation of Akt signaling. In addition, FSTL1 was revealed to produce no effect on the migratory capabilities of mIMCD3 cells. The results of the present study suggested that FSTL1 may facilitate the formation of tight junctions and regulate their function in renal tubular epithelia.
Collapse
Affiliation(s)
- Fei Chen
- Department of Nephrology, The First People's Hospital of Yunnan, Kunming University of Sciences and Technology, Kunming, Yunnan 650032, P.R. China
| | - Qiang Hu
- Department of Emergency Medicine, The Second Affiliated Hospital, Kunming Medical University, Kunming, Yunnan 650101, P.R. China
| | - Huihui Huang
- School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong, SAR, P.R. China
| | - Binbin Chen
- School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong, SAR, P.R. China
| | - Yin Xia
- School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong, SAR, P.R. China
| | - Wenjing Liu
- School of Medicine, Yunnan University, Kunming, Yunnan 650091, P.R. China
| |
Collapse
|
13
|
Liu J, Wang W, Liu M, Su L, Zhou H, Xia Y, Ran J, Lin HY, Yang B. Repulsive guidance molecule b inhibits renal cyst development through the bone morphogenetic protein signaling pathway. Cell Signal 2016; 28:1842-1851. [DOI: 10.1016/j.cellsig.2016.08.015] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2016] [Revised: 08/25/2016] [Accepted: 08/25/2016] [Indexed: 02/04/2023]
|
14
|
Shi Y, Chen GB, Huang XX, Xiao CX, Wang HH, Li YS, Zhang JF, Li S, Xia Y, Ren JL, Guleng B. Dragon (repulsive guidance molecule b, RGMb) is a novel gene that promotes colorectal cancer growth. Oncotarget 2016; 6:20540-54. [PMID: 26029998 PMCID: PMC4653024 DOI: 10.18632/oncotarget.4110] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2015] [Accepted: 04/21/2015] [Indexed: 12/27/2022] Open
Abstract
Colorectal cancer (CRC) is one of the most commonly diagnosed cancers and a major cause of cancer death. However, the molecular mechanisms underlying CRC initiation, growth and metastasis are poorly understood. Dragon (RGMb), a member of the repulsive guidance molecule (RGM) family, has been recently identified as a co-receptor for bone morphogenetic protein (BMP) signaling, but the role of Dragon in CRC development is undefined. Here, we show that Dragon expression was increased in colon cancer tissues compared to control tissues in CAC mouse model and in human patients. Dragon promoted proliferation of CT26.WT and CMT93 colon cancer cells and accelerated tumor growth in the xenograft mouse model. Dragon's action on colon cancer development was mediated via the BMP4-Smad1/5/8 and Erk1/2 pathways. Therefore, our results have revealed that Dragon is a novel gene that promotes CRC growth through the BMP pathway. Dragon may be exploited as a potential therapeutic target for CRC treatment.
Collapse
Affiliation(s)
- Ying Shi
- Department of Gastroenterology, Zhongshan Hospital, Xiamen University, Xiamen, Fujian Province, China
| | - Guo-Bin Chen
- Department of Gastroenterology, Zhongshan Hospital, Xiamen University, Xiamen, Fujian Province, China
| | - Xiao-Xiao Huang
- Department of Gastroenterology, Zhongshan Hospital, Xiamen University, Xiamen, Fujian Province, China
| | - Chuan-Xing Xiao
- Department of Gastroenterology, Zhongshan Hospital, Xiamen University, Xiamen, Fujian Province, China
| | - Huan-Huan Wang
- Department of Gastroenterology, Zhongshan Hospital, Xiamen University, Xiamen, Fujian Province, China
| | - Ye-Sen Li
- Department of Nuclear Medicine, The First Affiliated Hospital of Xiamen University, Xiamen, Fujian Province, China.,Center for Molecular Imaging and Translational Medicine, School of Public Health, Xiamen University, Xiamen, Fujian Province, China
| | - Jin-Fang Zhang
- School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Shatin, N.T., Hong Kong, China
| | - Shao Li
- MOE Key Laboratory of Bioinformatics, Tsinghua University, Beijing, China
| | - Yin Xia
- School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Shatin, N.T., Hong Kong, China.,School of Biomedical Sciences Core Laboratory, The Chinese University of Hong Kong Shenzhen Research Institute, Shenzhen, China
| | - Jian-Lin Ren
- Department of Gastroenterology, Zhongshan Hospital, Xiamen University, Xiamen, Fujian Province, China
| | - Bayasi Guleng
- Department of Gastroenterology, Zhongshan Hospital, Xiamen University, Xiamen, Fujian Province, China.,Faculty of Clinical Medicine, Medical College, Xiamen University, Xiamen, Fujian Province, China.,State Key Laboratory of Cellular Stress Biology, Xiamen University, Xiamen, Fujian Province, China
| |
Collapse
|
15
|
