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Genomes and Genes | S W SchaefferSummaryAffiliation: Pennsylvania State University Country: USA Publications
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Publications
Polytene chromosomal maps of 11 Drosophila species: the order of genomic scaffolds inferred from genetic and physical mapsStephen W Schaeffer
Department of Biology and Institute of Molecular Evolutionary Genetics, The Pennsylvania State University, University Park, Pennsylvania 16802, USA
Genetics 179:1601-55. 2008..Despite the conservation of genes within homologous chromosome arms across species, the karyotypes of these species have changed through the fusion of chromosomal arms followed by subsequent rearrangement events...- Protein variation in Adh and Adh-related in Drosophila pseudoobscura. Linkage disequilibrium between single nucleotide polymorphisms and protein allelesS W Schaeffer
Department of Biology, The Pennsylvania State University, University Park, Pennsylvania 16802, USA
Genetics 159:673-87. 2001..The implication of this study is that linkage disequilibrium mapping has the highest probability of success with disease-causing alleles at frequencies of 10%... - Evolutionary rearrangement of the amylase genomic regions between Drosophila melanogaster and Drosophila pseudoobscuraS W Schaeffer
Department of Biology and Institute of Molecular Evolutionary Genetics, Pennsylvania State University, 208 Erwin W Mueller Laboratory, University Park, PA 16802 5301, USA
J Hered 94:464-71. 2003..melanogaster or D. pseudoobscura lineage. The predicted genes within the 73A and 78C regions show patterns of molecular evolution in synonymous and nonsynonymous sites that are consistent with previous studies of these two species... - Evolutionary genomics of inversions in Drosophila pseudoobscura: evidence for epistasisStephen W Schaeffer
Department of Biology and Institute of Molecular Evolutionary Genetics, Pennsylvania State University, University Park, PA 16802 5301, USA
Proc Natl Acad Sci U S A 100:8319-24. 2003..pseudoobscura have emerged as suppressors of recombination to maintain positive epistatic relationships among loci within gene arrangements that developed as the species adapted to a heterogeneous environment... - Molecular population genetics of sequence length diversity in the Adh region of Drosophila pseudoobscuraStephen W Schaeffer
Department of Biology, and Institute of Molecular Evolutionary Genetics, The Pennsylvania State University, University Park, PA 16802 5301, USA
Genet Res 80:163-75. 2002..Genome rearrangement and size-dependent intron evolution are proposed as mechanisms that limit runaway intron expansion... - Selection in heterogeneous environments maintains the gene arrangement polymorphism of Drosophila pseudoobscuraStephen W Schaeffer
Department of Biology and Institute of Molecular Evolutionary Genetics, The Pennsylvania State University, University Park, Pennsylvania 16802, USA
Evolution 62:3082-99. 2008..pseudoobscura gene arrangement polymorphism. Models of local adaptation predict that the new inversion mutations were able to invade populations because they held combinations of two to 13 local adaptation loci together... - Mechanisms of genetic exchange within the chromosomal inversions of Drosophila pseudoobscuraStephen W Schaeffer
Department of Biology and Institute of Molecular Evolutionary Genetics, Pennsylvania State University, 208 Erwin W Mueller Laboratories, University Park, PA 16802 5301, USA
Genetics 171:1729-39. 2005..At least one case where selection rather than proximity to an inversion breakpoint is responsible for reduction in polymorphism was identified... - Molecular population genetics of X-linked genes in Drosophila pseudoobscuraM Kovacevic
Department of Biology and Institute of Molecular Evolutionary Genetics, The Pennsylvania State University, University Park, Pennsylvania 16802 5301, USA
Genetics 156:155-72. 2000..The reduced heterogeneity in esterase 5 is due either to its location near one of the Sex-ratio inversion breakpoints or that it is closely linked to a gene or genes responsible for the Sex-ratio meiotic drive system... - Estimates of linkage disequilibrium and the recombination parameter determined from segregating nucleotide sites in the alcohol dehydrogenase region of Drosophila pseudoobscuraS W Schaeffer
Department of Biology, Pennsylvania State University, University Park 16802
Genetics 135:541-52. 1993..The most likely explanation for the two clusters of linkage disequilibria is epistatic selection between sites in the cluster to maintain pre-mRNA secondary structure... - Estimates of gene flow in Drosophila pseudoobscura determined from nucleotide sequence analysis of the alcohol dehydrogenase regionS W Schaeffer
Department of Biology, Pennsylvania State University, University Park 16802
Genetics 132:471-80. 1992..pseudoobscura. The nucleotide diversity data is consistent with direct and indirect measures of gene flow that show extensive dispersal between populations of D. pseudoobscura... - Nucleotide sequence analysis of Adh genes estimates the time of geographic isolation of the Bogota population of Drosophila pseudoobscuraS W Schaeffer
