A novel and ancient group of type I keratins with members in bichir, sturgeon and gar

<p>Abstract</p> <p>1. Background</p> <p>Vertebrate epithelial cells typically express a specific set of keratins. In teleosts, keratins are also present in a variety of mesenchymal cells, which usually express vimentin. Significantly, our previous studies revealed that virtually all known teleost keratins evolved independently from those present in terrestrial vertebrates. To further elucidate the evolutionary scenario that led to the large variety of keratins and their complex expression patterns in present day teleosts, we have investigated their presence in bichir, sturgeon and gar.</p> <p>2. Results</p> <p>We have discovered a novel group of type I keratins with members in all three of these ancient ray-finned fish, but apparently no counterparts are present in any other vertebrate class so far investigated, including the modern teleost fish. From sturgeon and gar we sequenced one and from bichir two members of this novel keratin group. By complementary keratin blot-binding assays and peptide mass fingerprinting using MALDI-TOF mass spectrometry, in sturgeon we were able to assign the sequence to a prominent protein spot, present exclusively in a two-dimensionally separated cytoskeletal preparation of skin, thus identifying it as an epidermally expressed type I keratin. In contrast to the other keratins we have so far sequenced from bichir, sturgeon and gar, these new sequences occupy a rather basal position within the phylogenetic tree of type I keratins, in a close vicinity to the keratins we previously cloned from river lamprey.</p> <p>3. Conclusion</p> <p>Thus, this new K14 group seem to belong to a very ancient keratin branch, whose functional role has still to be further elucidated. Furthermore, the exclusive presence of this keratin group in bichir, sturgeon and gar points to the close phylogenetic relationship of these ray- finned fish, an issue still under debate among taxonomists.</p

Time and tide : seasonal, diel and tidal rhythms in Wadden Sea Harbour porpoises (Phocoena phocoena)

The study was partly funded by the Schleswig-Holstein’s Government-Owned Company for Coastal Protection, National Parks and Ocean Protection, Wadden Sea National Park Administration of Lower Saxony (Richard Czeck) and the German Federal Ministry for the Environment, Nature Conservation and Nuclear Safety (FKZ: 03 275 20 and FKZ: 0329946B). This publication was supported by Deutsche Forschungsgemeinschaft and University of Veterinary Medicine Hannover, Foundation within the funding programme Open Access Publishing.Odontocetes have evolved a rich diversity of prey- and habitat-specific foraging strategies, which allows them to feed opportunistically on locally and temporally abundant prey. While habitat-specific foraging strategies have been documented for some odontocete species, this is less known for the harbour porpoise (Phocoena phocoena). We collected multiple years of acoustic data using echolocation click loggers to analyse porpoise occurrence and buzzing behaviour, indicating feeding, in the German Wadden Sea (North Sea). Seasonal, diel and tidal effects were studied using Generalised Estimating Equations (GEE-GAMs). Locally season, time of day and tidal time significantly influenced the probability of porpoise detections and detection of foraging sequences (buzzes). Hunting strategies, and therefore frequency of buzzes, were likely affected by prey distribution and large differences between POD locations indicated that porpoises used highly specific behaviour adapted to tide and time of day to efficiently feed on the available prey. Strong seasonal and spatial variation in diel and tidal effects underline the importance of long-term observations. Studies on porpoise behaviour are often based on short-term observations and might rather reflect a seasonal than a general pattern. The results of this study show clearly that significant changes in porpoise behaviour can be found in short and long-term observations. Here some features are based on short term determinants and others are stable over years and care should be taken about drawing general conclusions based on local patterns. Highly variable spatio-temporal patterns indicate a high flexibility of porpoises in a highly variable environment and address a challenge for complex conservation management plans.Publisher PDFPeer reviewe

A novel and ancient group of type I keratins with members in bichir, sturgeon and gar-0

<p><b>Copyright information:</b></p><p>Taken from "A novel and ancient group of type I keratins with members in bichir, sturgeon and gar"</p><p>http://www.frontiersinzoology.com/content/4/1/16</p><p>Frontiers in Zoology 2007;4():16-16.</p><p>Published online 6 Jun 2007</p><p>PMCID:PMC1896152.</p><p></p> and gar. Thick black lines mark the four helical subdomains (coils 1A to 2B), which are typical for the central rod domain of all known IF-proteins. Asterisks indicate identical amino acids; double dots indicate a high and single dots a lower degree of amino acid conservation. Pse, (bichir); Aba, (sturgeon); Loc, (gar). Note that only AbaK14 comprises the complete amino acid sequence. From PseK14a at least a section and from LocK14 the complete head sequence is still missing. From PseK14b we still have to recover both, the complete head and tail sequence

A novel and ancient group of type I keratins with members in bichir, sturgeon and gar-4

<p><b>Copyright information:</b></p><p>Taken from "A novel and ancient group of type I keratins with members in bichir, sturgeon and gar"</p><p>http://www.frontiersinzoology.com/content/4/1/16</p><p>Frontiers in Zoology 2007;4():16-16.</p><p>Published online 6 Jun 2007</p><p>PMCID:PMC1896152.</p><p></p> and gar. Thick black lines mark the four helical subdomains (coils 1A to 2B), which are typical for the central rod domain of all known IF-proteins. Asterisks indicate identical amino acids; double dots indicate a high and single dots a lower degree of amino acid conservation. Pse, (bichir); Aba, (sturgeon); Loc, (gar). Note that only AbaK14 comprises the complete amino acid sequence. From PseK14a at least a section and from LocK14 the complete head sequence is still missing. From PseK14b we still have to recover both, the complete head and tail sequence

