1
|
Earwood R, Ninomiya H, Wang H, Shimada IS, Stroud M, Perez D, Uuganbayar U, Yamada C, Akiyama-Miyoshi T, Stefanovic B, Kato Y. The binding of LARP6 and DNAAF6 in biomolecular condensates influences ciliogenesis of multiciliated cells. J Biol Chem 2024; 300:107373. [PMID: 38762183 PMCID: PMC11208920 DOI: 10.1016/j.jbc.2024.107373] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2023] [Revised: 04/19/2024] [Accepted: 05/03/2024] [Indexed: 05/20/2024] Open
Abstract
Motile cilia on the cell surface produce fluid flows in the body and abnormalities in motile cilia cause primary ciliary dyskinesia. Dynein axonemal assembly factor 6 (DNAAF6), a causative gene of primary ciliary dyskinesia, was isolated as an interacting protein with La ribonucleoprotein 6 (LARP6) that regulates ciliogenesis in multiciliated cells (MCCs). In MCCs of Xenopus embryos, LARP6 and DNAAF6 were colocalized in biomolecular condensates termed dynein axonemal particles and synergized to control ciliogenesis. Moreover, tubulin alpha 1c-like mRNA encoding α-tubulin protein, that is a major component of ciliary axoneme, was identified as a target mRNA regulated by binding LARP6. While DNAAF6 was necessary for high α-tubulin protein expression near the apical side of Xenopus MCCs during ciliogenesis, its mutant, which abolishes binding with LARP6, was unable to restore the expression of α-tubulin protein near the apical side of MCCs in Xenopus DNAAF6 morphant. These results indicated that the binding of LARP6 and DNAAF6 in dynein axonemal particles regulates highly expressed α-tubulin protein near the apical side of Xenopus MCCs during ciliogenesis.
Collapse
Affiliation(s)
- Ryan Earwood
- Department of Biomedical Sciences, Florida State University College of Medicine, Tallahassee, Florida, USA
| | - Hiromasa Ninomiya
- Department of Cell Biology, Nagoya City University, Graduate School of Medical Sciences, Mizuho-ku, Nagoya, Japan
| | - Hao Wang
- Department of Biomedical Sciences, Florida State University College of Medicine, Tallahassee, Florida, USA
| | - Issei S Shimada
- Department of Cell Biology, Nagoya City University, Graduate School of Medical Sciences, Mizuho-ku, Nagoya, Japan
| | - Mia Stroud
- Department of Biomedical Sciences, Florida State University College of Medicine, Tallahassee, Florida, USA
| | - Diana Perez
- Department of Biomedical Sciences, Florida State University College of Medicine, Tallahassee, Florida, USA
| | - Udval Uuganbayar
- Department of Cell Biology, Nagoya City University, Graduate School of Medical Sciences, Mizuho-ku, Nagoya, Japan
| | - Chisato Yamada
- Department of Cell Biology, Nagoya City University, Graduate School of Medical Sciences, Mizuho-ku, Nagoya, Japan
| | - Toru Akiyama-Miyoshi
- Pathogenic Microbe Laboratory, Research Institute, National Center for Global Health and Medicine, Tokyo, Japan
| | - Branko Stefanovic
- Department of Biomedical Sciences, Florida State University College of Medicine, Tallahassee, Florida, USA.
| | - Yoichi Kato
- Department of Biomedical Sciences, Florida State University College of Medicine, Tallahassee, Florida, USA; Department of Cell Biology, Nagoya City University, Graduate School of Medical Sciences, Mizuho-ku, Nagoya, Japan.
| |
Collapse
|
2
|
Meng F, Hua S, Chen X, Meng N, Lan T. Lymph node metastasis related gene BICC1 promotes tumor progression by promoting EMT and immune infiltration in pancreatic cancer. BMC Med Genomics 2023; 16:263. [PMID: 37880742 PMCID: PMC10601354 DOI: 10.1186/s12920-023-01696-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2023] [Accepted: 10/11/2023] [Indexed: 10/27/2023] Open
Abstract
BACKGROUND Pancreatic cancer (PC) is one of the most aggressive abdominal malignancies with a poor prognosis and it is urgent to find effective biomarkers for prediction. Although BICC1 expression is related to the survival, no evidence for its role in PC development has been found. METHODS We used RNA-seq data to screen for molecular markers highly associated with lymph node metastasis. The Cancer Genome Atlas (TCGA) and International Cancer Genome Consortium (ICGC) public databases were used to analyze the expression and prognosis of Differential Expressed Genes (DEGs) in PC. R studio was used for visualization and functional analysis. RESULTS BicC Family RNA Binding Protein 1 (BICC1) was a lymph node metastasis-related DEGs in PC patients. Our study found that BICC1 mRNA levels in the tumor tissue were significantly higher and associated with poorer prognosis. Enrichment analysis found that BICC1 was enriched primarily in the Epithelial Mesenchymal Transition (EMT) pathway. Using the ESTIMATE and CIBERSORT algorithms, we found that BICC1 was related to immune cell infiltration. As a regulator of multiple immune checkpoints, BICC1 was also involved in PC's immune response. CONCLUSIONS BICC1 has the potential to be a new marker in association with lymph node metastasis as well as immune infiltration of PC. In addition to being a prognostic indicator, it may also be a potential therapeutic target.
Collapse
Affiliation(s)
- Feilong Meng
- Minimally invasive Center of Hepatobiliary and Pancreatic surgery, The Second Hospital of Harbin, Harbin, Heilongjiang, China
| | - Shuai Hua
- Hepatobiliary and Pancreatic Surgery, The Second Hospital of Harbin, Harbin, Heilongjiang, China
| | - Xuedong Chen
- Hepatobiliary and Pancreatic Surgery, The Second Hospital of Harbin, Harbin, Heilongjiang, China
| | - Nanfeng Meng
- Department of Hepatopancreatobiliary Surgery, The Second Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang, China
| | - Ting Lan
- Department of Rehabilitation, The Second Hospital of Harbin, Ward A, Harbin, Heilongjiang, China.
| |
Collapse
|
3
|
Cervino AS, Collodel MG, Lopez IA, Roa C, Hochbaum D, Hukriede NA, Cirio MC. Xenopus Ssbp2 is required for embryonic pronephros morphogenesis and terminal differentiation. Sci Rep 2023; 13:16671. [PMID: 37794075 PMCID: PMC10551014 DOI: 10.1038/s41598-023-43662-1] [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: 05/08/2023] [Accepted: 09/27/2023] [Indexed: 10/06/2023] Open
Abstract
The nephron, functional unit of the vertebrate kidney, is specialized in metabolic wastes excretion and body fluids osmoregulation. Given the high evolutionary conservation of gene expression and segmentation patterning between mammalian and amphibian nephrons, the Xenopus laevis pronephric kidney offers a simplified model for studying nephrogenesis. The Lhx1 transcription factor plays several roles during embryogenesis, regulating target genes expression by forming multiprotein complexes with LIM binding protein 1 (Ldb1). However, few Lhx1-Ldb1 cofactors have been identified for kidney organogenesis. By tandem- affinity purification from kidney-induced Xenopus animal caps, we identified single-stranded DNA binding protein 2 (Ssbp2) interacts with the Ldb1-Lhx1 complex. Ssbp2 is expressed in the Xenopus pronephros, and knockdown prevents normal morphogenesis and differentiation of the glomus and the convoluted renal tubules. We demonstrate a role for a member of the Ssbp family in kidney organogenesis and provide evidence of a fundamental function for the Ldb1-Lhx1-Ssbp transcriptional complexes in embryonic development.
Collapse
Affiliation(s)
- Ailen S Cervino
- Facultad de Ciencias Exactas y Naturales, Instituto de Fisiología, Biología Molecular y Neurociencias (IFIBYNE-CONICET), Universidad de Buenos Aires, Ciudad Universitaria Pabellón II, C1428EHA, Buenos Aires, Argentina
| | - Mariano G Collodel
- Facultad de Ciencias Exactas y Naturales, Instituto de Fisiología, Biología Molecular y Neurociencias (IFIBYNE-CONICET), Universidad de Buenos Aires, Ciudad Universitaria Pabellón II, C1428EHA, Buenos Aires, Argentina
| | - Ivan A Lopez
- Facultad de Ciencias Exactas y Naturales, Instituto de Fisiología, Biología Molecular y Neurociencias (IFIBYNE-CONICET), Universidad de Buenos Aires, Ciudad Universitaria Pabellón II, C1428EHA, Buenos Aires, Argentina
| | - Carolina Roa
- Facultad de Ciencias Exactas y Naturales, Instituto de Fisiología, Biología Molecular y Neurociencias (IFIBYNE-CONICET), Universidad de Buenos Aires, Ciudad Universitaria Pabellón II, C1428EHA, Buenos Aires, Argentina
| | - Daniel Hochbaum
- Centro de Estudios Biomédicos, Básicos, Aplicados y Desarrollo (CEBBAD), Universidad Maimónides, Buenos Aires, Argentina
| | - Neil A Hukriede
- Department of Developmental Biology, University of Pittsburgh, Pittsburgh, PA, USA
| | - M Cecilia Cirio
- Facultad de Ciencias Exactas y Naturales, Instituto de Fisiología, Biología Molecular y Neurociencias (IFIBYNE-CONICET), Universidad de Buenos Aires, Ciudad Universitaria Pabellón II, C1428EHA, Buenos Aires, Argentina.
| |
Collapse
|
4
|
Cervino AS, Collodel MG, Lopez IA, Hochbaum D, Hukriede NA, Cirio MC. Xenopus Ssbp2 is required for embryonic pronephros morphogenesis and terminal differentiation. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.04.15.537039. [PMID: 37090653 PMCID: PMC10120741 DOI: 10.1101/2023.04.15.537039] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/25/2023]
Abstract
The nephron, functional unit of the vertebrate kidney, is specialized in metabolic wastes excretion and body fluids osmoregulation. Given the high evolutionary conservation of gene expression and segmentation patterning between mammalian and amphibian nephrons, the Xenopus laevis pronephric kidney offers a simplified model for studying nephrogenesis. The Lhx1 transcription factor plays several roles during embryogenesis, regulating target genes expression by forming multiprotein complexes with LIM binding protein 1 (Ldb1). However, few Lhx1-Ldb1 cofactors have been identified for kidney organogenesis. By tandem-affinity purification from kidney-induced Xenopus animal caps, we identified s ingle- s tranded DNA b inding p rotein 2 (Ssbp2) interacts with the Ldb1-Lhx1 complex. Ssbp2 is expressed in the Xenopus pronephros, and knockdown prevents normal morphogenesis and differentiation of the glomus and the convoluted renal tubules. We demonstrate a role for a member of the Ssbp family in kidney organogenesis and provide evidence of a fundamental function for the Ldb1-Lhx1-Ssbp transcriptional complexes in embryonic development.
Collapse
|
5
|
Grand K, Stoltz M, Rizzo L, Röck R, Kaminski MM, Salinas G, Getwan M, Naert T, Pichler R, Lienkamp SS. HNF1B Alters an Evolutionarily Conserved Nephrogenic Program of Target Genes. J Am Soc Nephrol 2023; 34:412-432. [PMID: 36522156 PMCID: PMC10103355 DOI: 10.1681/asn.2022010076] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2022] [Revised: 10/11/2022] [Accepted: 11/09/2022] [Indexed: 12/23/2022] Open
Abstract
SIGNIFICANCE STATEMENT Mutations in hepatocyte nuclear factor-1 β ( HNF1B ) are the most common monogenic causes of congenital renal malformations. HNF1B is necessary to directly reprogram fibroblasts to induced renal tubule epithelial cells (iRECs) and, as we demonstrate, can induce ectopic pronephric tissue in Xenopus ectodermal organoids. Using these two systems, we analyzed the effect of HNF1B mutations found in patients with cystic dysplastic kidney disease. We found cross-species conserved targets of HNF1B, identified transcripts that are differentially regulated by the patient-specific mutant protein, and functionally validated novel HNF1B targets in vivo . These results highlight evolutionarily conserved transcriptional mechanisms and provide insights into the genetic circuitry of nephrogenesis. BACKGROUND Hepatocyte nuclear factor-1 β (HNF1B) is an essential transcription factor during embryogenesis. Mutations in HNF1B are the most common monogenic causes of congenital cystic dysplastic renal malformations. The direct functional consequences of mutations in HNF1B on its transcriptional activity are unknown. METHODS Direct reprogramming of mouse fibroblasts to induced renal tubular epithelial cells was conducted both with wild-type HNF1B and with patient mutations. HNF1B was expressed in Xenopus ectodermal explants. Transcriptomic analysis by bulk RNA-Seq identified conserved targets with differentially regulated expression by the wild-type or R295C mutant. CRISPR/Cas9 genome editing in Xenopus embryos evaluated transcriptional targets in vivo . RESULTS HNF1B is essential for reprogramming mouse fibroblasts to induced renal tubular epithelial cells and induces development of ectopic renal organoids from pluripotent Xenopus cells. The mutation R295C retains reprogramming and inductive capacity but alters the expression of specific sets of downstream target genes instead of diminishing overall transcriptional activity of HNF1B. Surprisingly, targets associated with polycystic kidney disease were less affected than genes affected in congenital renal anomalies. Cross-species-conserved transcriptional targets were dysregulated in hnf1b CRISPR-depleted Xenopus embryos, confirming their dependence on hnf1b . CONCLUSIONS HNF1B activates an evolutionarily conserved program of target genes that disease-causing mutations selectively disrupt. These findings provide insights into the renal transcriptional network that controls nephrogenesis.
