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Anatomy and Embryology 1990The regression of the pronephric kidney of the lamprey, Petromyzon marinus, is described using histochemical and ultrastructural techniques. Regression begins in the...
The regression of the pronephric kidney of the lamprey, Petromyzon marinus, is described using histochemical and ultrastructural techniques. Regression begins in the third year of larval life, and by the time the animal enters metamorphosis the tubules have all disappeared. The nephrostomes and the renal corpuscle, however, persist for the remainder of the life cycle and undergo little change in the larva. Iron is present within the tubular epithelium prior to the beginning of degeneration, but as degeneration proceeds iron is observed within the tubule lumina. Acid phosphatase is noted within the tubule epithelia prior to degeneration, but as degeneration proceeds acid phosphatase is also observed within the intertubular area. Features of tubular regression include a prominent and highly folded basal lamina, numerous cytoplasmic inclusions, and dense bodies in the epithelia and lumina. The intertubular region is invaded by lymphocytes, granulocytes, plasma cells, and macrophages. The process of pronephric regression possesses many features of the process of apoptosis, which has been noted in the regression of larval organs in other vertebrates.
Topics: Acid Phosphatase; Animals; Cell Survival; Iron; Kidney; Kidney Tubules; Lampreys; Larva; Microscopy, Electron
PubMed: 2240593
DOI: 10.1007/BF00187526 -
PLoS Genetics Jan 2007Pronephros, a developmental model for adult mammalian kidneys (metanephros) and a functional kidney in early teleosts, consists of glomerulus, tubule, and duct. These...
Pronephros, a developmental model for adult mammalian kidneys (metanephros) and a functional kidney in early teleosts, consists of glomerulus, tubule, and duct. These structural and functional elements are responsible for different kidney functions, e.g., blood filtration, waste extraction, salt recovery, and water balance. During pronephros organogenesis, cell differentiation is a key step in generating different cell types in specific locations to accomplish designated functions. However, it is poorly understood what molecules regulate the differentiation of different cell types in different parts of the kidney. Two types of epithelial cells, multi-cilia cells and principal cells, are found in the epithelia of the zebrafish distal pronephric duct. While the former is characterized by at least 15 apically localized cilia and expresses centrin2 and rfx2, the latter is characterized by a single primary cilium and sodium pumps. Multi-cilia cells and principal cells differentiate from 17.5 hours post-fertilization onwards in a mosaic pattern. Jagged2a-Notch1a/Notch3-Her9 is responsible for specification and patterning of these two cell types through a lateral inhibition mechanism. Furthermore, multi-cilia cell hyperplasia was observed in mind bomb mutants and Mind bomb was shown to interact with Jagged2a and facilitate its internalization. Taken together, our findings add a new paradigm of Notch signaling in kidney development, namely, that Jagged2a-Notch signaling modulates cell fate choice in a nephric segment, the distal pronephric duct.
Topics: Animals; Calcium-Binding Proteins; Cell Differentiation; Cell Lineage; Gene Expression Regulation, Developmental; Jagged-2 Protein; Kidney; Microscopy, Electron, Transmission; Molecular Sequence Data; Receptors, Notch; Signal Transduction; Zebrafish; Zebrafish Proteins
PubMed: 17257056
DOI: 10.1371/journal.pgen.0030018 -
Developmental Dynamics : An Official... Jun 2011Low-density lipoprotein receptor-related protein 2 (LRP2) is a multifunctional cell surface receptor conserved from nematodes to humans. In mammals, it acts as regulator...
Low-density lipoprotein receptor-related protein 2 (LRP2) is a multifunctional cell surface receptor conserved from nematodes to humans. In mammals, it acts as regulator of sonic hedgehog and bone morphogenetic protein pathways in patterning of the embryonic forebrain and as a clearance receptor in the adult kidney. Little is known about activities of this LRP in other phyla. Here, we extend the functional elucidation of LRP2 to zebrafish as a model organism of receptor (dys)function. We demonstrate that expression of Lrp2 in embryonic and larval fish recapitulates the patterns seen in mammalian brain and kidney. Furthermore, we studied the consequence of receptor deficiencies in lrp2 and in lrp2b, a homologue unique to fish, using ENU mutagenesis or morpholino knockdown. While receptor-deficient zebrafish suffer from overt renal resorption deficiency, their brain development proceeds normally, suggesting evolutionary conservation of receptor functions in pronephric duct clearance but not in patterning of the teleost forebrain.
