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Maria Tercilia Vilela De Azeredooliveira - One of the best experts on this subject based on the ideXlab platform.
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molecular cytotaxonomy of the triatoma brasiliensis species subcomplex hemiptera triatominae
Acta Tropica, 2020Co-Authors: Kaio Cesar Chaboli Alevi, Joao Aristeu Da Rosa, Isadora De Freitas Bittinelli, Luiza Maria Grzyb Delgado, Fernanda Fernandez Madeira, Jader De Oliveira, Mauricio Lilioso, Elaine Follyramos, Maria Tercilia Vilela De AzeredooliveiraAbstract:Abstract The Triatoma genus is paraphyletic, and its species are grouped into complexes and subcomplexes. Given the fact that species that make up a given subcomplex generally share chromosomal traits, we analyzed the distribution of AT- and CG-rich DNA of the T. brasiliensis species subcomplex, in order to establish affinities among members of the T. brasiliensis subcomplex based on chromatin and chromosome traits and develop an identification key for the four monophyletic Triatoma subcomplexes from South America. All species exhibited a CG-rich X sex chromosome and autosomes, as well as an AT-rich Y sex chromosome. This feature can be used as a diagnostic characteristic to determine whether a given species is a member of the T. brasiliensis subcomplex, because it enables the differentiation of these species from all Triatoma of South America. Thus, we confirmed the chromosomal relationship of the T. brasiliensis species subcomplex and developed a dichotomous key based on the chromocenter to differentiate the species from this subcomplex from the other monophyletic Triatoma subcomplexes from South America.
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description of the diploid chromosome set of triatoma pintodiasi hemiptera triatominae
Genetics and Molecular Research, 2016Co-Authors: Kaio Cesar Chaboli Alevi, Felipe Ferraz Figueiredo Moreira, Jose Jurberg, Maria Tercilia Vilela De AzeredooliveiraAbstract:Triatoma pintodiasi has been described and recently grouped in the Rubrovaria subcomplex. T. pintodiasi was initially compared to T. carcavalloi by staining and subsequently identified as T. circummaculata. However, after thorough examination, it was observed to be a cryptic species of T. circummaculata, and was described based on morphological features, morphometric data, and biochemical patterns of hemolymph. Thus, this paper aims to describe the karyotype of, and spermatogenesis in, T. pintodiasi, in order to elucidate the reproductive biology and taxonomy of the species. Sex chromosomes of T. pintodiasi formed a heteropyknotic chromocenter, and compaction of chromatin was observed during prophase. However, in contrast to observations in T. carcavalloi and T. circummaculata, in T. pintodiasi it was observed individualization of the sex chromosomes. The diploid chromosome set of the species 2n = 22 (20A + XY) is described through analysis of metaphases I and II. Initial cytogenetic characteristics of T. pintodiasi are described and the observed differences in the chromocenter are suggested as a possible cytotaxonomic tool. To gain a better understanding of the specific status of this cryptic species, however, we emphasize the need for further cytogenetic, molecular, biological, and biogeographical analysis, in addition to experimental hybrid crosses with other species of the Rubrovaria subcomplex.
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spermatogenesis in triatoma melanocephala hemiptera triatominae
Genetics and Molecular Research, 2013Co-Authors: Kaio Cesar Chaboli Alevi, Priscila Pasquetto Mendonca, Nathalia Paiva Pereira, Joao Aristeu Da Rosa, Maria Tercilia Vilela De AzeredooliveiraAbstract:Triatoma melanocephala is a rare species of Hemiptera. It belonged to the Brasiliensis subcomplex and presents morphological characteristics very close to those of Triatoma vitticeps. We investigated spermatogenesis of T. melanocephala and compared it with that of T. vitticeps in order to determine whether these organisms have similar cytogenetic characteristics. Lacto-acetic orcein staining was used to observe all stages of meiosis. These two species were found to have the same karyotype (2n = 20A + X1X2X3Y), heteropycnotic corpuscles in the polyploid spermatogonial cells, interfasic and profasic nucleus, and chromocenter with four sex chromosomes during prophase. Thus, we conclude that besides the morphologic similarity of T. melanocephala with T. vitticeps, they also have similar spermatogenesis and cytogenetics.
Kaio Cesar Chaboli Alevi - One of the best experts on this subject based on the ideXlab platform.