Collapse
Affiliation(s)
- Kelli Grand
- Institute of Anatomy, University of Zurich, Zurich, Switzerland
| | - Martine Stoltz
- The University Medical Center Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Ludovica Rizzo
- Institute of Anatomy, University of Zurich, Zurich, Switzerland
| | - Ruth Röck
- Institute of Anatomy, University of Zurich, Zurich, Switzerland
| | - Michael M. Kaminski
- Berlin Institute for Medical Systems Biology, Max Delbrück Center for Molecular Medicine in the Helmholtz Association, Berlin, Germany
- Department of Nephrology and Medical Intensive Care, Charité Universitätsmedizin Berlin, Berlin, Germany
- Berlin Institute of Health, Berlin, Germany
| | | | - Maike Getwan
- Institute of Anatomy, University of Zurich, Zurich, Switzerland
| | - Thomas Naert
- Institute of Anatomy, University of Zurich, Zurich, Switzerland
| | - Roman Pichler
- The University Medical Center Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Soeren S. Lienkamp
- Institute of Anatomy, University of Zurich, Zurich, Switzerland
- The University Medical Center Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| |
Collapse
|
6
|
Dowdle ME, Kanzler CR, Harder CRK, Moffet S, Walker MN, Sheets MD. Bicaudal-C Post-transcriptional regulator of cell fates and functions. Front Cell Dev Biol 2022; 10:981696. [PMID: 36158189 PMCID: PMC9491823 DOI: 10.3389/fcell.2022.981696] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2022] [Accepted: 08/11/2022] [Indexed: 11/13/2022] Open
Abstract
Bicaudal-C (Bicc1) is an evolutionarily conserved RNA binding protein that functions in a regulatory capacity in a variety of contexts. It was originally identified as a genetic locus in Drosophila that when disrupted resulted in radical changes in early development. In the most extreme phenotypes embryos carrying mutations developed with mirror image duplications of posterior structures and it was this striking phenotype that was responsible for the name Bicaudal. These seminal studies established Bicc1 as an important regulator of Drosophila development. What was not anticipated from the early work, but was revealed subsequently in many different organisms was the broad fundamental impact that Bicc1 proteins have on developmental biology; from regulating cell fates in vertebrate embryos to defects associated with several human disease states. In the following review we present a perspective of Bicc1 focusing primarily on the molecular aspects of its RNA metabolism functions in vertebrate embryos.
Collapse
|
7
|
Abstract
RNA-binding proteins (RBPs) are of fundamental importance for post-transcriptional gene regulation and protein synthesis. They are required for pre-mRNA processing and for RNA transport, degradation and translation into protein, and can regulate every step in the life cycle of their RNA targets. In addition, RBP function can be modulated by RNA binding. RBPs also participate in the formation of ribonucleoprotein complexes that build up macromolecular machineries such as the ribosome and spliceosome. Although most research has focused on mRNA-binding proteins, non-coding RNAs are also regulated and sequestered by RBPs. Functional defects and changes in the expression levels of RBPs have been implicated in numerous diseases, including neurological disorders, muscular atrophy and cancers. RBPs also contribute to a wide spectrum of kidney disorders. For example, human antigen R has been reported to have a renoprotective function in acute kidney injury (AKI) but might also contribute to the development of glomerulosclerosis, tubulointerstitial fibrosis and diabetic kidney disease (DKD), loss of bicaudal C is associated with cystic kidney diseases and Y-box binding protein 1 has been implicated in the pathogenesis of AKI, DKD and glomerular disorders. Increasing data suggest that the modulation of RBPs and their interactions with RNA targets could be promising therapeutic strategies for kidney diseases.
Collapse
|
8
|
Ift88, but not Kif3a, is required for establishment of the periciliary membrane compartment. Biochem Biophys Res Commun 2021; 584:19-25. [PMID: 34753064 DOI: 10.1016/j.bbrc.2021.10.075] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2021] [Accepted: 10/29/2021] [Indexed: 11/22/2022]
Abstract
The primary cilium is a sensory organelle at the cell surface with integral functions in cell signaling. It contains a microtubular axoneme that is rooted in the basal body (BB) and serves as a scaffold for the movement of intraflagellar transport (IFT) particles by Kinesin-2 along the cilium. Ift88, a member of the anterograde moving IFT-B1 complex, as well as the Kinesin-2 subunit Kif3a are required for cilia formation. To facilitate signaling, the cilium restricts the access of molecules to its membrane ("ciliary gate"). This is thought to be mediated by cytoskeletal barriers ("subciliary domains") originating from the BB subdistal/distal appendages, the periciliary membrane compartment (PCMC) as well as the transition fibers and zone (TF/TZ). The PCMC is a poorly characterized membrane domain surrounding the ciliary base with exclusion of certain apical membrane proteins. Here we describe that Ift88, but not Kinesin-2, is required for the establishment of the PCMC in MDCK cells. Likewise, in C. elegans mutants of the Ift88 ortholog osm-5 fail to establish the PCMC, while Kinesin-2 deficient osm-3 mutants form PCMCs normally. Furthermore, disruption of IFT-B1 into two subcomplexes, while disrupting ciliogenesis, does not interfere with PCMC formation. Our findings suggest that cilia are not a prerequisite for the formation of the PCMC, and that separate machineries with partially overlapping functions are required for the establishment of each.
Collapse
|
9
|
Marquez J, Mann N, Arana K, Deniz E, Ji W, Konstantino M, Mis EK, Deshpande C, Jeffries L, McGlynn J, Hugo H, Widmeier E, Konrad M, Tasic V, Morotti R, Baptista J, Ellard S, Lakhani SA, Hildebrandt F, Khokha MK. DLG5 variants are associated with multiple congenital anomalies including ciliopathy phenotypes. J Med Genet 2021; 58:453-464. [PMID: 32631816 PMCID: PMC7785698 DOI: 10.1136/jmedgenet-2019-106805] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2019] [Revised: 05/01/2020] [Accepted: 05/25/2020] [Indexed: 12/21/2022]
Abstract
BACKGROUND Cilia are dynamic cellular extensions that generate and sense signals to orchestrate proper development and tissue homeostasis. They rely on the underlying polarisation of cells to participate in signalling. Cilia dysfunction is a well-known cause of several diseases that affect multiple organ systems including the kidneys, brain, heart, respiratory tract, skeleton and retina. METHODS Among individuals from four unrelated families, we identified variants in discs large 5 (DLG5) that manifested in a variety of pathologies. In our proband, we also examined patient tissues. We depleted dlg5 in Xenopus tropicalis frog embryos to generate a loss-of-function model. Finally, we tested the pathogenicity of DLG5 patient variants through rescue experiments in the frog model. RESULTS Patients with variants of DLG5 were found to have a variety of phenotypes including cystic kidneys, nephrotic syndrome, hydrocephalus, limb abnormalities, congenital heart disease and craniofacial malformations. We also observed a loss of cilia in cystic kidney tissue of our proband. Knockdown of dlg5 in Xenopus embryos recapitulated many of these phenotypes and resulted in a loss of cilia in multiple tissues. Unlike introduction of wildtype DLG5 in frog embryos depleted of dlg5, introduction of DLG5 patient variants was largely ineffective in restoring proper ciliation and tissue morphology in the kidney and brain suggesting that the variants were indeed detrimental to function. CONCLUSION These findings in both patient tissues and Xenopus shed light on how mutations in DLG5 may lead to tissue-specific manifestations of disease. DLG5 is essential for cilia and many of the patient phenotypes are in the ciliopathy spectrum.
Collapse
Affiliation(s)
- Jonathan Marquez
- Pediatric Genomics Discovery Program, Department of Pediatrics and Genetics, Yale University School of Medicine, New Haven, Connecticut, USA
| | - Nina Mann
- Division of Nephrology, Boston Children's Hospital and Harvard Medical School, Boston, Massachusetts, USA
| | - Kathya Arana
- Pediatric Genomics Discovery Program, Department of Pediatrics, Yale University School of Medicine, New Haven, Connecticut, USA
| | - Engin Deniz
- Pediatric Genomics Discovery Program, Department of Pediatrics, Yale University School of Medicine, New Haven, Connecticut, USA
| | - Weizhen Ji
- Pediatric Genomics Discovery Program, Department of Pediatrics, Yale University School of Medicine, New Haven, Connecticut, USA
| | - Monica Konstantino
- Pediatric Genomics Discovery Program, Department of Pediatrics, Yale University School of Medicine, New Haven, Connecticut, USA
| | - Emily K Mis
- Pediatric Genomics Discovery Program, Department of Pediatrics, Yale University School of Medicine, New Haven, Connecticut, USA
| | | | - Lauren Jeffries
- Pediatric Genomics Discovery Program, Department of Pediatrics, Yale University School of Medicine, New Haven, Connecticut, USA
| | - Julie McGlynn
- Department of Obstetrics, Gynecology, and Reproductive Sciences, Yale University School of Medicine, New Haven, Connecticut, USA
| | - Hannah Hugo
- Division of Nephrology, Boston Children's Hospital and Harvard Medical School, Boston, Massachusetts, USA
| | - Eugen Widmeier
- Division of Nephrology, Boston Children's Hospital and Harvard Medical School, Boston, Massachusetts, USA
| | - Martin Konrad
- Department of General Pediatrics, University Hospital Münster, Münster, Germany
| | - Velibor Tasic
- Department of Pediatric Nephrology, University Children's Hospital, Skopje, North Macedonia
| | - Raffaella Morotti
- Department of Pathology, Yale University School of Medicine, New Haven, Connecticut, USA
| | - Julia Baptista
- Exeter Genomics Laboratory, Royal Devon & Exeter NHS Foundation Trust, Exeter, UK
- Institute of Biomedical & Clinical Science, College of Medicine and Health, Exeter, UK
| | - Sian Ellard
- Exeter Genomics Laboratory, Royal Devon & Exeter NHS Foundation Trust, Exeter, UK
- Institute of Biomedical & Clinical Science, College of Medicine and Health, Exeter, UK
| | - Saquib Ali Lakhani
- Pediatric Genomics Discovery Program, Department of Pediatrics, Yale University School of Medicine, New Haven, Connecticut, USA
| | - Friedhelm Hildebrandt
- Division of Nephrology, Boston Children's Hospital and Harvard Medical School, Boston, Massachusetts, USA
| | - Mustafa K Khokha
- Pediatric Genomics Discovery Program, Department of Pediatrics and Genetics, Yale University School of Medicine, New Haven, Connecticut, USA
| |
Collapse
|
10
|
Zhao R, Peng C, Song C, Zhao Q, Rong J, Wang H, Ding W, Wang F, Xie Y. BICC1 as a novel prognostic biomarker in gastric cancer correlating with immune infiltrates. Int Immunopharmacol 2020; 87:106828. [PMID: 32736193 DOI: 10.1016/j.intimp.2020.106828] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2020] [Revised: 07/20/2020] [Accepted: 07/20/2020] [Indexed: 12/24/2022]
Abstract
AIM BicC family RNA-binding protein 1 (BICC1) codes an RNA-binding protein that regulates gene expression and modulates cell proliferation and apoptosis. We aim at investigating the role of BICC1 in gastric carcinogenesis. METHODS BICC1 mRNA expression in gastric cancer (GC) was examined using the Tumor Immune Estimation Resource (TIMER), The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases. Correlations between BICC1 expression and clinicopathological parameters were analyzed. The Gene Expression Profiling Interactive Analysis (GEPIA) and Kaplan-Meier plotter databases were used to examine the clinical prognostic significance of BICC1 in GC. Signaling pathways related to BICC1 expression were identified by gene set enrichment analysis (GSEA). TIMER and CIBERSORT were used to analyze the correlations among BICC1, BICC1-coexpressed genes and tumor-infiltrating immune cells. RESULTS BICC1 was highly expressed in GC and significantly correlated with grade (P = 0.002), TNM stage (P = 0.033), invasion depth (P = 0.001) and vital status (P = 0.009) of GC patients. High BICC1 expression correlated with poor overall survival. The GSEA results showed that cell adhesion-, tumor- and immune- related pathways were significantly enriched in samples with high BICC1 expression. BICC1 and its coexpressed genes were positively related to tumor-infiltrating immune cells and were strongly correlated with tumor-infiltrating macrophages (all r ≥ 0.582, P < 0.0001). The CIBERSORT database revealed that BICC1 correlated with M2 macrophages (P < 0.0001), regulatory T cells (P < 0.0001), resting mast cells (P < 0.0001), activated memory CD4+ T cells (P = 0.002), resting NK cells (P = 0.002), activated dendritic cells (P = 0.002), and follicular helper T cells (P = 0.016). The results from TIMER database confirmed that BICC1 is closely associated with the markers of M2 macrophages and tumor-associated macrophages (all r ≥ 0.5, P < 0.0001). CONCLUSION BICC1 may be a potential prognostic biomarker in GC and correlates with immune infiltrates.
