Cytogenetics of the parthenogenetic grasshopper Warramaba virgo and its bisexual relatives

Schweizer, Dieter; Mendelak, M.; White, M. J. D.; Contreras, N.

doi:10.1007/bf00285625

Cited by 69 publications

(59 citation statements)

References 15 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Thus, these results have shown that the NORs in N. cruentata possess DNA rich in GC base sequences and poor in AT base sequences. NORs are known to possess GC-rich DNA in several plants (Schweizer, 1976), invertebrates (Schweizer et al, 1983;LopezFernandez et al, 1989;Loreto & Souza, 2000), and vertebrates species (Schmid, 1980).…”

Section: Discussionmentioning

confidence: 99%

Cytogenetic analysis of the neotropical spider Nephilengys cruentata (Araneomorphae, tetragnathidae): standard staining, NORs, C-bands and base-specific fluorochromes

2005

View full text Add to dashboard Cite

The aim of this work is to characterize Nephilengys cruentata in relation to the diploid number, chromosome morphology, type of sex determination chromosome system, chromosomes bearing the Nucleolar Organizer Regions (NORs), C-banding pattern, and AT or GC repetitive sequences. The chromosome preparations were submitted to standard staining (Giemsa), NOR silver impregnation, C-banding technique, and base-specific fluorochrome staining. The analysis of the cells showed 2n = 24 and 2n = 26 chromosomes in the embryos, and 2n = 26 in the ovarian cells, being all the chromosomes acrocentric. The long arm of the pairs 1, 2 and 3 showed an extensive negative heteropycnotic area when the mitotic metaphases were stained with Giemsa. The sexual chromosomes did not show differential characteristics that allowed to distinguish them from the other chromosomes of the complement. Considering the diploid numbers found in N. cruentata and the prevalence of X 1 X 2 sex determination chromosome system in Tetragnathidae, N. cruentata seems to possess 2n = 24 = 22 + X 1 X 2 in the males, and 2n = 26 = 22 + X 1 X 1 X 2 X 2 in the females. The pairs 1, 2 and 3 showed NORs which are coincident with the negative heteropycnotic patterns. Using the C-banding technique, the pericentromeric region of the chromosomes revealed small quantity or even absence of constitutive heterochromatin, differing of the C-banding pattern described in other species of spiders. In N. cruentata the fluorochromes DAPI/ DA, DAPI/MM and CMA 3 /DA revealed that the constitutive heterochromatin is rich in AT bases and the NORs possess repetitive sequences of GC bases.Key words: chromosome, Araneae, heterochromatin, secondary constriction, Chromomycin A 3 . RESUMOAnálise citogenética da aranha neotropical Nephilengys cruentata (Araneomorphae, Tetragnathidae): coloração convencional, RONs, bandas C e fluorocromos base-específicos O objetivo deste trabalho é caracterizar Nephilengys cruentata em relação ao número diplóide, à morfologia cromossômica, ao tipo de sistema cromossômico de determinação sexual, aos cromossomos portadores de Regiões Organizadoras de Nucléolo (RONs), padrão de bandas C e seqüências AT ou GC repetitivas. As preparações cromossômicas foram submetidas à coloração convencional (Giemsa), à impregnação pelo nitrato de prata, técnica de obtenção de bandas C e à coloração com fluorocromos base-específicos. A análise das células mostrou 2n = 24 e 2n = 26 cromossomos nos embriões e 2n = 26 nas células ovarianas, sendo todos cromossomos acrocêntricos. O braço longo dos pares 1, 2 e 3 apresentou extensa região heteropicnótica negativa quando as metáfases mitóticas foram coradas com Giemsa. Os cromossomos sexuais Braz. J. Biol., 65(2): 193-202, 2005 194 ARAÚJO, D., CELLA, D. M. and BRESCOVIT, A. D.species possess the type X 1 X 2 X 3 X 4 /X 1 X 1 X 2 X 2 X 3 X 3 X 4 X 4 (Datta & Chatterjee, 1983), 5 species possess the type X 1 X 2 X 3 Y/X 1 X 1 X 2 X 2 X 3 X 3 (Maddison, 1982) and 2 species show the type X 1 X 2 Y/X 1 X 1 X 2 X 2 (Silva, 1988...

show abstract

Section: Discussionmentioning

confidence: 99%

Cytogenetic analysis of the neotropical spider Nephilengys cruentata (Araneomorphae, tetragnathidae): standard staining, NORs, C-bands and base-specific fluorochromes

