Chromosome Mapping of Repetitive Sequences in <i>Rachycentron canadum</i> (Perciformes: Rachycentridae): Implications for Karyotypic Evolution and Perspectives for Biotechnological Uses

Jacobina, Uedson Pereira; Cioffi, Marcelo de Bello; Souza, Luiz Gustavo Rodrigues; Calado, Leonardo Luiz; Tavares, Manoel; Manzella, João; Bertollo, Luiz Antonio Carlos; Molina, Wagner Franco

doi:https://doi.org/10.1155/2011/218231

BioMed Research International

On this page

Abstract Introduction Methods Results Discussion Acknowledgments References Copyright Related Articles

Research Article | Open Access

Volume 2011 | Article ID 218231 | https://doi.org/10.1155/2011/218231

Chromosome Mapping of Repetitive Sequences in Rachycentron canadum (Perciformes: Rachycentridae): Implications for Karyotypic Evolution and Perspectives for Biotechnological Uses

Uedson Pereira Jacobina,¹Marcelo de Bello Cioffi,²Luiz Gustavo Rodrigues Souza,³Leonardo Luiz Calado,¹Manoel Tavares,⁴João Manzella,⁴Luiz Antonio Carlos Bertollo,²and Wagner Franco Molina¹

Academic Editor: Brynn Levy

Received13 Sept 2010

Accepted01 Feb 2011

Published30 Mar 2011

Abstract

The cobia, Rachycentron canadum, a species of marine fish, has been increasingly used in aquaculture worldwide. It is the only member of the family Rachycentridae (Perciformes) showing wide geographic distribution and phylogenetic patterns still not fully understood. In this study, the species was cytogenetically analyzed by different methodologies, including Ag-NOR and chromomycin A₃ (CMA₃)/DAPI staining, C-banding, early replication banding (RGB), and in situ fluorescent hybridization with probes for 18S and 5S ribosomal genes and for telomeric sequences (TTAGGG)_n. The results obtained allow a detailed chromosomal characterization of the Atlantic population. The chromosome diversification found in the karyotype of the cobia is apparently related to pericentric inversions, the main mechanism associated to the karyotypic evolution of Perciformes. The differential heterochromatin replication patterns found were in part associated to functional genes. Despite maintaining conservative chromosomal characteristics in relation to the basal pattern established for Perciformes, some chromosome pairs in the analyzed population exhibit markers that may be important for cytotaxonomic, population, and biodiversity studies as well as for monitoring the species in question.

1. Introduction

The cobia (Rachycentron canadum) is the only member of the family Rachycentridae (Perciformes) found in tropical seas worldwide. It is highly valued on the international fish market and is a promising species for marine aquaculture (Kaiser and Holt [1]; Liao et al. [2]; Benetti et al. [3]; Benetti et al. [4]). Among its favorable breeding traits are easy adaptation, prolificacy, rapid growth, and meat quality (Frank et al. [5]; Arnold et al. [6]). Although well-established breeding technology is available, there is little genetic information to guide biotechnological initiatives and/or genetic improvement of the species, especially with respect to cytogenetic aspects.

Cytogenetic analyses in fish have been used in natural environments to characterize cryptic species and/or populations (Bertollo et al. [7]; Jacobina et al. [8]; Cioffi et al. [9]) and identify polymorphisms (Mantovani et al. [10]; Molina and Galetti [11]), inventories of existing biodiversity (Galetti Jr. et al. [12]; Artoni et al. [13]), in addition to chromosomal evolution in large taxonomic groups (e.g., Bertollo et al. [7]; Molina [14]). The information obtained has contributed to a better understanding of genetic diversity, monitoring, and conservation, as well as providing elements for a rational exploitation of fish stocks.

Current approaches, particularly involving the manipulation of chromosomal sets, have gone beyond the experimental field and are being increasingly used in aquaculture (Ocalewicz et al. [15]). From the technological viewpoint, the chromosomal data in fish have created conditions for implementing ploidy handling protocols aimed at increased growth and/or weight gain (Beardmore et al. [16]; Jankun et al. [17]), gynogenetic production (Devlin and Nagahama, [18]; Piferrer et al. [19]; Chen et al. [20]), establishment of monosex cultivations (Coimbra et al. [21]; Chen et al. [20]), and physical identification of quantitative trait loci (QTLs) (Ning et al. [22]) for several marine or fresh water species.

Because of the growing economic importance and increasingly sophisticated cultivation techniques, recent offshore commercial breeding initiatives of R. canadum stocks from the Western Atlantic have been very successful (Benetti et al. [4]). In order to get new useful characters for comparative genomics at chromosomal levels and provide adequate conditions for future uses of genetic improvement and biotechnological innovations, a resolutive chromosomal characterization of this species is presented here for the first time, using conventional Giemsa staining, C-banding, position and frequency of nucleoli organizer regions (NORs), CMA₃ and DAPI fluorochrome staining, physical mapping of repetitive sequences using fluorescent in situ hybridization (FISH) with 18S and 5S rDNA probes and telomeric sequences (TTAGGG)_n, in addition to replication banding patterns by the incorporation of base analogue 5-BrdU in this species.

2. Material and Methods

Cytogenetic analyses were developed from a sample of 40 cobia fry, weighing around 35 grams, obtained from a commercial marine fish culture farm located in the state of Pernambuco, in Northeastern Brazil. The specimens were previously submitted to in vivo mitotic stimulation for 24 hours, using intramuscular and intraperitoneal inoculation of fungal and bacterial antigen complexes (Molina [23]), anesthetized with clove oil (eugenol) and sacrificed to remove the renal tissue. Metaphasic chromosomes were obtained from cell suspensions of anterior rim fragments, according to short-term in vitro methodology (Gold Jr. et al. [24]).