A novel and ancient group of type I keratins with members in bichir, sturgeon and gar-2

<p><b>Copyright information:</b></p><p>Taken from "A novel and ancient group of type I keratins with members in bichir, sturgeon and gar"</p><p>http://www.frontiersinzoology.com/content/4/1/16</p><p>Frontiers in Zoology 2007;4():16-16.</p><p>Published online 6 Jun 2007</p><p>PMCID:PMC1896152.</p><p></p>nce. *For three type I keratin sequences the Ensembl database gene IDs are given

A novel and ancient group of type I keratins with members in bichir, sturgeon and gar-3

<p><b>Copyright information:</b></p><p>Taken from "A novel and ancient group of type I keratins with members in bichir, sturgeon and gar"</p><p>http://www.frontiersinzoology.com/content/4/1/16</p><p>Frontiers in Zoology 2007;4():16-16.</p><p>Published online 6 Jun 2007</p><p>PMCID:PMC1896152.</p><p></p>14 sequences from bichir, sturgeon and gar to the other type I keratins known from vertebrates. The tree was rooted with the lancelet type I keratin sequences. It clearly shows that the K14 sequences form a separate branch (boxed in violet) close to the sequences we cloned from the river lamprey. They even branch off prior to the twig formed by the gnathostomian K18 sequences (boxed in green) that apparently emerged before the separation of cartilaginous and bony fish. The tree, furthermore, suggests that most of the ray-finned fish type I keratins (boxed in blue) evolved independently from those present in lungfish, frog or man and that early in actinopterygian evolution gene duplications already gave rise to at least two different type I keratin groups with members in both, ancient and modern ray-finned fish. Importantly, within the tetrapod lineage the Bayesian analysis revealed four highly supported keratin subgroups, each with members in both, frog and man (encircled by dotted lines and coloured orange). Bar, 0.1 substitutions per site

Time and tide:seasonal, diel and tidal rhythms in Wadden Sea Harbour porpoises (<i>Phocoena phocoena</i>)

Odontocetes have evolved a rich diversity of prey- and habitat-specific foraging strategies, which allows them to feed opportunistically on locally and temporally abundant prey. While habitat-specific foraging strategies have been documented for some odontocete species, this is less known for the harbour porpoise (Phocoena phocoena). We collected multiple years of acoustic data using echolocation click loggers to analyse porpoise occurrence and buzzing behaviour, indicating feeding, in the German Wadden Sea (North Sea). Seasonal, diel and tidal effects were studied using Generalised Estimating Equations (GEE-GAMs). Locally season, time of day and tidal time significantly influenced the probability of porpoise detections and detection of foraging sequences (buzzes). Hunting strategies, and therefore frequency of buzzes, were likely affected by prey distribution and large differences between POD locations indicated that porpoises used highly specific behaviour adapted to tide and time of day to efficiently feed on the available prey. Strong seasonal and spatial variation in diel and tidal effects underline the importance of long-term observations. Studies on porpoise behaviour are often based on short-term observations and might rather reflect a seasonal than a general pattern. The results of this study show clearly that significant changes in porpoise behaviour can be found in short and long-term observations. Here some features are based on short term determinants and others are stable over years and care should be taken about drawing general conclusions based on local patterns. Highly variable spatio-temporal patterns indicate a high flexibility of porpoises in a highly variable environment and address a challenge for complex conservation management plans

Following the adverse outcome pathway from micronucleus to cancer using H2B-eGFP transgenic healthy stem cells

In vitro assessment of genotoxicity as an early warning tool for carcinogenicity mainly relies on recording cytogenetic damages (micronuclei, nucleoplasmic bridges) in tumour-derived mammalian cell lines like V79 or CHO. The forecasting power of the corresponding standardised test is based on epidemiological evidence between micronuclei frequencies and cancer incidence. As an alternative to destructive staining of nuclear structures a fish stem cell line transgenic for a fusion protein of histone 2B (H2B) and enhanced green fluorescent protein (eGFP) was established. The cells are derived from koi carp brain (KCB) and distinguish from mammalian culturable cells by non-tumour-driven self-renewal. This technology enables the analysis of genotoxic- and malign downstream effects in situ in a combined approach. In proof-of concept-experiments, we used known carcinogens (4-Nitroquinoline 1-oxide, colchicine, diethylstilbestrol, ethyl methanesulfonate) and observed a significant increase in micronuclei (MNi) frequencies in a dose-dependent manner. The concentration ranges for MNi induction were comparable to human/mammalian cells (i.e. VH-16, CHL and HepG2). Cannabidiol caused the same specific cytogenetic damage pattern as observed in human cells, in particular nucleoplasmic bridges. Metabolic activation of aflatoxin B1 and cyclophosphamide could be demonstrated by pre-incubation of the test compounds using either conventional rat derived S9 mix as well as an in vitro generated biotechnological alternative product ewoS9R. The presented high throughput live H2B-eGFP imaging technology using non-transformed stem cells opens new perspectives in the field of in vitro toxicology. The technology offers experimental access to investigate the effects of carcinogens on cell cycle control, gene expression pattern and motility in the course of malign transformation. The new technology enables the definition of Adverse Outcome Pathways leading to malign cell transformation and contributes to the replacement of animal testing. Summary: Complementation of genotoxicity testing by addressing initiating events leading to malign transformation is suggested. A vertebrate cell model showing healthy stemness is recommended, in contrast to malign transformed cells used in toxicology/oncocology