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Gerner-Mauro KN, Ellis LV, Wang G, Nayak R, Lwigale PY, Poché RA, Chen J. Morphogenic, molecular, and cellular adaptations for unidirectional airflow in the chicken lung. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.08.20.608866. [PMID: 39229219 PMCID: PMC11370416 DOI: 10.1101/2024.08.20.608866] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/05/2024]
Abstract
Unidirectional airflow in the avian lung enables gas exchange during both inhalation and exhalation. The underlying developmental process and how it deviates from that of the bidirectional mammalian lung are poorly understood. Sampling key developmental stages with multiscale 3D imaging and single-cell transcriptomics, we delineate morphogenic, molecular, and cellular features that accommodate the unidirectional airflow in the chicken lung. Primary termini of hyper-elongated branches are eliminated via proximal-short and distal-long fusions, forming parabronchi. Neoform termini extend radially through parabronchial smooth muscle to form gas-exchanging alveoli. Supporting this radial alveologenesis, branch stalks halt their proximalization, defined by SOX9-SOX2 transition, and become SOX9 low parabronchi. Primary and secondary vascular plexi interface with primary and neoform termini, respectively. Single-cell and Stereo-seq spatial transcriptomics reveal a third, chicken-specific alveolar cell type expressing KRT14, hereby named luminal cells. Luminal, alveolar type 2, and alveolar type 1 cells sequentially occupy concentric zones radiating from the parabronchial lumen. Our study explores the evolutionary space of lung diversification and lays the foundation for functional analysis of species-specific genetic determinants.
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Priede IG, Jamieson AJ, Bond T, Kitazato H. In situ observation of a macrourid fish at 7259 m in the Japan Trench: swimbladder buoyancy at extreme depth. J Exp Biol 2024; 227:jeb246522. [PMID: 38230425 PMCID: PMC10917060 DOI: 10.1242/jeb.246522] [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: 08/07/2023] [Accepted: 01/02/2024] [Indexed: 01/18/2024]
Abstract
A macrourid, Coryphaenoides yaquinae sp. inc., was observed to be attracted to bait and exhibiting normal foraging behaviour during a period of 80 min within view of a baited video camera on the sea floor at 7259 m - the deepest ever observation of a fish species with a swim bladder. The buoyancy provided by an oxygen-filled swim bladder at 74.4 MPa pressure was estimated to be 0.164 N, at a theoretical energy cost of 20 kJ, 200 times less than the cost of equivalent lipid buoyancy. During normal metabolism, 192 days would be required to fill the swimbladder. At these depths, oxygen is very incompressible, so changes in volume during ascent or descent are small. However, swimbladder function is crucially dependent on a very low rate of diffusion of oxygen across the swimbladder wall. The oxygen in the swimbladder could theoretically sustain aerobic metabolism for over 1 year but is unlikely to be used as a reserve.
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Affiliation(s)
- Imants G. Priede
- School of Biological Sciences, University of Aberdeen, Tillydrone Avenue, Aberdeen AB24 2TZ, UK
| | - Alan J. Jamieson
- Minderoo-UWA Deep-Sea Research Centre, School of Biological Sciences and Oceans Institute, The University of Western Australia, 35 Stirling Highway, Perth, WA 6009, Australia
| | - Todd Bond
- Minderoo-UWA Deep-Sea Research Centre, School of Biological Sciences and Oceans Institute, The University of Western Australia, 35 Stirling Highway, Perth, WA 6009, Australia
| | - Hiroshi Kitazato
- Department of Marine Environmental Sciences, Tokyo University of Marine Science and Technology, 4-5-7 Konan, Minato-ku, Tokyo 108-8477, Japan
- Danish Center for Hadal Research, Satellite office at TUMSAT, Tokyo University of Marine Science and Technology, 4-5-7 Konan, Minato-ku, Tokyo 108-8477, Japan