The cell suspension obtained was dropped onto clean slides and covered with a film of distilled water heated to 60°C. The chromosomes were stained with a solution of 5% Giemsa, and 30 metaphases of each individual were analyzed to determine the number of chromosomes. Males and females were identified by macroscopic or histologic examination of the gonads. The best metaphases were photographed under an Olympus BX50 epifluorescence microscope equipped with a DP70 digital image capture system.

2.1. Chromosome Banding

The heterochromatic regions and ribosomal sites were identified by techniques proposed by Sumner [25] and Howell and Black [26], respectively. The CMA₃/DAPI double-staining technique was employed for CMA₃ banding, using DAPI (4′,6-diamidino-2-phenylindole) as counterstain (Barros-e-Silva and Guerra, [27]). Slides aged for 3 days were stained with CMA₃ (0.1 mg/mL) for 60 min and restained with DAPI (1 μg/mL) for 30 min. Next, the slides were mounted in glycerol : McIlvaine buffer, pH 7.0 (1 : 1) and aged for three days before analysis under epifluorescence microscope equipped with appropriate filters.

2.2. Replication Banding

Replication bands were obtained in 10 specimens of R. canadum using in vivo incorporation of the base analog 5-Bromo-2-deoxyuridine (5-BrdU), following methodology developed by Giles et al. [28], with some modifications. A solution of 5-BrdU (5 mg/mL in 0.9% NaCl solution) was injected intraperitoneally into each specimen at a proportion of 1 mL/100 g of body weight, 6 h (early S phase) before animal sacrifice to obtain mitotic chromosomes. The FPG (Fluorochrome Photolysis Giemsa) staining method was used to reveal RBG (Replication bands by bromodeoxyuridine using Giemsa) bands. The slides with chromosomal preparations were washed in 2 × SSC saline solution. They were then stained with Hoescht 33258 solution (Sigma) (1 mg of Hoescht in 1 mL of methanol and 100 mL of 0.5 × SSC) for 40 min in a dark chamber, washed in distilled water, covered with a 2 × SSC film, and exposed to ultraviolet light (254 ηm) at a distance of 10 cm, for 1 h. The slides were then incubated in 2 × SSC buffer for 90 minutes and stained with 6% Giemsa solution (pH 6.8) for 10 minutes.

2.3. Chromosome Hybridization Probes

Two tandem-arrayed DNA sequences isolated from the Hoplias malabaricus (Teleostei, Characiformes) genome were used. The first probe contained a 5S rDNA repeat copy and included 120 base pairs (bp) of the 5S rRNA encoding gene and 200 bp of the nontranscribed spacer (NTS) [29]. The second probe corresponded to a 1,400 bp segment of the 18S rRNA gene obtained via PCR from nuclear DNA (Cioffi et al. [30]). The 18S rDNA probe was labeled by nick translation with DIG-11-dUTP, according to the manufacturer’s specifications (Roche) and the 5S rDNA probe was labeled with biotin-14-dATP by nick translation, also according to the manufacturer’s specifications (Bionick Labelling System, Invitrogen).

The telomeric DNA sequence (TTAGGG)_n was also used as a probe. This probe was generated by PCR (PCR DIG-Probe Synthesis Kit, Roche) in the absence of template using (TTAGGG)₅ and (CCCTAA)₅ as primers (Ijdo et al. [31]).

2.4. Chromosome Hybridization and Analysis

Fluorescent in situ hybridization (FISH) was performed on mitotic chromosome spreads (Pinkel et al., [32]). The metaphase chromosome slides were incubated with RNAse (40 μg/mL) for 1.5 h at 37°C. After denaturation of chromosomal DNA in 70% formamide, spreads were incubated in 2 × SSC for 4 min at 70°C. Hybridization mixtures containing 100 ng of denatured probe, 10 mg/mL dextran sulfate, 2 × SSC, and 50% formamide in a final volume of 30 μl were dropped onto the slides, and hybridization was performed overnight at 37°C in a moist chamber. Posthybridization washes were carried out at 37°C in 2 × SSC, 50% formamide for 15 min, followed by a second wash in 2 × SSC for 15 min, and a final wash at room temperature in 4 × SSC for 15 min. Signal detection was performed using avidin-FITC (Sigma) for the 5S rDNA probe and anti-digoxigenin-rhodamine (Roche) for 18S rDNA and (TTAGGG)_n probes. One-color FISH was performed to detect (TTAGGG)_n repeats, while 5S and 18S rDNA were detected by double-FISH. The posthybridization washes were performed in a shaker (150 rpm). The chromosomes were counterstained with DAPI (1.2 μg/mL). FISH analysis was carried out with an epifluorescence microscope (Olympus BX50) and chromosomal plates were captured by the CoolSNAP system, Image Pro Plus, 4.1 (Media Cybernetics).

2.5. Chromosome Measures and Idiogram

Determination of chromosome types (Levan et al. [33]) and their measures were obtained using Image Tools 0.8.1 software, from five complete metaphases of R. canadum, where the locations of primary restrictions and telomeric regions of each chromosome were clearly defined. Total chromosome length (S), arm ratio (AR = long/short arm), in addition to size and position of heterochromatic blocks (numerical data not shown) were determined. An idiogram with chromosomal data for the species was created, using the Easy Idio program (Diniz and Xavier [34]), showing the position of 18S and 5s rDNA sites, late replication bands, and telomeric sequences.

