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Norihiro Okada - One of the best experts on this subject based on the ideXlab platform.
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a microsatellite based genetic linkage map and putative sex determining genomic regions in lake victoria cichlids
Gene, 2015Co-Authors: Yu Kudo, Norihiro Okada, Masato Nikaido, Azusa Kondo, Hikoyu Suzuki, Kohta Yoshida, Kiyoshi KikuchiAbstract:Cichlid fishes in East Africa have undergone extensive adaptive radiation, which has led to spectacular diversity in their morphology and ecology. To date, genetic linkage maps have been constructed for several tilapias (riverine), Astatotilapia burtoni (Lake Tanganyika), and hybrid lines of Lake Malawi cichlids to facilitate genome-wide comparative analyses. In the present study, we constructed a genetic linkage map of the hybrid line of Lake Victoria cichlids, so that maps of cichlids from all the major areas of East Africa will be available. The genetic linkage map shown here is derived from the F2 progeny of an interspecific cross between Haplochromis chilotes and Haplochromis sauvagei and is based on 184 microsatellite and two single-nucleotide polymorphism (SNP) markers. Most of the microsatellite markers used in the present study were originally designed for other genetic linkage maps, allowing us to directly compare each linkage group (LG) among different cichlid groups. We found 25 LGs, the total length of which was 1133.2cM with an average marker spacing of about 6.09cM. Our subsequent linkage mapping analysis identified two putative sex-determining loci in cichlids. Interestingly, one of these two loci is located on cichlid LG5, on which the female heterogametic ZW locus and several quantitative trait loci (QTLs) related to adaptive evolution have been reported in Lake Malawi cichlids. We also found that V1R1 and V1R2, candidate genes for the fish pheromone receptor, are located very close to the recently detected sex-determining locus on cichlid LG5. The genetic linkage map study presented here may provide a valuable foundation for studying the chromosomal evolution of East African cichlids and the possible role of sex chromosomes in generating their genomic diversity.
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Isolation and characterization of microsatellite loci in the cichlid fish in Lake Victoria, Haplochromis chilotes
Molecular Ecology Resources, 2008Co-Authors: K. Maeda, Hirohiko Takeshima, Shinji Mizoiri, Norihiro Okada, Mutsumi Nishida, Hidenori TachidaAbstract:Twelve short tandem repeat markers were successfully isolated from a cichlid, Haplochromis chilotes, in Lake Victoria, and characterized in Haplochromis pyrrhocephalus. The microsatellite regions of these markers were found to have between two and 48 alleles with heterozygosity ranging from 0.07 to 0.97. No loci showed significant departures from the Hardy-Weinberg or linkage equilibrium after the Bonferroni correction (P > 0.05). Cross-species amplification in other cichlids of Lake Victoria, Haplochromis laparogramma, Lithochromis rubripinnis, L. rufus and Haplochromis sp. 'rockkribensis', was successful.
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permanent genetic resources isolation and characterization of microsatellite loci in the cichlid fish in lake victoria Haplochromis chilotes
Molecular Ecology Resources, 2008Co-Authors: K. Maeda, Hirohiko Takeshima, Shinji Mizoiri, Norihiro Okada, Mutsumi Nishida, Hidenori TachidaAbstract:Twelve short tandem repeat markers were successfully isolated from a cichlid, Haplochromis chilotes, in Lake Victoria, and characterized in Haplochromis pyrrhocephalus. The microsatellite regions of these markers were found to have between two and 48 alleles with heterozygosity ranging from 0.07 to 0.97. No loci showed significant departures from the Hardy–Weinberg or linkage equilibrium after the Bonferroni correction (P > 0.05). Cross-species amplification in other cichlids of Lake Victoria, Haplochromis laparogramma, Lithochromis rubripinnis, L. rufus and Haplochromis sp. ‘rockkribensis’, was successful.
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magp4 gene may contribute to the diversification of cichlid morphs and their speciation.
