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Rainer Keller - One of the best experts on this subject based on the ideXlab platform.
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Identification of Neuropeptides from the Sinus Gland of the Crayfish Orconectes Limosus Using Nanoscale On-line Liquid Chromatography Tandem Mass Spectrometry
Molecular & cellular proteomics : MCP, 2004Co-Authors: Patrick Bulau, Rainer Keller, Iris Meisen, Tina Schmitz, Jasna Peter-katalinićAbstract:In this article, a novel and sensitive analytical strategy for direct characterization of neuropeptides from the X-Organ-sinus gland neurosecretory system of the crayfish Orconectes Limosus is presented. A desalted extract corresponding to 0.5 sinus gland equivalents was analyzed in a nanoflow liquid chromatography system coupled to quadrupole time-of-flight tandem mass spectrometry (nanoLC-QTOF MS/MS). The existence and structural identity of four crustacean hyperglycemic hormone precursor-related peptide variants and two new genetic variants of the pigment-dispersing hormone, not detected by conventional chromatographic systems, molecular cloning, or immunochemical methods before, was revealed. The here-presented approach of the combined LC-QTOF MS/MS technique is a powerful tool to discover new peptide hormones in biological systems, due to its sensitivity, accuracy, and speed.
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Structure and localization of mRNA encoding a pigment dispersing hormone (PDH) in the eyestalk of the crayfish Orconectes Limosus
FEBS Letters, 1993Co-Authors: Dominique P.v. De Kleijn, Rainer Keller, Birgit Linck, J.m. Klein, Wolfgang M. Weidemann, François Van HerpAbstract:The pigment-dispersing hormone (PDH) is produced in the eyestalks of Crustacea where it induces light-adapting movements of pigment in the compound eye and regulates the pigment dispersion in the chromatophores. To study this hormone at the mRNA level, we cloned and sequenced cDNA encoding PDH in the crayfish Orconectes Limosus. The structure of the PDH preprohormone consists of a signal peptide, a PDH precursor-related peptide (PPRP) and the highly conserved PDH peptide at the carboxy-terminal end. In situ hybridization in combination with immunocytochemistry revealed four cell clusters expressing PDH in the optic ganglia of the eyestalk. Three clusters stained both with the PDH cRNA probe and the PDH antiserum, however, the perikarya in the lamina ganglionaris (LG) only stained with the PDH antiserum, suggesting the presence of a PDH-like peptide in the LG.
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High-affinity binding of crustacean hyperglycemic hormone (CHH) to hepatopancreatic plasma membranes of the crab Carcinus maenas and the crayfish Orconectes Limosus
Peptides, 1993Co-Authors: Gerhard Kummer, Rainer KellerAbstract:Abstract The binding properties of the crustacean hyperglycemic hormone (CHH) of two species, the shore crab, Carcinus maenas (Brachyura) and the crayfish, Orconectes Limosus (Astacura), were investigated using purified plasma membranes of one of the main target organs, the hepatopancreas. Assays were performed under equilibrium binding conditions with 125I-CHH as labeled ligand and unlabeled CHH in increasing concentrations as displacing ligand. In both cases, comparable binding characteristics were observed for the homologous CHH to the respective hepatopancreatic membrane source, indicating saturable and displaceable binding with nonlinear dependence on monovalent cations and a dissociation constant ( K d ) of 4 to 6 × 10 −10 M . Binding capacity was in the range of 200–400 fmol/mg membrane protein. In heterologous displacement studies a certain degree of species specificity was found, particularly with regard to selective binding by the Orconectes receptor, suggesting that the group specificity of biological activity of CHH reflects coevolution of both hormone and receptor.
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Orcokinin: a novel myotropic peptide from the nervous system of the crayfish, Orconectes Limosus.
Peptides, 1992Co-Authors: J. Stangier, Caroline Hilbich, Siegward Burdzik, Rainer KellerAbstract:Abstract A myotropic peptide, named orcokinin, was isolated from approximately 1200 abdominal nerve cords of the crayfish, Orconectes Limosus . Its amino acid sequence was determined as follows: Asn-Phe-Asp-Glu-Ile-Asp-Arg-Ser-Gly-Phe-Gly-Phe-Asn. This structure was confirmed by synthesis. There is no sequence similarity to any known neuropeptide. Orcokinin exhibits high potency on the crayfish hindgut, enhancing both frequency and amplitude of spontaneous contractions. The threshold of biological activity in vitro was determined to be approximately 5 × 10 −11 M .