3. Results

R. canadum has chromosomes, with a chromosomal formula composed of a submetacentric pair (sm), two subtelocentric pairs (st) and 21 acrocentric pairs (a), with a fundamental number (FN) of 54 (Figure 1(a)). Chromosome size ranged from 4.49 to 1.55 μm. The largest chromosome pair (2nd pair), subtelocentric, exhibited secondary constriction in the short arm (Figure 1(a)), which showed polymorphic behavior, causing substantial homologue size variation. This polymorphism was evidenced by both conventional staining and in chromosomes submitted to the other chromosome bandings.

(a)

(b)

(c)

(d)

(e)

Figure 1

Karyotypes of Rachycentron canadum. Conventional staining (a) highlighting the Ag-NOR sites in chromosome 2; (b) C-banding, highlighting the NORs as CMA₃⁺/DAPI⁻ heterochromatic regions; (c) replication bands, showing 18S (pair 2) and 5S (pairs 3 and 13) rDNA sites with early replication; (d) double-FISH with 18S (pink) and 5S (green) rDNA probes, showing the location of 18S rDNA sites in pair 2 and of 5S rDNA sites in pairs 3 and 13; (e) FISH with (TTAGGG)_n sequences showing the location of telomeric sites in the chromosomes (orange). Bar = 5 μm.

C-positive heterochromatic blocks were observed in the pericentromeric regions of the 1st pair (sm), in the centromeric and telomeric position (reduced content) in most of the acrocentric chromosomes, in the terminal position on the long arm of the 3rd pair (st) and in the interstitial region of the long arm of some chromosome pairs. Secondary constriction, present in the 2nd subtelocentric pair, was heterochromatic (CMA⁺/DAPI⁻), corresponding to the location of the Ag-NOR sites (Figures 1(a) and 1(b)).

In situ hybridization with 18S and 5S rDNA probes characterized a nonsyntenic condition for these ribosomal subunits. The two 18S rDNA sites detected were located in the C⁺/CMA⁺/DAPI⁻ region of the short arm of the 2nd chromosome pair. Conversely, four 5S rDNA sites were detected and mapped in the terminal position of the long arm of the 3rd pair and on the short arm of the 13th pair of chromosomes, both colocated with heterochromatic bands (Figure 1(d)).

FISH with telomeric probes (TTAGGG)n showed no ectopic signals, other than those present in the terminal region of the chromosome complement (Figure 1(e)). The wide range in telomeric signal intensity observed between chromosome pairs was markedly higher in some pairs than in others (Figure 1(e)).

The replication band pattern enabled a better identification of chromosome pairs (Figures 1(c) and 2). Early replication bands coincided with the euchromatic chromosome regions. The heterochromatin blocks identified by C-banding showed a synchronous pattern of late replication. Interestingly, the heterochromatinized 18S and 5S rDNA sites exhibited a typical initial replication pattern.

4. Discussion

The karyotype patterns of R. canadum are similar to those considered basal and conserved in most Perciformes fish. These symplesiomorphies are characterized by a diploid number of chromosomes equal to 48, karyotypes composed mainly of acrocentric chromosomes, simple NORs, and a reduced amount of heterochromatin (Molina [14]). Indeed, this relatively heterochromatin-poor karyotypic pattern, preferentially located in the pericentromeric region of acrocentric chromosomes, has been identified in several groups of marine Perciformes (e.g., Molina and Galetti Jr., [11]; Molina and Bacurau [35]; De Araújo et al. [36]). However, the presence of six bi-armed chromosomes (pairs 1, 2, and 3) in the karyotype of R. canadum reflects the more pronounced diversification in the karyotypic macrostructure of this species, indicating the occurrence of pericentric inversions associated to chromosomal evolution. Pericentric inversions are the prevalent evolutionary events in some groups of marine fish, such as Pomacentridae, Carangidae, and Apogonidae (Molina and Galetti Jr. [37]; Rodrigues et al. [38]; De Araújo et al. [36]) and have been reported as being the main mechanism of chromosomal diversification in Perciformes (Galetti Jr. et al. [39]).

Replication bands in fish chromosomes are still restricted to a reduced number of species. Although the R band patterns produced help achieve better homologue pairing, the symmetrical karyotype and relatively small size of R. canadum chromosomes enable more precise chromosomal individualization, as observed in a number of other fish species. The replication patterns obtained revealed the presence of three functional groups of chromatin in the karyotype of this species. The first corresponds to euchromatic regions, exhibiting the characteristic pattern of initial replication. The second group corresponds to heterochromatic regions composed of ribosomal gene repeats, with initial replication and where the genic clusters of 18S rDNA showed characteristically strong fluorescence with GC-specific fluorochromes. A similar condition was identified earlier in three species of the genus Leporinus (Anostomidae), in which intensely GC-rich positive mitramycin bands (MM⁺) also showed an initial replication pattern, while medium- or low-mitramycin fluorescence bands exhibited late replication (Molina and Galetti Jr. [40]). Finally, the third group of chromatin from R. canadum corresponds to repetitive DNAs with late replication, exhibiting no positive response to AT or GC-specific fluorochromes.