Gene, 2006Co-Authors: Naoki Kobayashi, Masakatsu Watanabe, Teiya Kijimoto, Koji Fujimura, Masumi Nakazawa, Kazuho Ikeo, Yuji Kohara, Takashi Gojobori, Norihiro OkadaAbstract:Lake Victoria harbors more than 300 species of cichlid fish, which are adapted to a variety of ecological niches with various morphological species-specific features. However, it is believed that these species arose explosively within the last 14,000 years and transcripts among Lake Victoria cichlid species are almost identical in sequence. These data prompted us to develop a DNA chip assay to compare patterns of gene expression among cichlid species. We prepared a DNA chip spotted with 6240 elements derived from cichlid expressed sequence tag (EST) clones and successfully characterized gene expression differences between the cichlid species Haplochromis chilotes and Haplochromis sp. "rockkribensis". We identified 14 transcripts that were differentially expressed between these species at an early developmental stage, 15 days post-fertilization (dpf), and several were further analyzed using quantitative real-time PCR (qPCR). One of these differentially expressed transcripts was a homolog of microfibril-associated glycoprotein 4 (magp4), a putative causative gene for the human inherited disease, Smith-Magenis syndrome (SMS), for which facial defects are among the phenotypic features. Further analysis of magp4 expression showed that magp4 was expressed in the jaw portion of cichlid fry and that expression profiles between Haplochromis chilotes and Haplochromis sp. "rockkribensis" differed during development. These data suggest that the differential expression of a gene associated with human cranial morphogenesis may be involved in the diversification of cichlid jaw morphs.
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Extensive analysis of ORF sequences from two different cichlid species in Lake Victoria provides molecular evidence for a recent radiation event of the Victoria species flock: identity of EST sequences between Haplochromis chilotes and Haplochromis s
Gene, 2004Co-Authors: Masakatsu Watanabe, Naoki Kobayashi, Yuji Kohara, Tadasu Shin-i, Tokumasa Horiike, Yoshio Tateno, Norihiro OkadaAbstract:The Lake Victoria Cichlid fishes have diverged very rapidly. The estimated 500 species inhabiting the lake are believed to have arisen within the last 14,000 years. The fishes' jaws and teeth have diverged markedly to adapt to different feeding behaviors and environments. To examine how the genomes of these fishes differentiated during speciation, we performed comparative analysis of expressed sequenced tag (EST) sequences. We constructed cDNA libraries derived only from the jaw portions of two cichlid species endemic to Lake Victoria. We sequenced 17,280 cDNA clones from Haplochromis chilotes and 9600 cDNA clones from Haplochromis sp. "Redtailsheller" and obtained 543 different genes common to both species. Of these genes, 441 were essentially identical between species and 102 contained base replacements in their open reading frame (ORF) or untranslated (UTR) regions. Comparative analysis of 71 selected sequences has revealed that while the degree of polymorphism is 0.0054/site for H. chilotes and 0.0047/site for H. sp. "Redtailsheller", genetic distance between the two species is 0.0031/site. The genetic distance particularly indicates that the two species diverged about 890,000 years ago.
Witte Frans - One of the best experts on this subject based on the ideXlab platform.
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Figure 10 from: de Zeeuw M, Westbroek I, van Oijen M, Witte F (2013) Two new species of zooplanktivorous haplochromine cichlids from Lake Victoria, Tanzania. ZooKeys 256: 1-34. https://doi.org/10.3897/zookeys.256.3871
2013Co-Authors: De Zeeuw Marnix, Westbroek Irene, Van Oijen Martien, Witte FransAbstract:Figure 10 - Plots of taxonomic measurements as a function of standard length. Body depth (BD), preorbital width (POW), lower jaw width (LJW) and lachrymal width (LaW). Open circles - Haplochromis argens from the Mwanza Gulf (Mw); closed circles - Haplochromis argens from the Emin Pasha Gulf (EP); triangles - Haplochromis goldschmidti. Power curves determined from GLM parameter estimates, solid line - Haplochromis argens from the Mwanza Gulf; dotted line - Haplochromis argens from the Emin Pasha Gulf; dashed line - Haplochromis goldschmidti, long dashed line (POW) - Haplochromis argens from both locations (MW + EP)
