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Antigone Zacharopoulou - One of the best experts on this subject based on the ideXlab platform.
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the chromosomes of drosophila suzukii diptera drosophilidae detailed photographic polytene chromosomal maps and in situ hybridization data
Molecular Genetics and Genomics, 2019Co-Authors: Elena Drosopoulou, Antonios A Augustinos, Angeliki Garioupapalexiou, Eleftheria Karamoustou, Georgia Gouvi, Kostas Bourtzis, Antigone ZacharopoulouAbstract:: The spotted wing drosophila, D. suzukii, is a serious agricultural pest attacking a variety of soft fruits and vegetables. Although originating from East Asia it has recently invaded America and Europe raising major concern about its expansion potential and the consequent economic losses. Since cytogenetic information on the species is scarce, we report here the mitotic karyotype and detailed photographic maps of the salivary gland polytene chromosomes of D. suzukii. The mitotic metaphase complement contains three pairs of autosomes, one of which is dot-like, and one pair of heteromorphic (XX/XY) sex chromosomes. The salivary gland polytene complement consists of five long polytene arms, representing the two metacentric autosomes and the acrocentric X chromosome, and one very short polytene element, which corresponds to the dot-like autosome. Banding pattern as well as the most characteristic features and prominent landmarks of each polytene chromosome arm are presented and discussed. Furthermore, twelve gene markers have been mapped on the polytene chromosomes of D. suzukii by in situ hybridization. Their distribution pattern was found quite similar to that of D. melanogaster revealing conservation of synteny although the relative position within each chromosome arm for most of the genes differed significantly between D. suzukii and D. melanogaster. The chromosome information presented here is suitable for comparative cytogenetic studies and phylogenetic exploration, while it could also facilitate the assembly of the genome sequence and support the development of genetic tools for species-specific and environment-friendly biological control applications such as the sterile insect technique.
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analysis of mitotic and polytene chromosomes and photographic polytene chromosome maps in bactrocera cucurbitae diptera tephritidae
Annals of The Entomological Society of America, 2011Co-Authors: Antonios A Augustinos, Farzana Yesmin, A S Robinson, Antigone Zacharopoulou, W. A. A. Sayed, Gerald FranzAbstract:ABSTRACT We report here a cytogenetic analysis of the melon fly, Bactrocera Cucurbitae, Coquillett (Diptera: Tephritidae), a species of significant agricultural importance. The mitotic karyotype and detailed photographic maps of the larval salivary gland polytene chromosomes of the species are presented. The mitotic karyotype consists of six pairs of chromosomes including one pair of heteromorphic sex (XX/XY) chromosomes. The heterogametic sex is ascribed to the male. The analysis of polytene chromosomes has shown a total number of five long polytene elements (10 polytene arms) that correspond to the five autosomes. The characteristic features and the most prominent landmarks of each polytene chromosome are presented. The proposed chromosomal homology between B. Cucurbitae and Mediterranean fruit fly, Ceratitis capitata (Wiedemann), was determined by comparing chromosome banding patterns. The detection of heterozygous chromosome inversions in two strains is shown and discussed. The current study provides ...
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mitotic and polytene chromosomes analysis of the oriental fruit fly bactrocera dorsalis hendel diptera tephritidae
Genetica, 2011Co-Authors: Antigone Zacharopoulou, Antonios A Augustinos, A S Robinson, W. A. A. Sayed, Gerald FranzAbstract:The Oriental fruit fly, Batrocera dorsalis s.s. (Hendel) is one of the most destructive agricultural pests, belonging to a large group of difficult to distinguish morphologically species, referred as the B. dorsalis complex. We report here a cytogenetic analysis of two laboratory strains of the species and provide a photographic polytene chromosome map from larval salivary glands. The mitotic complement consists of six chromosome pairs including a heteromorphic sex (XX/XY) chromosome pair. Analysis of the polytene complement has shown a total of five polytene chromosomes (10 polytene arms) that correspond to the five autosomes. The most important landmarks of each polytene chromosome and characteristic asynapsis at a specific chromosomal region are presented and discussed. Chromosomal homology between B. dorsalis and Ceratitis capitata has been determined by comparing chromosome banding patterns. The detection of chromosome inversions in both B. dorsalis strains is shown and discussed. Our results show that the polytene maps presented here are suitable for cytogenetic analysis of this species and can be used for comparative studies among species of the Tephritidae family. They also provide a diagnostic tool that could accelerate species identification within the B. dorsalis complex and could shed light on the ongoing speciation in this complex. Polytene chromosome maps can facilitate the development of biological control methods and support the genome mapping project of the species that is currently in progress.