Canali S, Core AB, Zumbrennen-Bullough KB, Merkulova M, Wang CY, Schneyer AL, Pietrangelo A, Babitt JL. Activin B Induces Noncanonical SMAD1/5/8 Signaling via BMP Type I Receptors in Hepatocytes: Evidence for a Role in Hepcidin Induction by Inflammation in Male Mice. Endocrinology 2016; 157:1146-62. [PMID: 26735394 PMCID: PMC4769363 DOI: 10.1210/en.2015-1747] [Citation(s) in RCA: 86] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Induction of the iron regulatory hormone hepcidin contributes to the anemia of inflammation. Bone morphogenetic protein 6 (BMP6) signaling is a central regulator of hepcidin expression in the liver. Recently, the TGF-β/BMP superfamily member activin B was implicated in hepcidin induction by inflammation via noncanonical SMAD1/5/8 signaling, but its mechanism of action and functional significance in vivo remain uncertain. Here, we show that low concentrations of activin B, but not activin A, stimulate prolonged SMAD1/5/8 signaling and hepcidin expression in liver cells to a similar degree as canonical SMAD2/3 signaling, and with similar or modestly reduced potency compared with BMP6. Activin B stimulates hepcidin via classical activin type II receptors ACVR2A and ACVR2B, noncanonical BMP type I receptors activin receptor-like kinase 2 and activin receptor-like kinase 3, and SMAD5. The coreceptor hemojuvelin binds to activin B and facilitates activin B-SMAD1/5/8 signaling. Activin B-SMAD1/5/8 signaling has some selectivity for hepatocyte-derived cells and is not enabled by hemojuvelin in other cell types. Liver activin B mRNA expression is up-regulated in multiple mouse models of inflammation associated with increased hepcidin and hypoferremia, including lipopolysaccharide, turpentine, and heat-killed Brucella abortus models. Finally, the activin inhibitor follistatin-315 blunts hepcidin induction by lipopolysaccharide or B. abortus in mice. Our data elucidate a novel mechanism for noncanonical SMAD activation and support a likely functional role for activin B in hepcidin stimulation during inflammation in vivo.
Collapse
Affiliation(s)
- Susanna Canali
- Program in Anemia Signaling Research (S.C., A.B.C., K.B.Z.-B., M.M., C.-Y.W., J.L.B.), Division of Nephrology, Program in Membrane Biology, Center for Systems Biology, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts 02114; Center for Hemochromatosis (S.C., A.P.), University Hospital of Modena and Reggio Emilia, Modena Italy 41124; and Department of Veterinary and Animal Science (A.S.), University of Massachusetts Amherst, Amherst, Massachusetts 01003
| | - Amanda B Core
- Program in Anemia Signaling Research (S.C., A.B.C., K.B.Z.-B., M.M., C.-Y.W., J.L.B.), Division of Nephrology, Program in Membrane Biology, Center for Systems Biology, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts 02114; Center for Hemochromatosis (S.C., A.P.), University Hospital of Modena and Reggio Emilia, Modena Italy 41124; and Department of Veterinary and Animal Science (A.S.), University of Massachusetts Amherst, Amherst, Massachusetts 01003
| | - Kimberly B Zumbrennen-Bullough
- Program in Anemia Signaling Research (S.C., A.B.C., K.B.Z.-B., M.M., C.-Y.W., J.L.B.), Division of Nephrology, Program in Membrane Biology, Center for Systems Biology, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts 02114; Center for Hemochromatosis (S.C., A.P.), University Hospital of Modena and Reggio Emilia, Modena Italy 41124; and Department of Veterinary and Animal Science (A.S.), University of Massachusetts Amherst, Amherst, Massachusetts 01003
| | - Maria Merkulova
- Program in Anemia Signaling Research (S.C., A.B.C., K.B.Z.-B., M.M., C.-Y.W., J.L.B.), Division of Nephrology, Program in Membrane Biology, Center for Systems Biology, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts 02114; Center for Hemochromatosis (S.C., A.P.), University Hospital of Modena and Reggio Emilia, Modena Italy 41124; and Department of Veterinary and Animal Science (A.S.), University of Massachusetts Amherst, Amherst, Massachusetts 01003
| | - Chia-Yu Wang
- Program in Anemia Signaling Research (S.C., A.B.C., K.B.Z.-B., M.M., C.-Y.W., J.L.B.), Division of Nephrology, Program in Membrane Biology, Center for Systems Biology, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts 02114; Center for Hemochromatosis (S.C., A.P.), University Hospital of Modena and Reggio Emilia, Modena Italy 41124; and Department of Veterinary and Animal Science (A.S.), University of Massachusetts Amherst, Amherst, Massachusetts 01003
| | - Alan L Schneyer
- Program in Anemia Signaling Research (S.C., A.B.C., K.B.Z.-B., M.M., C.-Y.W., J.L.B.), Division of Nephrology, Program in Membrane Biology, Center for Systems Biology, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts 02114; Center for Hemochromatosis (S.C., A.P.), University Hospital of Modena and Reggio Emilia, Modena Italy 41124; and Department of Veterinary and Animal Science (A.S.), University of Massachusetts Amherst, Amherst, Massachusetts 01003
| | - Antonello Pietrangelo
- Program in Anemia Signaling Research (S.C., A.B.C., K.B.Z.-B., M.M., C.-Y.W., J.L.B.), Division of Nephrology, Program in Membrane Biology, Center for Systems Biology, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts 02114; Center for Hemochromatosis (S.C., A.P.), University Hospital of Modena and Reggio Emilia, Modena Italy 41124; and Department of Veterinary and Animal Science (A.S.), University of Massachusetts Amherst, Amherst, Massachusetts 01003
