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Scientific Reports Oct 2023The nephron, functional unit of the vertebrate kidney, is specialized in metabolic wastes excretion and body fluids osmoregulation. Given the high evolutionary...
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.
Topics: Animals; Xenopus laevis; LIM-Homeodomain Proteins; Gene Expression Regulation, Developmental; Transcription Factors; Kidney; Embryonic Development; Morphogenesis; Pronephros; Xenopus Proteins; Mammals
PubMed: 37794075
DOI: 10.1038/s41598-023-43662-1 -
Anatomical Record (Hoboken, N.J. : 2007) Aug 2023This study aimed to describe pronephros and mesonephros morphology during the embryonic development of Podocnemis expansa. Eggs were collected on an artificial beach at...
This study aimed to describe pronephros and mesonephros morphology during the embryonic development of Podocnemis expansa. Eggs were collected on an artificial beach at Balbina, Amazonas, Brazil, during the entire incubation period (mean of 59 days). The kidney-gonad complex was processed using light microscopy and the mesonephros using transmission electron microscopy. The pronephros was present for the first time on stage 4, composed of external glomeruli devoid of a capsule, protruding into the coelomic cavity, and internally composed of a capillary network. The pronephros degenerated after development stage 15. The first sign of the appearance of the mesonephros occurred around stage 8, indicated by the early formation of renal corpuscles. The mesonephros comprised an renal corpuscles, neck segment, proximal tubule, intermediate segment, distal tubule, collector tubule, and collector duct. Ultrastructural analysis of the mesonephros brush border was done in the proximal tubule, and the presence of cells with structural characters indicative of secretory activity was detected in the juxtatubular region. Renal corpuscles and proximal tubules were the main components that underwent morphological alterations during mesonephros degeneration. The pronephros is a transient kidney, and the mesonephros became the functional embryonic kidney in P. expansa. Mesonephros degeneration occurs in the cranial-caudal direction, and histologically, the degeneration is identified by changes in the morphology of the renal corpuscle and proximal tubule. However, the mesonephros is still present after hatching.
Topics: Animals; Turtles; Mesonephros; Embryonic Development; Pronephros; Brazil
PubMed: 36573584
DOI: 10.1002/ar.25151 -
Scientific Reports Nov 2023The transcription factor Six2 plays a crucial role in maintaining self-renewing nephron progenitor cap mesenchyme (CM) during metanephric kidney development. In mouse...
The transcription factor Six2 plays a crucial role in maintaining self-renewing nephron progenitor cap mesenchyme (CM) during metanephric kidney development. In mouse and human, expression at single-cell resolution has detected Six2 in cells as they leave the CM pool and differentiate. The role Six2 may play in these cells as they differentiate remains unknown. Here, we took advantage of the zebrafish pronephric kidney which forms directly from intermediate mesoderm to test six2b function during pronephric tubule development and differentiation. Expression of six2b during early zebrafish development was consistent with a role in pronephros formation. Using morpholino knock-down and CRISPR/Cas9 mutagenesis, we show a functional role for six2b in the development of proximal elements of the pronephros. By 48 h post-fertilization, six2b morphants and mutants showed disrupted pronephric tubule morphogenesis. We observed a lower-than-expected frequency of phenotypes in six2b stable genetic mutants suggesting compensation. Supporting this, we detected increased expression of six2a in six2b stable mutant embryos. To further confirm six2b function, F crispant embryos were analyzed and displayed similar phenotypes as morphants and stable mutants. Together our data suggests a conserved role for Six2 during nephrogenesis and a role in the morphogenesis of the proximal tubule.
Topics: Animals; Humans; Mice; Morphogenesis; Nephrons; Pronephros; Zebrafish; Zebrafish Proteins
PubMed: 37952044
DOI: 10.1038/s41598-023-47046-3 -
Scientific Reports Nov 2023Messenger RNA (mRNA) therapies are emerging in different disease areas, but have not yet reached the kidney field. Our aim was to study the feasibility to treat the...