Adam Petrusek - One of the best experts on this subject based on the ideXlab platform.
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Spiny-cheek crayfish Orconectes Limosus carry a novel genotype of the crayfish plague pathogen Aphanomyces astaci
Journal of invertebrate pathology, 2011Co-Authors: E. Kozubíková, Satu Viljamaa-dirks, Sirpa Heinikainen, Adam PetrusekAbstract:The oomycete Aphanomyces astaci causes mass mortalities of European crayfish. Different species of North American crayfish, original hosts of this parasite, seem to carry different strains of A. astaci. So far, four distinct genotype groups have been recognised using Random Amplification of Polymorphic DNA (RAPD-PCR). We succeeded in isolating A. astaci from the spiny-cheek crayfish Orconectes Limosus, a widespread invader in Europe, and confirmed that this species carries a novel A. astaci genotype. Improving knowledge on the diversity of this parasite may facilitate identification of genotypes in mass mortalities of European crayfish, thus tracing the sources of infection.
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Haplotype variation in the spiny-cheek crayfish Orconectes Limosus: colonization of Europe and genetic diversity of native stocks
Journal of the North American Benthological Society, 2011Co-Authors: Lenka Filipová, Frederic Grandjean, David A. Lieb, Adam PetrusekAbstract:AbstractThe North American spiny-cheek crayfish, Orconectes Limosus (Rafinesque, 1817), a widespread invader in Europe, seems to have been introduced there successfully only once. According to available literature, 90 individuals of unclear origin were released in Poland in 1890. Despite this apparent bottleneck, the species has successfully colonized various aquatic habitats and has displaced native crayfish species in many places. To test whether different European populations were likely to have come from a single source and to identify their possible origin, we analyzed the diversity of the mitochondrial gene for cytochrome c oxidase subunit I (COI) of O. Limosus individuals from Europe and from its original range in North America, including the presumed source region of European populations, the Delaware River watershed (eastern USA). Two haplotypes were found in European populations. One haplotype was widespread; the other was present in a single population. In contrast, 18 haplotypes were detected ...
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Cross-species amplification of microsatellite markers in the invasive spiny-cheek crayfish [Orconectes Limosus]: assessment and application
Journal of applied genetics, 2010Co-Authors: Martin Hulak, Lenka Filipová, Pavel Kozak, V. Kašpar, M. Buřià, Adam PetrusekAbstract:The North American spiny-cheek crayfish,Orconectes Limosus (Cambaridae), endangered in its native range, is a widespread invasive species in European waters and conservationally important carrier of crayfish plague. However, its population structure is poorly known, and no informative genetic markers for the species are available. We tested cross-species transfer of microsatellite loci to spiny-cheek crayfish from 5 other crayfish species. Variability of 10 successfully amplifying loci derived from 4 species was then tested in 60 individuals ofO. Limosus originating from 3 natural populations: the river Danube at Bogyiszlo in Hungary, a pond in Starý Klicov, and the brook Cernovický, both in the Czech Republic. The allele number within the populations ranged from 4 to 10 alleles per locus, while heterozygosity levels varied from 0.650 to 0.900 forHo and from 0.660 to 0.890 forHe. No linkage disequilibrium and no null alleles were detected. The selected markers are useful for assessing population structure, intraspecific variation, and paternity studies in spiny-cheek crayfish.
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allozyme variation in czech populations of the invasive spiny cheek crayfish Orconectes Limosus cambaridae
Knowledge and Management of Aquatic Ecosystems, 2009Co-Authors: Lenka Filipová, E. Kozubíková, Adam PetrusekAbstract:The North American spiny-cheek crayfish, Orconectes Limosus , was most probably introduced into Europe only once, in 1890. The size of the founding population was just 90 individuals. Low genetic variability resulting from a bottleneck effect during introduction might therefore be supposed in European spiny-cheek crayfish populations. On the other hand, the fast spread of O. Limosus in Europe and colonisation of various habitats suggest that this species does not suffer from inbreeding depression due to an introduction bottleneck. We analysed 14 O. Limosus populations from the Czech Republic using allozyme electrophoresis to evaluate the level of intra- and among-population genetic variation. Out of eight well-scoring allozyme loci chosen for detailed analysis, six were variable in studied populations, suggesting that sufficient variability was maintained during the introduction. Genetic differentiation of Czech populations of the spiny-cheek crayfish was relatively low and did not show any clear geographic pattern, probably due to long-range translocations by humans.