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molecular cytotaxonomy of the triatoma brasiliensis species subcomplex hemiptera triatominae
Acta Tropica, 2020Co-Authors: Kaio Cesar Chaboli Alevi, Joao Aristeu Da Rosa, Isadora De Freitas Bittinelli, Luiza Maria Grzyb Delgado, Fernanda Fernandez Madeira, Jader De Oliveira, Mauricio Lilioso, Elaine Follyramos, Maria Tercilia Vilela De AzeredooliveiraAbstract:Abstract The Triatoma genus is paraphyletic, and its species are grouped into complexes and subcomplexes. Given the fact that species that make up a given subcomplex generally share chromosomal traits, we analyzed the distribution of AT- and CG-rich DNA of the T. brasiliensis species subcomplex, in order to establish affinities among members of the T. brasiliensis subcomplex based on chromatin and chromosome traits and develop an identification key for the four monophyletic Triatoma subcomplexes from South America. All species exhibited a CG-rich X sex chromosome and autosomes, as well as an AT-rich Y sex chromosome. This feature can be used as a diagnostic characteristic to determine whether a given species is a member of the T. brasiliensis subcomplex, because it enables the differentiation of these species from all Triatoma of South America. Thus, we confirmed the chromosomal relationship of the T. brasiliensis species subcomplex and developed a dichotomous key based on the chromocenter to differentiate the species from this subcomplex from the other monophyletic Triatoma subcomplexes from South America.
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description of the diploid chromosome set of triatoma pintodiasi hemiptera triatominae
Genetics and Molecular Research, 2016Co-Authors: Kaio Cesar Chaboli Alevi, Felipe Ferraz Figueiredo Moreira, Jose Jurberg, Maria Tercilia Vilela De AzeredooliveiraAbstract:Triatoma pintodiasi has been described and recently grouped in the Rubrovaria subcomplex. T. pintodiasi was initially compared to T. carcavalloi by staining and subsequently identified as T. circummaculata. However, after thorough examination, it was observed to be a cryptic species of T. circummaculata, and was described based on morphological features, morphometric data, and biochemical patterns of hemolymph. Thus, this paper aims to describe the karyotype of, and spermatogenesis in, T. pintodiasi, in order to elucidate the reproductive biology and taxonomy of the species. Sex chromosomes of T. pintodiasi formed a heteropyknotic chromocenter, and compaction of chromatin was observed during prophase. However, in contrast to observations in T. carcavalloi and T. circummaculata, in T. pintodiasi it was observed individualization of the sex chromosomes. The diploid chromosome set of the species 2n = 22 (20A + XY) is described through analysis of metaphases I and II. Initial cytogenetic characteristics of T. pintodiasi are described and the observed differences in the chromocenter are suggested as a possible cytotaxonomic tool. To gain a better understanding of the specific status of this cryptic species, however, we emphasize the need for further cytogenetic, molecular, biological, and biogeographical analysis, in addition to experimental hybrid crosses with other species of the Rubrovaria subcomplex.
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spermatogenesis in triatoma melanocephala hemiptera triatominae
Genetics and Molecular Research, 2013Co-Authors: Kaio Cesar Chaboli Alevi, Priscila Pasquetto Mendonca, Nathalia Paiva Pereira, Joao Aristeu Da Rosa, Maria Tercilia Vilela De AzeredooliveiraAbstract:Triatoma melanocephala is a rare species of Hemiptera. It belonged to the Brasiliensis subcomplex and presents morphological characteristics very close to those of Triatoma vitticeps. We investigated spermatogenesis of T. melanocephala and compared it with that of T. vitticeps in order to determine whether these organisms have similar cytogenetic characteristics. Lacto-acetic orcein staining was used to observe all stages of meiosis. These two species were found to have the same karyotype (2n = 20A + X1X2X3Y), heteropycnotic corpuscles in the polyploid spermatogonial cells, interfasic and profasic nucleus, and chromocenter with four sex chromosomes during prophase. Thus, we conclude that besides the morphologic similarity of T. melanocephala with T. vitticeps, they also have similar spermatogenesis and cytogenetics.
Dmitry E Koryakov - One of the best experts on this subject based on the ideXlab platform.
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the suur gene influences the distribution of heterochromatic proteins hp1 and su var 3 9 on nurse cell polytene chromosomes of drosophila melanogaster
Chromosoma, 2006Co-Authors: Gunter Reuter, Dmitry E Koryakov, Patrizio Dimitri, I F ZhimulevAbstract:We have investigated the distribution of three heterochromatic proteins [SUppressor of UnderReplication (SUUR), heterochromatin protein 1 (HP1), and SU(VAR)3–9] in chromosomes of nurse cells (NCs) and have compared the data obtained with the distribution of the same proteins in salivary gland (SG) chromosomes. In NC chromosomes, the SU(VAR)3–9 protein was found in pericentric heterochromatin and at 223 sites on euchromatic arms, while in SG chromosomes, it was mainly restricted to the chromocenter. In NC chromosomes, the HP1 and SUUR proteins bind to 331 and 256 sites, respectively, which are almost twice the number of sites in SG chromosomes. The distribution of the HP1 and SU(VAR)3–9 proteins depends on the SuUR gene. A mutation in this gene results in a dramatic decrease in the amount of SU(VAR)3–9 binding sites in autosomes. In the X chromosome, these sites are relocated in comparison to the SuUR +, and their total number only varies slightly. HP1 binding sites are redistributed in chromosomes of SuUR mutants, and their overall number did not change as considerably as SU(VAR)3–9. These data together point to an interaction of these three proteins in Drosophila NC chromosomes.