In general, replication bands indicate less heterogeneity in heterochromatins from R. canadum, compared to other species (Molina and Galetti Jr. [40]). This apparent composition homogeneity in the heterochromatic portions of the R. canadum genome may reflect the heterochromatic segments conserved in the karyotype. Such a situation seems to be particularly disseminated in Perciformes, suggesting the occurrence of similar chromosomal diversification mechanisms in phylogenetically similar groups, characterizing karyotypic orthoselection processes (Molina [14]). Despite the controversies regarding the different compositions and functionalities of heterochromatins and their evolutionary role (Allshire [41]; Huisinga et al. [42]; Djupedal and Ekwall, [43]), analysis of their location, distribution, and composition has been essential in the chromosomal characterization of many fish groups and often effective as cytotaxonomic markers (Moreira-Filho and Carlos Bertollo [44]; Sola et al. [45]).

Martins and Galetti Jr. [46] proposed that the location of 5S and 18S rDNA sites in different chromosomes, as observed for most vertebrates, could allow these loci to evolve independently, since their divergent functional dynamics requires a physical distance. This divergent location of 18S and 5S rDNA loci seems to be the most common situation observed in fish, as well as in other vertebrates (Lucchini et al. [47]; Suzuki et al. [48]). However, although present in smaller numbers, syntenic or even equilocal arrangements of these rDNA families have also been observed (Fujiwara et al. [49]), possibly even characterizing a frequent condition in some groups, such as Channichthyidae (Mazzei et al. [50]).

The occurrence of evolutionary dynamics involved in these genes in some species has been confirmed by a greater variability in the distribution of 45S rDNA sites in the chromosomes (Mantovani et al. [51]). Similarly, heterochromatins associated to ribosomal genes play a different evolutionary role in R. canadum, involving composition, position, and/or functional aspects, compared to other merely heterochromatic regions of the karyotype. Whereas the first contained high GC levels and replication at the onset of the S phase, the remaining heterochromatic portions showed late replication and CMA₃/DAPI staining neutrality. However, examples of nonheterochromatinized ribosomal sites are also present in different fish groups (e.g., Fujiwara et al. [49]; Ráb et al. [52]; Rábová et al. [53]).

Telomeric (TTAGGG)_n sequences are present in the telomeres of vertebrate chromosomes, and their analysis allows one to establish the presence of chromosomal rearrangements, such as Robertsonian fusions or inversions, which are involved in chromosomal evolution (Meyne et al. [54]). These sequences have been used to identify chromosomal rearrangements in fish (Saitoh et al. [55]), such as some species of Salmoniformes, Salvelinus namaycush, S. fontinalis, S. alpinus, and Oncorhynchus spp. (Reed and Phillips [56]; Phillips and Reed [57]); Characiformes, Hoplias malabaricus (Cioffi and Bertollo [58]), and Erythrinus erythrinus (Cioffi et al. [59]); Anguilliformes and Perciformes (Salvadori et al. [60]; Gornung et al. [61]; Caputo et al. [62]). FISH with the telomeric probe (TTAGGG)_n revealed hybridization signals in the telomeric region of the chromosomes. Hybridization signals exhibited intensity variations in some chromosome pairs, suggesting the occurrence of telomeric repeat amplification or their dispersion into telomeric heterochromatic regions. Interstitial telomeric sites (ITS) were not detected, which indicates that Robertsonian fusions or chromosomal translocations were likely not involved in the karyotypic evolution of R. canadum. However, we cannot rule out this possibility, since it is known that loss of telomeric sequences may occur after such rearrangements (Slijepcevic [63]; Nanda et al. [64], De Almeida-Toledo et al. [65]). Maintaining the basal diploid number for Perciformes, as well as the relative conservatism of the karyotype, in fact do not appear to indicate that recent chromosomal rearrangements have occurred in the chromosomal evolution of cobia fish.

The phylogenetic relationships of the family Rachycentridae, based on morphological characters, suggest its proximity with Nematistiidae, Echeneidae, Carangidae, and Coryphaenidae (Johnson [66]; Springer and Smith-Vaniz [67]). Indeed, the evolutionary proximity between families has been corroborated by cytogenetic data available for a number of species belonging to these groups (Caputo et al. [68]; Sola et al. [45]; Rodrigues et al. [38]; Chai et al. [69]; present study), complemented by the investigation of mitochondrial sequences (Cit B) (Reed et al. [70]) and larval morphology (Ditty and Shaw [71]), which point to Coryphaenidae as a sister group of R. canadum.

R. canadum has emerged as an important model for marine fish culture. Nevertheless, there are few genetic studies on this species (Garber et al. [72]; Liu et al. [73]). Given that it belongs to a monotypic family with vast worldwide distribution in tropical and subtropical areas, its populations may be subject to marked genetic structuring, like others species with similar biogeographic characteristics. The presence of some chromosome pairs, such as the first three (sm, st, st, resp.) of the karyotype is particularly indicated as cytotaxonomic markers in the cobia population studied, considering its morphology, size, presence of heterochromatin, and 18S and 5S rDNA sites. In this respect, such chromosomes may contain important characters for interpopulation approaches, biodiversity characterization and monitoring, in addition to contributing to future biotechnological assays.

Acknowledgments

This study was financed by the National Research Council (CNPq) (Process no. 557280/05-2) and the REUNI scholarship (Ministry of Education) awarded to UPJ. The authors wish to thank the Aqualider Aquaculture Company for cession the specimens used in the study. They also express their appreciation to Dr. Marcelo Guerra for providing telomere probes for FISH analysis.