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Invaders eating invaders: potential trophic interactions between the amphipod Dikerogammarus villosus and juvenile crayfish Orconectes Limosus
EDP Sciences, 2009Co-Authors: M. Buřià, Adam Petrusek, L. Kočí, A. Kouba, P. KozákAbstract:We investigated potential interspecific predation between two invasive crustacean species, currently widespread and co-occurring in European inland waters: the Ponto-Caspian amphipod Dikerogammarus villosus (Gammaridae) and the North American spiny-cheek crayfish Orconectes Limosus (Cambaridae). We evaluated interactions of adult specimens of D. villosus and juvenile O. Limosus (from the 3rd developmental stage – DS) under conditions with and without feeding. We used two different experimental setups: short-term (one-week) rearing in aquaria each containing 30 specimens of either single-species or mixed stock, and 20-daylong rearing in small circular plates with one individual of each species. In the aquaria, a significant effect of D. villosus presence on survival of O. Limosus stocks was found, with stronger influence on unfed stocks. Survival of D. villosus was not influenced by either O. Limosus presence or feeding. Direct predation of D. villosus on juvenile O. Limosus, predominantly on the 3rd DS, was often observed in the small plates. The 5th DS O. Limosus was killed only a few times and was already able to feed on adult D. villosus. Our results show that both species are able to affect each other negatively through intra-guild predation: D. villosus may successfully feed on juvenile O. Limosus (3rd and 4th DS), but larger crayfish can resist predation by the amphipod
Pavel Kozak - One of the best experts on this subject based on the ideXlab platform.
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Cross-species amplification of microsatellite markers in the invasive spiny-cheek crayfish [Orconectes Limosus]: assessment and application
Journal of applied genetics, 2010Co-Authors: Martin Hulak, Lenka Filipová, Pavel Kozak, V. Kašpar, M. Buřià, Adam PetrusekAbstract:The North American spiny-cheek crayfish,Orconectes Limosus (Cambaridae), endangered in its native range, is a widespread invasive species in European waters and conservationally important carrier of crayfish plague. However, its population structure is poorly known, and no informative genetic markers for the species are available. We tested cross-species transfer of microsatellite loci to spiny-cheek crayfish from 5 other crayfish species. Variability of 10 successfully amplifying loci derived from 4 species was then tested in 60 individuals ofO. Limosus originating from 3 natural populations: the river Danube at Bogyiszlo in Hungary, a pond in Starý Klicov, and the brook Cernovický, both in the Czech Republic. The allele number within the populations ranged from 4 to 10 alleles per locus, while heterozygosity levels varied from 0.650 to 0.900 forHo and from 0.660 to 0.890 forHe. No linkage disequilibrium and no null alleles were detected. The selected markers are useful for assessing population structure, intraspecific variation, and paternity studies in spiny-cheek crayfish.
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Seasonal Migrations of Introduced Orconectes Limosus (Rafinesque) to a Small Tributary of a Large River
2010Co-Authors: Antonín Kouba, Pavel KozakAbstract:A seasonal migration of introduced Orconectes Limosus (Rafinesque) between a brook and reservoir was observed in a small tributary of a large reservoir in southwest Czech Republic that was identified as suitable habitat for indigenous crayfish. Sixteen capture events (between April 2007 and October 2008) and one radio-telemetry study (from October to November 2007) were conducted. A significant trend of downstream migration to the reservoir was found in autumn. Orconectes Limosus showed the ability to move downstream rapidly (max. 139 m per day). Seasonal fluctuations in crayfish density were observed and suggested that the occurrence of crayfish in the brook goes through periodic changes. A lower water temperature in the brook throughout the year, and possible fish predation pressure in the reservoir, could contribute to this phenomenon. The occurrence of O. Limosus in reservoirs of big rivers, its periodic migrations, as well as the threat of potential crayfish plague transmission, accentuate their serious threat to indigenous crayfish. (Keywords.— abundance; invasive crayfish; periodic migrations; radio-telemetry; small stream).