Joao Aristeu Da Rosa - One of the best experts on this subject based on the ideXlab platform.
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molecular cytotaxonomy of the triatoma brasiliensis species subcomplex hemiptera triatominae
Acta Tropica, 2020Co-Authors: Kaio Cesar Chaboli Alevi, Joao Aristeu Da Rosa, Isadora De Freitas Bittinelli, Luiza Maria Grzyb Delgado, Fernanda Fernandez Madeira, Jader De Oliveira, Mauricio Lilioso, Elaine Follyramos, Maria Tercilia Vilela De AzeredooliveiraAbstract:Abstract The Triatoma genus is paraphyletic, and its species are grouped into complexes and subcomplexes. Given the fact that species that make up a given subcomplex generally share chromosomal traits, we analyzed the distribution of AT- and CG-rich DNA of the T. brasiliensis species subcomplex, in order to establish affinities among members of the T. brasiliensis subcomplex based on chromatin and chromosome traits and develop an identification key for the four monophyletic Triatoma subcomplexes from South America. All species exhibited a CG-rich X sex chromosome and autosomes, as well as an AT-rich Y sex chromosome. This feature can be used as a diagnostic characteristic to determine whether a given species is a member of the T. brasiliensis subcomplex, because it enables the differentiation of these species from all Triatoma of South America. Thus, we confirmed the chromosomal relationship of the T. brasiliensis species subcomplex and developed a dichotomous key based on the chromocenter to differentiate the species from this subcomplex from the other monophyletic Triatoma subcomplexes from South America.
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spermatogenesis in triatoma melanocephala hemiptera triatominae
Genetics and Molecular Research, 2013Co-Authors: Kaio Cesar Chaboli Alevi, Priscila Pasquetto Mendonca, Nathalia Paiva Pereira, Joao Aristeu Da Rosa, Maria Tercilia Vilela De AzeredooliveiraAbstract:Triatoma melanocephala is a rare species of Hemiptera. It belonged to the Brasiliensis subcomplex and presents morphological characteristics very close to those of Triatoma vitticeps. We investigated spermatogenesis of T. melanocephala and compared it with that of T. vitticeps in order to determine whether these organisms have similar cytogenetic characteristics. Lacto-acetic orcein staining was used to observe all stages of meiosis. These two species were found to have the same karyotype (2n = 20A + X1X2X3Y), heteropycnotic corpuscles in the polyploid spermatogonial cells, interfasic and profasic nucleus, and chromocenter with four sex chromosomes during prophase. Thus, we conclude that besides the morphologic similarity of T. melanocephala with T. vitticeps, they also have similar spermatogenesis and cytogenetics.
Pierre Spierer - One of the best experts on this subject based on the ideXlab platform.
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loss of the modifiers of variegation su var 3 7 or hp1 impacts male x polytene chromosome morphology and dosage compensation
Journal of Cell Science, 2005Co-Authors: Anne Spierer, Carole Seum, Marion Delattre, Pierre SpiererAbstract:Loss of Su(var)3-7 or HP1 suppresses the genomic silencing of position-effect variegation, whereas over-expression enhances it. In addition, loss of Su(var)3-7 results in preferential male lethality. In polytene chromosomes deprived of Su(var)3-7, we observe a specific bloating of the male X chromosome, leading to shortening of the chromosome and to blurring of its banding pattern. In addition, the chromocenter, where heterochromatin from all polytene chromosomes fuses, appears decondensed. The same chromosomal phenotypes are observed as a result of loss of HP1. Mutations of Su(var)3-7 or of Su(var)2-5, the gene encoding HP1, also cause developmental defects, including a spectacular increase in size of the prothoracic gland and its polytene chromosomes. Thus, although structurally very different, the two proteins cooperate closely in chromosome organization and development. Finally, bloating of the male X chromosome in the Su(var)3-7 mutant depends on the presence of a functional dosage compensation complex on this chromosome. This observation reveals a new and intriguing genetic interaction between epigenetic silencing and compensation of dose.