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Chris DI, Wokeh OK, Téllez-Isaías G, Kari ZA, Azra MN. Ecotoxicity of commonly used oilfield-based emulsifiers on Guinean Tilapia ( Tilapia guineensis) using histopathology and behavioral alterations as protocol. Sci Prog 2024; 107:368504241231663. [PMID: 38490166 PMCID: PMC10943731 DOI: 10.1177/00368504241231663] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/17/2024]
Abstract
This study examined the histological aberrations in the gill and liver tissues and behavioural changes of Tilapia guineensis fingerlings exposed to lethal concentrations of used Oilfield-based emulsifiers for 96 h. Various concentrations of the surfactants were tested, ranging from 0.0 to 15.0 ml/L. The behaviour of the fish was observed throughout the experiment, and the results showed that increasing concentrations of the surfactants led to progressively abnormal behaviour, including hyperventilation and altered opercular beat frequency. These behavioural changes indicated respiratory distress and neurotoxic effects. Histological analysis revealed structural aberrations in the gill and liver tissues, with higher concentrations causing more severe damage, such as lesions, necrosis, inflammation, and cellular degeneration. This implies that surfactants released even at low concentrations are capable of inducing changes in the tissues of aquatic organisms. These findings highlight the toxic effects of the surfactants on fish health and provide biomarkers of toxicity. Future research should focus on understanding the specific mechanisms and long-term consequences of surfactant toxicity on fish genetic composition, populations, and ecosystems to implement effective conservation measures.
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Affiliation(s)
- Davies Ibienebo Chris
- World Bank Africa Centre of Excellence, Centre for Oilfield Chemicals Research, University of Port Harcourt, Choba, Rivers State, Nigeria
- Department of Fisheries, University of Port Harcourt, Choba, Rivers State, Nigeria
| | - Okechukwu Kenneth Wokeh
- Department of Animal and Environmental Biology, University of Port Harcourt, Choba, Rivers State, Nigeria
| | | | - Zulhisyam Abdul Kari
- Department of Agricultural Science, Faculty of Agro-Based Industry, Universiti Malaysia Kelantan, Jeli, Kelantan, Malaysia
| | - Mohamad Nor Azra
- Institute of Climate Adaptation and Marine Biotechnology (ICAMB), Universiti Malaysia Terengganu (UMT), Kuala Nerus, Terengganu, Malaysia
- Research Center for Marine and Land Bioindustry (Earth Sciences and Maritime), National Research and Innovation Agency (BRIN), Pemenang, West Nusa Tenggara, Indonesia
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Zhang R, Liu Q, Pan S, Zhang Y, Qin Y, Du X, Yuan Z, Lu Y, Song Y, Zhang M, Zhang N, Ma J, Zhang Z, Jia X, Wang K, He S, Liu S, Ni M, Liu X, Xu X, Yang H, Wang J, Seim I, Fan G. A single-cell atlas of West African lungfish respiratory system reveals evolutionary adaptations to terrestrialization. Nat Commun 2023; 14:5630. [PMID: 37699889 PMCID: PMC10497629 DOI: 10.1038/s41467-023-41309-3] [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: 12/01/2022] [Accepted: 08/30/2023] [Indexed: 09/14/2023] Open
Abstract
The six species of lungfish possess both lungs and gills and are the closest extant relatives of tetrapods. Here, we report a single-cell transcriptome atlas of the West African lungfish (Protopterus annectens). This species manifests the most extreme form of terrestrialization, a life history strategy to survive dry periods that can last for years, characterized by dormancy and reversible adaptive changes of the gills and lungs. Our atlas highlights the cell type diversity of the West African lungfish, including gene expression consistent with phenotype changes of terrestrialization. Comparison with terrestrial tetrapods and ray-finned fishes reveals broad homology between the swim bladder and lung cell types as well as shared and idiosyncratic changes of the external gills of the West African lungfish and the internal gills of Atlantic salmon. The single-cell atlas presented here provides a valuable resource for further exploration of the respiratory system evolution in vertebrates and the diversity of lungfish terrestrialization.