Department of Biology, Pennsylvania State University, University Park 16802
Proc Natl Acad Sci U S A 88:6097-101. 1991..This divergence time suggests that D. pseudoobscura extended its range from North America to South America in a period of Pleistocene glaciation, when habitat suitable for the species presumably existed in lowland Central America... - Polymorphism and divergence at a Drosophila pseudogene locusJ K Pritchard
Department of Biology, Pennsylvania State University, University Park 16802, USA
Genetics 147:199-208. 1997..Because the Lcp psi lies in a region of relatively infrequent recombination, we suggest that the low level of within-species polymorphism is the result of background selection... - Molecular population genetics of an electrophoretically monomorphic protein in the alcohol dehydrogenase region of Drosophila pseudoobscuraS W Schaeffer
Department of Biology, Pennsylvania State University, University Park 16802
Genetics 132:163-78. 1992..The neutral mutation parameter for synonymous sites is heterogeneous between domains of the Adh region. These data indicate that selective constrains on synonymous sites can vary between functional domains... - Molecular population genetics of sex determination genes: the transformer gene of Drosophila melanogasterC S Walthour
Department of Biology, Pennsylvania State University, University Park 16802
Genetics 136:1367-72. 1994..The lack of variability in the tra gene is consistent with a recent selective sweep of a beneficial allele in or near the tra locus... - Meiotic transmission of Drosophila pseudoobscura chromosomal arrangementsRichard P Meisel
Intercollege Graduate Program in Genetics, Institute of Molecular Evolutionary Genetics, and Department of Biology, Pennsylvania State University, University Park, Pennsylvania, United States of America
PLoS ONE 2:e530. 2007..pseudoobscura inversion system are most likely due to fitness differences of gene arrangement karyotypes in different environments... - Sulfide binding is mediated by zinc ions discovered in the crystal structure of a hydrothermal vent tubeworm hemoglobinJason F Flores
Department of Biology, Pennsylvania State University, University Park, PA 16802, USA
Proc Natl Acad Sci U S A 102:2713-8. 2005..pachyptila hemoglobins by addition of a thiol inhibitor were also unsuccessful. These findings challenge the currently accepted paradigm of annelid hemoglobin evolution and adaptation to reducing environments... - Adaptive evolution of genes duplicated from the Drosophila pseudoobscura neo-X chromosomeRichard P Meisel
Intercollege Graduate Program in Genetics, The Pennsylvania State University, PA, USA
Mol Biol Evol 27:1963-78. 2010.... - The ornithine decarboxylase gene of Trypanosoma brucei: Evidence for horizontal gene transfer from a vertebrate sourceCarolyn Steglich
Department of Biology, Slippery Rock University, Slippery Rock, PA 16057, USA
Infect Genet Evol 6:205-19. 2006..brucei, and Trypanosoma cruzi supports the hypothesis of loss of the Odc gene in the Trypanosoma lineage followed by acquisition of a new copy from a vertebrate host in the African branch of the genus... - Environmental differences in hemoglobin gene expression in the hydrothermal vent tubeworm, Ridgeia piscesaeSusan L Carney
Department of Biology, The Pennsylvania State University, University Park, PA 16802 5301, USA
Comp Biochem Physiol B Biochem Mol Biol 146:326-37. 2007..These data demonstrate that local environmental factors influence not only phenotype but gene expression and its resulting physiological outcome within this unique species... - Evolution of genes and genomes on the Drosophila phylogenyAndrew G Clark
Department of Molecular Biology and Genetics, Cornell University, Ithaca, New York 14853, USA
Nature 450:203-18. 2007..These may prove to underlie differences in the ecology and behaviour of these diverse species... - Divergence between the Drosophila pseudoobscura and D. persimilis genome sequences in relation to chromosomal inversionsMohamed A F Noor
Biology Department, Duke University, Durham, North Carolina 27708, USA
Genetics 177:1417-28. 2007..This reliance highlights the need for complementary genomic and population genetic approaches for tackling fundamental evolutionary questions such as speciation... - Chromosomal rearrangement inferred from comparisons of 12 Drosophila genomesArjun Bhutkar
Department of Molecular and Cellular Biology, Harvard University, Cambridge, Massachusetts 02138, USA
Genetics 179:1657-80. 2008..On the other hand, an analysis of the disruption of syntenic blocks between species allowed the identification of fixed inversion breakpoints and estimates of breakpoint reuse and lineage-specific breakpoint event segregation... - Comparative genome sequencing of Drosophila pseudoobscura: chromosomal, gene, and cis-element evolutionStephen Richards
Human Genome Sequencing Center and Department of Molecular and Human Genetics, Baylor College of Medicine, Houston Texas 77030, USA
Genome Res 15:1-18. 2005..Overall, a pattern of repeat-mediated chromosomal rearrangement, and high coadaptation of both male genes and cis-regulatory sequences emerges as important themes of genome divergence between these species of Drosophila...