Collapse
Affiliation(s)
- Rulin Zhao
- Department of Gastroenterology, The First Affiliated Hospital of Nanchang University, No. 17, Yongwai Zheng Street, Nanchang 330000, Jiangxi, China
| | - Chao Peng
- Department of Gastroenterology, The First Affiliated Hospital of Nanchang University, No. 17, Yongwai Zheng Street, Nanchang 330000, Jiangxi, China
| | - Conghua Song
- Department of Gastroenterology, The First Affiliated Hospital of Nanchang University, No. 17, Yongwai Zheng Street, Nanchang 330000, Jiangxi, China
| | - Qiaoyun Zhao
- Department of Gastroenterology, The First Affiliated Hospital of Nanchang University, No. 17, Yongwai Zheng Street, Nanchang 330000, Jiangxi, China
| | - Jianfang Rong
- Department of Gastroenterology, The First Affiliated Hospital of Nanchang University, No. 17, Yongwai Zheng Street, Nanchang 330000, Jiangxi, China
| | - Huan Wang
- Department of Gastroenterology, The First Affiliated Hospital of Nanchang University, No. 17, Yongwai Zheng Street, Nanchang 330000, Jiangxi, China
| | - Wenjie Ding
- Department of Gastroenterology, The First Affiliated Hospital of Nanchang University, No. 17, Yongwai Zheng Street, Nanchang 330000, Jiangxi, China; Department of Gastroenterology, The Second Affiliated Hospital of Nanchang University, No. 1, Min de Street, Nanchang 330000, Jiangxi, China
| | - Fangfei Wang
- Department of Gastroenterology, The First Affiliated Hospital of Nanchang University, No. 17, Yongwai Zheng Street, Nanchang 330000, Jiangxi, China
| | - Yong Xie
- Department of Gastroenterology, The First Affiliated Hospital of Nanchang University, No. 17, Yongwai Zheng Street, Nanchang 330000, Jiangxi, China.
| |
Collapse
|
11
|
An Overview of In Vivo and In Vitro Models for Autosomal Dominant Polycystic Kidney Disease: A Journey from 3D-Cysts to Mini-Pigs. Int J Mol Sci 2020; 21:ijms21124537. [PMID: 32630605 PMCID: PMC7352572 DOI: 10.3390/ijms21124537] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2020] [Revised: 06/17/2020] [Accepted: 06/18/2020] [Indexed: 12/24/2022] Open
Abstract
Autosomal dominant polycystic kidney disease (ADPKD) is the most common inheritable cause of end stage renal disease and, as of today, only a single moderately effective treatment is available for patients. Even though ADPKD research has made huge progress over the last decades, the precise disease mechanisms remain elusive. However, a wide variety of cellular and animal models have been developed to decipher the pathophysiological mechanisms and related pathways underlying the disease. As none of these models perfectly recapitulates the complexity of the human disease, the aim of this review is to give an overview of the main tools currently available to ADPKD researchers, as well as their main advantages and limitations.
Collapse
|
12
|
Blackburn ATM, Miller RK. Modeling congenital kidney diseases in Xenopus laevis. Dis Model Mech 2019; 12:12/4/dmm038604. [PMID: 30967415 PMCID: PMC6505484 DOI: 10.1242/dmm.038604] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Congenital anomalies of the kidney and urinary tract (CAKUT) occur in ∼1/500 live births and are a leading cause of pediatric kidney failure. With an average wait time of 3-5 years for a kidney transplant, the need is high for the development of new strategies aimed at reducing the incidence of CAKUT and preserving renal function. Next-generation sequencing has uncovered a significant number of putative causal genes, but a simple and efficient model system to examine the function of CAKUT genes is needed. Xenopus laevis (frog) embryos are well-suited to model congenital kidney diseases and to explore the mechanisms that cause these developmental defects. Xenopus has many advantages for studying the kidney: the embryos develop externally and are easily manipulated with microinjections, they have a functional kidney in ∼2 days, and 79% of identified human disease genes have a verified ortholog in Xenopus. This facilitates high-throughput screening of candidate CAKUT-causing genes. In this Review, we present the similarities between Xenopus and mammalian kidneys, highlight studies of CAKUT-causing genes in Xenopus and describe how common kidney diseases have been modeled successfully in this model organism. Additionally, we discuss several molecular pathways associated with kidney disease that have been studied in Xenopus and demonstrate why it is a useful model for studying human kidney diseases. Summary: Understanding how congenital kidney diseases arise is imperative to their treatment. Using Xenopus as a model will aid in elucidating kidney development and congenital kidney diseases.
Collapse
Affiliation(s)
- Alexandria T M Blackburn
- Pediatric Research Center, Department of Pediatrics, McGovern Medical School, The University of Texas Health Science Center, Houston, TX 77030, USA.,The University of Texas MD Anderson Cancer Center UTHealth Graduate School of Biomedical Sciences, Program in Genetics and Epigenetics, Houston, TX 77030, USA
| | - Rachel K Miller
- Pediatric Research Center, Department of Pediatrics, McGovern Medical School, The University of Texas Health Science Center, Houston, TX 77030, USA .,The University of Texas MD Anderson Cancer Center UTHealth Graduate School of Biomedical Sciences, Program in Genetics and Epigenetics, Houston, TX 77030, USA.,The University of Texas MD Anderson Cancer Center UTHealth Graduate School of Biomedical Sciences, Program in Biochemistry and Cell Biology Houston, Houston, TX 77030, USA.,Department of Genetics, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| |
Collapse
|
13
|
Modeling Renal Disease "On the Fly". BIOMED RESEARCH INTERNATIONAL 2018; 2018:5697436. [PMID: 29955604 PMCID: PMC6000847 DOI: 10.1155/2018/5697436] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/03/2018] [Accepted: 04/17/2018] [Indexed: 12/22/2022]
Abstract
Detoxification is a fundamental function for all living organisms that need to excrete catabolites and toxins to maintain homeostasis. Kidneys are major organs of detoxification that maintain water and electrolyte balance to preserve physiological functions of vertebrates. In insects, the renal function is carried out by Malpighian tubules and nephrocytes. Due to differences in their circulation, the renal systems of mammalians and insects differ in their functional modalities, yet carry out similar biochemical and physiological functions and share extensive genetic and molecular similarities. Evolutionary conservation can be leveraged to model specific aspects of the complex mammalian kidney function in the genetic powerhouse Drosophila melanogaster to study how genes interact in diseased states. Here, we compare the human and Drosophila renal systems and present selected fly disease models.
Collapse
|
14
|
Zhang B, Tran U, Wessely O. Polycystin 1 loss of function is directly linked to an imbalance in G-protein signaling in the kidney. Development 2018. [PMID: 29530879 DOI: 10.1242/dev.158931] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The development of the kidney relies on the establishment and maintenance of a precise tubular diameter of its functional units, the nephrons. This process is disrupted in polycystic kidney disease (PKD), resulting in dilations of the nephron and renal cyst formation. In the course of exploring G-protein-coupled signaling in the Xenopus pronephric kidney, we discovered that loss of the G-protein α subunit, Gnas, results in a PKD phenotype. Polycystin 1, one of the genes mutated in human PKD, encodes a protein resembling a G-protein-coupled receptor. Furthermore, deletion of the G-protein-binding domain present in the intracellular C terminus of polycystin 1 impacts functionality. A comprehensive analysis of all the G-protein α subunits expressed in the Xenopus pronephric kidney demonstrates that polycystin 1 recruits a select subset of G-protein α subunits and that their knockdown - as in the case of Gnas - results in a PKD phenotype. Mechanistically, the phenotype is caused by increased endogenous G-protein β/γ signaling and can be reversed by pharmacological inhibitors as well as knocking down Gnb1. Together, our data support the hypothesis that G proteins are recruited to the intracellular domain of PKD1 and that this interaction is crucial for its function in the kidney.
Collapse
Affiliation(s)
- Bo Zhang
- Cleveland Clinic Foundation, Lerner Research Institute, Department of Cellular and Molecular Medicine, 9500 Euclid Avenue/NC10, Cleveland, OH 44195, USA.,LSU Health Sciences Center, Department of Cell Biology and Anatomy, 1901 Perdido Street, New Orleans, LA 70112, USA
| | - Uyen Tran
- Cleveland Clinic Foundation, Lerner Research Institute, Department of Cellular and Molecular Medicine, 9500 Euclid Avenue/NC10, Cleveland, OH 44195, USA
| | - Oliver Wessely
- Cleveland Clinic Foundation, Lerner Research Institute, Department of Cellular and Molecular Medicine, 9500 Euclid Avenue/NC10, Cleveland, OH 44195, USA
| |
Collapse
|
15
|
Feng S, Streets AJ, Nesin V, Tran U, Nie H, Onopiuk M, Wessely O, Tsiokas L, Ong ACM. The Sorting Nexin 3 Retromer Pathway Regulates the Cell Surface Localization and Activity of a Wnt-Activated Polycystin Channel Complex. J Am Soc Nephrol 2017; 28:2973-2984. [PMID: 28620080 PMCID: PMC5619965 DOI: 10.1681/asn.2016121349] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2016] [Accepted: 05/07/2017] [Indexed: 02/04/2023] Open
Abstract
Autosomal dominant polycystic kidney disease (ADPKD) is caused by inactivating mutations in PKD1 (85%) or PKD2 (15%). The ADPKD proteins encoded by these genes, polycystin-1 (PC1) and polycystin-2 (PC2), form a plasma membrane receptor-ion channel complex. However, the mechanisms controlling the subcellular localization of PC1 and PC2 are poorly understood. Here, we investigated the involvement of the retromer complex, an ancient protein module initially discovered in yeast that regulates the retrieval, sorting, and retrograde transport of membrane receptors. Using yeast two-hybrid, biochemical, and cellular assays, we determined that PC2 binds two isoforms of the retromer-associated protein sorting nexin 3 (SNX3), including a novel isoform that binds PC2 in a direct manner. Knockdown of SNX3 or the core retromer protein VPS35 increased the surface expression of endogenous PC1 and PC2 in vitro and in vivo and increased Wnt-activated PC2-dependent whole-cell currents. These findings indicate that an SNX3-retromer complex regulates the surface expression and function of PC1 and PC2. Molecular targeting of proteins involved in the endosomal sorting of PC1 and PC2 could lead to new therapeutic approaches in ADPKD.
Collapse
Affiliation(s)
- Shuang Feng
- Kidney Genetics Group, Academic Nephrology Unit and the Bateson Centre, Department of Infection, Immunity and Cardiovascular Disease, University of Sheffield Medical School, Sheffield, United Kingdom
| | - Andrew J Streets
- Kidney Genetics Group, Academic Nephrology Unit and the Bateson Centre, Department of Infection, Immunity and Cardiovascular Disease, University of Sheffield Medical School, Sheffield, United Kingdom
| | - Vasyl Nesin
- Department of Cell Biology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma; and
| | - Uyen Tran
- Department of Cellular and Molecular Medicine, Lerner Research Institute, Cleveland Clinic Foundation, Cleveland, Ohio
| | - Hongguang Nie
- Department of Cell Biology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma; and
| | - Marta Onopiuk
- Department of Cell Biology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma; and
| | - Oliver Wessely
- Department of Cellular and Molecular Medicine, Lerner Research Institute, Cleveland Clinic Foundation, Cleveland, Ohio
| | - Leonidas Tsiokas
- Department of Cell Biology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma; and
| | - Albert C M Ong
- Kidney Genetics Group, Academic Nephrology Unit and the Bateson Centre, Department of Infection, Immunity and Cardiovascular Disease, University of Sheffield Medical School, Sheffield, United Kingdom;
| |
Collapse
|
16
|
Gamberi C, Hipfner DR, Trudel M, Lubell WD. Bicaudal C mutation causes myc and TOR pathway up-regulation and polycystic kidney disease-like phenotypes in Drosophila. PLoS Genet 2017; 13:e1006694. [PMID: 28406902 PMCID: PMC5390980 DOI: 10.1371/journal.pgen.1006694] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2016] [Accepted: 03/15/2017] [Indexed: 12/26/2022] Open
Abstract
Progressive cystic kidney degeneration underlies diverse renal diseases, including the most common cause of kidney failure, autosomal dominant Polycystic Kidney Disease (PKD). Genetic analyses of patients and animal models have identified several key drivers of this disease. The precise molecular and cellular changes underlying cystogenesis remain, however, elusive. Drosophila mutants lacking the translational regulator Bicaudal C (BicC, the fly ortholog of vertebrate BICC1 implicated in renal cystogenesis) exhibited progressive cystic degeneration of the renal tubules (so called “Malpighian” tubules) and reduced renal function. The BicC protein was shown to bind to Drosophila (d-) myc mRNA in tubules. Elevation of d-Myc protein levels was a cause of tubular degeneration in BicC mutants. Activation of the Target of Rapamycin (TOR) kinase pathway, another common feature of PKD, was found in BicC mutant flies. Rapamycin administration substantially reduced the cystic phenotype in flies. We present new mechanistic insight on BicC function and propose that Drosophila may serve as a genetically tractable model for dissecting the evolutionarily-conserved molecular mechanisms of renal cystogenesis. Polycystic kidney disease (PKD) is a degenerative, potentially lethal, genetic malady that affects 12.5 million people world-wide for which there is no cure. In the kidney, PKD causes the formation of prominent, fluid-filled cysts the growth of which damages progressively kidney function. Crucial to PKD development, mutations in the PKD1 and PKD2 genes cause renal cystic degeneration via factors and mechanisms that are only partially known. This manuscript reports novel insights into the molecular mechanisms of the evolutionarily conserved RNA binding protein BicC, which has been implicated in vertebrate cystic kidney diseases. The BicC mutants of the fruit fly Drosophila melanogaster recapitulate crucial characteristics of PKD. A clear link between BicC and PKD has begun to emerge, in part because both PKD1 patients and Pkd1 mice exhibit reduced BicC function. This first in kind Drosophila model of renal cystogenesis offers strong potential to decipher the complex mechanisms of the molecular and cellular changes causing renal cyst formation.