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Affiliation(s)
- Ruihua Zhang
- College of Life Sciences, University of Chinese Academy of Sciences, 100049, Beijing, China
- BGI Research, 266555, Qingdao, China
- Qingdao Key Laboratory of Marine Genomics, BGI Research, 266555, Qingdao, China
| | - Qun Liu
- BGI Research, 266555, Qingdao, China
- Qingdao Key Laboratory of Marine Genomics, BGI Research, 266555, Qingdao, China
- Department of Biology, University of Copenhagen, Copenhagen, 2100, Denmark
| | - Shanshan Pan
- BGI Research, 266555, Qingdao, China
- Qingdao Key Laboratory of Marine Genomics, BGI Research, 266555, Qingdao, China
| | - Yingying Zhang
- BGI Research, 266555, Qingdao, China
- Qingdao Key Laboratory of Marine Genomics, BGI Research, 266555, Qingdao, China
| | - Yating Qin
- BGI Research, 266555, Qingdao, China
- Qingdao Key Laboratory of Marine Genomics, BGI Research, 266555, Qingdao, China
| | - Xiao Du
- BGI Research, 266555, Qingdao, China
- Qingdao Key Laboratory of Marine Genomics, BGI Research, 266555, Qingdao, China
- BGI Research, 518083, Shenzhen, China
| | - Zengbao Yuan
- College of Life Sciences, University of Chinese Academy of Sciences, 100049, Beijing, China
- BGI Research, 266555, Qingdao, China
- Qingdao Key Laboratory of Marine Genomics, BGI Research, 266555, Qingdao, China
| | - Yongrui Lu
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, 430072, Wuhan, China
| | - Yue Song
- BGI Research, 266555, Qingdao, China
- Qingdao Key Laboratory of Marine Genomics, BGI Research, 266555, Qingdao, China
| | | | - Nannan Zhang
- BGI Research, 266555, Qingdao, China
- Qingdao Key Laboratory of Marine Genomics, BGI Research, 266555, Qingdao, China
| | - Jie Ma
- BGI Research, 266555, Qingdao, China
- Qingdao Key Laboratory of Marine Genomics, BGI Research, 266555, Qingdao, China
| | | | - Xiaodong Jia
- Joint Laboratory for Translational Medicine Research, Liaocheng People's Hospital, 252000, Liaocheng, Shandong, P.R. China
| | - Kun Wang
- Center for Ecological and Environmental Sciences, Northwestern Polytechnical University, 710072, Xi'an, China
| | - Shunping He
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, 430072, Wuhan, China
| | - Shanshan Liu
- BGI Research, 518083, Shenzhen, China
- MGI Tech, 518083, Shenzhen, China
| | - Ming Ni
- BGI Research, 518083, Shenzhen, China
- MGI Tech, 518083, Shenzhen, China
| | - Xin Liu
- BGI Research, 518083, Shenzhen, China
| | - Xun Xu
- BGI Research, 518083, Shenzhen, China
- Guangdong Provincial Key Laboratory of Genome Read and Write, BGI Research, 518083, Shenzhen, China
| | | | - Jian Wang
- BGI Research, 518083, Shenzhen, China
| | - Inge Seim
- Integrative Biology Laboratory, College of Life Sciences, Nanjing Normal University, Nanjing, China.
- School of Biology and Environmental Science, Queensland University of Technology, Brisbane, 4000, Australia.
| | - Guangyi Fan
- BGI Research, 266555, Qingdao, China.
- Qingdao Key Laboratory of Marine Genomics, BGI Research, 266555, Qingdao, China.
- BGI Research, 518083, Shenzhen, China.