References

J. B. Kaiser and G. J. Holt, “Cobia: a new species for aquaculture in the US,” World Aquaculture Magazine, vol. 35, pp. 12–14, 2004.
View at: Google Scholar
I. C. Liao, T. S. Huang, W. S. Tsai, C. M. Hsueh, S. L. Chang, and E. M. Leaño, “Cobia culture in Taiwan: current status and problems,” Aquaculture, vol. 237, no. 1–4, pp. 155–165, 2004.
View at: Publisher Site | Google Scholar
D. D. Benetti, M. R. Orhun, I. Zink et al., “Aquaculture of cobia (Rachycentron canadum) in the Americas and the Caribbean,” in Cobia Aquaculture: Research, Development and Commercial Production, I. C. Liao and E. M. Leano, Eds., pp. 57–78, World Aquaculture Society, New Orleans, La, USA, 2007.
View at: Google Scholar
D. D. Benetti, B. O'Hanlon, J. A. Rivera, A. W. Welch, C. Maxey, and M. R. Orhun, “Growth rates of cobia (Rachycentron canadum) cultured in open ocean submerged cages in the Caribbean,” Aquaculture, vol. 302, no. 3-4, pp. 195–201, 2010.
View at: Publisher Site | Google Scholar
J. S. Frank, J. T. Ogle, J. M. Lotz, L. C. Nicholson, D. N. Barnes, and K. M. Larsen, “Spontaneous spawning of cobia, Rachycentron canadum, induced by human chorionic gonadotropin (HCG), with comments on fertilization, hatching and larval development,” Proceedings of the Gulf and Caribbean Fisheries Institute, vol. 52, pp. 598–609, 2001.
View at: Google Scholar
C. R. Arnold, J. B. Kaiser, and G. J. Holt, “Spawning of cobia Rachycentron canadum in captivity,” Journal of the World Aquaculture Society, vol. 33, no. 2, pp. 205–208, 2002.
View at: Google Scholar
L. A. C. Bertollo, G. G. Born, J. A. Dergam, A. S. Fenocchio, and O. Moreira-Filho, “A biodiversity approach in the neotropical Erythrinidae fish, Hoplias malabaricus. Karyotypic survey, geographic distribution of cytotypes and cytotaxonomic considerations,” Chromosome Research, vol. 8, no. 7, pp. 603–613, 2000.
View at: Publisher Site | Google Scholar
U. P. Jacobina, P. R. A. M. Affonso, P. L. S. Carneiro, and J. A. Dergam, “Biogeography and comparative cytogenetics between two populations of Hoplias malabaricus (Bloch, 1794) (Ostariophysi: Erythrinidae) from coastal basins in the State of Bahia, Brazil,” Neotropical Ichthyology, vol. 7, no. 4, pp. 617–622, 2009.
View at: Google Scholar
M. B. Cioffi, C. Martins, L. Centofante, U. Jacobina, and L. A. C. Bertollo, “Chromosomal variability among allopatric populations of erythrinidae fish Hoplias malabaricus: mapping of three classes of repetitive DNAs,” Cytogenetic and Genome Research, vol. 125, no. 2, pp. 132–141, 2009.
View at: Publisher Site | Google Scholar
M. Mantovani, L. D. D. S. Abel, C. A. Mestriner, and O. Moreira-Filho, “Accentuated polymorphism of heterochromatin and nucleolar organizer regions in Astyanax scabripinnis (Pisces, Characidae): tools for understanding karyotypic evolution,” Genetica, vol. 109, no. 3, pp. 161–168, 2000.
View at: Publisher Site | Google Scholar
W. F. Molina and P. M. Galetti Jr., “Robertsonian rearrangements in the reef fish Chromis (Perciformes, Pomacentridae) involving chromosomes bearing 5s rRNA genes,” Genetics and Molecular Biology, vol. 25, no. 4, pp. 373–377, 2002.
View at: Google Scholar
P. M. Galetti Jr., W. F. Molina, P. R. A. M. Affonso, and C. T. Aguilar, “Assessing genetic diversity of Brazilian reef fishes by chromosomal and DNA markers,” Genetica, vol. 126, no. 1-2, pp. 161–177, 2006.
View at: Publisher Site | Google Scholar
R. F. Artoni, M. R. Vicari, M. C. Almeida, O. Moreira-Filho, and L. A. C. Bertollo, “Karyotype diversity and fish conservation of southern field from South Brazil,” Reviews in Fish Biology and Fisheries, vol. 19, no. 3, pp. 393–401, 2009.
View at: Publisher Site | Google Scholar
W. F. Molina, “Chromosome changes and stasis in marine fish groups,” in Fish Cytogenetics, E. Pisano, C. Ozouf-Costaz, F. Foresti, and B. G. Kapoor, Eds., vol. 1, pp. 69–110, Science Publisher, 2007.
View at: Google Scholar
K. Ocalewicz, M. Jankun, and M. Luczynski, “Cytogenetic characteristics of interespecific hybrids and chromosome set manipulated finfish,” in Fish Cytogenetics, E. Pisano, C. Ozouf-Costaz, F. Foresti, and B. G. Kapoor, Eds., pp. 289–332, Science Publisher, 2007.
View at: Google Scholar
J. A. Beardmore, G. C. Mair, and R. I. Lewis, “Monosex male production in finfish as exemplified by tilapia: applications, problems, and prospects,” Aquaculture, vol. 197, no. 1–4, pp. 283–301, 2001.
View at: Publisher Site | Google Scholar
M. Jankun, H. Kuzminski, and G. Furgala-Selezniow, “Cytologic ploidy determination in fish–an example of two salmonid species,” Environmental Biotechnology, vol. 3, no. 2, pp. 52–56, 2007.