| | - Jodie L Babitt
- Program in Anemia Signaling Research (S.C., A.B.C., K.B.Z.-B., M.M., C.-Y.W., J.L.B.), Division of Nephrology, Program in Membrane Biology, Center for Systems Biology, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts 02114; Center for Hemochromatosis (S.C., A.P.), University Hospital of Modena and Reggio Emilia, Modena Italy 41124; and Department of Veterinary and Animal Science (A.S.), University of Massachusetts Amherst, Amherst, Massachusetts 01003
| |
Collapse
|
16
|
Meng C, Liu W, Huang H, Wang Y, Chen B, Freeman GJ, Schneyer A, Lin HY, Xia Y. Repulsive Guidance Molecule b (RGMb) Is Dispensable for Normal Gonadal Function in Mice. Biol Reprod 2016; 94:78. [PMID: 26911425 DOI: 10.1095/biolreprod.115.135921] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2015] [Accepted: 02/11/2016] [Indexed: 12/22/2022] Open
Abstract
Bone morphogenetic protein (BMP) signaling plays an important role in spermatogenesis and follicle development. Our previous studies have shown that repulsive guidance molecule b (RGMb, also known as Dragon) is a coreceptor that enhances BMP2 and BMP4 signaling in several cell types and that RGMb is expressed in spermatocytes and spermatids in the testis and in oocytes of the secondary follicles in the ovary. Here, we demonstrated that specific deletion of Rgmb in germ cells in the testis and ovary did not alter Smad1/5/8 phosphorylation, gonadal structures, and fertility. In addition, ovaries from postnatal global Rgmb knockout mice showed similar structures to the wild-type ovaries. Our results suggest that RGMb is not essential for normal gonadal function.
Collapse
Affiliation(s)
- Chenling Meng
- Key Laboratory for Regenerative Medicine, Ministry of Education, School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong, China
| | - Wenjing Liu
- Key Laboratory for Regenerative Medicine, Ministry of Education, School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong, China
| | - Huihui Huang
- Key Laboratory for Regenerative Medicine, Ministry of Education, School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong, China
| | - Yang Wang
- Key Laboratory for Regenerative Medicine, Ministry of Education, School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong, China
| | - Binbin Chen
- Key Laboratory for Regenerative Medicine, Ministry of Education, School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong, China
| | - Gordon J Freeman
- Department of Medical Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, Massachusetts
| | - Alan Schneyer
- Pioneer Valley Life Science Institute and Department of Veterinary and Animal Science, University of Massachusetts-Amherst, Amherst, Massachusetts
| | - Herbert Y Lin
- Program in Membrane Biology, Center for Systems Biology, Department of Medicine, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts
| | - Yin Xia
- Key Laboratory for Regenerative Medicine, Ministry of Education, School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong, China School of Biomedical Sciences Core Laboratory, The Chinese University of Hong Kong Shenzhen Research Institute, Shenzhen, China
| |
Collapse
|
17
|
Meng C, Guo N, Wei Q, Shi F, Schneyer AL, Xia Y, Mao D. Expression of repulsive guidance molecule b (RGMb) in the uterus and ovary during the estrous cycle in rats. Acta Histochem 2014; 116:1231-6. [PMID: 25085051 DOI: 10.1016/j.acthis.2014.07.006] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2014] [Revised: 07/12/2014] [Accepted: 07/13/2014] [Indexed: 10/25/2022]
Abstract
Repulsive guidance molecule b (RGMb; a.k.a. Dragon), initially identified in the embryonic dorsal root ganglion, is the first member of the RGM family shown to enhance bone morphogenetic protein (BMP) signaling by acting as a BMP co-receptor. BMP signaling has been demonstrated to play an important role in the reproductive organs. Our previous study found that RGMb was expressed in the reproductive axis, but whether RGMb expression in reproductive organs changes across the estrous cycle remains unknown. Here, we show in the rat that RGMb mRNA expression in the uterus was significantly higher during metesterus and diestrus than during proestrus and estrus. Western blotting indicated that RGMb protein was significantly lower during estrus compared with the other three stages. Immunohistochemistry revealed that RGMb protein was mainly localized to the uterine luminal and glandular epithelial cells of the endometrium. RGMb mRNA and protein in the ovary remained unchanged during the estrous cycle. RGMb protein was expressed in the oocytes of all follicles. Weak staining for RGMb protein was also found in corpora lutea. RGMb was not detected in granulosa cells and stromal cells. Taken together, RGMb expression in the uterus and ovary across the estrus cycle demonstrate that RGMb may be involved in the regulation of uterine function, follicular development as well as luteal activity.