Collapse
Affiliation(s)
- Chiara Gamberi
- Department of Biology, Concordia University, Montréal, QC, Canada
- * E-mail:
| | - David R. Hipfner
- Institut de recherches cliniques de Montréal, 110 Pine Avenue West, Montréal, QC, Canada
- Département de médecine, Université de Montréal, Montréal, QC, Canada
| | - Marie Trudel
- Institut de recherches cliniques de Montréal, 110 Pine Avenue West, Montréal, QC, Canada
- Département de médecine, Université de Montréal, Montréal, QC, Canada
| | | |
Collapse
|
17
|
Manojlovic Z, Earwood R, Kato A, Perez D, Cabrera OA, Didier R, Megraw TL, Stefanovic B, Kato Y. La-related protein 6 controls ciliated cell differentiation. Cilia 2017; 6:4. [PMID: 28344782 PMCID: PMC5364628 DOI: 10.1186/s13630-017-0047-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2016] [Accepted: 02/16/2017] [Indexed: 01/07/2023] Open
Abstract
Background La-related protein 6 (LARP6) is an evolutionally conserved RNA-binding protein. Vertebrate LARP6 binds the 5′ stem-loop found in mRNAs encoding type I collagen to regulate their translation, but other target mRNAs and additional functions for LARP6 are unknown. The aim of this study was to elucidate an additional function of LARP6 and to evaluate the importance of its function during development. Methods To uncover the role of LARP6 in development, we utilized Morpholino Oligos to deplete LARP6 protein in Xenopus embryos. Then, embryonic phenotypes and ciliary structures of LAPR6 morphants were examined. To identify the molecular mechanism underlying ciliogenesis regulated by LARP6, we tested the expression level of cilia-related genes, which play important roles in ciliogenesis, by RT-PCR or whole mount in situ hybridization (WISH). Results We knocked down LARP6 in Xenopus embryos and found neural tube closure defects. LARP6 mutant, which compromises the collagen synthesis, could rescue these defects. Neural tube closure defects are coincident with lack of cilia, antenna-like cellular organelles with motility- or sensory-related functions, in the neural tube. The absence of cilia at the epidermis was also observed in LARP6 morphants, and this defect was due to the absence of basal bodies which are formed from centrioles and required for ciliary assembly. In the process of multi-ciliated cell (MCC) differentiation, mcidas, which activates the transcription of genes required for centriole formation during ciliogenesis, could partially restore MCCs in LARP6 morphants. In addition, LARP6 likely controls the expression of mcidas in a Notch-independent manner. Conclusions La-related protein 6 is involved in ciliated cell differentiation during development by controlling the expression of cilia-related genes including mcidas. This LARP6 function involves a mechanism that is distinct from its established role in binding to collagen mRNAs and regulating their translation. Electronic supplementary material The online version of this article (doi:10.1186/s13630-017-0047-7) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Zarko Manojlovic
- Department of Biomedical Sciences, Florida State University College of Medicine, 1115W. Call Street, Tallahassee, FL 32306-4300 USA.,Department of Translational Genomics, Keck School of Medicine of University of Southern California, Los Angeles, CA 90089-9601 USA
| | - Ryan Earwood
- Department of Biomedical Sciences, Florida State University College of Medicine, 1115W. Call Street, Tallahassee, FL 32306-4300 USA
| | - Akiko Kato
- Department of Biomedical Sciences, Florida State University College of Medicine, 1115W. Call Street, Tallahassee, FL 32306-4300 USA
| | - Diana Perez
- Department of Biomedical Sciences, Florida State University College of Medicine, 1115W. Call Street, Tallahassee, FL 32306-4300 USA
| | - Oscar A Cabrera
- Department of Biomedical Sciences, Florida State University College of Medicine, 1115W. Call Street, Tallahassee, FL 32306-4300 USA
| | - Ruth Didier
- Department of Biomedical Sciences, Florida State University College of Medicine, 1115W. Call Street, Tallahassee, FL 32306-4300 USA
| | - Timothy L Megraw
- Department of Biomedical Sciences, Florida State University College of Medicine, 1115W. Call Street, Tallahassee, FL 32306-4300 USA
| | - Branko Stefanovic
- Department of Biomedical Sciences, Florida State University College of Medicine, 1115W. Call Street, Tallahassee, FL 32306-4300 USA
| | - Yoichi Kato
- Department of Biomedical Sciences, Florida State University College of Medicine, 1115W. Call Street, Tallahassee, FL 32306-4300 USA
| |
Collapse
|
18
|
Kim S, Nie H, Nesin V, Tran U, Outeda P, Bai CX, Keeling J, Maskey D, Watnick T, Wessely O, Tsiokas L. The polycystin complex mediates Wnt/Ca(2+) signalling. Nat Cell Biol 2016; 18:752-764. [PMID: 27214281 PMCID: PMC4925210 DOI: 10.1038/ncb3363] [Citation(s) in RCA: 120] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2015] [Accepted: 04/22/2016] [Indexed: 01/22/2023]
Abstract
WNT ligands induce Ca2+ signaling on target cells. PKD1 (Polycystin 1) is considered an orphan, atypical G protein coupled receptor complexed with TRPP2 (Polycystin 2 or PKD2), a Ca2+-permeable ion channel. Inactivating mutations in their genes cause autosomal dominant polycystic kidney disease (ADPKD), one of the most common genetic diseases. Here, we show that WNTs bind to the extracellular domain of PKD1 and induce whole cell currents and Ca2+ influx dependent on TRPP2. Pathogenic PKD1 or PKD2 mutations that abrogate complex formation, compromise cell surface expression of PKD1, or reduce TRPP2 channel activity suppress activation by WNTs. Pkd2−/− fibroblasts lack WNT-induced Ca2+ currents and are unable to polarize during directed cell migration. In Xenopus embryos, PKD1, Dishevelled 2 (DVL2), and WNT9A act within the same pathway to preserve normal tubulogenesis. These data define PKD1 as a WNT (co)receptor and implicate defective WNT/Ca2+ signaling as one of the causes of ADPKD.
Collapse
Affiliation(s)
- Seokho Kim
- Department of Cell Biology, University of Oklahoma Health Sciences Center, 975 NE 10th Street, Oklahoma City, OK 73104, USA
| | - Hongguang Nie
- Department of Cell Biology, University of Oklahoma Health Sciences Center, 975 NE 10th Street, Oklahoma City, OK 73104, USA.,Institute of Metabolic Disease Research and Drug Development, China Medical University, Liaoning Shenyang, 110001 China (H.N)
| | - Vasyl Nesin
- Department of Cell Biology, University of Oklahoma Health Sciences Center, 975 NE 10th Street, Oklahoma City, OK 73104, USA
| | - Uyen Tran
- Department of Cellular and Molecular Medicine, Cleveland Clinic, 9500 Euclid Avenue/NC10, Cleveland, OH 44195, USA
| | - Patricia Outeda
- Division of Nephrology, Baltimore PKD Research and Clinical Core Center, University of Maryland School of Medicine, 655 West Baltimore Street, Baltimore, MD 21201, USA
| | - Chang-Xi Bai
- Department of Cell Biology, University of Oklahoma Health Sciences Center, 975 NE 10th Street, Oklahoma City, OK 73104, USA.,Department of Advanced Research on Mongolian Medicine, Research Institute for Mongolian Medicine, Inner Mongolia Medical University, Hohhot 010110, Inner Mongolia, China (CB)
| | - Jacob Keeling
- Department of Cell Biology, University of Oklahoma Health Sciences Center, 975 NE 10th Street, Oklahoma City, OK 73104, USA
| | - Dipak Maskey
- Department of Cell Biology, University of Oklahoma Health Sciences Center, 975 NE 10th Street, Oklahoma City, OK 73104, USA
| | - Terry Watnick
- Division of Nephrology, Baltimore PKD Research and Clinical Core Center, University of Maryland School of Medicine, 655 West Baltimore Street, Baltimore, MD 21201, USA
| | - Oliver Wessely
- Department of Cellular and Molecular Medicine, Cleveland Clinic, 9500 Euclid Avenue/NC10, Cleveland, OH 44195, USA
| | - Leonidas Tsiokas
- Department of Cell Biology, University of Oklahoma Health Sciences Center, 975 NE 10th Street, Oklahoma City, OK 73104, USA
| |
Collapse
|
19
|
Park S, Blaser S, Marchal MA, Houston DW, Sheets MD. A gradient of maternal Bicaudal-C controls vertebrate embryogenesis via translational repression of mRNAs encoding cell fate regulators. Development 2016; 143:864-71. [PMID: 26811381 PMCID: PMC4813341 DOI: 10.1242/dev.131359] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2015] [Accepted: 01/16/2016] [Indexed: 12/16/2022]
Abstract
Vertebrate Bicaudal-C (Bicc1) has important biological roles in the formation and homeostasis of multiple organs, but direct experiments to address the role of maternal Bicc1 in early vertebrate embryogenesis have not been reported. Here, we use antisense phosphorothioate-modified oligonucleotides and the host-transfer technique to eliminate specifically maternal stores of both bicc1 mRNA and Bicc1 protein from Xenopus laevis eggs. Fertilization of these Bicc1-depleted eggs produced embryos with an excess of dorsal-anterior structures and overexpressed organizer-specific genes, indicating that maternal Bicc1 is crucial for normal embryonic patterning of the vertebrate embryo. Bicc1 is an RNA-binding protein with robust translational repression function. Here, we show that the maternal mRNA encoding the cell-fate regulatory protein Wnt11b is a direct target of Bicc1-mediated repression. It is well established that the Wnt signaling pathway is crucial to vertebrate embryogenesis. Thus, the work presented here links the molecular function of Bicc1 in mRNA target-specific translation repression to its biological role in the maternally controlled stages of vertebrate embryogenesis.
Collapse
Affiliation(s)
- Sookhee Park
- Department of Biomolecular Chemistry, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Susanne Blaser
- Department of Biomolecular Chemistry, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI 53706, USA
| | | | | | - Michael D Sheets
- Department of Biomolecular Chemistry, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI 53706, USA
| |
Collapse
|
20
|
Xu Y, Streets AJ, Hounslow AM, Tran U, Jean-Alphonse F, Needham AJ, Vilardaga JP, Wessely O, Williamson MP, Ong ACM. The Polycystin-1, Lipoxygenase, and α-Toxin Domain Regulates Polycystin-1 Trafficking. J Am Soc Nephrol 2015; 27:1159-73. [PMID: 26311459 DOI: 10.1681/asn.2014111074] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2014] [Accepted: 07/21/2015] [Indexed: 12/24/2022] Open
Abstract
Mutations in polycystin-1 (PC1) give rise to autosomal dominant polycystic kidney disease, an important and common cause of kidney failure. Despite its medical importance, the function of PC1 remains poorly understood. Here, we investigated the role of the intracellular polycystin-1, lipoxygenase, and α-toxin (PLAT) signature domain of PC1 using nuclear magnetic resonance, biochemical, cellular, and in vivo functional approaches. We found that the PLAT domain targets PC1 to the plasma membrane in polarized epithelial cells by a mechanism involving the selective binding of the PLAT domain to phosphatidylserine and L-α-phosphatidylinositol-4-phosphate (PI4P) enriched in the plasma membrane. This process is regulated by protein kinase A phosphorylation of the PLAT domain, which reduces PI4P binding and recruits β-arrestins and the clathrin adaptor AP2 to trigger PC1 internalization. Our results reveal a physiological role for the PC1-PLAT domain in renal epithelial cells and suggest that phosphorylation-dependent internalization of PC1 is closely linked to its function in renal development and homeostasis.
Collapse
Affiliation(s)
- Yaoxian Xu
- Kidney Genetics Group, Academic Nephrology Unit, University of Sheffield Medical School, Sheffield, United Kingdom; Department of Molecular Biology and Biotechnology, University of Sheffield, Sheffield, United Kingdom
| | - Andrew J Streets
- Kidney Genetics Group, Academic Nephrology Unit, University of Sheffield Medical School, Sheffield, United Kingdom
| | - Andrea M Hounslow
- Department of Molecular Biology and Biotechnology, University of Sheffield, Sheffield, United Kingdom
| | - Uyen Tran
- Department of Cellular and Molecular Medicine, Cleveland Clinic Foundation, Cleveland, Ohio; and
| | - Frederic Jean-Alphonse
- Laboratory of GPCR Biology, Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Andrew J Needham
- Kidney Genetics Group, Academic Nephrology Unit, University of Sheffield Medical School, Sheffield, United Kingdom
| | - Jean-Pierre Vilardaga
- Laboratory of GPCR Biology, Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Oliver Wessely
- Department of Cellular and Molecular Medicine, Cleveland Clinic Foundation, Cleveland, Ohio; and
| | - Michael P Williamson
- Department of Molecular Biology and Biotechnology, University of Sheffield, Sheffield, United Kingdom
| | - Albert C M Ong
- Kidney Genetics Group, Academic Nephrology Unit, University of Sheffield Medical School, Sheffield, United Kingdom;
| |
Collapse
|
21
|
Abstract
Loss of the RNA-binding protein Bicaudal-C (Bicc1) provokes renal and pancreatic cysts as well as ectopic Wnt/β-catenin signaling during visceral left-right patterning. Renal cysts are linked to defective silencing of Bicc1 target mRNAs, including adenylate cyclase 6 (AC6). RNA binding of Bicc1 is mediated by N-terminal KH domains, whereas a C-terminal sterile alpha motif (SAM) self-polymerizes in vitro and localizes Bicc1 in cytoplasmic foci in vivo. To assess a role for multimerization in silencing, we conducted structure modeling and then mutated the SAM domain residues which in this model were predicted to polymerize Bicc1 in a left-handed helix. We show that a SAM-SAM interface concentrates Bicc1 in cytoplasmic clusters to specifically localize and silence bound mRNA. In addition, defective polymerization decreases Bicc1 stability and thus indirectly attenuates inhibition of Dishevelled 2 in the Wnt/β-catenin pathway. Importantly, aberrant C-terminal extension of the SAM domain in bpk mutant Bicc1 phenocopied these defects. We conclude that polymerization is a novel disease-relevant mechanism both to stabilize Bicc1 and to present associated mRNAs in specific silencing platforms.