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Chelae regeneration in European alien crayfish Orconectes Limosus (Rafinesque 1817)
Knowledge and Management of Aquatic Ecosystems, 2009Co-Authors: Miloš Buřič, Antonín Kouba, Pavel KozakAbstract:Crayfish chelae have important functions, including prey capture and manipulation, reproduction, defense against predators, and inter- and intraspecific interactions. Consequently a loss of chelae often occurs. Adult specimens of invasive spiny-cheek crayfish (Orconectes Limosus ) were reared from February to November 2008 to observe the ability to regenerate lost chelae. Percent molt increments (PMI) of postorbital carapace length (POCL), chela length (ChL) and width (ChW) were compared between crayfish with and without chelae. Regenerated chelae were found to grow faster (ChL, ChW) than initial chelae and POCL. This trend occurs in both reproductive and non-reproductive O. Limosus males and females. Values of 55.6 ± 0.06% for ChL and 50.0 ± 0.06% for ChW, compared to the initial chelae, were obtained in regenerated chelae of adult O. Limosus after one molt. After two molts regenerated chelae reached 67.6 ± 0.07% ChL and 69.7 ± 0.08% ChW of values for initial chelae. Growth rate of regenerated chelae decreased with an increase in chelae dimensions. Regenerated chelae were found to be more narrow (significantly lower ChW/ChL ratio) than initial chelae. Regenerating of chelae did not have any influence on POCL growth. This study presents evidence that the invasive O. Limosus possesses the ability of rapid substitution of lost chelae.
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Spring mating period in Orconectes Limosus: the reason for movement.
Aquatic Sciences, 2009Co-Authors: Miloš Buřič, Antonín Kouba, Pavel KozakAbstract:Thirteen adult Orconectes Limosus males (carapace length 32.5 ± 2.48 mm; weight 10.8 ± 2.63 g) were radio-tagged and tracked during and after the spring mating period, April–June 2008. Average distances moved per day were higher in the mating period (14.9 ± 21.4 m) due to mate searching activity. During the mating period, movement did not correlate with water temperature, and crayfish were active during daylight hours. They moved rapidly upstream and downstream, a maximum 118 and 95 m per day, respectively. When water temperature increased over 10°C, this initiated the end of mating and the start of spawning, and the spring migration abruptly ceased. An influence of water temperature on movements was observed during the non-reproductive period. Orconectes Limosus was highly mobile in small watercourses, signifying a threat of penetration into native crayfish habitats, and potentially enabling the transmission of crayfish plague. This threat was increased during the mating period due to increased activity.
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chelae regeneration in european alien crayfish Orconectes Limosus rafinesque 1817
Knowledge and Management of Aquatic Ecosystems, 2009Co-Authors: Miloš Buřič, Antonín Kouba, Pavel KozakAbstract:Key-words: non-indigenous, crayfish, invasive, chelae, regeneration, growth Crayfish chelae have important functions, including prey capture and manipulation, reproduction, defense against predators, and inter- and intraspecific interactions. Consequently a loss of chelae often occurs. Adult specimens of invasive spiny-cheek crayfish (Orconectes Limosus )w ere reared from February to November 2008 to observe the ability to regenerate lost chelae. Percent molt increments (PMI) of postorbital carapace length (POCL), chela length (ChL) and width (ChW) were compared between crayfish with and without chelae. Regenerated chelae were found to grow faster (ChL, ChW) than initial chelae and POCL. This trend occurs in both reproductive and non-reproductive O. Limosus males and females. Values of 55.6 ± 0.06% for ChL and 50.0 ± 0.06% for ChW, compared to the initial chelae, were obtained in regenerated chelae of adult O. Limosus after one molt. After two molts regenerated chelae reached 67.6 ± 0.07% ChL and 69.7 ± 0.08% ChW of values for initial chelae. Growth rate of regenerated chelae decreased with an increase in chelae dimensions. Regenerated chelae were found to be more narrow (significantly lower ChW/ChL ratio) than initial chelae. Regenerating of chelae did not have any influence on POCL growth. This study presents evidence that the invasive O. Limosus possesses the ability of rapid substitution of lost chelae.