Collapse
|
18
|
Core AB, Canali S, Babitt JL. Hemojuvelin and bone morphogenetic protein (BMP) signaling in iron homeostasis. Front Pharmacol 2014; 5:104. [PMID: 24860505 PMCID: PMC4026703 DOI: 10.3389/fphar.2014.00104] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2014] [Accepted: 04/21/2014] [Indexed: 12/13/2022] Open
Abstract
Mutations in hemojuvelin (HJV) are the most common cause of the juvenile-onset form of the iron overload disorder hereditary hemochromatosis. The discovery that HJV functions as a co-receptor for the bone morphogenetic protein (BMP) family of signaling molecules helped to identify this signaling pathway as a central regulator of the key iron hormone hepcidin in the control of systemic iron homeostasis. This review highlights recent work uncovering the mechanism of action of HJV and the BMP-SMAD signaling pathway in regulating hepcidin expression in the liver, as well as additional studies investigating possible extra-hepatic functions of HJV. This review also explores the interaction between HJV, the BMP-SMAD signaling pathway and other regulators of hepcidin expression in systemic iron balance.
Collapse
Affiliation(s)
- Amanda B Core
- Division of Nephrology, Program in Membrane Biology, Center for Systems Biology, Massachusetts General Hospital, Harvard Medical School, Program in Anemia Signaling Research Boston, MA, USA
| | - Susanna Canali
- Division of Nephrology, Program in Membrane Biology, Center for Systems Biology, Massachusetts General Hospital, Harvard Medical School, Program in Anemia Signaling Research Boston, MA, USA
| | - Jodie L Babitt
- Division of Nephrology, Program in Membrane Biology, Center for Systems Biology, Massachusetts General Hospital, Harvard Medical School, Program in Anemia Signaling Research Boston, MA, USA
| |
Collapse
|
19
|
Holtzhausen A, Golzio C, How T, Lee YH, Schiemann WP, Katsanis N, Blobe GC. Novel bone morphogenetic protein signaling through Smad2 and Smad3 to regulate cancer progression and development. FASEB J 2013; 28:1248-67. [PMID: 24308972 DOI: 10.1096/fj.13-239178] [Citation(s) in RCA: 75] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The bone morphogenetic protein (BMP) signaling pathways have important roles in embryonic development and cellular homeostasis, with aberrant BMP signaling resulting in a broad spectrum of human disease. We report that BMPs unexpectedly signal through the canonical transforming growth factor β (TGF-β)-responsive Smad2 and Smad3. BMP-induced Smad2/3 signaling occurs preferentially in embryonic cells and transformed cells. BMPs signal to Smad2/3 by stimulating complex formation between the BMP-binding TGF-β superfamily receptors, activin receptor-like kinase (ALK)3/6, and the Smad2/3 phosphorylating receptors ALK5/7. BMP signaling through Smad2 mediates, in part, dorsoventral axis patterning in zebrafish embryos, whereas BMP signaling through Smad3 facilitates cancer cell invasion. Consistent with increased BMP-mediated Smad2/3 signaling during cancer progression, Smad1/5 and Smad 2/3 signaling converge in human cancer specimens. Thus, the signaling mechanisms used by BMPs and TGF-β superfamily receptors are broader than previously appreciated.
Collapse
Affiliation(s)
- Alisha Holtzhausen
- 1Duke University Medical Center, 450 Research Drive, LSRC B354, Box 91004, Durham, NC 27708, USA.