View at: Google Scholar
R. H. Devlin and Y. Nagahama, “Sex determination and sex differentiation in fish: an overview of genetic, physiological, and environmental influences,” Aquaculture, vol. 208, no. 3-4, pp. 191–364, 2002.
View at: Publisher Site | Google Scholar
F. Piferrer, R. M. Cal, C. Gómez, C. Bouza, and P. Martínez, “Induction of triploidy in the turbot (Scophthalmus maximus): II. Effects of cold shock timing and induction of triploidy in a large volume of eggs,” Aquaculture, vol. 220, no. 1–4, pp. 821–831, 2003.
View at: Publisher Site | Google Scholar
S. L. Chen, Y. S. Tian, J. F. Yang et al., “Artificial gynogenesis and sex determination in half-smooth tongue sole (Cynoglossus semilaevis),” Marine Biotechnology, vol. 11, no. 2, pp. 243–251, 2009.
View at: Publisher Site | Google Scholar
M. R. M. Coimbra, K. Kobayashi, S. Koretsugu et al., “A genetic linkage map of the Japanese flounder, Paralichthys olivaceus,” Aquaculture, vol. 220, no. 1–4, pp. 203–218, 2003.
View at: Publisher Site | Google Scholar
Y. Ning, X. Liu, Z. Y. Wang, W. Guo, Y. Li, and F. Xie, “A genetic map of large yellow croaker Pseudosciaena crocea,” Aquaculture, vol. 264, no. 1–4, pp. 16–26, 2007.
View at: Publisher Site | Google Scholar
W. F. Molina, “An alternative method for mitotic stimulation in fish cytogenetics,” Chromosome Science, vol. 5, pp. 149–152, 2001.
View at: Google Scholar
L. C. Gold Jr., N. S. Shipley, and P. K. Powers, “Improved methods for working with fish chromosomes with a review of metaphase chromosome banding,” Journal of Fish Biology, vol. 37, pp. 563–575, 1990.
View at: Google Scholar
A. T. Sumner, “A simple technique for demonstrating centromeric heterochromatin,” Experimental Cell Research, vol. 75, no. 1, pp. 304–306, 1972.
View at: Google Scholar
W. M. Howell and D. A. Black, “Controlled silver-staining of nucleolus organizer regions with a protective colloidal developer: a 1-step method,” Experientia, vol. 36, no. 8, pp. 1014–1015, 1980.
View at: Publisher Site | Google Scholar
A. E. Barros e Silva and M. Guerra, “The meaning of DAPI bands observed after C-banding and FISH procedures,” Biotechnic and Histochemistry, vol. 85, no. 2, pp. 115–125, 2010.
View at: Publisher Site | Google Scholar
V. Giles, G. Thode, and M. C. Alvarez, “Early replication bands in two scorpion fishes, Scorpaena porcus and S. notata (Order Scorpaeniformes),” Cytogenetic and Cell Genetics, vol. 47, pp. 80–83, 1988.
View at: Google Scholar
C. Martins, I. A. Ferreira, C. Oliveira, F. Foresti, and P. M. Galetti Jr., “A tandemly repetitive centromeric DNA sequence of the fish Hoplias malabaricus (Characiformes: Erythrinidae) is derived from 5S rDNA,” Genetica, vol. 127, no. 1–3, pp. 133–141, 2006.
View at: Publisher Site | Google Scholar
M. B. Cioffi, C. Martins, L. Centofante, U. Jacobina, and L. A. C. Bertollo, “Chromosomal variability among allopatric populations of erythrinidae fish Hoplias malabaricus: mapping of three classes of repetitive DNAs,” Cytogenetic and Genome Research, vol. 125, no. 2, pp. 132–141, 2009.
View at: Publisher Site | Google Scholar
J. W. Ijdo, R. A. Wells, A. Baldini, and S. T. Reeders, “Improved telomere detection using a telomere repeat probe (TTAGGG)(n) generated by PCR,” Nucleic Acids Research, vol. 19, no. 17, p. 4780, 1991.
View at: Google Scholar
D. Pinkel, T. Straume, and J. W. Gray, “Cytogenetic analysis using quantitative, high-sensitivity, fluorescence hybridization,” Proceedings of the National Academy of Sciences of the United States of America, vol. 83, no. 9, pp. 2934–2938, 1986.
View at: Google Scholar
A. Levan, K. Fredga, and A. A. Sandberg, “Nomenclature for centromeric position on chromosomes,” Hereditas, vol. 52, pp. 201–220, 1964.
View at: Google Scholar
D. Diniz and P. M. Xavier, “Easy Idio,” 2006, http://geocities.yahoo.com.br/easyidio.
View at: Google Scholar
W. F. Molina and T. O. D. F. Bacurau, “Structural and numerical chromosome diversification in marine Perciformes (Priacanthidae and Gerreidae),” Cytologia, vol. 71, no. 3, pp. 237–242, 2006.
View at: Publisher Site | Google Scholar
W. C. De Araújo, P. A. Martínez, and W. F. Molina, “Mapping of ribosomal DNA by FISH, EcoRI digestion and replication bands in the cardinalfish Apogon americanus (Perciformes),” Cytologia, vol. 75, no. 1, pp. 109–117, 2010.
View at: Publisher Site | Google Scholar
W. F. Molina and P. M. Galetti Jr., “Karyotypic changes associated to the dispersive potential on Pomacentridae (Pisces, Perciformes),” Journal of Experimental Marine Biology and Ecology, vol. 309, no. 1, pp. 109–119, 2004.
View at: Publisher Site | Google Scholar