Collapse
|
22
|
Yang H, Lee YM, Lee JH, Noh JK, Kim HC, Park CJ, Park JW, Hwang IJ, Kim SY. Expression of Perforin Gene for Early Development of Nephrons in Olive Flounder (Paralichthys olivaceus). Dev Reprod 2015; 17:321-7. [PMID: 25949147 PMCID: PMC4382958 DOI: 10.12717/dr.2013.17.4.321] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2013] [Revised: 12/02/2013] [Accepted: 12/10/2013] [Indexed: 11/17/2022]
Abstract
The innate immune system is the only defense weapon that invertebrates have, and it is the fundamental defense mechanism for fish. The innate immune response is important in newly hatched flounders because it is closely involved in the initial feeding phase, which is why it is essential for survival during the juvenile period. The expression analysis of genes involved in the innate immune response in the olive flounder (Paralichthys olivaceus) in the days after hatching is incomplete. Therefore, we have begun to examine the expression patterns of genes specifically induced during the development of the innate immune system in newly hatched flounders. Microscopic observation showed that pronephron formation corresponded with the expression of perforin-encoding gene. These results suggest that perforin plays a vital role in the innate immunity of the kidney during developmental stages. Perforin expression was strong at the start of the development of the innate immune response, and continued throughout all the development stages. Our findings have important implications with respect to perforin’s biological role and the evolution of the first defense mechanisms in olive flounder. Further studies are required to elucidate the perforin-mediated innate immunity response and to decipher the functional role of perforin in developmental stages.
Collapse
Affiliation(s)
- Hyun Yang
- Genetics and Breeding Research Center, NFRDI, Geoje 656-842, Republic of Korea
| | - Young Mee Lee
- Genetics and Breeding Research Center, NFRDI, Geoje 656-842, Republic of Korea
| | - Jeong-Ho Lee
- Genetics and Breeding Research Center, NFRDI, Geoje 656-842, Republic of Korea
| | - Jae Koo Noh
- Genetics and Breeding Research Center, NFRDI, Geoje 656-842, Republic of Korea
| | - Hyun Chul Kim
- Genetics and Breeding Research Center, NFRDI, Geoje 656-842, Republic of Korea
| | - Choul-Ji Park
- Genetics and Breeding Research Center, NFRDI, Geoje 656-842, Republic of Korea
| | - Jong-Won Park
- Genetics and Breeding Research Center, NFRDI, Geoje 656-842, Republic of Korea
| | - In Joon Hwang
- Genetics and Breeding Research Center, NFRDI, Geoje 656-842, Republic of Korea
| | - Sung Yeon Kim
- Genetics and Breeding Research Center, NFRDI, Geoje 656-842, Republic of Korea
| |
Collapse
|
23
|
Schweickert A, Feistel K. The Xenopus Embryo: An Ideal Model System to Study Human Ciliopathies. CURRENT PATHOBIOLOGY REPORTS 2015. [DOI: 10.1007/s40139-015-0074-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
|
24
|
Dichmann DS, Walentek P, Harland RM. The alternative splicing regulator Tra2b is required for somitogenesis and regulates splicing of an inhibitory Wnt11b isoform. Cell Rep 2015; 10:527-36. [PMID: 25620705 DOI: 10.1016/j.celrep.2014.12.046] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2014] [Revised: 11/25/2014] [Accepted: 12/18/2014] [Indexed: 11/18/2022] Open
Abstract
Alternative splicing is pervasive in vertebrates, yet little is known about most isoforms or their regulation. transformer-2b (tra2b) encodes a splicing regulator whose endogenous function is poorly understood. Tra2b knockdown in Xenopus results in embryos with multiple defects, including defective somitogenesis. Using RNA sequencing, we identify 142 splice changes (mostly intron retention and exon skipping), 89% of which are not in current annotations. A previously undescribed isoform of wnt11b retains the last intron, resulting in a truncated ligand (Wnt11b-short). We show that this isoform acts as a dominant-negative ligand in cardiac gene induction and pronephric tubule formation. To determine the contribution of Wnt11b-short to the tra2b phenotype, we induce retention of intron 4 in wnt11b, which recapitulates the failure to form somites but not other tra2b morphant defects. This alternative splicing of a Wnt ligand adds intricacy to a complex signaling pathway and highlights intron retention as a regulatory mechanism.
Collapse
Affiliation(s)
- Darwin S Dichmann
- Department of Molecular & Cell Biology, 142 Life Sciences Addition #3200, University of California, Berkeley, Berkeley, CA 94720-3200, USA.
| | - Peter Walentek
- Department of Molecular & Cell Biology, 142 Life Sciences Addition #3200, University of California, Berkeley, Berkeley, CA 94720-3200, USA
| | - Richard M Harland
- Department of Molecular & Cell Biology, 142 Life Sciences Addition #3200, University of California, Berkeley, Berkeley, CA 94720-3200, USA.
| |
Collapse
|
25
|
Shi W, Xu G, Wang C, Sperber SM, Chen Y, Zhou Q, Deng Y, Zhao H. Heat shock 70-kDa protein 5 (Hspa5) is essential for pronephros formation by mediating retinoic acid signaling. J Biol Chem 2015; 290:577-89. [PMID: 25398881 PMCID: PMC4281759 DOI: 10.1074/jbc.m114.591628] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2014] [Revised: 11/09/2014] [Indexed: 12/17/2022] Open
Abstract
Heat shock 70-kDa protein 5 (Hspa5), also known as binding immunoglobulin protein (Bip) or glucose-regulated protein 78 (Grp78), belongs to the heat shock protein 70 kDa family. As a multifunctional protein, it participates in protein folding and calcium homeostasis and serves as an essential regulator of the endoplasmic reticulum (ER) stress response. It has also been implicated in signal transduction by acting as a receptor or co-receptor residing at the plasma membrane. Its function during embryonic development, however, remains largely elusive. In this study, we used morpholino antisense oligonucleotides (MOs) to knock down Hspa5 activity in Xenopus embryos. In Hspa5 morphants, pronephros formation was strongly inhibited with the reduction of pronephric marker genes Lim homeobox protein 1 (lhx1), pax2, and β1 subunit of Na/K-ATPase (atp1b1). Pronephros tissue was induced in vitro by treating animal caps with all-trans-retinoic acid and activin. Depletion of Hspa5 in animal caps, however, blocked the induction of pronephros as well as reduced the expression of retinoic acid (RA)-responsive genes, suggesting that knockdown of Hspa5 attenuated RA signaling. Knockdown of Hspa5 in animal caps resulted in decreased expression of lhx1, a transcription factor directly regulated by RA signaling and essential for pronephros specification. Co-injection of Hspa5MO with lhx1 mRNA partially rescued the phenotype induced by Hspa5MO. These results suggest that the RA-Lhx1 signaling cascade is involved in Hspa5MO-induced pronephros malformation. This study shows that Hspa5, a key regulator of the unfolded protein response, plays an essential role in pronephros formation, which is mediated in part through RA signaling during early embryonic development.
Collapse
Affiliation(s)
- Weili Shi
- 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 Special Administrative Region (SAR), China
| | - Gang Xu
- School of Chinese Medicine, Hong Kong Baptist University, 7 Baptist University Road, Kowloon Tong, Hong Kong SAR, China
| | - Chengdong Wang
- 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 Special Administrative Region (SAR), China, Shenzhen Research Institute, The Chinese University of Hong Kong, Shenzhen 518057, China
| | - Steven M Sperber
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, New York 10029-6574
| | - Yonglong Chen
- Key Laboratory of Regenerative Biology, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou 510530, China, and
| | - Qin Zhou
- Division of Molecular Nephrology and Creative Training Center for Undergraduates, Ministry of Education Key Laboratory of Laboratory Medicine Diagnostics, College of Laboratory Medicine, Chongqing Medical University, Chongqing 400016, China
| | - Yi Deng
- Department of Biology, South University of Science and Technology of China, Shenzhen 518055, China,
| | - Hui Zhao
- 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 Special Administrative Region (SAR), China, Shenzhen Research Institute, The Chinese University of Hong Kong, Shenzhen 518057, China,
| |
Collapse
|
26
|
Cerqueira DM, Tran U, Romaker D, Abreu JG, Wessely O. Sterol carrier protein 2 regulates proximal tubule size in the Xenopus pronephric kidney by modulating lipid rafts. Dev Biol 2014; 394:54-64. [PMID: 25127994 DOI: 10.1016/j.ydbio.2014.07.025] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2013] [Revised: 05/29/2014] [Accepted: 07/30/2014] [Indexed: 11/29/2022]
Abstract
The kidney is a homeostatic organ required for waste excretion and reabsorption of water, salts and other macromolecules. To this end, a complex series of developmental steps ensures the formation of a correctly patterned and properly proportioned organ. While previous studies have mainly focused on the individual signaling pathways, the formation of higher order receptor complexes in lipid rafts is an equally important aspect. These membrane platforms are characterized by differences in local lipid and protein compositions. Indeed, the cells in the Xenopus pronephric kidney were positive for the lipid raft markers ganglioside GM1 and Caveolin-1. To specifically interfere with lipid raft function in vivo, we focused on the Sterol Carrier Protein 2 (scp2), a multifunctional protein that is an important player in remodeling lipid raft composition. In Xenopus, scp2 mRNA was strongly expressed in differentiated epithelial structures of the pronephric kidney. Knockdown of scp2 did not interfere with the patterning of the kidney along its proximo-distal axis, but dramatically decreased the size of the kidney, in particular the proximal tubules. This phenotype was accompanied by a reduction of lipid rafts, but was independent of the peroxisomal or transcriptional activities of scp2. Finally, disrupting lipid micro-domains by inhibiting cholesterol synthesis using Mevinolin phenocopied the defects seen in scp2 morphants. Together these data underscore the importance for localized signaling platforms in the proper formation of the Xenopus kidney.
Collapse
Affiliation(s)
- Débora M Cerqueira
- Cleveland Clinic Foundation, Lerner Research Institute, Department Cellular and Molecular Medicine, 9500 Euclid Avenue/NC10 Cleveland, OH 44195, USA; Universidade Federal do Rio de Janeiro, Instituto de Ciências Biomédicas-CCS, Av. Carlos Chagas Filho, 373 bloco F2 sala 15, Rio de Janeiro 21949-590, Brazil
| | - Uyen Tran
- Cleveland Clinic Foundation, Lerner Research Institute, Department Cellular and Molecular Medicine, 9500 Euclid Avenue/NC10 Cleveland, OH 44195, USA
| | - Daniel Romaker
- Cleveland Clinic Foundation, Lerner Research Institute, Department Cellular and Molecular Medicine, 9500 Euclid Avenue/NC10 Cleveland, OH 44195, USA
| | - José G Abreu
- Universidade Federal do Rio de Janeiro, Instituto de Ciências Biomédicas-CCS, Av. Carlos Chagas Filho, 373 bloco F2 sala 15, Rio de Janeiro 21949-590, Brazil
| | - Oliver Wessely
- Cleveland Clinic Foundation, Lerner Research Institute, Department Cellular and Molecular Medicine, 9500 Euclid Avenue/NC10 Cleveland, OH 44195, USA.
| |
Collapse
|
27
|
MicroRNAs are critical regulators of tuberous sclerosis complex and mTORC1 activity in the size control of the Xenopus kidney. Proc Natl Acad Sci U S A 2014; 111:6335-40. [PMID: 24733901 DOI: 10.1073/pnas.1320577111] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
MicroRNAs (miRNAs) are major posttranscriptional regulators of a wide variety of biological processes. However, redundancy among most miRNAs has made it difficult to identify their in vivo functions. We previously demonstrated that global inhibition of miRNA biogenesis in Xenopus resulted in a dramatically smaller pronephric kidney. This suggested that microRNAs play a pivotal role in organ size control. Here we now provide a detailed mechanistic explanation for this phenotype. We identified that the activation of the mechanistic target of rapamycin complex 1 (mTORC1) by Insulin and insulin-like growth factor (Igf) 2 is an important regulator in kidney growth, which in turn is modulated by microRNAs. Molecular analyses demonstrate that microRNAs set a threshold for mTORC1 signaling by down-regulating one of its core negative regulators, tuberous sclerosis 1 (Tsc1). Most importantly, this rheostat can be reprogrammed experimentally. Whereas knockdown of miRNAs causes growth arrest, concomitant knockdown of Tsc1 restores mTORC1 activity and proximal tubular size. Together, these data establish a previously unidentified in vivo paradigm for the importance of posttranscriptional regulation in organ size control.
Collapse
|
28
|
Schmitt SM, Gull M, Brändli AW. Engineering Xenopus embryos for phenotypic drug discovery screening. Adv Drug Deliv Rev 2014; 69-70:225-46. [PMID: 24576445 DOI: 10.1016/j.addr.2014.02.004] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2014] [Revised: 02/13/2014] [Accepted: 02/14/2014] [Indexed: 02/08/2023]
Abstract
Many rare human inherited diseases remain untreatable despite the fact that the disease causing genes are known and adequate mouse disease models have been developed. In vivo phenotypic drug screening relies on isolating drug candidates by their ability to produce a desired therapeutic phenotype in whole organisms. Embryos of zebrafish and Xenopus frogs are abundant, small and free-living. They can be easily arrayed in multi-well dishes and treated with small organic molecules. With the development of novel genome modification tools, such a zinc-finger nucleases (ZFNs), transcription activator-like effector nucleases (TALENs), and CRISPR/Cas, it is now possible to efficiently engineer non-mammalian models of inherited human diseases. Here, we will review the rapid progress made in adapting these novel genome editing tools to Xenopus. The advantages of Xenopus embryos as in vivo models to study human inherited diseases will be presented and their utility for drug discovery screening will be discussed. Being a tetrapod, Xenopus complements zebrafish as an indispensable non-mammalian animal model for the study of human disease pathologies and the discovery of novel therapeutics for inherited diseases.