| | | | | | | | | | | | | |
Collapse
|
20
|
Liu W, Li X, Zhao Y, Meng XM, Wan C, Yang B, Lan HY, Lin HY, Xia Y. Dragon (repulsive guidance molecule RGMb) inhibits E-cadherin expression and induces apoptosis in renal tubular epithelial cells. J Biol Chem 2013; 288:31528-39. [PMID: 24052264 DOI: 10.1074/jbc.m113.517573] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Dragon is one of the three members of the repulsive guidance molecule (RGM) family, i.e. RGMa, RGMb (Dragon), and RGMc (hemojuvelin). We previously identified the RGM members as bone morphogenetic protein (BMP) co-receptors that enhance BMP signaling. Our previous studies found that Dragon is highly expressed in the tubular epithelial cells of mouse kidneys. However, the roles of Dragon in renal epithelial cells are yet to be defined. We now show that overexpression of Dragon increased cell death induced by hypoxia in association with increased cleaved poly(ADP-ribose) polymerase and cleaved caspase-3 levels in mouse inner medullary collecting duct (IMCD3) cells. Dragon also inhibited E-cadherin expression but did not affect epithelial-to-mesenchymal transition induced by TGF-β in IMCD3 cells. Previous studies suggest that the three RGM members can function as ligands for the receptor neogenin. Interestingly, our present study demonstrates that the Dragon actions on apoptosis and E-cadherin expression in IMCD3 cells were mediated by the neogenin receptor but not through the BMP pathway. Dragon expression in the kidney was up-regulated by unilateral ureteral obstruction in mice. Compared with wild-type mice, heterozygous Dragon knock-out mice exhibited 45-66% reduction in Dragon mRNA expression, decreased epithelial apoptosis, and increased tubular E-cadherin expression and had attenuated tubular injury after unilateral ureteral obstruction. Our results suggest that Dragon may impair tubular epithelial integrity and induce epithelial apoptosis both in vitro and in vivo.
Collapse
Affiliation(s)
- Wenjing Liu
- From the Key Laboratory for Regenerative Medicine, Ministry of Education, School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong, China
| | | | | | | | | | | | | | | | | |
Collapse
|
21
|
Van der Hauwaert C, Savary G, Gnemmi V, Glowacki F, Pottier N, Bouillez A, Maboudou P, Zini L, Leroy X, Cauffiez C, Perrais M, Aubert S. Isolation and characterization of a primary proximal tubular epithelial cell model from human kidney by CD10/CD13 double labeling. PLoS One 2013; 8:e66750. [PMID: 23799132 PMCID: PMC3682988 DOI: 10.1371/journal.pone.0066750] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2012] [Accepted: 05/11/2013] [Indexed: 11/27/2022] Open
Abstract
Renal proximal tubular epithelial cells play a central role in renal physiology and are among the cell types most sensitive to ischemia and xenobiotic nephrotoxicity. In order to investigate the molecular and cellular mechanisms underlying the pathophysiology of kidney injuries, a stable and well-characterized primary culture model of proximal tubular cells is required. An existing model of proximal tubular cells is hampered by the cellular heterogeneity of kidney; a method based on cell sorting for specific markers must therefore be developed. In this study, we present a primary culture model based on the mechanical and enzymatic dissociation of healthy tissue obtained from nephrectomy specimens. Renal epithelial cells were sorted using co-labeling for CD10 and CD13, two renal proximal tubular epithelial markers, by flow cytometry. Their purity, phenotypic stability and functional properties were evaluated over several passages. Our results demonstrate that CD10/CD13 double-positive cells constitute a pure, functional and stable proximal tubular epithelial cell population that displays proximal tubule markers and epithelial characteristics over the long term, whereas cells positive for either CD10 or CD13 alone appear to be heterogeneous. In conclusion, this study describes a method for establishing a robust renal proximal tubular epithelial cell model suitable for further experimentation.
Collapse
Affiliation(s)
- Cynthia Van der Hauwaert
- EA4483, Département de Biochimie et Biologie Moléculaire, Faculté de Médecine de Lille, Pôle Recherche, Lille, France
| | - Grégoire Savary
- EA4483, Département de Biochimie et Biologie Moléculaire, Faculté de Médecine de Lille, Pôle Recherche, Lille, France
| | - Viviane Gnemmi
- Institut National de la Santé et de la Recherche Médicale, U837, Centre de Recherche Jean-Pierre Aubert, Equipe 5 Mucines, Différentiation et Cancérogenèse Épithéliales, Lille, France
- Service d'Anatomie Pathologique, Centre de Biologie et Pathologie, CHRU Lille, Lille, France
- Faculté de Médecine de Lille, Université Lille 2, Lille, France
| | - François Glowacki
- EA4483, Département de Biochimie et Biologie Moléculaire, Faculté de Médecine de Lille, Pôle Recherche, Lille, France
- Faculté de Médecine de Lille, Université Lille 2, Lille, France
- Service de Néphrologie, Hôpital Huriez, CHRU Lille, Lille, France
| | - Nicolas Pottier
- EA4483, Département de Biochimie et Biologie Moléculaire, Faculté de Médecine de Lille, Pôle Recherche, Lille, France
- Faculté de Médecine de Lille, Université Lille 2, Lille, France
| | - Audrey Bouillez