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mitotic and polytene chromosome analysis in the mexican fruit fly anastrepha ludens loew diptera tephritidae
Genome, 2009Co-Authors: E Hernandezortiz, C S Zepetacisneros, A S Robinson, Antigone Zacharopoulou, Virginia GarciamartinezAbstract:The present study constitutes the first attempt to construct a polytene chromosome map of an Anastrepha species, Anastrepha ludens (Loew), a major agricultural pest. The mitotic karyotype has a diploid complement of 12 acrocentric chromosomes, including five pairs of autosomes and an XX/XY sex chromosome pair. The analysis of salivary gland polytene chromosomes has shown a total number of five polytene elements that correspond to the five autosomes. The characteristic features and the most prominent landmarks of each chromosome are described. By comparing chromosome banding patterns, the possible chromosomal homology between A. ludens and Ceratitis capitata (Wiedemann) is presented. This work shows that polytene maps of A. ludens are suitable for cytogenetic studies in this species and may be used as reference for other Anastrepha species, most of which are also serious agricultural pests.
Eungsoo Kim - One of the best experts on this subject based on the ideXlab platform.
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carboxyl terminal domain characterization of polyene specific p450 hydroxylase in pseudonocardia autotrophica
Journal of Industrial Microbiology & Biotechnology, 2016Co-Authors: Minkyung Kim, Hyungjin Won, Hyejin Kim, Sisun Choi, Heungshick Lee, Pil Kim, Eungsoo KimAbstract:A polyene compound NPP identified in Pseudonocardia autotrophica was shown to contain an aglycone identical to nystatin, but to harbor a unique disaccharide moiety that led to higher solubility and reduced hemolytic activity. Recently, it was revealed that the final step of NPP (nystatin-like polyene) biosynthesis is C10 regio-specific hydroxylation by the cytochrome P450 hydroxylase (CYP) NppL (Kim et al. [7]). Through mutation and cross-complementation, here we found that NppL preferred a polyene substrate containing a disaccharide moiety for C10 hydroxylation, while its orthologue NysL involved in nystatin biosynthesis showed no substrate preference toward mono- and disaccharide moieties, suggesting that two homologous polyene CYPs, NppL and NysL might possess a unique domain recognizing a sugar moiety. Two hybrid NppL constructs containing the C-terminal domain of NysL exhibited no substrate preference toward 10-deoxy NPP and 10-deoxy nystatin-like NysL, implying that the C-terminal domain plays a major role in differentiating the sugar moiety responsible for substrate specificity. Further C-terminal domain dissection of NppL revealed that the last fifty amino acids play a critical role in determining substrate specificity of polyene-specific hydroxylation, setting the stage for the biotechnological application of hydroxyl diversification for novel polyene biosynthesis in actinomycetes.