2005

View full text Add to dashboard Cite

show abstract

“…they show equilocal distribution (Heitz, 1933(Heitz, , 1935. Derived models assume the concerted evolution of similar repetitive DNA sequences in equivalent chromosome arms at similar positions (Schweizer et a!., 1983;Schweizer & Loidl, 1987). A comparative study of heterochromatin distribution and heterogeneity in 10 species of acridoid grasshoppers showed the strong tendency within a given complement for the accumulation of heterochromatin with similar composition at similar sites, while different sites within a given complement usually show different compositional properties (John et a!., 1985).…”

Section: Discussionmentioning

confidence: 99%

Heterochromatin differentiation between two species of the genus Dociostaurus (Orthoptera: Acrididae)

1993

View full text Add to dashboard Cite

Dociostaurus jagoi and Dociostaurus genei are two acridoid grasshoppers which show large differences in heterochromatin content. The use of several banding techniques, including fluorochrome staining and restriction endonuclease digestion, provides further information on the characteristics of the constitutive heterochromatin regions revealed with the C-banding method. Thus both species show GC-enriched bands accompanying active nucleolar organizers which differ in location. Because of its bright response to DAPI and CMA3, the centromeric heterochromatin seems to have a bipartite nature in terms of DNA composition in D. genei, while it shows dull staining with both fluorochromes in D. jagoi. However, two endonucleases, MboI and Sau3A, extensively digest these regions in both species. The supernumerary heterochromatic segments present only in D.genei seem to be AT-rich and are extensively digested with Alul. These results reveal heterogeneity in the distinct C-banded regions which, in turn, are equilocally distributed in both chromosome complements.

show abstract

“…Testicular follicle squashes were made in ethanol and acetic acid (3:1) fixative and the chromosomes stained with 2% lacto acetic orceína. We also performed C-banding (Sumner, 1972), silver nitrate (Rufas et al, 1987) and AT/GC base pair fluorescence staining (Schweizer et al, 1983). Fluorescent in situ hybridization (FISH) was performed as described by Moscone et al (1996) using Arabidopsis thaliana 45S rDNA probes (Unfried et al, 1989;Unfried and Gruendler, 1990) nick translation labeled with bio-11-dUTP (Life Technologies) and detected with rat antibiotin antibodies (Dakopatts M0743, Dako) and tetramethyl-rhodamine isothiocyanate (TRITC) conjugated rabbit anti-rat antibodies (Dakopatts R0270, Dako).…”

Section: Methodsmentioning

confidence: 99%

Karyotype, C-and fluorescence banding pattern, NOR location and FISH study of five Scarabaeidae (Coleoptera) species

et al. 2005

View full text Add to dashboard Cite

Meiotic chromosomes obtained from members of the coleopteran subfamilies Rutelinae and Dynastinae were studied using standard and silver nitrate staining, C-banding, base-specific fluorochromes and fluorescent in situ hybridization (FISH). The study presents detailed karyotipic descripitions of three Rutelinae species (Geniates borelli, Macraspis festiva and Pelidnota pallidipennis), and two Dynastinae species (Lygirus ebenus and Strategus surinamensis hirtus) with special emphasis on the distribution and variability of constitutive heterochromatin and the nucleolar organizer region (NOR). We found that for G. borelli, P. pallidipennis, L. ebenus and S. s hirtus the karyotype was 2n = 20 (9II + Xy p ), with G. borelli, P. pallidipennis and L. ebenus showed meta-submetacentric chromosomes which gradually decreased in size. For Macraspis festiva the karyotype was 2n = 18 (8II + Xy p ). In L. ebenus we found that the NOR was located on an autosome, but in the other four species it occurred on the sex bivalents. In all five species the constitutive heterochromatin (CH) was predominantly pericentromeric while the X chromosomes were almost completely heterochomatic, although CMA 3 /DA/DAPI staining showed intra and interspecific variation in the bright fluorescence of the constitutive heterochromatin. The FISH technique showed rDNA sites on the X chromosome of the Rutelinae species.

show abstract

Cytogenetics of the parthenogenetic grasshopper Warramaba virgo and its bisexual relatives

Cited by 69 publications

References 15 publications

Cytogenetic analysis of the neotropical spider Nephilengys cruentata (Araneomorphae, tetragnathidae): standard staining, NORs, C-bands and base-specific fluorochromes

Cytogenetic analysis of the neotropical spider Nephilengys cruentata (Araneomorphae, tetragnathidae): standard staining, NORs, C-bands and base-specific fluorochromes

Heterochromatin differentiation between two species of the genus Dociostaurus (Orthoptera: Acrididae)

Karyotype, C-and fluorescence banding pattern, NOR location and FISH study of five Scarabaeidae (Coleoptera) species

Contact Info

Product

Resources

About