- Institut National de la Santé et de la Recherche Médicale, U837, Centre de Recherche Jean-Pierre Aubert, Equipe 5 Mucines, Différentiation et Cancérogenèse Épithéliales, Lille, France
| | - Patrice Maboudou
- Service de Biochimie, Centre de Biologie et Pathologie, CHRU Lille, Lille, France
| | - Laurent Zini
- Institut National de la Santé et de la Recherche Médicale, U837, Centre de Recherche Jean-Pierre Aubert, Equipe 5 Mucines, Différentiation et Cancérogenèse Épithéliales, Lille, France
- Faculté de Médecine de Lille, Université Lille 2, Lille, France
- Service d'Urologie, Hôpital Huriez, CHRU Lille, Lille, France
| | - Xavier Leroy
- Institut National de la Santé et de la Recherche Médicale, U837, Centre de Recherche Jean-Pierre Aubert, Equipe 5 Mucines, Différentiation et Cancérogenèse Épithéliales, Lille, France
- Service d'Anatomie Pathologique, Centre de Biologie et Pathologie, CHRU Lille, Lille, France
- Faculté de Médecine de Lille, Université Lille 2, Lille, France
| | - Christelle Cauffiez
- EA4483, Département de Biochimie et Biologie Moléculaire, Faculté de Médecine de Lille, Pôle Recherche, Lille, France
- Faculté de Médecine de Lille, Université Lille 2, Lille, France
| | - Michaël Perrais
- Institut National de la Santé et de la Recherche Médicale, U837, Centre de Recherche Jean-Pierre Aubert, Equipe 5 Mucines, Différentiation et Cancérogenèse Épithéliales, Lille, France
- Faculté de Médecine de Lille, Université Lille 2, Lille, France
| | - Sébastien Aubert
- Institut National de la Santé et de la Recherche Médicale, U837, Centre de Recherche Jean-Pierre Aubert, Equipe 5 Mucines, Différentiation et Cancérogenèse Épithéliales, Lille, France
- Service d'Anatomie Pathologique, Centre de Biologie et Pathologie, CHRU Lille, Lille, France
- Faculté de Médecine de Lille, Université Lille 2, Lille, France
- * E-mail:
| |
Collapse
|
22
|
Saitoh M, Shirakihara T, Fukasawa A, Horiguchi K, Sakamoto K, Sugiya H, Beppu H, Fujita Y, Morita I, Miyazono K, Miyazawa K. Basolateral BMP signaling in polarized epithelial cells. PLoS One 2013; 8:e62659. [PMID: 23675417 PMCID: PMC3652834 DOI: 10.1371/journal.pone.0062659] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2013] [Accepted: 03/25/2013] [Indexed: 11/17/2022] Open
Abstract
Bone morphogenetic proteins (BMPs) regulate various biological processes, mostly mediated by cells of mesenchymal origin. However, the roles of BMPs in epithelial cells are poorly understood. Here, we demonstrate that, in polarized epithelial cells, BMP signals are transmitted from BMP receptor complexes exclusively localized at the basolateral surface of the cell membrane. In addition, basolateral stimulation with BMP increased expression of components of tight junctions and enhanced the transepithelial resistance (TER), counteracting reduction of TER by treatment with TGF-β or an anti-tumor drug. We conclude that BMPs maintain epithelial polarity via intracellular signaling from basolaterally localized BMP receptors.
Collapse
Affiliation(s)
- Masao Saitoh
- Department of Biochemistry, Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi, Chuo, Yamanashi, Japan.
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
23
|
Spatiotemporal expression of repulsive guidance molecules (RGMs) and their receptor neogenin in the mouse brain. PLoS One 2013; 8:e55828. [PMID: 23457482 PMCID: PMC3573027 DOI: 10.1371/journal.pone.0055828] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2012] [Accepted: 01/02/2013] [Indexed: 02/07/2023] Open
Abstract
Neogenin has been implicated in a variety of developmental processes such as neurogenesis, neuronal differentiation, apoptosis, migration and axon guidance. Binding of repulsive guidance molecules (RGMs) to Neogenin inhibits axon outgrowth of different neuronal populations. This effect requires Neogenin to interact with co-receptors of the uncoordinated locomotion-5 (Unc5) family to activate downstream Rho signaling. Although previous studies have reported RGM, Neogenin, and/or Unc5 expression, a systematic comparison of RGM and Neogenin expression in the developing nervous system is lacking, especially at later developmental stages. Furthermore, information on RGM and Neogenin expression at the protein level is limited. To fill this void and to gain further insight into the role of RGM-Neogenin signaling during mouse neural development, we studied the expression of RGMa, RGMb, Neogenin and Unc5A-D using in situ hybridization, immunohistochemistry and RGMa section binding. Expression patterns in the primary olfactory system, cortex, hippocampus, habenula, and cerebellum were studied in more detail. Characteristic cell layer-specific expression patterns were detected for RGMa, RGMb, Neogenin and Unc5A-D. Furthermore, strong expression of RGMa, RGMb and Neogenin protein was found on several major axon tracts such as the primary olfactory projections, anterior commissure and fasciculus retroflexus. These data not only hint at a role for RGM-Neogenin signaling during the development of different neuronal systems, but also suggest that Neogenin partners with different Unc5 family members in different systems. Overall, the results presented here will serve as a framework for further dissection of the role of RGM-Neogenin signaling during neural development.