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Figure 5 from: de Zeeuw M, Westbroek I, van Oijen M, Witte F (2013) Two new species of zooplanktivorous haplochromine cichlids from Lake Victoria, Tanzania. ZooKeys 256: 1-34. https://doi.org/10.3897/zookeys.256.3871
2013Co-Authors: De Zeeuw Marnix, Westbroek Irene, Van Oijen Martien, Witte FransAbstract:Figure 5 - Preserved colours of Haplochromis argens sp. n. ♂ 67.3 mm SL (holotype, RMNH.PISC.83588). Scale bar equals 10 mm
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Figure 4 from: de Zeeuw M, Westbroek I, van Oijen M, Witte F (2013) Two new species of zooplanktivorous haplochromine cichlids from Lake Victoria, Tanzania. ZooKeys 256: 1-34. https://doi.org/10.3897/zookeys.256.3871
2013Co-Authors: De Zeeuw Marnix, Westbroek Irene, Van Oijen Martien, Witte FransAbstract:Figure 4 - Live colours of Haplochromis argens sp. n. A sexually active ♂, 59.3 mm SL (paratype, RMNH.PISC.83622), Emin Pasha Gulf B sexually active ♂, 72.1 mm SL (paratype, RMNH.PISC.84067), Mwanza Gulf
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Figure 7 from: de Zeeuw M, Westbroek I, van Oijen M, Witte F (2013) Two new species of zooplanktivorous haplochromine cichlids from Lake Victoria, Tanzania. ZooKeys 256: 1-34. https://doi.org/10.3897/zookeys.256.3871
2013Co-Authors: De Zeeuw Marnix, Westbroek Irene, Van Oijen Martien, Witte FransAbstract:Figure 7 - Skeletal elements of Haplochromis goldschmidti sp. n. A Right premaxilla, lateral view (RMNH.PISC.83695) B Right lower jaw, lateral view (RMNH.PISC.83695) C Lower pharyngeal element, dorsal view (RMNH.PISC.83701) D Lower pharyngeal element, lateral view (RMNH.PISC.83701). Scale bars equal 1 mm. Drawn by I. Westbroek
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Figure 3 from: de Zeeuw M, Westbroek I, van Oijen M, Witte F (2013) Two new species of zooplanktivorous haplochromine cichlids from Lake Victoria, Tanzania. ZooKeys 256: 1-34. https://doi.org/10.3897/zookeys.256.3871
2013Co-Authors: De Zeeuw Marnix, Westbroek Irene, Van Oijen Martien, Witte FransAbstract:Figure 3 - Skeletal elements of Haplochromis argens sp. n. A Right premaxilla, lateral view (RMNH.PISC.83705) B Right premaxilla, lateral (top) and occlusal (bottom) views (RMNH.PISC.83621), illustrating, for this species, a rare case of a posteriorly edentulous premaxilla C Right lower jaw, lateral view (RMNH.PISC.83697) D Lower pharyngeal element, dorsal view (RMNH.PISC. 83706) E Lower pharyngeal element, lateral view (RMNH.PISC.83706). Scale bars equal 1 mm. A, C, D drawn by I. Westbroek, B by M. van Oijen
De Zeeuw Marnix - One of the best experts on this subject based on the ideXlab platform.
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Figure 10 from: de Zeeuw M, Westbroek I, van Oijen M, Witte F (2013) Two new species of zooplanktivorous haplochromine cichlids from Lake Victoria, Tanzania. ZooKeys 256: 1-34. https://doi.org/10.3897/zookeys.256.3871
2013Co-Authors: De Zeeuw Marnix, Westbroek Irene, Van Oijen Martien, Witte FransAbstract:Figure 10 - Plots of taxonomic measurements as a function of standard length. Body depth (BD), preorbital width (POW), lower jaw width (LJW) and lachrymal width (LaW). Open circles - Haplochromis argens from the Mwanza Gulf (Mw); closed circles - Haplochromis argens from the Emin Pasha Gulf (EP); triangles - Haplochromis goldschmidti. Power curves determined from GLM parameter estimates, solid line - Haplochromis argens from the Mwanza Gulf; dotted line - Haplochromis argens from the Emin Pasha Gulf; dashed line - Haplochromis goldschmidti, long dashed line (POW) - Haplochromis argens from both locations (MW + EP)
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Figure 5 from: de Zeeuw M, Westbroek I, van Oijen M, Witte F (2013) Two new species of zooplanktivorous haplochromine cichlids from Lake Victoria, Tanzania. ZooKeys 256: 1-34. https://doi.org/10.3897/zookeys.256.3871