M. M. Rodrigues, S. Baroni, and L. F. De Almeida-Toledo, “Karyological characterization of four marine fish species, genera Trachinotus and Selene (Perciformes: Carangidae), from the Southeast Brazilian coast,” Cytologia, vol. 72, no. 1, pp. 95–99, 2007.
View at: Publisher Site | Google Scholar
P. M. Galetti Jr., C. T. Aguilar, and W. F. Molina, “An overview of marine fish cytogenetics,” Hydrobiologia, vol. 420, no. 1–3, pp. 55–62, 2000.
View at: Publisher Site | Google Scholar
W. F. Molina and P. M. Galetti Jr., “Early replication banding in Leporinus species (Osteichthyes, Characiformes) bearing differentiated sex chromosomes (ZW),” Genetica, vol. 130, no. 2, pp. 153–160, 2007.
View at: Publisher Site | Google Scholar
R. Allshire, “Molecular biology: RNAi and heterochromatina—a hushed-up affair,” Science, vol. 297, no. 5588, pp. 1818–1819, 2002.
View at: Publisher Site | Google Scholar
K. L. Huisinga, B. Brower-Toland, and S. C. R. Elgin, “The contradictory definitions of heterochromatin: transcription and silencing,” Chromosoma, vol. 115, no. 2, pp. 110–122, 2006.
View at: Publisher Site | Google Scholar
I. Djupedal and K. Ekwall, “Molecular biology: the paradox of silent heterochromatin,” Science, vol. 320, no. 5876, pp. 624–625, 2008.
View at: Publisher Site | Google Scholar
O. Moreira-Filho and L. A. Carlos Bertollo, “Astyanax scabripinnis (Pisces, Characidae): a species complex,” Revista Brasileira de Genetica, vol. 14, no. 2, pp. 331–357, 1991.
View at: Google Scholar
L. Sola, O. Cipelli, E. Gornung, A. R. Rossi, F. Andaloro, and D. Crosetti, “Cytogenetic characterization of the greater amberjack, Seriola dumerili (Pisces: Carangidae), by different staining techniques and fluorescence in situ hybridization,” Marine Biology, vol. 128, no. 4, pp. 573–577, 1997.
View at: Publisher Site | Google Scholar
C. Martins and P. M. Galetti Jr., “Conservative distribution of 5S rDNA loci in Schizodon (Pisces, Anostomidae) chromosomes,” Chromosome Research, vol. 8, no. 4, pp. 353–355, 2000.
View at: Publisher Site | Google Scholar
S. De Lucchini, I. Nardi, G. Barsacchi, R. Batistoni, and F. Andronico, “Molecular cytogenetics of the ribosomal (18S + 28S and 5S) DNA loci in primitive and advanced urodele amphibians,” Genome, vol. 36, no. 4, pp. 762–773, 1993.
View at: Google Scholar
H. Suzuki, S. Sakurai, and Y. Matsuda, “Rat 5S rDNA spacer sequences and chromosomal assignment of the genes to the extreme terminal region of chromosome 19,” Cytogenetics and Cell Genetics, vol. 72, no. 1, pp. 1–4, 1996.
View at: Google Scholar
A. Fujiwara, S. Abe, E. Yamaha, F. Yamazaki, and M. C. Yoshida, “Chromosomal localization and heterochromatin association of ribosomal RNA gene loci and silver-stained nucleolar organizer regions in salmonid fishes,” Chromosome Research, vol. 6, no. 6, pp. 463–471, 1998.
View at: Publisher Site | Google Scholar
F. Mazzei, L. Ghigliotti, C. Bonillo, J. P. Coutanceau, C. Ozouf-Costaz, and E. Pisano, “Chromosomal patterns of major and 5S ribosomal DNA in six icefish species (Perciformes, Notothenioidei, Channichthyidae),” Polar Biology, vol. 28, no. 1, pp. 47–55, 2004.
View at: Publisher Site | Google Scholar
M. Mantovani, L. D. Dos Santos Abel, and O. Moreira-Filho, “Conserved 5S and variable 45S rDNA chromosomal localisation revealed by FISH in Astyanax scabripinnis (Pisces, Characidae),” Genetica, vol. 123, no. 3, pp. 211–216, 2005.
View at: Publisher Site | Google Scholar
P. Ráb, M. Rábová, P. S. Economidis, and C. Triantaphyllidis, “Banded karyotype of the Greek endemic cyprinid fish, Pachychilon macedonicum,” Ichthyological Research, vol. 47, no. 1, pp. 107–110, 2000.
View at: Google Scholar
M. Rábová, P. Ráb, and C. Ozouf-Costaz, “Extensive polymorphism and chromosomal characteristics of ribosomal DNA in a loach fish, Cobitis vardarensis (Ostariophysi, Cobitidae) detected by different banding techniques and fluorescence in situ hybridization (FISH),” Genetica, vol. 111, no. 1–3, pp. 413–422, 2001.
View at: Publisher Site | Google Scholar
J. Meyne, R. L. Ratliff, and R. K. Moyzis, “Conservation of the human telomere sequence (TTAGGG)_n among vertebrates,” Proceedings of the National Academy of Sciences of the United States of America, vol. 86, no. 18, pp. 7049–7053, 1989.
View at: Google Scholar
Y. Saito, R. R. Edpalina, and S. Abe, “Isolation and characterization of salmonid telomeric and centromeric satellite DNA sequences,” Genetica, vol. 131, no. 2, pp. 157–166, 2007.
View at: Publisher Site | Google Scholar
K. M. Reed and R. B. Phillips, “Molecular cytogenetic analysis of the double-CMA chromosome of lake trout, Salvelinus namaycush,” Cytogenetics and Cell Genetics, vol. 70, no. 1-2, pp. 104–107, 1995.