Collapse
|
24
|
Repulsive guidance molecule (RGM) family proteins exhibit differential binding kinetics for bone morphogenetic proteins (BMPs). PLoS One 2012; 7:e46307. [PMID: 23029472 PMCID: PMC3459908 DOI: 10.1371/journal.pone.0046307] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2012] [Accepted: 08/29/2012] [Indexed: 11/30/2022] Open
Abstract
Bone morphogenetic proteins (BMPs) are members of the transforming growth factor beta superfamily that exert their effects via type I and type II serine threonine kinase receptors and the SMAD intracellular signaling pathway to regulate diverse biologic processes. Recently, we discovered that the repulsive guidance molecule (RGM) family, including RGMA, RGMB, and RGMC/hemojuvelin (HJV), function as co-receptors that enhance cellular responses to BMP ligands. Here, we use surface plasmon resonance to quantitate the binding kinetics of RGM proteins for BMP ligands. We show that among the RGMs, HJV exhibits the highest affinity for BMP6, BMP5, and BMP7 with KD 8.1, 17, and 20 nM respectively, versus 28, 33, and 166 nM for RGMB, and 55, 83, and 63 nM for RGMA. Conversely, RGMB exhibits preferential binding to BMP4 and BMP2 with KD 2.6 and 5.5 nM respectively, versus 4.5 and 9.4 nM for HJV, and 14 and 22 nM for RGMA, while RGMA exhibits the lowest binding affinity for most BMPs tested. Among the BMP ligands, RGMs exhibit the highest relative affinity for BMP4 and the lowest relative affinity for BMP7, while none of the RGMs bind to BMP9. Thus, RGMs exhibit preferential binding for distinct subsets of BMP ligands. The preferential binding of HJV for BMP6 is consistent with the functional role of HJV and BMP6 in regulating systemic iron homeostasis. Our data may help explain the mechanism by which BMPs exert cell-context specific effects via a limited number of type I and type II receptors.
Collapse
|
25
|
The BMP coreceptor RGMb promotes while the endogenous BMP antagonist noggin reduces neurite outgrowth and peripheral nerve regeneration by modulating BMP signaling. J Neurosci 2012; 31:18391-400. [PMID: 22171041 DOI: 10.1523/jneurosci.4550-11.2011] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Repulsive guidance molecule b (RGMb) is a bone morphogenetic protein (BMP) coreceptor and sensitizer of BMP signaling, highly expressed in adult dorsal root ganglion (DRG) sensory neurons. We used a murine RGMb knock-out to gain insight into the physiological role of RGMb in the DRG, and address whether RGMb-mediated modulation of BMP signaling influences sensory axon regeneration. No evidence for altered development of the PNS and CNS was detected in RGMb(-/-) mice. However, both cultured neonatal whole DRG explants and dissociated DRG neurons from RGMb(-/-) mice exhibited significantly fewer and shorter neurites than those from wild-type littermates, a phenomenon that could be fully rescued by BMP-2. Moreover, Noggin, an endogenous BMP signaling antagonist, inhibited neurite outgrowth in wild-type DRG explants from naive as well as nerve injury-preconditioned mice. Noggin is downregulated in the DRG after nerve injury, and its expression is highly correlated and inversely associated with the known regeneration-associated genes, which are induced in the DRG by peripheral axonal injury. We show that diminished BMP signaling in vivo, achieved either through RGMb deletion or BMP inhibition with Noggin, retarded early axonal regeneration after sciatic nerve crush injury. Our data suggest a positive modulatory contribution of RGMb and BMP signaling to neurite extension in vitro and early axonal regrowth after nerve injury in vivo and a negative effect of Noggin.