Collapse
|
29
|
Hoff S, Halbritter J, Epting D, Frank V, Nguyen TMT, van Reeuwijk J, Boehlke C, Schell C, Yasunaga T, Helmstädter M, Mergen M, Filhol E, Boldt K, Horn N, Ueffing M, Otto EA, Eisenberger T, Elting MW, van Wijk JAE, Bockenhauer D, Sebire NJ, Rittig S, Vyberg M, Ring T, Pohl M, Pape L, Neuhaus TJ, Elshakhs NAS, Koon SJ, Harris PC, Grahammer F, Huber TB, Kuehn EW, Kramer-Zucker A, Bolz HJ, Roepman R, Saunier S, Walz G, Hildebrandt F, Bergmann C, Lienkamp SS. ANKS6 is a central component of a nephronophthisis module linking NEK8 to INVS and NPHP3. Nat Genet 2013; 45:951-6. [PMID: 23793029 PMCID: PMC3786259 DOI: 10.1038/ng.2681] [Citation(s) in RCA: 151] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2013] [Accepted: 06/03/2013] [Indexed: 11/09/2022]
Abstract
Nephronophthisis (NPH) is an autosomal recessive cystic kidney disease that leads to renal failure in childhood or adolescence. Most NPHP gene products form molecular networks. We have identified ANKS6 as a new NPHP family member that connects NEK8 (NPHP9) to INVERSIN (INVS, NPHP2) and NPHP3 to form a distinct NPHP module. ANKS6 localizes to the proximal cilium and knockdown experiments in zebrafish and Xenopus confirmed a role in renal development. Genetic screening identified six families with ANKS6 mutations and NPH, including severe cardiovascular abnormalities, liver fibrosis and situs inversus. The oxygen sensor HIF1AN (FIH) hydroxylates ANKS6 and INVS, while knockdown of Hif1an in Xenopus resembled the loss of other NPHP proteins. HIF1AN altered the composition of the ANKS6/INVS/NPHP3 module. Network analyses, uncovering additional putative NPHP-associated genes, placed ANKS6 at the center of the NPHP module, explaining the overlapping disease manifestation caused by mutations of either ANKS6, NEK8, INVS or NPHP3.
Collapse
Affiliation(s)
- Sylvia Hoff
- Department of Medicine, Renal Division, University of Freiburg Medical Center, Freiburg, Germany
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
30
|
Streets AJ, Wessely O, Peters DJM, Ong ACM. Hyperphosphorylation of polycystin-2 at a critical residue in disease reveals an essential role for polycystin-1-regulated dephosphorylation. Hum Mol Genet 2013; 22:1924-39. [PMID: 23390129 DOI: 10.1093/hmg/ddt031] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Mutations in PKD1 (85%) or PKD2 (15%) account for almost all cases of autosomal dominant polycystic kidney disease (ADPKD). The ADPKD proteins, termed as polycystin-1 (PC1) and polycystin-2 (PC2), interact via their C-termini to form a receptor-ion channel complex whose function and regulation are not fully understood. Here, we report the first phosphorylated residue (Ser(829)) in PC2, whose dephosphorylation is mediated by PC1 binding through the recruitment of protein phosphatase-1 alpha (PP1α). Using a new phosphospecific antibody (pPC2) to this site, we demonstrate that Ser(829) is phosphorylated by Protein kinase A (PKA) but remains constitutively phosphorylated in cells and tissues lacking PC1. cAMP increased pSer(829) basolateral localization in MDCK cells in a time dependent manner and was essential for pronephric development in Xenopus embryos. When constitutively expressed, a complex phenotype associated with enhanced ATP-dependent ER Ca(2+) release and loss of growth suppression was observed in cycling cells. These results reveal a reciprocal functional link between PC1 and PC2 which is critically dependent on their interaction. Unopposed cAMP stimulated hyperphosphorylation of PC2 in the absence of functional PC1 could contribute to cyst initiation in PKD1 patients and represents a new molecular paradigm in understanding ADPKD pathogenesis.
Collapse
Affiliation(s)
- Andrew J Streets
- Kidney Genetics Group, Academic Nephrology Unit, Henry Wellcome Laboratories for Medical Research,University of Sheffield Medical School, Sheffield, UK
| | | | | | | |
Collapse
|
31
|
Zhang B, Romaker D, Ferrell N, Wessely O. Regulation of G-protein signaling via Gnas is required to regulate proximal tubular growth in the Xenopus pronephros. Dev Biol 2013; 376:31-42. [PMID: 23352791 DOI: 10.1016/j.ydbio.2013.01.017] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2012] [Revised: 01/10/2013] [Accepted: 01/14/2013] [Indexed: 11/17/2022]
Abstract
In the kidney, proximal tubules are very important for the reabsorption of water, ions and organic solutes from the primary urine. They are composed of highly specialized epithelial cells that are characterized by an elaborate apical brush border to increase transport efficiency. Using the pronephric kidney of Xenopus laevis we discovered that the G-protein modulator cholera toxin resulted in a dramatic reduction of the proximal tubular size. This phenotype was accompanied by changes in the cytoarchitecture characterized by ectopic expression of the distal tubular marker 4A6 and an impairment of yolk platelet degradation. In addition, cholera toxin caused edema formation. However, this phenotype was not due to kidney defects, but rather due to impaired vasculature development. Based on experiments with antisense morpholino oligomers as well as pharmacological agonists and antagonists, we could show that the complex phenotype of cholera toxin in the pronephric kidney was caused by the hyperactivation of a single G-protein alpha subunit, Gnas. This-in turn-caused elevated cAMP levels, triggered a Rapgef4-dependent signaling cassette and perturbed exo- and endocytosis. This perturbation of the secretory pathway by Ctx was not only observed in Xenopus embryos. Also, in a human proximal tubular cell line, cholera toxin or a Rapgef4-specific agonist increased uptake and decreased secretion of FITC-labeled Albumin. Based on these data we propose that the Gnas/cAMP/Rapgef4 pathway regulates the signals inducing the proliferation of proximal tubules to acquire their final organ size.
Collapse
Affiliation(s)
- Bo Zhang
- Cleveland Clinic Foundation, Lerner Research Institute, Department of Cellular and Molecular Medicine, 9500 Euclid Avenue/NC10, Cleveland, OH 44195, USA
| | | | | | | |
Collapse
|
32
|
Tréguer K, Faucheux C, Veschambre P, Fédou S, Thézé N, Thiébaud P. Comparative functional analysis of ZFP36 genes during Xenopus development. PLoS One 2013; 8:e54550. [PMID: 23342169 PMCID: PMC3546996 DOI: 10.1371/journal.pone.0054550] [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: 07/22/2012] [Accepted: 12/14/2012] [Indexed: 01/12/2023] Open
Abstract
ZFP36 constitutes a small family of RNA binding proteins (formerly known as the TIS11 family) that target mRNA and promote their degradation. In mammals, ZFP36 proteins are encoded by four genes and, although they show similar activities in a cellular RNA destabilization assay, there is still a limited knowledge of their mRNA targets and it is not known whether or not they have redundant functions. In the present work, we have used the Xenopus embryo, a model system allowing gain- and loss-of-function studies, to investigate, whether individual ZFP36 proteins had distinct or redundant functions. We show that overexpression of individual amphibian zfp36 proteins leads to embryos having the same defects, with alteration in somites segmentation and pronephros formation. In these embryos, members of the Notch signalling pathway such as hairy2a or esr5 mRNA are down-regulated, suggesting common targets for the different proteins. We also show that mouse Zfp36 protein overexpression gives the same phenotype, indicating an evolutionary conserved property among ZFP36 vertebrate proteins. Morpholino oligonucleotide-induced loss-of-function leads to defects in pronephros formation, reduction in tubule size and duct coiling alterations for both zfp36 and zfp36l1, indicating no functional redundancy between these two genes. Given the conservation in gene structure and function between the amphibian and mammalian proteins and the conserved mechanisms for pronephros development, our study highlights a potential and hitherto unreported role of ZFP36 gene in kidney morphogenesis.
Collapse
|
33
|
Wu J, Campbell ZT, Menichelli E, Wickens M, Williamson JR. A protein.protein interaction platform involved in recruitment of GLD-3 to the FBF.fem-3 mRNA complex. J Mol Biol 2012; 425:738-54. [PMID: 23159559 DOI: 10.1016/j.jmb.2012.11.013] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2012] [Revised: 11/01/2012] [Accepted: 11/07/2012] [Indexed: 02/03/2023]
Abstract
The Pumilio and FBF (PUF) family of RNA-binding proteins interacts with protein partners to post-transcriptionally regulate mRNAs in eukaryotes. The interaction between PUF family member fem-3 binding factor (FBF) and germline development defective-3 (GLD-3) protein promotes spermatogenesis in Caenorhabditis elegans by increasing expression of the fem-3 mRNA. Defined here in these studies is the molecular basis for this critical interaction. A 10-amino-acid region within GLD-3 is required for FBF binding, while a 7-amino-acid loop in FBF between PUF repeats 7 and 8 is necessary for GLD-3 binding. These short sequences are conserved, as other FBF-binding proteins bear sequences similar to those in GLD-3 and other C. elegans PUF proteins contain sequences similar to those in FBF. The FBF-binding region of GLD-3 forms a ternary complex with FBF on the point mutation element (PME) in the fem-3 3' untranslated region, and formation of this GLD-3⋅FBF complex does not impact the RNA-binding activity of FBF. These data raise the possibility of alternative models involving the formation of a GLD-3⋅FBF⋅RNA complex in the regulation of germline mRNAs.
Collapse
Affiliation(s)
- Joann Wu
- Department of Molecular Biology, Department of Chemistry, The Skaggs Institute for Chemical Biology, The Scripps Research Institute, La Jolla, CA 92037, USA
| | | | | | | | | |
Collapse
|
34
|
Thumberger T, Hagenlocher C, Tisler M, Beyer T, Tietze N, Schweickert A, Feistel K, Blum M. Ciliary and non-ciliary expression and function of PACRG during vertebrate development. Cilia 2012; 1:13. [PMID: 23351225 PMCID: PMC3555705 DOI: 10.1186/2046-2530-1-13] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2012] [Accepted: 05/30/2012] [Indexed: 01/07/2023] Open
Abstract
Background Park2-co-regulated gene (PACRG) is evolutionarily highly conserved from green algae to mammals. In Chlamydomonas and trypanosomes, the PACRG protein associates with flagella. Loss of PACRG results in shortened or absent flagella. In mouse the PACRG protein is required for spermatogenesis. The purpose of the present study was to analyze (1) the expression patterns of PACRG during vertebrate embryogenesis, and (2) whether the PACRG protein was required for left-right (LR) axis specification through cilia-driven leftward flow in Xenopus laevis. Methods PACRG cDNAs were cloned and expression was analyzed during early embryonic development of Xenopus, mouse, rabbit and zebrafish. Antisense morpholino oligonucleotide (MO) mediated gene knockdown was applied in Xenopus to investigate LR development at the level of tissue morphology, leftward flow and asymmetric marker gene expression, using timelapse videography, scanning electron microscopy (SEM) and whole-mount in situ hybridization. Results were statistically evaluated using Wilcoxon paired and χ2 tests. Results PACRG mRNA expression was found in cells and tissues harboring cilia throughout the vertebrates. Highly localized expression was also detected in the brain. During early development, PACRG was specifically localized to epithelia where leftward flow arises, that is, the gastrocoel roof plate (GRP) in Xenopus, the posterior notochord (PNC) in mammals and Kupffer’s vesicle (KV) in zebrafish. Besides its association with ciliary axonemes, subcellular localization of PACRG protein was found around the nucleus and in a spotty pattern in the cytoplasm. A green fluorescent protein (GFP) fusion construct preferentially labeled cilia, rendering PACRG a versatile marker for live imaging. Loss-of-function in the frog resulted dose dependently in LR, neural tube closure and gastrulation defects, representing ciliary and non-ciliary functions of PACRG. Conclusions The PACRG protein is a novel essential factor of cilia in Xenopus.
Collapse
Affiliation(s)
- Thomas Thumberger
- Institute of Zoology, Working group Embryology, University of Hohenheim, Garbenstraße 30, Stuttgart, 70593, Germany.
| | | | | | | | | | | | | | | |
Collapse
|
35
|
Li L, Wen L, Gong Y, Mei G, Liu J, Chen Y, Peng T. Xenopus as a model system for the study of GOLPH2/GP73 function: Xenopus GOLPH2 is required for pronephros development. PLoS One 2012; 7:e38939. [PMID: 22719994 PMCID: PMC3375297 DOI: 10.1371/journal.pone.0038939] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2012] [Accepted: 05/14/2012] [Indexed: 12/28/2022] Open
Abstract
GOLPH2 is a highly conserved protein. It is upregulated in a number of tumors and is being considered as an emerging biomarker for related diseases. However, the function of GOLPH2 remains unknown. The Xenopus model is used to study the function of human proteins. We describe the isolation and characterization of Xenopus golph2, which dimerizes and localizes to the Golgi in a manner similar to human GOLPH2. Xenopus golph2 is expressed in the pronephros during early development. The morpholino-mediated knockdown of golph2 results in edema formation. Additionally, Nephrin expression is enhanced in the glomus, and the expression of pronephric marker genes, such as atp1b1, ClC-K, NKCC2, and NBC1, is diminished in the tubules and duct. Expression patterns of the transcription factors WT1, Pax2, Pax8, Lim1, GATA3, and HNF1β are also examined in the golph2 knockdown embryos, the expression of WT1 is increased in the glomus and expanded laterally in the pronephric region. We conclude that the deletion of golph2 causes an increase in the expression of WT1, which may promote glomus formation and inhibit pronephric tubule differentiation.
