Download or read book Drosophila Ananassae written by Yoshiko N. Tobari and published by . This book was released on 1993 with total page 316 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Evolutionary Population Genetics of Drosophila ananassae written by Pranveer Singh and published by Springer. This book was released on 2015-10-16 with total page 117 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book introduces readers to classical population genetics and the ways in which it can be applied to practical problems, including testing for natural selection, genetic drift, genetic differentiation, population structuring, gene flow and linkage disequilibrium. It provides a comprehensive monograph on the topic, addressing the theory, applications and evolutionary deductions, which are clearly explained using experimental results. It also offers separate chapters on origin, establishment and spread of chromosomal aberrations in populations along with details of culturing, maintaining and using Drosophila ananassae (genetically unique and the most commonly used species along with D. melanogaster) for genetic research. Encompassing topics like genetics, evolution, Drosophila genetics, population genetics, population structuring, natural selection and genetic drift in considerable detail, it provides a valuable resource to undergraduate and postgraduate students, as well as researchers at all level. This book explores some fundamental questions concerning the role of natural selection and genetic drift on the degree of inversion polymorphism. India, with its wide diversity in geo-climatic conditions, provides an excellent platform to conduct such studies. The book showcases sampling records of inversion frequencies in natural Indian populations of D. ananassae that cover more than two decades. It highlights case studies in which sampling data on inversion frequencies was combined with that from earlier surveys, generating a time series that allows the evolutionary dynamics of inversion polymorphism to be explored. Such long time series are rare but nonetheless crucial for studying the evolutionary dynamics of inversion polymorphism. The population-genetic analysis discussed is unprecedented in terms of its temporal (two decades) and spatial (most regions of India covered) scale and investigates the patterns of polymorphic system in D. ananassae to see if there is any temporal divergence. It endeavors to present a holistic picture of inversion polymorphism across the country (India). Chromosomal aberrations, particularly paracentric inversions, are used as a tool for discussing population genetic studies, helping human geneticists, gynecologists and other medical professionals understand why some aberrations are fatal in humans, with affected embryos often not surviving the first trimester of pregnancy, while similar aberrations in Drosophila flies aid in their adaptation to the environmental heterogeneity across the globe.
Download or read book Studies on experimental populations of Drosophila ananassae derived from irradiated natural populations written by Thomas Gilkey Gregg and published by . This book was released on 1958 with total page 76 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Chromosomes of Drosophila Ananassae written by Berwind P.. Kaufmann and published by . This book was released on 1936 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Evolution of Drosophila Ananassae Populations from the South Pacific and Southeast Asia written by Shelly Gray Smith and published by . This book was released on 2005 with total page 84 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Population Structure Analysis of Drosophila Ananassae Using Microsatellites written by Alison T. Pearce and published by . This book was released on 2002 with total page 104 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Morphology of the Chromosomes of Drosophila Ananassae written by Berwind P.. Kaufmann and published by . This book was released on 1937 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Terminal Inversion in Drosophila Ananassae written by B.-P.. Kaufmann and published by . This book was released on 1936 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book An Analysis of the Bobbed Locus of Drosophila Ananassae written by Mary Patricia White and published by . This book was released on 1969 with total page 106 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Postzygotic Sexual Isolation Among Populations of Drosophila Ananassae and Drosophila Pallidosa from Indonesia Australia Fiji and Samoa written by Christopher John Pantazis and published by . This book was released on 2009 with total page 86 pages. Available in PDF, EPUB and Kindle. Book excerpt: "Drosophila ananassae inhabits most of the tropical and subtropical regions of the world. In contrast to D. melanogaster and D. simulans, populations of D. ananassae exhibit a distinct genetic population substructure through most of their geographic range. Studies of D. ananassae populations from Trinity Beach (Australia), Apia (YSamoa), Nadi (Fiji) and Java (Indonesia) and its sister species, D. pallidosa from Malololelei (Samoa) and Nadi (Fiji) showed significant levels of prezygotic mating discrimination. However, it is unclear whether postzygotic isolation exists, and if fitness of hybrids from matings between populations and between D. ananassae and D. pallidosa is lower than fitness of offspring from matings within populations. Such postzygotic reproductive isolation among populations of D. ananassae would indicate that the populations may be in the early stages of speciation. In this study, I determined the extent to which postzygotic reproductive barriers exist among populations of D. ananassae and D. pallidosa from Australia, Samoa, Fiji, and Indonesia. I measured hybrid sterility and hybrid inviability as components of hybrid fitness of offspring from crosses between populations of D. ananassae and D. pallidosa. I found there is measurable postzygotic isolation between D. ananassae and D. pallidosa as species, but that there little measurable postzygotic isolation among populations of italicD. ananassae."--Abstract from author supplied metadata.