Messenger RNA (mRNA) therapies are emerging in different disease areas, but have not yet reached the kidney field. Our aim was to study the feasibility to treat the genetic defect in cystinosis using synthetic mRNA in cell models and ctns zebrafish embryos. Cystinosis is a prototype lysosomal storage disorder caused by mutations in the CTNS gene, encoding the lysosomal cystine-H symporter cystinosin, and leading to cystine accumulation in all cells of the body. The kidneys are the first and the most severely affected organs, presenting glomerular and proximal tubular dysfunction, progressing to end-stage kidney failure. The current therapeutic standard cysteamine, reduces cystine levels, but has many side effects and does not restore kidney function. Here, we show that synthetic mRNA can restore lysosomal cystinosin expression following lipofection into CTNS kidney cells and injection into ctns zebrafish. A single CTNS mRNA administration decreases cellular cystine accumulation for up to 14 days in vitro. In the ctns zebrafish, CTNS mRNA therapy improves proximal tubular reabsorption, reduces proteinuria, and restores brush border expression of the multi-ligand receptor megalin. Therefore, this proof-of-principle study takes the first steps in establishing an mRNA-based therapy to restore cystinosin expression, resulting in cystine reduction in vitro and in the ctns larvae, and restoration of the zebrafish pronephros function.
Topics: Animals; Cystinosis; Cystine; Zebrafish; RNA, Messenger; Models, Theoretical; Dietary Supplements; Amino Acid Transport Systems, Neutral
PubMed: 38016974
DOI: 10.1038/s41598-023-47085-w -
Development & Reproduction Sep 2023The Ruvb-like AAA ATPase1 (Ruvbl1; also known as Pontin) is an evolutionary conserved protein belonging to the adenosine triphosphates associated with diverse cellular...
The Ruvb-like AAA ATPase1 (Ruvbl1; also known as Pontin) is an evolutionary conserved protein belonging to the adenosine triphosphates associated with diverse cellular activities (AAA+) superfamily of ATPases. Ruvbl1 is a component of various protein supercomplexes and is involved in a variety of cellular activities, including chromatin remodeling, DNA damage repair, and mitotic spindle assembly however, the developmental significance of this protein is unknown and needs detailed investigation. We investigated the developmental significance of Ruvbl1 in multiciliated cells of the epidermis since is expressed in the multiciliated cells and pronephros during embryogenesis. The knockdown of significantly impaired cilia-driven fluid flow and basal body polarity in the epidermis compared to control embryos, but did not affect cilia morphology. Our results suggest that Ruvbl1 plays a significant role in embryonic development by regulating ciliary beating; however, further investigation is needed to determine the mechanisms involved.
PubMed: 38074458
DOI: 10.12717/DR.2023.27.3.159 -
Biochemical and Biophysical Research... Sep 2023Nephronophthisis (NPH), an autosomal recessive ciliopathy, results from mutations in more than 20 different genes (NPHPs). These gene products form protein complexes...
Nephronophthisis (NPH), an autosomal recessive ciliopathy, results from mutations in more than 20 different genes (NPHPs). These gene products form protein complexes that regulate trafficking within the cilium, a microtubular structure that plays a crucial role in developmental processes. Several NPHPs, including NPHP2/Inversin, have been linked to extraciliary functions. In addition to defining a specific segment of primary cilia (Inversin compartment), NPHP2 participates in planar cell polarity (PCP) signaling along with Dishevelled and Vangl family members. We used the mutant zebrafish line invs, containing a stop codon at amino acid 314, to characterize tissue-specific functions of zebrafish Nphp2. The invs line exhibits mild ciliopathy phenotypes and increased glomerular and cloaca cyst formation. These mutants showed enhanced susceptibility to the simultaneous depletion of the nphp1/nphp2/nphp8 module, known to be involved in the cytoskeletal organization of epithelial cells. Notably, simultaneous depletion of zebrafish nphp1 and vangl2 led to a pronounced increase in cloaca malformations in the invs mutant embryos. Time-lapse imaging showed that the pronephric cells correctly migrated towards the ectodermal cells in these embryos, but failed to form the cloaca opening. Despite these abnormal developments, cellular fate does not seem to be affected in nphp1 and vangl2 MO-depleted invs mutants, as shown by in situ hybridizations for markers of pronephros and ectodermal cell development. However, significantly reduced apoptotic activity was observed in this double knockdown model, signifying the role of apoptosis in cloacal morphogenesis. Our findings underscore the critical interplay of nphp1, nphp2/Inversin, and vangl2 in orchestrating normal cloaca formation in zebrafish, shedding light on the complex molecular mechanisms underlying ciliopathy-associated phenotypes.
Topics: Animals; Zebrafish; Cloaca; Cell Polarity; Membrane Proteins; Zebrafish Proteins
PubMed: 37352572
DOI: 10.1016/j.bbrc.2023.06.058 -
Gene Expression Patterns : GEP Dec 2023Peroxidase genes (Prdx) encode a family of antioxidant proteins, which can protect cells from oxidative damage by reducing various cellular peroxides. This study...