Collapse
|
26
|
Leeuwis JW, Nguyen TQ, Chuva de Sousa Lopes SM, van der Giezen DM, van der Ven K, Rouw PJH, Offerhaus GJA, Mummery CL, Goldschmeding R. Direct visualization of Smad1/5/8-mediated transcriptional activity identifies podocytes and collecting ducts as major targets of BMP signalling in healthy and diseased kidneys. J Pathol 2011; 224:121-32. [DOI: 10.1002/path.2844] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2010] [Revised: 11/30/2010] [Accepted: 12/14/2010] [Indexed: 11/10/2022]
|
27
|
Nie X, Xu J, El-Hashash A, Xu PX. Six1 regulates Grem1 expression in the metanephric mesenchyme to initiate branching morphogenesis. Dev Biol 2011; 352:141-51. [PMID: 21281623 DOI: 10.1016/j.ydbio.2011.01.027] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2010] [Revised: 01/18/2011] [Accepted: 01/22/2011] [Indexed: 01/17/2023]
Abstract
Urinary tract morphogenesis requires subdivision of the ureteric bud (UB) into the intra-renal collecting system and the extra-renal ureter, by responding to signals in its surrounding mesenchyme. BMP4 is a mesenchymal regulator promoting ureter development, while GREM1 is necessary to negatively regulate BMP4 activity to induce UB branching. However, the mechanisms that regulate the GREM1-BMP4 signaling are unknown. Previous studies have shown that Six1-deficient mice lack kidneys, but form ureters. Here, we show that the tip cells of Six1(-/-) UB fail to form an ampulla for branching. Instead, the UB elongates within Tbx18- and Bmp4-expressing mesenchyme. We find that the expression of Grem1 in the metanephric mesenchyme (MM) is Six1-dependent. Treatment of Six1(-/-) kidney rudiments with GREM1 protein restores ampulla formation and branching morphogenesis. Furthermore, we demonstrate that genetic reduction of BMP4 levels in Six1(-/-) (Six1(-/-); Bmp4(+/-)) embryos restores urinary tract morphogenesis and kidney formation. This study uncovers an essential function for Six1 in the MM as an upstream regulator of Grem1 in initiating branching morphogenesis.
Collapse
Affiliation(s)
- Xuguang Nie
- Department of Genetics and Genomic Sciences, Mount Sinai School of Medicine of NYU, New York, NY 10029, USA
| | | | | | | |
Collapse
|
28
|
Xia Y, Cortez-Retamozo V, Niederkofler V, Salie R, Chen S, Samad TA, Hong CC, Arber S, Vyas JM, Weissleder R, Pittet MJ, Lin HY. Dragon (repulsive guidance molecule b) inhibits IL-6 expression in macrophages. THE JOURNAL OF IMMUNOLOGY 2010; 186:1369-76. [PMID: 21187450 DOI: 10.4049/jimmunol.1002047] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Repulsive guidance molecule (RGM) family members RGMa, RGMb/Dragon, and RGMc/hemojuvelin were found recently to act as bone morphogenetic protein (BMP) coreceptors that enhance BMP signaling activity. Although our previous studies have shown that hemojuvelin regulates hepcidin expression and iron metabolism through the BMP pathway, the role of the BMP signaling mediated by Dragon remains largely unknown. We have shown previously that Dragon is expressed in neural cells, germ cells, and renal epithelial cells. In this study, we demonstrate that Dragon is highly expressed in macrophages. Studies with RAW264.7 and J774 macrophage cell lines reveal that Dragon negatively regulates IL-6 expression in a BMP ligand-dependent manner via the p38 MAPK and Erk1/2 pathways but not the Smad1/5/8 pathway. We also generated Dragon knockout mice and found that IL-6 is upregulated in macrophages and dendritic cells derived from whole lung tissue of these mice compared with that in respective cells derived from wild-type littermates. These results indicate that Dragon is an important negative regulator of IL-6 expression in immune cells and that Dragon-deficient mice may be a useful model for studying immune and inflammatory disorders.
Collapse
Affiliation(s)
- Yin Xia
- Center for Systems Biology, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114, USA.
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
29
|
Tian C, Sen D, Shi H, Foehr ML, Plavskin Y, Vatamaniuk OK, Liu J. The RGM protein DRAG-1 positively regulates a BMP-like signaling pathway in Caenorhabditis elegans. Development 2010; 137:2375-84. [PMID: 20534671 DOI: 10.1242/dev.051615] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The bone morphogenetic protein (BMP) signaling pathway regulates multiple developmental and homeostatic processes. Mutations in the pathway can cause a variety of somatic and hereditary disorders in humans. Multiple levels of regulation, including extracellular regulation, ensure proper spatiotemporal control of BMP signaling in the right cellular context. We have identified a modulator of the BMP-like Sma/Mab pathway in C. elegans called DRAG-1. DRAG-1 is the sole member of the repulsive guidance molecule (RGM) family of proteins in C. elegans, and is crucial in regulating body size and mesoderm development. Using a combination of molecular genetic and biochemical analyses, we demonstrate that DRAG-1 is a membrane-associated protein that functions at the ligand-receptor level to modulate the Sma/Mab pathway in a cell-type-specific manner. We further show that DRAG-1 positively modulates this BMP-like pathway by using a novel Sma/Mab-responsive reporter. Our work provides a direct link between RGM proteins and BMP signaling in vivo and a simple and genetically tractable system for mechanistic studies of RGM protein regulation of BMP pathways.
Collapse
Affiliation(s)
- Chenxi Tian
- Department of Molecular Biology and Genetics, 439 Biotechnology Building, Cornell University, Ithaca, NY 14853, USA
| | | | | | | | | | | | | |
Collapse
|