Collapse
Affiliation(s)
- Leike Li
- State Key Laboratory of Respiratory Disease, Guangzhou Institute of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, China
- University of Science and Technology of China, Hefei, China
| | - Luan Wen
- Key Laboratory of Regenerative Biology, Guangzhou Institute of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, China
- Section on Molecular Morphogenesis, Laboratory of Gene Regulation and Development, Program in Cellular Regulation and Metabolism, Eunice Kennedy Shriver National Institute Child Health and Human Development, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Yu Gong
- State Key Laboratory of Respiratory Disease, Guangzhou Institute of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, China
| | - Guoqiang Mei
- State Key Laboratory of Respiratory Disease, Guangzhou Institute of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, China
- University of Science and Technology of China, Hefei, China
| | - Jinsong Liu
- State Key Laboratory of Respiratory Disease, Guangzhou Institute of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, China
| | - Yonglong Chen
- Key Laboratory of Regenerative Biology, Guangzhou Institute of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, China
- * E-mail: (TP); (YC)
| | - Tao Peng
- State Key Laboratory of Respiratory Disease, Guangzhou Institute of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, China
- University of Science and Technology of China, Hefei, China
- * E-mail: (TP); (YC)
| |
Collapse
|
36
|
The Bic-C family of developmental translational regulators. Comp Funct Genomics 2012; 2012:141386. [PMID: 22611335 PMCID: PMC3352585 DOI: 10.1155/2012/141386] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2012] [Accepted: 02/18/2012] [Indexed: 12/14/2022] Open
Abstract
Regulation of mRNA translation is especially important during cellular and developmental processes. Many evolutionarily conserved proteins act in the context of multiprotein complexes and modulate protein translation both at the spatial and the temporal levels. Among these, Bicaudal C constitutes a family of RNA binding proteins whose founding member was first identified in Drosophila and contains orthologs in vertebrates. We discuss recent advances towards understanding the functions of these proteins in the context of the cellular and developmental biology of many model organisms and their connection to human disease.
Collapse
|
37
|
Walentek P, Beyer T, Thumberger T, Schweickert A, Blum M. ATP4a Is Required for Wnt-Dependent Foxj1 Expression and Leftward Flow in Xenopus Left-Right Development. Cell Rep 2012; 1:516-27. [DOI: 10.1016/j.celrep.2012.03.005] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2011] [Revised: 03/06/2012] [Accepted: 03/21/2012] [Indexed: 12/12/2022] Open
|
38
|
Heat-shock mediated overexpression of HNF1β mutations has differential effects on gene expression in the Xenopus pronephric kidney. PLoS One 2012; 7:e33522. [PMID: 22438943 PMCID: PMC3305329 DOI: 10.1371/journal.pone.0033522] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2011] [Accepted: 02/15/2012] [Indexed: 02/07/2023] Open
Abstract
The transcription factor HNF1B, encoded by the TCF2 gene, plays an important role in the organogenesis of vertebrates. In humans, heterozygous mutations of HNF1B are associated with several diseases, such as pancreatic β-cell dysfunction leading to maturity-onset diabetes of the young (MODY5), defective kidney development, disturbed liver function, pancreas atrophy, and malformations of the genital tract. The African claw frog Xenopus laevis is an excellent model to study the processes involved in embryogenesis and organogenesis, as it can be manipulated easily with a series of methods. In the present study, we overexpressed HNF1β mutants in the developing Xenopus embryo to assess their roles during organogenesis, particularly in the developing pronephric kidney. Towards this goal, we developed a heat-shock inducible binary Cre/loxP system with activator and effector strains. Heat-shock activation of the mutant HNF1B variants P328L329del and A263insGG resulted in malformations of various organs and the affected larvae developed large edemas. Defects in the pronephros were primarily confined to malformed proximal tubules. Furthermore, the expression of the proximal tubule marker genes tmem27 and slc3a1, both involved in amino acid transport, was affected. Both P328L329del and A263insGG downregulated expression of slc3a1. In addition, P328L329del reduced tmem27 expression while A263insGG overexpression decreased expression of the chloride channel clcnk and the transcription factor pax2. Overexpression of two mutant HNF1B derivatives resulted in distinct phenotypes reflected by either a reduction or an enlargement of pronephros size. The expression of selected pronephric marker genes was differentially affected upon overexpression of HNF1B mutations. Based on our findings, we postulate that HNF1B mutations influence gene regulation upon overexpression in specific and distinct manners. Furthermore, our study demonstrates that the newly established Cre/loxP system for Xenopus embryos is an attractive alternative to examine the gene regulatory potential of transcription factors in developing pronephric kidney as exemplified here for HNF1B.
Collapse
|
39
|
Abstract
MicroRNAs (miRNAs) are endogenous short (20-22 nucleotides) non-coding RNA molecules that mediate gene expression. This is an important regulatory mechanism to modulate fundamental cellular processes such as differentiation, proliferation, death, metabolism, and pathophysiology of many diseases. The miRNA expression profile of the kidney differs greatly from that of other organs, as well as between the different regions in the kidney. In kidneys, miRNAs are indispensable for development and homeostasis. In this review, we explore the involvement of miRNAs in the regulation of blood pressure, hormone, water, and ion balance pertaining to kidney homeostasis. We also highlight their importance in renal pathophysiology, such as in polycystic disease, diabetic nephropathy, nephrogenic diabetes insipidus, hypertension, renal cancer, and kidney fibrosis (epithelial-mesenchymal transition). In addition, we highlight the need for further investigations on miRNA-based studies in the development of diagnostic, prognostic, and therapeutic tools for renal diseases.
Collapse
|
40
|
Pescadillo homologue 1 and Peter Pan function during Xenopus laevis pronephros development. Biol Cell 2011; 103:483-98. [PMID: 21770895 DOI: 10.1042/bc20110032] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
BACKGROUND INFORMATION pes1 (pescadillo homologue 1) and ppan (Peter Pan) are multifunctional proteins involved in ribosome biogenesis, cell proliferation, apoptosis, cell migration and regulation of gene expression. Both proteins are required for early neural development in Xenopus laevis, as previously demonstrated. RESULTS We show that the expression of both genes in the developing pronephros depends on wnt4 and fzd3 (frizzled homologue 3) function. Loss of pes1 or ppan by MO (morpholino oligonucleotide)-based knockdown approaches resulted in strong malformations during pronephric tubule formation. Defects were already notable during specification of pronephric progenitor cells, as shown by lhx1 expression. Moreover, we demonstrated that Xenopus pes1 and ppan interact physically and functionally and that pes1 and ppan can cross-rescue the loss of function phenotype of one another. Interference with rRNA synthesis, however, did not result in a similar early pronephros phenotype. CONCLUSION These results demonstrate that pes1 and ppan are required for Xenopus pronephros development and indicate that their function in the pronephros is independent of their role in ribosome biosynthesis.
Collapse
|
41
|
Zhang B, Tran U, Wessely O. Expression of Wnt signaling components during Xenopus pronephros development. PLoS One 2011; 6:e26533. [PMID: 22028899 PMCID: PMC3197532 DOI: 10.1371/journal.pone.0026533] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2011] [Accepted: 09/28/2011] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND The formation of the vertebrate kidney is tightly regulated and relies on multiple evolutionarily conserved inductive events. These are present in the complex metanephric kidney of higher vertebrates, but also in the more primitive pronephric kidney functional in the larval stages of amphibians and fish. Wnts have long been viewed as central in this process. Canonical β-Catenin-dependent Wnt signaling establishes kidney progenitors and non-canonical β-Catenin-independent Wnt signaling participate in the morphogenetic processes that form the highly sophisticated nephron structure. While some individual Wnt signaling components have been studied extensively in the kidney, the overall pathway has not yet been analyzed in depth. METHODOLOGY/PRINCIPAL FINDINGS Here we report a detailed expression analysis of all Wnt ligands, receptors and several downstream Wnt effectors during pronephros development in Xenopus laevis using in situ hybridization. Out of 19 Wnt ligands, only three, Wnt4, Wnt9a and Wnt11, are specifically expressed in the pronephros. Others such as Wnt8a are present, but in a broader domain comprising adjacent tissues in addition to the kidney. The same paradigm is observed for the Wnt receptors and its downstream signaling components. Fzd1, Fzd4, Fzd6, Fzd7, Fzd8 as well as Celsr1 and Prickle1 show distinct expression domains in the pronephric kidney, whereas the non-traditional Wnt receptors, Ror2 and Ryk, as well as the majority of the effector molecules are rather ubiquitous. In addition to this spatial regulation, the timing of expression is also tightly regulated. In particular, non-canonical Wnt signaling seems to be restricted to later stages of pronephros development. CONCLUSION/SIGNIFICANCE Together these data suggest a complex cross talk between canonical and non-canonical Wnt signaling is required to establish a functional pronephric kidney.
Collapse
Affiliation(s)
- Bo Zhang
- Lerner Research Institute/Cleveland Clinic, Department of Cell Biology, Cleveland, Ohio, United States of America
- Louisiana State University (LSU) Health Sciences Center, Department of Cell Biology & Anatomy, New Orleans, Louisiana, United States of America
| | - Uyen Tran
- Lerner Research Institute/Cleveland Clinic, Department of Cell Biology, Cleveland, Ohio, United States of America
| | - Oliver Wessely
- Lerner Research Institute/Cleveland Clinic, Department of Cell Biology, Cleveland, Ohio, United States of America
- * E-mail:
| |
Collapse
|
42
|
Wessely O, Tran U. Xenopus pronephros development--past, present, and future. Pediatr Nephrol 2011; 26:1545-51. [PMID: 21499947 PMCID: PMC3425949 DOI: 10.1007/s00467-011-1881-2] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/05/2010] [Revised: 12/08/2010] [Accepted: 12/14/2010] [Indexed: 11/30/2022]
Abstract
Kidney development is a multi-step process where undifferentiated mesenchyme is converted into a highly complex organ through several inductive events. The general principles regulating these events have been under intense investigation and despite extensive progress, many open questions remain. While the metanephric kidneys of mouse and rat have served as the primary model, other organisms also significantly contribute to the field. In particular, the more primitive pronephric kidney has emerged as an alternative model due to its simplicity and experimental accessibility. Many aspects of nephron development such as the patterning along its proximo-distal axis are evolutionarily conserved and are therefore directly applicable to higher vertebrates. This review will focus on the current understanding of pronephros development in Xenopus. It summarizes how signaling, transcriptional regulation, as well as post-transcriptional mechanisms contribute to the differentiation of renal epithelial cells. The data show that even in the simple pronephros the mechanisms regulating kidney organogenesis are highly complex. It also illustrates that a multifaceted analysis embracing modern genome-wide approaches combined with single gene analysis will be required to fully understand all the intricacies.
Collapse
Affiliation(s)
- Oliver Wessely
- Department of Cell Biology & Anatomy, LSU Health Sciences Center, New Orleans, LA, USA.
| | - Uyen Tran
- LSU Health Sciences Center, Department of Cell Biology & Anatomy, MEB 6A12, 1901 Perdido Street, New Orleans, LA 70112, USA
| |
Collapse
|
43
|
Kerner P, Degnan SM, Marchand L, Degnan BM, Vervoort M. Evolution of RNA-binding proteins in animals: insights from genome-wide analysis in the sponge Amphimedon queenslandica. Mol Biol Evol 2011; 28:2289-303. [PMID: 21325094 DOI: 10.1093/molbev/msr046] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
RNA-binding proteins (RBPs) are key players in various biological processes, most notably regulation of gene expression at the posttranscriptional level. Although many RBPs have been carefully studied in model organisms, very few studies have addressed the evolution of these proteins at the scale of the animal kingdom. We identified a large set of putative RBPs encoded by the genome of the demosponge Amphimedon queenslandica, a species representing a basal animal lineage. We compared the Amphimedon RBPs with those encoded by the genomes of two bilaterians (human and Drosophila), representatives of two other basal metazoan lineages (a placozoan and a cnidarian), a choanoflagellate (probable sister group of animals), and two fungi. We established the evolutionary history of 32 families of RBPs and found that most of the diversity of RBPs present in contemporary metazoans, including humans, was already established in the last common ancestor (LCA) of animals. This includes RBPs known to be involved in key processes in bilaterians, such as development, stem and/or germ cells properties, and noncoding RNA pathways. From this analysis, we infer that a complex toolkit of RBPs was present in the LCA of animals and that it has been recruited to perform new functions during early animal evolution, in particular in relation to the acquisition of multicellularity.