Miloš Buřič - One of the best experts on this subject based on the ideXlab platform.
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Chelae regeneration in European alien crayfish Orconectes Limosus (Rafinesque 1817)
Knowledge and Management of Aquatic Ecosystems, 2009Co-Authors: Miloš Buřič, Antonín Kouba, Pavel KozakAbstract:Crayfish chelae have important functions, including prey capture and manipulation, reproduction, defense against predators, and inter- and intraspecific interactions. Consequently a loss of chelae often occurs. Adult specimens of invasive spiny-cheek crayfish (Orconectes Limosus ) were reared from February to November 2008 to observe the ability to regenerate lost chelae. Percent molt increments (PMI) of postorbital carapace length (POCL), chela length (ChL) and width (ChW) were compared between crayfish with and without chelae. Regenerated chelae were found to grow faster (ChL, ChW) than initial chelae and POCL. This trend occurs in both reproductive and non-reproductive O. Limosus males and females. Values of 55.6 ± 0.06% for ChL and 50.0 ± 0.06% for ChW, compared to the initial chelae, were obtained in regenerated chelae of adult O. Limosus after one molt. After two molts regenerated chelae reached 67.6 ± 0.07% ChL and 69.7 ± 0.08% ChW of values for initial chelae. Growth rate of regenerated chelae decreased with an increase in chelae dimensions. Regenerated chelae were found to be more narrow (significantly lower ChW/ChL ratio) than initial chelae. Regenerating of chelae did not have any influence on POCL growth. This study presents evidence that the invasive O. Limosus possesses the ability of rapid substitution of lost chelae.
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Spring mating period in Orconectes Limosus: the reason for movement.
Aquatic Sciences, 2009Co-Authors: Miloš Buřič, Antonín Kouba, Pavel KozakAbstract:Thirteen adult Orconectes Limosus males (carapace length 32.5 ± 2.48 mm; weight 10.8 ± 2.63 g) were radio-tagged and tracked during and after the spring mating period, April–June 2008. Average distances moved per day were higher in the mating period (14.9 ± 21.4 m) due to mate searching activity. During the mating period, movement did not correlate with water temperature, and crayfish were active during daylight hours. They moved rapidly upstream and downstream, a maximum 118 and 95 m per day, respectively. When water temperature increased over 10°C, this initiated the end of mating and the start of spawning, and the spring migration abruptly ceased. An influence of water temperature on movements was observed during the non-reproductive period. Orconectes Limosus was highly mobile in small watercourses, signifying a threat of penetration into native crayfish habitats, and potentially enabling the transmission of crayfish plague. This threat was increased during the mating period due to increased activity.
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chelae regeneration in european alien crayfish Orconectes Limosus rafinesque 1817
Knowledge and Management of Aquatic Ecosystems, 2009Co-Authors: Miloš Buřič, Antonín Kouba, Pavel KozakAbstract:Key-words: non-indigenous, crayfish, invasive, chelae, regeneration, growth Crayfish chelae have important functions, including prey capture and manipulation, reproduction, defense against predators, and inter- and intraspecific interactions. Consequently a loss of chelae often occurs. Adult specimens of invasive spiny-cheek crayfish (Orconectes Limosus )w ere reared from February to November 2008 to observe the ability to regenerate lost chelae. Percent molt increments (PMI) of postorbital carapace length (POCL), chela length (ChL) and width (ChW) were compared between crayfish with and without chelae. Regenerated chelae were found to grow faster (ChL, ChW) than initial chelae and POCL. This trend occurs in both reproductive and non-reproductive O. Limosus males and females. Values of 55.6 ± 0.06% for ChL and 50.0 ± 0.06% for ChW, compared to the initial chelae, were obtained in regenerated chelae of adult O. Limosus after one molt. After two molts regenerated chelae reached 67.6 ± 0.07% ChL and 69.7 ± 0.08% ChW of values for initial chelae. Growth rate of regenerated chelae decreased with an increase in chelae dimensions. Regenerated chelae were found to be more narrow (significantly lower ChW/ChL ratio) than initial chelae. Regenerating of chelae did not have any influence on POCL growth. This study presents evidence that the invasive O. Limosus possesses the ability of rapid substitution of lost chelae.