Download or read book Molecular Evolution of Sex biased Genes in Drosophila Ananassae written by Sonja Grath and published by . This book was released on 2010 with total page 120 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Molecular Basis of Cold Tolerance in Drosophila Ananassae written by Annabella Königer and published by . This book was released on 2019 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Sex Differences in Recombination Rates in Drosophila Ananassae written by Mary Ann Letendre and published by . This book was released on 1992 with total page 132 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Comparison of Mitochondrial Functions of 2 Different Drosophia Species written by Hye Ji Shin and published by . This book was released on 2010 with total page 36 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Mei p22 Expression in Drosophila Melanogaster and D Ananassae Males and Females and Its Relationship to Rates of Recombination written by Mahtab Attarhaie Tehrani and published by . This book was released on 2011 with total page 29 pages. Available in PDF, EPUB and Kindle. Book excerpt: The experimental work of this thesis was designed to provide the lab with tools for quantifying rates of recombination in males and females of two Drosophila species for a broader selection project. The mei-P22 gene is known to play a major role in the meiotic recombination process in Drosophila females, through initiation of DSB formation. It was selected as a marker for recombination. Among the many species of Drosophila only one, D. ananassae, has been known to show recombination in males. Using this particular species of flies and comparing it with the well-studied D. melanogaster could provide the lab with a way to study the effects of sexual selection on rates of recombination and help test the hypothesis that sexual selection plays a role in lowering rates of recombination in males. It is also worth noting that not all strains of D. ananassae have shown male recombination. Consequently, we contacted a Dr. Muneo Matsuda in Japan, who possesses strains of D. ananassae known to have shown recombination in males, and asked him to send samples for us to use. However, due to difficulties in communicating between the labs, strict customs rules and regulations, and now the earthquake, we have been unable to obtain strains with male recombination. For the purposes of working out the techniques described here, we have used strains of D. ananassae that we obtained from the U.S. stock center. It is not known whether they have male meiotic recombination. As a necessary first step of the experiment the sequence of mei-P22 in D. melanogaster and that of its putative homolog in the D. ananassae species were identified. In order to design primers, these sequences were compared to each other to find a region of greatest homology between the two. The last 252 bp region was identified as having the highest homology between the two species and was used to design primers. Following a DNA extraction and a PCR reaction using the designed primers, the products of the PCR reaction were run on a gel, the samples were purified from the gel and sent off for sequencing. The results of DNA sequencing confirmed that the sequences of mei-P22 in both species and within all strains had a high degree of homology with those available on databases. These results allowed us to verify that the correct sequence of mei-P22 was being studied and that the designed primers were functional and ready to be used in the RT-PCR reaction. As the second main step of the experiment RNA was extracted from males and females of each species. In general, even though the RNA yields from females typically fell within an acceptable concentration range, those obtained from males were significantly lower. In order to eliminate this problem, flies were raised on yeast for a period of 4 to 6 days. Even after feeding flies on the yeast diet, the RNA yields, especially for males, did not improve substantially. As a next step, we used an alternative RNA extraction protocol that eliminated the use of QIAshredder spin columns, which were used in initial attempts. This change could potentially prevent loss of significant amounts of RNA through the use of the shredders. Despite our efforts to increase male RNA yields, even the alternative RNA extraction protocol did not seem to increase male yields significantly, although female concentrations of RNA more than doubled in some cases. Another significant step of the RNA extraction was to add a DNase treatment to the extraction procedure in order to remove any traces of DNA and thus to ensure that primers were using RNA as their template and not DNA during the following RT-PCR reactions. Unfortunately, this step does not seem to have had the expected effect, and further work is necessary to obtain DNA-free RNA extracts. In order to test whether the mei-P22 gene was expressed in males and females, the RNA samples were used in an RT-PCR reaction along with our designed primers. A crucial step of the RT-PCR experiment was to add a set of controls to the reaction to test for DNA and other sources of contamination, as well as to ensure that the reaction setup and the procedure functioned properly. After visualization of the RT-PCR results, bands were observed in both DNA contamination and in some of the negative control lanes. This was an indication that our samples and possibly some reagents were most likely contaminated. The lanes corresponding to both mei-P22 and Adh positive controls also contained secondary bands of 200 bp size that could not be explained. We suspect that this last result might have been cross contamination between primers. Even though we had verified functionality of the mei-P22 primers and that the correct sequence of the gene was being used, the results indicate the possibility of several technical errors. Given the challenges posed by the molecular biology techniques throughout the experiment and after running out of time, we were not ultimately able to test the expression patterns of males and females of the two species.
Download or read book Molecular Cloning and Initial Characterization of a TART like Sequence in Drosophila Ananassae written by Jennifer Leigh Kirkland and published by . This book was released on 2005 with total page 76 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Genetics and Evolution of Sexually Dimorphic Traits in the Drosophila Bipectinata Species Complex written by and published by . This book was released on 2009 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Drosophila ananassae and its relatives have many advantages as a model of genetic differentiation and speciation. In chapter I, I examined evolutionary relationships in the ananassae species subgroup using a multi-locus molecular data set. Analysis of Y-chromosomal and mitochondrial haplotypes suggests that these taxa represent a recent evolutionary radiation and may experience substantial gene flow. I discuss possible evolutionary histories of these species. In Chapter II, I investigated the genetic basis of color pattern variation between two allopatric subspecies of D. malerkotliana, a widespread member of the ananassae species subgroup. In D. m. malerkotliana, the last three abdominal segments are darkly pigmented in males but not in females, while in D. m. pallens both sexes lack dark pigmentation. Composite interval mapping in F2 hybrid progeny shows that this difference is largely controlled by three quantitative trait loci (QTLs) located on the 2L chromosome arm, which is homologous to the 3R of D. melanogaster (Muller element E). Using highly recombinant introgression strains produced by repeated back-crossing and phenotypic selection, we showed that these QTLs do not correspond to any of the candidate genes known to be involved in pigment patterning and synthesis in Drosophila. Drosophila males use their sex combs to grasp the females' abdomen and genitalia and to spread their wings prior to copulation. In Chapter III, to test the role of this structure in male mating success in Drosophila melanogaster, I genetically ablated the sex comb by expressing the female-specific isoform of the sex determination gene transformer in the tarsal segments of male legs. This technique does not remove the sex comb entirely, but simply restores the morphology of its constituent bristles to the ancestral condition found in Drosophila species that lack sex combs. Direct observations and differences in long-term insemination rates showed that the loss of the sex comb strongly reduces the ability of males to copulate with females. Detailed analysis of video recordings indicated that this effect is not due to changes in the males' courtship behavior.