Collapse
Affiliation(s)
- Pierre Kerner
- Development and Neurobiology Programme, Institut Jacques Monod, Centre national de la recherche scientifique/Université Paris Diderot-Paris 7, Paris cedex, France
| | | | | | | | | |
Collapse
|
44
|
Inversin relays Frizzled-8 signals to promote proximal pronephros development. Proc Natl Acad Sci U S A 2010; 107:20388-93. [PMID: 21059920 DOI: 10.1073/pnas.1013070107] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Mutations of inversin cause type II nephronophthisis, an infantile autosomal recessive disease characterized by cystic kidney disease and developmental defects. Inversin regulates Wnt signaling and is required for convergent extension movements during early embryogenesis. We now show that Inversin is essential for Xenopus pronephros formation, involving two distinct and opposing forms of cell movements. Knockdown of Inversin abrogated both proximal pronephros extension and distal tubule differentiation, phenotypes similar to that of Xenopus deficient in Frizzled-8. Exogenous Inversin rescued the pronephric defects caused by lack of Frizzled-8, indicating that Inversin acts downstream of Frizzled-8 in pronephros morphogenesis. Depletion of Inversin prevents the recruitment of Dishevelled in response to Frizzled-8 and impeded the accumulation of Dishevelled at the apical membrane of tubular epithelial cells in vivo. Thus, defective tubule morphogenesis seems to contribute to the renal pathology observed in patients with nephronophthisis type II.
Collapse
|
45
|
Tiermodelle mit Zystennieren. MED GENET-BERLIN 2010. [DOI: 10.1007/s11825-010-0230-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Zusammenfassung
Polyzystische Nierenerkrankungen (PKD) sind der häufigste genetische Grund für ein terminales Nierenversagen. Flüssigkeitsgefüllte Zysten bilden sich im Nierenparenchym und beeinträchtigen die Nierenfunktion mit zunehmender Anzahl und Größe, bis diese vollkommen zum Erliegen kommt. Seit mehreren Jahrzehnten werden Tiermodelle mit PKD für die Aufklärung der molekularen Mechanismen der Zystogenese verwendet. War man anfangs auf zufällige, durch Spontanmutationen aufgetretene Zystenmodelle angewiesen, eröffneten transgene und Knock-out-Technologien in den letzen 20 Jahren eine völlig neue Dimension, die molekularen Pathomechanismen der Zystogenese durch gezielte genetische Veränderungen im Erbgut aufzuklären. Nur mit der Hilfe von Tiermodellen konnte die Lokalisation von „Zystenproteinen“ in den Zilien und die Beteiligung zilienabhängiger Signalkaskaden in der Zystogenese gezeigt werden. Dieser Artikel gibt einen Überblick über die derzeit vorhandenen murinen Tiermodelle mit PKD.
Collapse
|
46
|
Nagao S, Morita M, Kugita M, Yoshihara D, Yamaguchi T, Kurahashi H, Calvet JP, Wallace DP. Polycystic kidney disease in Han:SPRD Cy rats is associated with elevated expression and mislocalization of SamCystin. Am J Physiol Renal Physiol 2010; 299:F1078-86. [PMID: 20719982 DOI: 10.1152/ajprenal.00504.2009] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Polycystic kidney disease (PKD) in Han:SPRD Cy rats is caused by a missense mutation in Anks6 (also called Pkdr1), leading to an R823W substitution in SamCystin, a protein that contains ankyrin repeats and a sterile alpha motif (SAM). The cellular function of SamCystin and the role of the Cy (R823W) mutation in cyst formation are unknown. In normal SPRD rats, SamCystin was found to be expressed in proximal tubules and glomeruli; protein expression was highest at 7 days of age and declined by ∼50-60% at 45-84 days of age. In Cy/+ and Cy/Cy kidneys, expression of SamCystin was lower than in +/+ kidneys at 3 and 7 days but became elevated at 21 days. Immunohistochemical analysis revealed that SamCystin was distributed on the brush border of proximal tubules in normal rat kidneys. In Cy/+ kidneys, there were robust SamCystin staining in cyst-lining epithelial cells and loss of apical localization, and increased number of PCNA-positive cells in cyst-lining epithelia. Verapamil, an L-type Ca(2+) channel blocker, accelerated PKD progression in this model and caused a further increase in the expression and abnormal distribution of SamCystin. We conclude that aberrant expression and mislocalization of R823W SamCystin lead to increased cell proliferation and renal cyst formation.
Collapse
Affiliation(s)
- Shizuko Nagao
- The Kidney Institute, Dept. of Medicine, Univ. of Kansas Medical Center, 3901 Rainbow Blvd., Kansas City, KS 66160-3018, USA
| | | | | | | | | | | | | | | |
Collapse
|
47
|
Fu Y, Kim I, Lian P, Li A, Zhou L, Li C, Liang D, Coffey RJ, Ma J, Zhao P, Zhan Q, Wu G. Loss of Bicc1 impairs tubulomorphogenesis of cultured IMCD cells by disrupting E-cadherin-based cell-cell adhesion. Eur J Cell Biol 2010; 89:428-36. [PMID: 20219263 PMCID: PMC2886128 DOI: 10.1016/j.ejcb.2010.01.002] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2009] [Revised: 01/20/2010] [Accepted: 01/28/2010] [Indexed: 01/12/2023] Open
Abstract
The Bicaudal-C (Bic-C) gene was originally discovered in Drosophila melanogaster. The gene product Bic-C is thought to serve as an RNA-binding molecule targeting diverse proteins at the post-transcriptional level. Recent research has shown this gene to be conserved in many species, from Caenorhabditis elegans to humans. Disruption of this protein can disturb the normal migration direction of the anterior follicle cell of Drosophila oocytes, while mutation of a mouse Bicc1 (a mouse homologue of Bic-C) results in phenotypes mimicking human hereditary polycystic kidney disease (PKD). However, the cellular function of Bicc1 gene products in mammalian systems remains largely unknown. In this study, we established stable IMCD (mouse inner medullary collecting duct) cell lines, in which Bicc1 was silenced by short hairpin RNA inhibition (shRNA). We show that inhibition of Bicc1 disrupted normal tubulomorphogenesis and induced cystogenesis of IMCD cells grown in three dimensional cultures. To determine what factors contributed to the defect, we systematically examined biological changes of Bicc1-silenced IMCD cells. We found that the cells had significant defects in E-cadherin-based cell-cell adhesion, along with abnormalities in actin cytoskeleton organization, cell-extracellular matrix interactions, cell proliferation, and apoptosis. These findings suggest that lack of Bicc1 leads to disruption of normal cell-cell junctions, which in turn impedes establishment of epithelial polarity. These cellular defects may initiate abnormal tubulomorphogenesis and cystogenesis of IMCD cells grown in vitro. The observation of aberrant cellular behaviors in Bicc1-silenced IMCD cells reveal functions for Bicc1 in renal epithelial cells and provides insight into a potential pathogenic mechanism of polycystic kidney disease.
Collapse
Affiliation(s)
- Yulong Fu
- Division of Translational Cancer Research and Therapy, State Key Laboratory of Molecular Oncology, Cancer Hospital and Institute, Chinese Academy of Medical Sciences, Beijing 100021, China
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
48
|
White JT, Zhang B, Cerqueira DM, Tran U, Wessely O. Notch signaling, wt1 and foxc2 are key regulators of the podocyte gene regulatory network in Xenopus. Development 2010; 137:1863-73. [PMID: 20431116 PMCID: PMC2867321 DOI: 10.1242/dev.042887] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/24/2010] [Indexed: 11/20/2022]
Abstract
Podocytes are highly specialized cells in the vertebrate kidney. They participate in the formation of the size-exclusion barrier of the glomerulus/glomus and recruit mesangial and endothelial cells to form a mature glomerulus. At least six transcription factors (wt1, foxc2, hey1, tcf21, lmx1b and mafb) are known to be involved in podocyte specification, but how they interact to drive the differentiation program is unknown. The Xenopus pronephros was used as a paradigm to address this question. All six podocyte transcription factors were systematically eliminated by antisense morpholino oligomers. Changes in the expression of the podocyte transcription factors and of four selected markers of terminal differentiation (nphs1, kirrel, ptpru and nphs2) were analyzed by in situ hybridization. The data were assembled into a transcriptional regulatory network for podocyte development. Although eliminating the six transcription factors individually interfered with aspects of podocyte development, no single gene regulated the entire differentiation program. Only the combined knockdown of wt1 and foxc2 resulted in a loss of all podocyte marker gene expression. Gain-of-function studies showed that wt1 and foxc2 were sufficient to increase podocyte gene expression within the glomus proper. However, the combination of wt1, foxc2 and Notch signaling was required for ectopic expression in ventral marginal zone explants. Together, this approach demonstrates how complex interactions are required for the correct spatiotemporal execution of the podocyte gene expression program.
Collapse
Affiliation(s)
- Jeffrey T. White
- Department of Cell Biology and Anatomy, LSU Health Sciences Center, MEB 6A12, 1901 Perdido Street, New Orleans, LA 70112, USA
| | - Bo Zhang
- Department of Cell Biology and Anatomy, LSU Health Sciences Center, MEB 6A12, 1901 Perdido Street, New Orleans, LA 70112, USA
| | - Débora M. Cerqueira
- Department of Cell Biology and Anatomy, LSU Health Sciences Center, MEB 6A12, 1901 Perdido Street, New Orleans, LA 70112, USA
| | - Uyen Tran
- Department of Cell Biology and Anatomy, LSU Health Sciences Center, MEB 6A12, 1901 Perdido Street, New Orleans, LA 70112, USA
| | - Oliver Wessely
- Department of Cell Biology and Anatomy, LSU Health Sciences Center, MEB 6A12, 1901 Perdido Street, New Orleans, LA 70112, USA
- Department of Genetics, LSU Health Sciences Center, MEB 6A12, 1901 Perdido Street, New Orleans, LA 70112, USA
| |
Collapse
|
49
|
Haugan BM, Halberg KA, Jespersen A, Prehn LR, Møbjerg N. Functional characterization of the vertebrate primary ureter: structure and ion transport mechanisms of the pronephric duct in axolotl larvae (Amphibia). BMC DEVELOPMENTAL BIOLOGY 2010; 10:56. [PMID: 20507566 PMCID: PMC2891660 DOI: 10.1186/1471-213x-10-56] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/18/2009] [Accepted: 05/27/2010] [Indexed: 11/10/2022]
Abstract
BACKGROUND Three kidney systems appear during vertebrate development: the pronephroi, mesonephroi and metanephroi. The pronephric duct is the first or primary ureter of these kidney systems. Its role as a key player in the induction of nephrogenic mesenchyme is well established. Here we investigate whether the duct is involved in urine modification using larvae of the freshwater amphibian Ambystoma mexicanum (axolotl) as model. RESULTS We investigated structural as well as physiological properties of the pronephric duct. The key elements of our methodology were: using histology, light and transmission electron microscopy as well as confocal laser scanning microscopy on fixed tissue and applying the microperfusion technique on isolated pronephric ducts in combination with single cell microelectrode impalements. Our data show that the fully differentiated pronephric duct is composed of a single layered epithelium consisting of one cell type comparable to the principal cell of the renal collecting duct system. The cells are characterized by a prominent basolateral labyrinth and a relatively smooth apical surface with one central cilium. Cellular impalements demonstrate the presence of apical Na+ and K+ conductances, as well as a large K+ conductance in the basolateral cell membrane. Immunolabeling experiments indicate heavy expression of Na+/K+-ATPase in the basolateral labyrinth. CONCLUSIONS We propose that the pronephric duct is important for the subsequent modification of urine produced by the pronephros. Our results indicate that it reabsorbs sodium and secretes potassium via channels present in the apical cell membrane with the driving force for ion movement provided by the Na+/K+ pump. This is to our knowledge the first characterization of the pronephric duct, the precursor of the collecting duct system, which provides a model of cell structure and basic mechanisms for ion transport. Such information may be important in understanding the evolution of vertebrate kidney systems and human diseases associated with congenital malformations.
Collapse
Affiliation(s)
- Birgitte M Haugan
- Department of Biology, University of Copenhagen, Universitetsparken, DK-2100 Copenhagen, Denmark
| | | | | | | | | |
Collapse
|
50
|
Tran U, Zakin L, Schweickert A, Agrawal R, Döger R, Blum M, De Robertis EM, Wessely O. The RNA-binding protein bicaudal C regulates polycystin 2 in the kidney by antagonizing miR-17 activity. Development 2010; 137:1107-16. [PMID: 20215348 DOI: 10.1242/dev.046045] [Citation(s) in RCA: 119] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
The RNA-binding protein Bicaudal C is an important regulator of embryonic development in C. elegans, Drosophila and Xenopus. In mouse, bicaudal C (Bicc1) mutants are characterized by the formation of fluid-filled cysts in the kidney and by expansion of epithelial ducts in liver and pancreas. This phenotype is reminiscent of human forms of polycystic kidney disease (PKD). Here, we now provide data that Bicc1 functions by modulating the expression of polycystin 2 (Pkd2), a member of the transient receptor potential (TRP) superfamily. Molecular analyses demonstrate that Bicc1 acts as a post-transcriptional regulator upstream of Pkd2. It regulates the stability of Pkd2 mRNA and its translation efficiency. Bicc1 antagonized the repressive activity of the miR-17 microRNA family on the 3'UTR of Pkd2 mRNA. This was substantiated in Xenopus, in which the pronephric defects of bicc1 knockdowns were rescued by reducing miR-17 activity. At the cellular level, Bicc1 protein is localized to cytoplasmic foci that are positive for the P-body markers GW182 and HEDLs. Based on these data, we propose that the kidney phenotype in Bicc1(-/-) mutant mice is caused by dysregulation of a microRNA-based translational control mechanism.
Collapse
Affiliation(s)
- Uyen Tran
- Department of Cell Biology & Anatomy, LSU Health Sciences Center, MEB 6A12, 1901 Perdido Street, New Orleans, LA 70112, USA
| | | | | | | | | | | | | | | |
Collapse
|