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invaders eating invaders potential trophic interactions between the amphipod dikerogammarus villosus and juvenile crayfish Orconectes Limosus
Knowledge and Management of Aquatic Ecosystems, 2009Co-Authors: Miloš Buřič, Adam Petrusek, Antonín Kouba, L. Kočí, Pavel KozakAbstract:Key-words: invasive species, interactions, intra-guild predation, survival, crayfish We investigated potential interspecific predation between two invasive crustacean species, currently widespread and co-occurring in European inland waters: the Ponto-Caspian amphipod Dikerogammarus villosus (Gammaridae) and the North American spiny-cheek crayfish Orconectes Limosus (Cambaridae). We evaluated interactions of adult specimens of D. villosus and juvenile O. Limosus (from the 3rd developmental stage ‐ DS) under conditions with and without feeding. We used two different experimental setups: short-term (one-week) rearing in aquaria each containing 30 specimens of either single-species or mixed stock, and 20-daylong rearing in small circular plates with one individual of each species. In the aquaria, a significant effect of D. villosus presence on survival of O. Limosus stocks was found, with stronger influence on unfed stocks. Survival of D. villosus was not influenced by either O. Limosus presence or feeding. Direct predation of D. villosus on juvenile O. Limosus ,p redominantly on the 3rd DS, was often observed in the small plates. The 5th DS O. Limosus was killed only a few times and was already able to feed on adult D. villosus. Our results show that both species are able to affect each other negatively through intra-guild predation: D. villosus may successfully feed on juvenile O. Limosus (3rd and 4th DS), but larger crayfish can resist predation by the amphipod.
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Evaluation of different marking methods for spiny-cheek crayfish (Orconectes Limosus)
Knowledge and Management of Aquatic Ecosystems, 2008Co-Authors: Miloš Buřič, Pavel Kozak, P. VíchAbstract:Different methods of marking were evaluated for Orconectes Limosus (CL = carapace length, 12–37 mm) under laboratory conditions: the use of passive integrated transponders, visible implant elastomers, visible implant alphanumeric tags, and cauterization. High survival (> 90%) was obtained with all methods tested. Tag retention and readability were evaluated immediately after marking, before and after ecdysis, with moult increments and number of moults been recorded. Marking using cauterization negatively affects the percent moult increment (PMI) of crayfish. The average PMI of 15 ± 0.88% did not differ between males (15 ± 1.41 mm) and females (15 ± 1.12 mm). It was found that PMI gradually decreased with an increase in CL. Sixty-one moults were observed, with 12 crayfish (6 juveniles and 6 adults) presenting two moults. Time between moults varied from 3 to 7 weeks. CL was increased with over 28 ± 2.68% due to two moults. Three females moulted twice after successful hatching and carrying of juveniles.
Jasna Peter-katalinić - One of the best experts on this subject based on the ideXlab platform.
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Identification of Neuropeptides from the Sinus Gland of the Crayfish Orconectes Limosus Using Nanoscale On-line Liquid Chromatography Tandem Mass Spectrometry
Molecular & cellular proteomics : MCP, 2004Co-Authors: Patrick Bulau, Rainer Keller, Iris Meisen, Tina Schmitz, Jasna Peter-katalinićAbstract:In this article, a novel and sensitive analytical strategy for direct characterization of neuropeptides from the X-Organ-sinus gland neurosecretory system of the crayfish Orconectes Limosus is presented. A desalted extract corresponding to 0.5 sinus gland equivalents was analyzed in a nanoflow liquid chromatography system coupled to quadrupole time-of-flight tandem mass spectrometry (nanoLC-QTOF MS/MS). The existence and structural identity of four crustacean hyperglycemic hormone precursor-related peptide variants and two new genetic variants of the pigment-dispersing hormone, not detected by conventional chromatographic systems, molecular cloning, or immunochemical methods before, was revealed. The here-presented approach of the combined LC-QTOF MS/MS technique is a powerful tool to discover new peptide hormones in biological systems, due to its sensitivity, accuracy, and speed.