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identification of functionally clustered nystatin like biosynthetic genes in a rare actinomycetes pseudonocardia autotrophica
Journal of Industrial Microbiology & Biotechnology, 2009Co-Authors: Byung Gyun Kim, Miyeon Lee, Mi Jin Lee, Jiyoon Seo, Young Bin Hwang, Kyuboen Han, David H Sherman, Eungsoo KimAbstract:The polyene antibiotics, including nystatin, pimaricin, amphotericin, and candicidin, comprise a family of very valuable antifungal polyketide compounds, and they are typically produced by soil actinomycetes. Previously, using a polyene cytochrome P450 hydroxylase-specific genome screening strategy, Pseudonocardia autotrophica KCTC9441 was determined to contain genes potentially encoding polyene biosynthesis. Here, sequence information of an approximately 125.7-kb contiguous DNA region in five overlapping cosmids isolated from the P. autotrophica KCTC9441 genomic library revealed a total of 23 open reading frames, which are presumably involved in the biosynthesis of a nystatin-like compound tentatively named NPP. The deduced roles for six multi-modular polyketide synthase (PKS) catalytic domains were found to be highly homologous to those of previously identified nystatin biosynthetic genes. Low NPP productivity suggests that the functionally clustered NPP biosynthetic pathway genes are tightly regulated in P. autotrophica. Disruption of a NPP PKS gene completely abolished both NPP biosynthesis and antifungal activity against Candida albicans, suggesting that polyene-specific genome screening may constitute an efficient method for isolation of potentially valuable previously identified polyene genes and compounds from various rare actinomycetes widespread in nature.
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isolation and partial characterization of a cryptic polyene gene cluster in pseudonocardia autotrophica
Journal of Industrial Microbiology & Biotechnology, 2006Co-Authors: Miyeon Lee, Ji Seon Myeong, Hyunjoo Park, Kyuboem Han, Eungsoo KimAbstract:The polyene antibiotics, a category that includes nystatin, pimaricin, amphotericin, and candicidin, comprise a family of very promising antifungal polyketide compounds and are typically produced by soil actinomycetes. The biosynthetic gene clusters for these polyenes have been previously investigated, revealing the presence of highly similar cytochrome P450 hydroxylase (CYP) genes. Using polyene CYP-specific PCR screening with several actinomycete genomic DNAs, Pseudonocardia autotrophica was determined to contain a unique polyene-specific CYP gene. Genomic DNA library screening using the polyene-specific CYP gene probe identified a positive cosmid clone, which contained a DNA fragment of approximately 34.5 kb. The complete sequencing of this DNA fragment revealed a total of seven complete and two incomplete open reading frames, which were found to be highly similar, but still unique, when compared to previously known polyene biosynthetic genes. These results suggest that the polyene-specific screening approach may constitute an efficient method for the isolation of potentially valuable cryptic polyene biosynthetic gene clusters from various rare actinomycetes.
T D Kolesnikova - One of the best experts on this subject based on the ideXlab platform.
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replication timing in drosophila and its peculiarities in polytene chromosomes
Journal of Genetics and Breeding, 2019Co-Authors: T D Kolesnikova, O V Antonenko, Igor V MakuninAbstract:Drosophila melanogaster is one of the popular model organisms in DNA replication studies. Since the 1960s, DNA replication of polytene chromosomes has been extensively studied by cytological methods. In the recent two decades, the progress in our understanding of DNA replication was associated with new techniques. Use of fluorescent dyes increased the resolution of cytological methods significantly. High-throughput methods allowed analysis of DNA replication on a genome scale, as well as its correlation with chromatin structure and gene activity. Precise mapping of the cytological structures of polytene chromosomes to the genome assembly allowed comparison of replication between polytene chromosomes and chromosomes of diploid cells. New features of replication characteristic for D. melanogaster were described for both diploid and polytene chromosomes. Comparison of genomic replication profiles revealed a significant similarity between Drosophila and other well-studied eukaryotic species, such as human. Early replication is often confined to intensely transcribed gene-dense regions characterized by multiple replication initiation sites. Features of DNA replication in Drosophila might be explained by a compact genome. The organization of replication in polytene chromosomes has much in common with the organization of replication in chromosomes in diploid cells. The most important feature of replication in polytene chromosomes is its low rate and the dependence of S-phase duration on many factors: external and internal, local and global. The speed of replication forks in D. melanogaster polytene chromosomes is affected by SUUR and Rift proteins. It is not known yet how universal the mechanisms associated with these factors are, but their study is very promising.