2013Co-Authors: De Zeeuw Marnix, Westbroek Irene, Van Oijen Martien, Witte FransAbstract:Figure 5 - Preserved colours of Haplochromis argens sp. n. ♂ 67.3 mm SL (holotype, RMNH.PISC.83588). Scale bar equals 10 mm
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Figure 4 from: de Zeeuw M, Westbroek I, van Oijen M, Witte F (2013) Two new species of zooplanktivorous haplochromine cichlids from Lake Victoria, Tanzania. ZooKeys 256: 1-34. https://doi.org/10.3897/zookeys.256.3871
2013Co-Authors: De Zeeuw Marnix, Westbroek Irene, Van Oijen Martien, Witte FransAbstract:Figure 4 - Live colours of Haplochromis argens sp. n. A sexually active ♂, 59.3 mm SL (paratype, RMNH.PISC.83622), Emin Pasha Gulf B sexually active ♂, 72.1 mm SL (paratype, RMNH.PISC.84067), Mwanza Gulf
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Figure 7 from: de Zeeuw M, Westbroek I, van Oijen M, Witte F (2013) Two new species of zooplanktivorous haplochromine cichlids from Lake Victoria, Tanzania. ZooKeys 256: 1-34. https://doi.org/10.3897/zookeys.256.3871
2013Co-Authors: De Zeeuw Marnix, Westbroek Irene, Van Oijen Martien, Witte FransAbstract:Figure 7 - Skeletal elements of Haplochromis goldschmidti sp. n. A Right premaxilla, lateral view (RMNH.PISC.83695) B Right lower jaw, lateral view (RMNH.PISC.83695) C Lower pharyngeal element, dorsal view (RMNH.PISC.83701) D Lower pharyngeal element, lateral view (RMNH.PISC.83701). Scale bars equal 1 mm. Drawn by I. Westbroek
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Figure 3 from: de Zeeuw M, Westbroek I, van Oijen M, Witte F (2013) Two new species of zooplanktivorous haplochromine cichlids from Lake Victoria, Tanzania. ZooKeys 256: 1-34. https://doi.org/10.3897/zookeys.256.3871
2013Co-Authors: De Zeeuw Marnix, Westbroek Irene, Van Oijen Martien, Witte FransAbstract:Figure 3 - Skeletal elements of Haplochromis argens sp. n. A Right premaxilla, lateral view (RMNH.PISC.83705) B Right premaxilla, lateral (top) and occlusal (bottom) views (RMNH.PISC.83621), illustrating, for this species, a rare case of a posteriorly edentulous premaxilla C Right lower jaw, lateral view (RMNH.PISC.83697) D Lower pharyngeal element, dorsal view (RMNH.PISC. 83706) E Lower pharyngeal element, lateral view (RMNH.PISC.83706). Scale bars equal 1 mm. A, C, D drawn by I. Westbroek, B by M. van Oijen
Tom Stonier - One of the best experts on this subject based on the ideXlab platform.
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Testing clove oil as an anaesthetic for long-distance transport of live fish: The case of the Lake Victoria cichlid Haplochromis obliquidens
Journal of Applied Ichthyology, 2006Co-Authors: Herbert Kaiser, P. Collett, K. Czypionka, Anthony Green, K. Orr, P. Pattrick, Gregg Brill, J. Cahill, Rens Scheepers, Tom StonierAbstract:Clove oil can be used as an anaesthetic in the handling of marine and freshwater fish. Few studies report on its use for periods up to 48 h, for example, under long-distance transport conditions. This study tested the effect of different clove oil concentrations for 1-48 h on recovery and survival of the cichlid Haplochromis obliquidens, an ornamental fish species endemic to Lake Victoria. Haplochromis obliquidens were anaesthetized for 1 h using 5-25 mu l L-1 clove oil. There was no correlation between clove oil concentration and post-anaesthesia recovery time (P = 0.15). On average, fish recovered within 9.5 +/- 2 min, and no fish died within 24 h after recovery. Results from exposure of fish to 18-20 mu l L-1 clove oil for up to 48 h suggested a narrow margin of safety as this concentration range induced mortality. At 18 mu l L-1 recovery times ranged from 3 to 43 min between 24 and 36 h exposure, while fish exposed longer than 36 h recovered within 1-10 min, or within 1-2 min after 44-48 h. At the end of a 48-h transport experiment total ammonia levels were higher in transport water containing anaesthetized fish than for non-anaesthetized fish (1.65 +/- 0.19 and 0.54 +/- 0.08 mg L-1 NH4+ NH3, respectively). The combined use of clove oil and the selective ammonium ion exchanger zeolite was considered feasible as ammonia levels could be reduced by up to 82% compared to control bags without zeolite.