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Melo BF, de Pinna MCC, Rapp Py-Daniel LH, Zuanon J, Conde-Saldaña CC, Roxo FF, Oliveira C. Paleogene emergence and evolutionary history of the Amazonian fossorial fish genus Tarumania (Teleostei: Tarumaniidae). Front Ecol Evol 2022. [DOI: 10.3389/fevo.2022.924860] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Tarumania walkerae is a rare fossorial freshwater fish species from the lower Rio Negro, Central Amazonia, composing the monotypic and recently described family Tarumaniidae. The family has been proposed as the sister group of Erythrinidae by both morphological and molecular studies despite distinct arrangements of the superfamily Erythrinoidea within Characiformes. Recent phylogenomic studies and time-calibrated analyses of characoid fishes have not included specimens of Tarumania in their analyses. We obtained genomic data for T. walkerae and constructed a phylogeny based on 1795 nuclear loci with 488,434 characters of ultraconserved elements (UCEs) for 108 terminals including specimens of all 22 characiform families. The phylogeny confirms the placement of Tarumaniidae as sister to Erythrinidae but differs from the morphological hypothesis in the placement of the two latter families as sister to the clade with Hemiodontidae, Cynodontidae, Serrasalmidae, Parodontidae, Anostomidae, Prochilodontidae, Chilodontidae, and Curimatidae. The phylogeny calibrated with five characoid fossils indicates that Erythrinoidea diverged from their relatives during the Late Cretaceous circa 90 Ma (108–72 Ma), and that Tarumania diverged from the most recent common ancestor of Erythrinidae during the Paleogene circa 48 Ma (66–32 Ma). The occurrence of the erythrinoid-like †Tiupampichthys in the Late Cretaceous–Paleogene formations of the El Molino Basin of Bolivia supports our hypothesis for the emergence of the modern Erythrinidae and Tarumaniidae during the Paleogene.
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Euclide PT, Jasonowicz A, Sitar S, Fischer G, Goetz FW. Further evidence from common garden rearing experiments of heritable traits separating lean and siscowet lake charr (Salvelinus namaycush) ecotypes. Mol Ecol 2022; 31:3432-3450. [PMID: 35510796 PMCID: PMC9323484 DOI: 10.1111/mec.16492] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2021] [Revised: 03/07/2022] [Accepted: 04/12/2022] [Indexed: 11/30/2022]
Abstract
Genetic evidence of selection for complex and polygenically regulated phenotypes can easily become masked by neutral population genetic structure and phenotypic plasticity. Without direct evidence of genotype‐phenotype associations it can be difficult to conclude to what degree a phenotype is heritable or a product of environment. Common garden laboratory studies control for environmental stochasticity and help to determine the mechanism that regulate traits. Here we assess lipid content, growth, weight, and length variation in full and hybrid F1 crosses of deep and shallow water sympatric lake charr ecotypes reared for nine years in a common garden experiment. Redundancy analysis (RDA) and quantitative‐trait‐loci (QTL) genomic scans are used to identify associations between genotypes at 19,714 single nucleotide polymorphisms (SNPs) aligned to the lake charr genome and individual phenotypes to determine the role that genetic inheritance plays in ecotype phenotypic diversity. Lipid content, growth, length, and weight differed significantly among lake charr crosses throughout the experiment suggesting that pedigree plays a large roll in lake charr development. Polygenic scores of 15 SNPs putatively associated with lipid content and/or condition factor indicated that ecotype distinguishing traits are polygenically regulated and additive. A QTL identified on chromosome 38 contained >200 genes, some of which were associated with lipid metabolism and growth, demonstrating the complex nature of ecotype diversity. The results of our common garden study further indicate that lake charr ecotypes observed in nature are predetermined at birth and that ecotypes differ fundamentally in lipid metabolism and growth.