Peroxidase genes (Prdx) encode a family of antioxidant proteins, which can protect cells from oxidative damage by reducing various cellular peroxides. This study investigated the spatiotemporal expression patterns of gene members in this family during the early development of Xenopus tropicalis. Real-time quantitative PCR showed that all members of this gene family have a distinct temporal expression pattern during the early development of X. tropicalis embryos. Additionally, whole mount in situ hybridization revealed that individual prdx genes display differential expression patterns, with overlapping expression in lymphatic vessels, pronephros, proximal tubule, and branchial arches. This study provides a basis for further study of the function of the prdx gene family.
Topics: Animals; Xenopus; Xenopus Proteins; Real-Time Polymerase Chain Reaction; Embryonic Development; Gene Expression Regulation, Developmental; Xenopus laevis
PubMed: 37844856
DOI: 10.1016/j.gep.2023.119345 -
Fish & Shellfish Immunology Aug 2023CD27 is a member of the TNF-receptor superfamily and plays various roles in immunities. However, the detailed information and mechanism of CD27 in bony fish immunity...
CD27 is a member of the TNF-receptor superfamily and plays various roles in immunities. However, the detailed information and mechanism of CD27 in bony fish immunity remain unclear. Therefore, in this research, certain interesting roles of CD27 in Nile tilapia (On-CD27) were determined. On-CD27 was largely expressed in the immune organs, head kidney, and spleen, and was sharply induced during bacterial infection. The in vitro tests suggested On-CD27 was involved in regulating inflammatory responses, activating immune-related signal pathways, and inducing apoptosis and pyroptosis progress. The scRNA data and in vivo experiments indicated that On-CD27 is mainly expressed in CD4 T cells and involved in both innate and adaptive immunities. The present data provide a theoretical principle for further research on the mechanisms of CD27 in the innate and adaptive immunities of fish.
Topics: Animals; Cichlids; Fish Proteins; Spleen; Streptococcal Infections; Head Kidney; Fish Diseases; Streptococcus agalactiae; Immunity, Innate; Gene Expression Regulation
PubMed: 37394017
DOI: 10.1016/j.fsi.2023.108923 -
The Science of the Total Environment Jun 2024PFAAs (Perfluoroalkyl acids) are a class of bioaccumulative, persistent and ubiquitous environmental contaminants which primarily occupy the hydrosphere and its...
PFAAs (Perfluoroalkyl acids) are a class of bioaccumulative, persistent and ubiquitous environmental contaminants which primarily occupy the hydrosphere and its sediments. Currently, a paucity of toxicological information exists for short chain PFAAs and complex mixtures. In order to address these knowledge gaps, we performed a 3-week, aqueous exposure of rainbow trout to 3 different concentrations of a PFAA mixture (50, 100 and 500 ng/L) modeled after the composition determined in Lake Ontario. We conducted an additional set of exposures to individual PFAAs (25 nM each of PFOS (12,500 ng/L), PFOA (10,300 ng/L), PFBS (7500 ng/L) or PFBA (5300 ng/L) to evaluate differences in biological response across PFAA congeners. Untargeted proteomics and phosphorylated metabolomics were conducted on the blood plasma and head kidney tissue to evaluate biological response. Plasma proteomic responses to the mixtures revealed several unexpected outcomes including Similar proteomic profiles and biological processes as the PFOS exposure regime while being orders of magnitude lower in concentration and an atypical dose response in terms of the number of significantly altered proteins (FDR < 0.1). Biological pathway analysis revealed the low mixture, medium mixture and PFOS to significantly alter (FDR < 0.05) a number of processes including those involved in lipid metabolism, oxidative stress and the nervous system. We implicate plasma increases in PPARD and PPARG as being directly related to these biological processes as they are known to be important regulators in all 3 processes. In contrast to the blood plasma, the high mixture and PFOA exposure regimes caused the greatest change to the head kidney proteome, altering many proteins being involved in lipid metabolism, oxidative stress and inflammation. Our findings support the pleiotropic effect PFAAs have on aquatic organisms at environmentally relevant doses including those on PPAR signaling, metabolic dysregulation, immunotoxicity and neurotoxicity.
Topics: Animals; Water Pollutants, Chemical; Oncorhynchus mykiss; Fluorocarbons; Proteome; Head Kidney
PubMed: 38615763
DOI: 10.1016/j.scitotenv.2024.172389