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Testing clove oil as an anaesthetic for long‐distance transport of live fish: the case of the Lake Victoria cichlid Haplochromis obliquidens
Journal of Applied Ichthyology, 2006Co-Authors: Horst Kaiser, P. Collett, K. Czypionka, P. Pattrick, Gregg Brill, J. Cahill, Rens Scheepers, Andy J. Green, Kyla K. Orr, Tom StonierAbstract:Summary Clove oil can be used as an anaesthetic in the handling of marine and freshwater fish. Few studies report on its use for periods up to 48 h, for example, under long-distance transport conditions. This study tested the effect of different clove oil concentrations for 1–48 h on recovery and survival of the cichlid Haplochromis obliquidens, an ornamental fish species endemic to Lake Victoria. Haplochromis obliquidens were anaesthetized for 1 h using 5–25 μl L−1 clove oil. There was no correlation between clove oil concentration and post-anaesthesia recovery time (P = 0.15). On average, fish recovered within 9.5 ± 2 min, and no fish died within 24 h after recovery. Results from exposure of fish to 18–20 μl L−1 clove oil for up to 48 h suggested a narrow margin of safety as this concentration range induced mortality. At 18 μl L−1 recovery times ranged from 3 to 43 min between 24 and 36 h exposure, while fish exposed longer than 36 h recovered within 1–10 min, or within 1–2 min after 44–48 h. At the end of a 48-h transport experiment total ammonia levels were higher in transport water containing anaesthetized fish than for non-anaesthetized fish (1.65 ± 0.19 and 0.54 ± 0.08 mg L−1 NH + NH3, respectively). The combined use of clove oil and the selective ammonium ion exchanger zeolite was considered feasible as ammonia levels could be reduced by up to 82% compared to control bags without zeolite.
Hidenori Tachida - One of the best experts on this subject based on the ideXlab platform.
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Isolation and characterization of microsatellite loci in the cichlid fish in Lake Victoria, Haplochromis chilotes
Molecular Ecology Resources, 2008Co-Authors: K. Maeda, Hirohiko Takeshima, Shinji Mizoiri, Norihiro Okada, Mutsumi Nishida, Hidenori TachidaAbstract:Twelve short tandem repeat markers were successfully isolated from a cichlid, Haplochromis chilotes, in Lake Victoria, and characterized in Haplochromis pyrrhocephalus. The microsatellite regions of these markers were found to have between two and 48 alleles with heterozygosity ranging from 0.07 to 0.97. No loci showed significant departures from the Hardy-Weinberg or linkage equilibrium after the Bonferroni correction (P > 0.05). Cross-species amplification in other cichlids of Lake Victoria, Haplochromis laparogramma, Lithochromis rubripinnis, L. rufus and Haplochromis sp. 'rockkribensis', was successful.
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permanent genetic resources isolation and characterization of microsatellite loci in the cichlid fish in lake victoria Haplochromis chilotes
Molecular Ecology Resources, 2008Co-Authors: K. Maeda, Hirohiko Takeshima, Shinji Mizoiri, Norihiro Okada, Mutsumi Nishida, Hidenori TachidaAbstract:Twelve short tandem repeat markers were successfully isolated from a cichlid, Haplochromis chilotes, in Lake Victoria, and characterized in Haplochromis pyrrhocephalus. The microsatellite regions of these markers were found to have between two and 48 alleles with heterozygosity ranging from 0.07 to 0.97. No loci showed significant departures from the Hardy–Weinberg or linkage equilibrium after the Bonferroni correction (P > 0.05). Cross-species amplification in other cichlids of Lake Victoria, Haplochromis laparogramma, Lithochromis rubripinnis, L. rufus and Haplochromis sp. ‘rockkribensis’, was successful.