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banding pattern of polytene chromosomes as a representation of universal principles of chromatin organization into topological domains
Biochemistry, 2018Co-Authors: T D KolesnikovaAbstract:: Drosophila polytene chromosomes are widely used as a model of eukaryotic interphase chromosomes. The most noticeable feature of polytene chromosome is transverse banding associated with alternation of dense stripes (dark or black bands) and light diffuse areas that encompass alternating less compact gray bands and interbands visible with an electron microscope. In recent years, several approaches have been developed to predict location of morphological structures of polytene chromosomes based on the distribution of proteins on the molecular map of Drosophila genome. Comparison of these structures with the results of analysis of the three-dimensional chromatin organization by the Hi-C method indicates that the morphology of polytene chromosomes represents direct visualization of the interphase nucleus spatial organization into topological domains. Compact black bands correspond to the extended topological domains of inactive chromatin, while interbands are the barriers between the adjacent domains. Here, we discuss the prospects of using polytene chromosomes to study mechanisms of spatial organization of interphase chromosomes, as well as their dynamics and evolution.
Lin Tingtin - One of the best experts on this subject based on the ideXlab platform.
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genetic analysis of chlorophyll content using mixed major gene plus Polygene inheritance model in non heading chinese cabbage
Journal of Nanjing Agricultural University, 2014Co-Authors: Lin TingtinAbstract:Chlorophyll plays a fundamental role in the energy absorption and transduction activities of photosynthetic organisms,and is essential in growth and production of vegetable crops.However,little is known on the genetic model of chlorophyll content.Here,we performed genetic analysis of chlorophyll content in non-heading Chinese cabbage( Brassica campestris ssp.chinensis Makino),and the results could contribute to the illustration for chlorophyll genetic model and exploration of new genes involving in regulation of chlorophyll content.Two cultivars of non-heading Chinese cabbage,‘Wutacai'with high chlorophyll content and‘Erqing'with low chlorophyll content,were selected in this genetic analysis.Six generations( P1,P2,F1,B1,B2 and F2) were achieved by hybridization and backcross.Chlorophyll contents of all plants were detected by SPAD-502 Plus Chlorophyll Meter.The mixed major genes plus Polygene inheritance model were used for the genetic analysis of chlorophyll content.The results of two years( 2011 and 2013) both showed that differences of chlorophyll contents between parents P1 and P2were extremely significant,while chlorophyll levels of F1 population distributed between P1 and P2,and were closer to P1.The trait of chlorophyll content in non-heading Chinese cabbage was controlled by the model of one additive-dominant major gene plus additive-dominant-epitasis Polygene.Results of 2011 in plastic tunnel and 2013 in open field showed that the additive effects of major genes were 9.59 and 4.48,respectively.The dominant effects of two years were 1.17 and 2.09,respectively.In 2011,the heritabilities of major genes in the B1,B2 and F2populations were 22.86%,41.65% and 61.24%,respectively,and those of Polygenes were 59.18%,36.08% and 24.30%,respectively.In 2013,the heritabilities of major genes in the B1,B2 and F2 populations were 5.66%,38.51% and 26.29%,respectively,and those of Polygenes were 64.99%,22.93% and 52.08%,respectively.Results of two years showed that environments had significant influence on the hereditary of chlorophyll content in non-heading Chinese cabbage.The environment variance in 2011 and 2013 was 14.46% and 21.63%,respectively.Conclusion: The trait of chlorophyll content in non-heading Chinese cabbage was controlled by one additive-dominant major gene plus additive-dominant-epitasis Polygene,and environmental factors play roles in the hereditary of chloro-phyll content,which should be considered in the breeding process.A single directional selection or recurrent selection method could be used during cultivars improvements of non-heading Chinese cabbage,and the marker assisted selection method should be taken for production of high chlorophyll content lines.
Igor F. Zhimulev - One of the best experts on this subject based on the ideXlab platform.