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Affiliation(s)
- P T Euclide
- Purdue University, Department of Forestry and Natural Resources, West Lafayette, IN, 47907, USA
| | - A Jasonowicz
- The International Halibut Commission, 2320 West Commodore Way, Suite 300, Seattle, WA, 98199-1287, USA
| | - S Sitar
- Michigan Department of Natural Resources, Marquette Fisheries Research Station, 484 Cherry Creek Rd., Marquette, MI, 49855, USA
| | - G Fischer
- University of Wisconsin-Stevens Point, Northern Aquaculture Demonstration Facility, 36445 State Hwy 13, Bayfield, WI, 54814, USA
| | - F W Goetz
- University of Wisconsin - Milwaukee, School of Freshwater Sciences, 600 East Greenfield Ave., Milwaukee, WI, 53204, USA
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Oxygen consumption and acid secretion in isolated gas gland cells of the European eel Anguilla anguilla. J Comp Physiol B 2022; 192:447-457. [PMID: 35289381 PMCID: PMC9197889 DOI: 10.1007/s00360-022-01432-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2021] [Revised: 02/18/2022] [Accepted: 02/23/2022] [Indexed: 02/06/2023]
Abstract
Swimbladder gas gland cells are known to produce lactic acid required for the acidification of swimbladder blood and decreasing the oxygen carrying capacity of swimbladder blood, i.e., the onset of the Root effect. Gas gland cells have also been shown to metabolize glucose via the pentose phosphate shunt, but the role of the pentose phosphate shunt for acid secretion has not yet been evaluated. Similarly, aerobic metabolism of gas gland cells has been largely neglected so far. In the present study, we therefore simultaneously assessed the role of glycolysis and of the pentose phosphate shunt for acid secretion and recorded oxygen consumption of isolated swimbladder gas gland cells of the European eel. Presence of glucose was essential for acid secretion, and at glucose concentrations of about 1.5 mmol l−1 acid secretion of gas gland cells reached a maximum, indicating that glucose concentrations in swimbladder blood should not be limiting acid production and secretion under physiological conditions. The data revealed that most of the acid was produced in the glycolytic pathway, but a significant fraction was also contributed by the pentose phosphate shunt. Addition of glucose to gas gland cells incubated in a glucose-free medium resulted in a reduction of oxygen uptake. Inhibition of mitochondrial respiration significantly reduced oxygen consumption, but a fraction of mitochondria-independent respiration remained in presence of rotenone and antimycin A. In the presence of glucose, application of either iodo-acetate inhibiting glycolysis or 6-AN inhibiting the pentose phosphate shunt did not significantly affect oxygen uptake, indicating an independent regulation of oxidative phosphorylation and of acid production. Inhibition of the muscarinic acetylcholine receptor caused a slight elevation in acid secretion, while forskolin caused a concentration-dependent reduction in acid secretion, indicating muscarinic and c-AMP-dependent control of acid secretion in gas gland cells.
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Drechsel V, Schneebauer G, Fiechtner B, Cutler CP, Pelster B. Aquaporin expression and cholesterol content in eel swimbladder tissue. JOURNAL OF FISH BIOLOGY 2022; 100:609-618. [PMID: 34882794 PMCID: PMC9302985 DOI: 10.1111/jfb.14973] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2021] [Revised: 12/01/2021] [Accepted: 12/02/2021] [Indexed: 05/08/2023]
Abstract
Leakiness of the swimbladder wall of teleost fishes must be prevented to avoid diffusional loss of gases out of the swimbladder. Guanine incrustation as well as high concentrations of cholesterol in swimbladder membranes in midwater and deep-sea fish has been connected to a reduced gas permeability of the swimbladder wall. On the contrary, the swimbladder is filled by diffusion of gases, mainly oxygen and CO2 , from the blood and the gas gland cells into the swimbladder lumen. In swimbladder tissue of the zebrafish and the Japanese eel, aquaporin mRNA has been detected, and the aquaporin protein has been considered important for the diffusion of water, which may accidentally be gulped by physostome fish when taking an air breath. In the present study, the expression of two aquaporin 1 genes (Aqp1aa and Aqp1ab) in the swimbladder tissue of the European eel, a functional physoclist fish, was assessed using immunohistochemistry, and the expression of both genes was detected in endothelial cells of swimbladder capillaries as well as in basolateral membranes of gas gland cells. In addition, Aqp1ab was present in apical membranes of swimbladder gas gland cells. The authors also found high concentrations of cholesterol in these membranes, which were several fold higher than in muscle tissue membranes. In yellow eels the cholesterol concentration exceeded the concentration detected in silver eel swimbladder membranes. The authors suggest that aquaporin 1 in swimbladder gas gland cells and endothelial cells facilitates CO2 diffusion into the blood, enhancing the switch-on of the Root effect, which is essential for the secretion of oxygen into the swimbladder. It may also facilitate CO2 diffusion into the swimbladder lumen along the partial gradient established by CO2 production in gas gland cells. Cholesterol has been shown to reduce the gas permeability of membranes and thus could contribute to the gas tightness of swimbladder membranes, which is essential to avoid diffusional loss of gas out of the swimbladder.