View at: Google Scholar
R. B. Phillips and K. M. Reed, “Application of fluorescence in situ hybridization (FISH) techniques to fish genetics: a review,” Aquaculture, vol. 140, no. 3, pp. 197–216, 1996.
View at: Google Scholar
M. B. Cioffi and L. A. C. Bertollo, “Initial steps in XY chromosome differentiation in Hoplias malabaricus and the origin of an X₁X₂Y sex chromosome system in this fish group,” Heredity, vol. 105, pp. 554–561, 2010.
View at: Publisher Site | Google Scholar
M. B. Cioffi, C. Martins, and L. A. Bertollo, “Chromosome spreading of associated transposable elements and ribosomal DNA in the fish Erythrinus erythrinus. Implications for genome change and karyoevolution in fish,” BMC Evolutionary Biology, vol. 10, no. 1, article 271, 2010.
View at: Publisher Site | Google Scholar
S. Salvadori, A. Deiana, C. Elisabetta, G. Floridia, E. Rossi, and O. Zuffardi, “Colocalization of (TTAGGG)_n telomeric sequences and ribosomal genes in Atlantic eels,” Chromosome Research, vol. 3, no. 1, pp. 54–58, 1995.
View at: Publisher Site | Google Scholar
E. Gornung, I. Gabrielli, and L. Sola, “Localization of the (TTAGGG)_n telomeric sequence in zebrafish chromosomes,” Genome, vol. 41, no. 1, pp. 136–138, 1998.
View at: Google Scholar
V. Caputo, M. Sorice, R. Vitturi, R. Magistrelli, and E. Olmo, “Cytogenetic studies in some species of scorpaeniformes (Teleostei: Percomorpha),” Chromosome Research, vol. 6, no. 4, pp. 255–262, 1998.
View at: Publisher Site | Google Scholar
P. Slijepcevic, “Telomeres and mechanisms of Robertsonian fusion,” Chromosoma, vol. 107, no. 2, pp. 136–140, 1998.
View at: Publisher Site | Google Scholar
I. Nanda, S. Schneider-Rasp, H. Winking, and M. Schmid, “Loss of telomeric sites in the chromosomes of Mus musculus domesticus (Rodentia: Muridae) during Robertsonian rearrangements,” Chromosome Research, vol. 3, no. 7, pp. 399–409, 1995.
View at: Publisher Site | Google Scholar
L. F. De Almeida-Toledo, M. F. Z. Daniel-Silva, C. E. Lopes, and S. D. A. Toledo-Filho, “Sex chromosome evolution in fish. II. Second occurrence of an X₁X₂Y sex chromosome system in Gymnotiformes,” Chromosome Research, vol. 8, no. 4, pp. 335–340, 2000.
View at: Publisher Site | Google Scholar
G. D. Johnson, “Percoidei: development and relationships,” in Ontogeny and Systematics of Fishes, H. G. Moser et al., Ed., vol. 1, pp. 464–498, American Society of Ichthyology and Herpetology, 1984.
View at: Google Scholar
V. G. Springer and W. F. Smith-Vaniz, “Supraneural and pterygiophore insertion patterns in carangid fishes, with description of a new Eocene carangid tribe, Paratrachinotini, and a survey of anterior anal-fin pterygiophore insertion patterns in Acanthomorpha,” Bulletin of the Biological Society of Washington, no. 16, pp. 1–73, 2008.
View at: Google Scholar
V. Caputo, F. Marchegiani, and E. Olmo, “Karyotype differentiation between two species of carangid fishes, genus Trachurus (Perciformes: Carangidae),” Marine Biology, vol. 127, no. 2, pp. 193–199, 1996.
View at: Google Scholar
X. Chai, X. Li, R. Lu, and S. Clarke, “Karyotype analysis of the yellowtail kingfish Seriola lalandi lalandi (Perciformes: Carangidae) from South Australia,” Aquaculture Research, vol. 40, no. 15, pp. 1735–1741, 2009.
View at: Publisher Site | Google Scholar
D. L. Reed, K. E. Carpenter, and M. J. DeGravelle, “Molecular systematics of the Jacks (Perciformes: Carangidae) based on mitochondrial cytochrome b sequences using parsimony, likelihood, and Bayesian approaches,” Molecular Phylogenetics and Evolution, vol. 23, no. 3, pp. 513–524, 2002.
View at: Publisher Site | Google Scholar
J. G. Ditty and R. F. Shaw, “Larval development, distribution, and ecology of cobia Rachycentron canadum (Family: Rachycentridae) in the northern Gulf of Mexico,” Fishery Bulletin, vol. 90, no. 4, pp. 668–677, 1992.
View at: Google Scholar
F. Garber, W. D. Grater, K. C. Stuck, and J. S. Frank, “Characterization of the mitochondrial DNA control region of Cobia, Rachycentron canadum, from Mississippi coastal waters,” Proceedings of the Gulf and Caribbean Fisheries Institute, vol. 53, pp. 570–580, 2002.
View at: Google Scholar
L. Liu, C. Liu, and N. A. Liang, “Genetic analysis of population of cobia, Rachycentron canadum around Zhanjiang waters of South China Sea with microsatellite markers,” Journal of Tropical Oceanography, vol. 27, no. 6, pp. 57–61, 2008.
View at: Google Scholar

Copyright

Copyright © 2011 Uedson Pereira Jacobina et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

PDF Download Citation

Download other formats

Order printed copies

Views

1374

Downloads

1316

Citations