Topics: Animals; Animals, Genetically Modified; Body Patterning; Gene Deletion; Gene Expression Regulation, Developmental; Kidney Tubules; Low Density Lipoprotein Receptor-Related Protein-2; Metabolic Clearance Rate; Models, Biological; Phylogeny; Prosencephalon; Protein Structure, Tertiary; Signal Transduction; Zebrafish
PubMed: 21455927
DOI: 10.1002/dvdy.22624 -
Developmental Biology Jul 1982
Topics: Ambystoma; Animals; Embryo, Nonmammalian; Kidney; Kidney Transplantation; Microscopy, Electron, Scanning; Transplantation, Autologous
PubMed: 7049791
DOI: 10.1016/0012-1606(82)90159-2 -
Genesis (New York, N.Y. : 2000) 2015The vertebrate kidney plays an essential role in removing metabolic waste and balancing water and salt. This is carried out by nephrons, which comprise a blood filter...
The vertebrate kidney plays an essential role in removing metabolic waste and balancing water and salt. This is carried out by nephrons, which comprise a blood filter attached to an epithelial tubule with proximal and distal segments. In zebrafish, two nephrons are first formed as part of the embryonic kidney (pronephros) and hundreds are formed later to make up the adult kidney (mesonephros). Previous studies have focused on the development of the pronephros while considerably less is known about how the mesonephros is formed. Here, we characterize mesonephros development in zebrafish and examine the nephrons that form during larval metamorphosis. These nephrons, arising from proliferating progenitor cells that express the renal transcription factor genes wt1b, pax2a, and lhx1a, form on top of the pronephric tubules and develop a segmentation pattern similar to pronephric nephrons. We find that the pronephros acts as a scaffold for the mesonephros, where new nephrons fuse with the distal segments of the pronephric tubules to form the final branching network that characterizes the adult zebrafish kidney.
Topics: Animals; Embryo, Nonmammalian; Gene Expression Regulation, Developmental; Immunoenzyme Techniques; In Situ Hybridization; Kidney; Mesonephros; Metamorphosis, Biological; Nephrons; Organogenesis; Pronephros; Zebrafish; Zebrafish Proteins
PubMed: 25677367
DOI: 10.1002/dvg.22846 -
Nephron. Experimental Nephrology 2003The development of the first form of kidney, the pronephros, in the frog Xenopus is most attractive to study nephrogenesis in vertebrates. The formation of the... (Review)
Review
The development of the first form of kidney, the pronephros, in the frog Xenopus is most attractive to study nephrogenesis in vertebrates. The formation of the pronephros can be readily analyzed during organogenesis by manipulating the activity of specific factors in the developing Xenopus embryo. In addition embryonic explants of Xenopus can be induced to pronephric differentiation in vitro by adding defined signaling molecules. The available data show that the same transcription factors and signaling molecules play a role in Xenopus pronephros differentiation as in mammalian nephrogenesis. This allows the dissection of the molecular and cellular events relevant for nephrogenesis in an easy amenable experimental system. Thus, Xenopus pronephros formation can be used to define nephrogenic regulators and to identify the morphogenetic potential of mutated factors associated with renal diseases in humans.
Topics: Animals; Humans; Kidney; Xenopus
PubMed: 12845229
DOI: 10.1159/000071282 -
Mechanisms of Development Jul 2002We have isolated a zebrafish cadherin that is orthologous to human LI-cadherin (CDH17). Zebrafish cdh17 is expressed exclusively in the pronephric ducts during...
We have isolated a zebrafish cadherin that is orthologous to human LI-cadherin (CDH17). Zebrafish cdh17 is expressed exclusively in the pronephric ducts during embryogenesis, and in the mesonephros during larval development and adulthood. Like its mammalian ortholog, cdh17 is also expressed in liver and intestine in adult zebrafish. We show that cdh17-positive mesodermal cells do not contribute to the hematopoietic system. Consistent with a cell adhesion role for Cdh17, depletion of Cdh17 function using antisense morpholino oligonucleotides compromised cell cohesion during pronephric duct formation. Our results indicate that Cdh17 is necessary for maintaining the integrity of the pronephric ducts during zebrafish embryogenesis. This finding contrasts with the role of mammalian CDH17, which does not appear to be involved in nephric development.
Topics: Amino Acid Sequence; Animals; Biomarkers; Cadherins; Carrier Proteins; DNA-Binding Proteins; Gene Expression; Humans; Kidney Tubules; Membrane Transport Proteins; Molecular Sequence Data; PAX2 Transcription Factor; Sequence Homology, Amino Acid; Tissue Distribution; Transcription Factors; WT1 Proteins; Zebrafish; Zebrafish Proteins
PubMed: 12049763
DOI: 10.1016/s0925-4773(02)00094-1 -
Developmental Dynamics : An Official... Feb 2005Peroxidasin, originally identified in Drosophila, is a member of the myeloperoxidase family with a novel domain structure. It is proposed that peroxidasin is secreted...