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Affiliation(s)
- Victoria Drechsel
- Institute of ZoologyUniversity of InnsbruckInnsbruckAustria
- Center for Molecular BiosciencesUniversity of InnsbruckInnsbruckAustria
| | - Gabriel Schneebauer
- Institute of ZoologyUniversity of InnsbruckInnsbruckAustria
- Center for Molecular BiosciencesUniversity of InnsbruckInnsbruckAustria
| | - Birgit Fiechtner
- Institute of ZoologyUniversity of InnsbruckInnsbruckAustria
- Center for Molecular BiosciencesUniversity of InnsbruckInnsbruckAustria
| | | | - Bernd Pelster
- Institute of ZoologyUniversity of InnsbruckInnsbruckAustria
- Center for Molecular BiosciencesUniversity of InnsbruckInnsbruckAustria
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Schneebauer G, Drechsel V, Dirks R, Faserl K, Sarg B, Pelster B. Expression of transport proteins in the rete mirabile of european silver and yellow eel. BMC Genomics 2021; 22:866. [PMID: 34856920 PMCID: PMC8638102 DOI: 10.1186/s12864-021-08180-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2021] [Accepted: 11/16/2021] [Indexed: 12/03/2022] Open
Abstract
BACKGROUND In physoclist fishes filling of the swimbladder requires acid secretion of gas gland cells to switch on the Root effect and subsequent countercurrent concentration of the initial gas partial pressure increase by back-diffusion of gas molecules in the rete mirabile. It is generally assumed that the rete mirabile functions as a passive exchanger, but a detailed analysis of lactate and water movements in the rete mirabile of the eel revealed that lactate is diffusing back in the rete. In the present study we therefore test the hypothesis that expression of transport proteins in rete capillaries allows for back-diffusion of ions and metabolites, which would support the countercurrent concentrating capacity of the rete mirabile. It is also assumed that in silver eels, the migratory stage of the eel, the expression of transport proteins would be enhanced. RESULTS Analysis of the transcriptome and of the proteome of rete mirabile tissue of the European eel revealed the expression of a large number of membrane ion and metabolite transport proteins, including monocarboxylate and glucose transport proteins. In addition, ion channel proteins, Ca2+-ATPase, Na+/K+-ATPase and also F1F0-ATP synthase were detected. In contrast to our expectation in silver eels the expression of these transport proteins was not elevated as compared to yellow eels. A remarkable number of enzymes degrading reactive oxygen species (ROS) was detected in rete capillaries. CONCLUSIONS Our results reveal the expression of a large number of transport proteins in rete capillaries, so that the back diffusion of ions and metabolites, in particular lactate, may significantly enhance the countercurrent concentrating ability of the rete. Metabolic pathways allowing for aerobic generation of ATP supporting secondary active transport mechanisms are established. Rete tissue appears to be equipped with a high ROS defense capacity, preventing damage of the tissue due to the high oxygen partial pressures generated in the countercurrent system.
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Affiliation(s)
- Gabriel Schneebauer
- Institute of Zoology, University of Innsbruck, Innsbruck, Austria
- Center for Molecular Biosciences, University Innsbruck, Innsbruck, Austria
| | - Victoria Drechsel
- Institute of Zoology, University of Innsbruck, Innsbruck, Austria
- Center for Molecular Biosciences, University Innsbruck, Innsbruck, Austria
| | - Ron Dirks
- Future Genomics Technologies, Leiden, The Netherlands
| | - Klaus Faserl
- Institute of Medical Biochemistry, Protein Core Facility, Medical University Innsbruck, Innsbruck, Austria
| | - Bettina Sarg
- Institute of Medical Biochemistry, Protein Core Facility, Medical University Innsbruck, Innsbruck, Austria
| | - Bernd Pelster
- Institute of Zoology, University of Innsbruck, Innsbruck, Austria.
- Center for Molecular Biosciences, University Innsbruck, Innsbruck, Austria.
- Institut für Zoologie Leopold-Franzens-Universität Innsbruck, Technikerstr. 25, A-6020, Innsbruck, Austria.
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