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polytene chromosomes 70 years of genetic research
International Review of Cytology-a Survey of Cell Biology, 2004Co-Authors: Igor F. Zhimulev, Olga V Demakova, S A Demakov, Elena S. Belyaeva, Galina V. Pokholkova, Valeriy F Semeshin, Dmitry E. Koryakov, Evgeniya N AndreyevaAbstract:Polytene chromosomes were described in 1881 and since 1934 they have served as an outstanding model for a variety of genetic experiments. Using the polytene chromosomes, numerous biological phenomena were discovered. First the polytene chromosomes served as a model of the interphase chromosomes in general. In polytene chromosomes, condensed (bands), decondensed (interbands), genetically active (puffs), and silent (pericentric and intercalary heterochromatin as well as regions subject to position effect variegation) regions were found and their features were described in detail. Analysis of the general organization of replication and transcription at the cytological level has become possible using polytene chromosomes. In studies of sequential puff formation it was found for the first time that the steroid hormone (ecdysone) exerts its action through gene activation, and that the process of gene activation upon ecdysone proceeds as a cascade. Namely on the polytene chromosomes a new phenomenon of cellular stress response (heat shock) was discovered. Subsequently chromatin boundaries (insulators) were discovered to flank the heat shock puffs. Major progress in solving the problems of dosage compensation and postion effect variegation phenomena was mainly related to studies on polytene chromosomes. This review summarizes the current status of studies of polytene chromosomes and of various phenomena described using this successful model.
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use of immunogold labelling technique for immunoelectron microscope localization of proteins in drosophila polytene chromosomes
Tsitologiia, 2003Co-Authors: Valeriy F Semeshin, Harald Saumweber, V V Shloma, E N Andreeva, Igor F. ZhimulevAbstract:Using gold labeled antibodies, we developed and tested an immunoelectron microscope (IEM) method for detection of protein localization in Drosophila melanogaster polytene chromosomes. This method is based on procedures widely used for indirect immunofluorescent (IF) staining of salivary gland polytene chromosome squashes. The application of IEM was evaluated by using specific antibodies against proteins earlier localized in both decondensed (interbands and puffs) and compact (bands) regions of polytene chromosomes. In all the experiments, IEM and IF images for homologous chromosome regions were compared. When applied to regions of loose structures, IEM enabled us to localize, with high precision, signals in fine bands, interbands and puffs. There was a good correspondence between immunogold EM and IF data. However, there was no correspondence for dense bands: gold particles were distributed at their boundaries, while the entire bands showed bright fluorescence. This discrepancy probably resulted from a poor penetration of antibodies conjugated to gold particles in the tightly packaged structures. From the results obtained it may by concluded that the IEM method is advantageous for studying the fine protein topography of loose decompacted regions of polytene chromosomes. And this must be taken into consideration when protein localization in polytene chromosomes is performed.
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morphology and structure of polytene chromosomes
Advances in Genetics, 1996Co-Authors: Igor F. ZhimulevAbstract:Publisher Summary This chapter reviews the morphology and structure of polytene chromosomes. The chapter focuses on the gene mapping and building of cytogenetic maps, as well as on problems pertaining to the genetic organization of the main morphological structures of polytene chromosomes—the chromomeres and interchromomeric regions. Subsequently, there is a set of models for the genetic organization of chromomeres in which the chromomere and its adjacent interband are viewed as a single genetic unit. Polytene, that is, multifibered chromosomes with high polyteny level, have been found in many tissues of the representatives of four orders of insects—Diptera, Collembola, Lepidoptera, and Orthoptera, in the macronuclear anlagen of infusoria, in certain organs and tissues of mammals, and also in the cells of the synergids, antipods, haustoria, and endosperm of angiospermous plants. The polyteny has an adaptive significance, endoploidy is the physiological basis of polyteny, and homologous chromosome pairing expressed to different degrees is its structural basis. Because the two events are rather widespread, the occurrence of various forms of polytene chromosomes in actively functioning giant cells of many species may be expected.