Peroxidasin, originally identified in Drosophila, is a member of the myeloperoxidase family with a novel domain structure. It is proposed that peroxidasin is secreted and has functions associated with stabilization of the extracellular matrix. We report the identification of the Xenopus tropicalis orthologue of the peroxidasin gene. We show that the predicted protein sequence of Xenopus peroxidasin shows high sequence identity with the human orthologue and that the exon structure is highly conserved between the two species. We describe the first detailed developmental expression pattern for peroxidasin in a vertebrate species. Maternal expression of Xtpxn is localized to the animal hemisphere where it persists through early cleavage stages. Initial zygotic Xtpxn expression is detected in the developing neural tube and becomes localized to the hindbrain and midbrain. Xtpxn is expressed in the primordium of the pronephric kidney and expression persists in the pronephric tubules and duct throughout development. Potential roles for peroxidasin during early vertebrate development are discussed.
Topics: Amino Acid Sequence; Animals; Antigens, Neoplasm; Blood Proteins; Conserved Sequence; DNA, Complementary; Drosophila; Eosinophil Major Basic Protein; Exons; Expressed Sequence Tags; Extracellular Matrix; Extracellular Matrix Proteins; Gene Expression Regulation, Developmental; Humans; In Situ Hybridization; Kidney; Mesencephalon; Models, Genetic; Molecular Sequence Data; Mothers; Nephrons; Neural Crest; Neurons; Peptides; Peroxidase; Peroxidases; Phylogeny; Protein Structure, Tertiary; Proteoglycans; Receptors, Interleukin-1; Reverse Transcriptase Polymerase Chain Reaction; Rhombencephalon; Sequence Homology, Amino Acid; Xenopus; Peroxidasin
PubMed: 15614763
DOI: 10.1002/dvdy.20226 -
The International Journal of... Aug 1996Pronephric duct (PND) morphogenesis is a critical early event in the development of the vertebrate excretory system. This structure is the exit channel for both...
Pronephric duct (PND) morphogenesis is a critical early event in the development of the vertebrate excretory system. This structure is the exit channel for both pronephric and mesonephric filtrate, forms the ureteric bud of the metanephros and gives rise to the ductus deferens of the testis. In addition, the PND and ureteric bud epithelia induce terminal differentiation of the mesonephric and metanephric mesenchyme, respectively. Elongation of the PND in all vertebrates involves active cell migration of the primordium. In urodele embryos--unlike in some anuran, avian and mammalian embryos--elongation of the PND occurs solely by cell migration. In the axolotl embryo, the PND primordium segregates as an ovoid tissue mass from the anterodorsal flank mesoderm directly beneath somites 3-7. The primordium then extends caudally along the ventral border of the developing somites until it reaches the cloaca. The ease with which these embryos can be manipulated microsurgically makes the PND system ideal for the study of the mechanisms controlling cell migration in vivo. This review summarizes the progress that has been made in characterizing the environmental cues and the cell surface recognition systems that drive this tightly regulated migration event.
Topics: Ambystoma; Animals; Cell Movement; Male; Morphogenesis; Vas Deferens
PubMed: 8877443
DOI: No ID Found -
Gene Jul 2003We isolated a novel cytokeratin gene of zebrafish (Danio rerio), DAPK-1 closely related to other vertebrate type I cytokeratin genes. Zygotic transcription starts at the...
We isolated a novel cytokeratin gene of zebrafish (Danio rerio), DAPK-1 closely related to other vertebrate type I cytokeratin genes. Zygotic transcription starts at the sphere stage. After the mid-blastula stage, DAPK-1 is expressed in all surface cells, notably in those of the outer enveloping layer. DAPK-1 messages are also present specifically during the segmentation, pharyngula, and hatching periods. In particular, after 24 h post-fertilization, its expression is restricted to the developing eye region, otic vesicle, pectoral fin, dorsal aorta, and pronephric duct. In the mindbomb mutant embryo that has defects in the dorsal aorta development, DAPK-1 transcripts are not detected in the dorsal aorta and pronephric duct. The characteristic expression pattern of DAPK-1 may facilitate more detailed studies related to the morphogenesis of dorsal aorta and pronephric duct.
Topics: Amino Acid Sequence; Animals; Aorta; DNA, Complementary; Embryo, Nonmammalian; Embryonic Development; Gene Expression Regulation, Developmental; Keratins; Kidney; Molecular Sequence Data; Mutation; Phylogeny; Sequence Alignment; Sequence Analysis, DNA; Zebrafish; Zebrafish Proteins
PubMed: 12909350
DOI: 10.1016/s0378-1119(03)00611-5