Louis Bernard Klaczko

Publications

• 3.25

  Impact points

  Spiroplasma in Drosophila melanogaster Populations: Prevalence, Male-Killing, Molecular Identification, and No Association with Wolbachia.

  Iuri M Ventura, Ayana B Martins, Mariana L Lyra, Carlos A C Andrade, Klélia A Carvalho, Louis B Klaczko

  Microbial ecology. 05/2012;

  Spiroplasma endosymbionts are maternally transmitted bacteria that may kill infected sons resulting in the production of female-biased broods. The prevalence of male killers varies considerably both between and within species. Here, we evaluate the spatial and temporal status of male-killing and non... [more] Spiroplasma endosymbionts are maternally transmitted bacteria that may kill infected sons resulting in the production of female-biased broods. The prevalence of male killers varies considerably both between and within species. Here, we evaluate the spatial and temporal status of male-killing and non-male-killing Spiroplasma infection in three Brazilian populations of Drosophila melanogaster, nearly a decade after the first occurrence report for this species. The incidence of the male-killing Spiroplasma ranged from close to 0 to 17.7 % (so far the highest estimate for a Drosophila species) with a suggestion of temporal decline in a population. We also found non-male-killing Spiroplasma coexisting in one population at lower prevalence (3-5 %), and we did not detect it in the other two. This may be taken as a suggestion of a spreading advantage conferred by the male-killing strategy. Sequencing two loci, we identified the phylogenetic position of Spiroplasma strains from the three localities, showing that all strains group closely in the poulsonii clade. Due to intensive sampling effort, we were able to test the association between Spiroplasma infections and another widespread endosymbiont, Wolbachia, whose prevalence ranged from 81.8 to 100 %. The prevalence of Wolbachia did not differ between Spiroplasma-infected and uninfected strains in our largest sample nor were the prevalences of the two endosymbionts associated across localities.
• 3.56

  Impact points

  Molecular phylogeny of the Drosophila tripunctata and closely related species groups (Diptera: Drosophilidae).

  Luciane Mendes Hatadani, James O McInerney, Hermes Fonseca de Medeiros, Ana Carolina Martins Junqueira, Ana Maria de Azeredo-Espin, Louis Bernard Klaczko

  Molecular phylogenetics and evolution. 04/2009;

  We suggest a new phylogenetic hypothesis for the tripunctata radiation based on sequences of mitochondrial genes. Phylogenetic trees were reconstructed by parsimony, maximum likelihood and Bayesian methods. We performed tests for hypotheses of monophyly for taxonomic groups and other specific hypoth... [more] We suggest a new phylogenetic hypothesis for the tripunctata radiation based on sequences of mitochondrial genes. Phylogenetic trees were reconstructed by parsimony, maximum likelihood and Bayesian methods. We performed tests for hypotheses of monophyly for taxonomic groups and other specific hypotheses. Results reject the monophyly for the tripunctata group whereas monophyly is not rejected for the tripunctata radiation and other specific groups within the radiation. Although most of the basal nodes were unresolved we were able to identify four clusters within the tripunctata radiation. These results suggest the collection of additional data before a proper taxonomic revision could be proposed.
• 5.43

  Impact points

  THE REACTION NORM FOR ABDOMINAL PIGMENTATION AND ITS CURVE IN DROSOPHILA MEDIOPUNCTATA DEPEND ON THE MEAN PHENOTYPIC VALUE.

  Felipe Rocha, Hermes F Medeiros, Louis Bernard Klaczko

  Evolution; international journal of organic evolution. 09/2008;

  The idea of a general independence between the phenotypic plasticity and the mean value of a trait is, presently, a consensus. Here, we use the reaction norm of abdominal pigmentation (number of dark spots) of Drosophila mediopunctata in response to temperature, to test this idea. We raised eight st... [more] The idea of a general independence between the phenotypic plasticity and the mean value of a trait is, presently, a consensus. Here, we use the reaction norm of abdominal pigmentation (number of dark spots) of Drosophila mediopunctata in response to temperature, to test this idea. We raised eight strains, bearing two different chromosomal inversions and with varying mean phenotypic values, under 11 temperatures in a thermal gradient to test for predictions concerning mean phenotypic values, chromosomal inversions and reaction norms. Our results revealed a strong effect of different phenotypic groups and no effect of different karyotypes on reaction norms. Moreover, we found a significant negative correlation between mean phenotypic value and the curvature of the reaction norms, revealing a high dependency of the reaction norm shape on mean phenotypic value. These results clearly reject the idea of genetic independence between mean value and phenotypic plasticity, and may indicate a pattern of correlation, which may include results from other traits and species, with an importance that has not been fully appreciated.
• 2.09

  Impact points

  Shape and size variation on the wing of Drosophila mediopunctata: influence of chromosome inversions and genotype-environment interaction.

  Luciane Mendes Hatadani, Louis Bernard Klaczko

  Genetica. 08/2008; 133(3):335-42.

  The second chromosome of Drosophila mediopunctata is highly polymorphic for inversions. Previous work reported a significant interaction between these inversions and collecting date on wing size, suggesting the presence of genotype-environment interaction. We performed experiments in the laboratory ... [more] The second chromosome of Drosophila mediopunctata is highly polymorphic for inversions. Previous work reported a significant interaction between these inversions and collecting date on wing size, suggesting the presence of genotype-environment interaction. We performed experiments in the laboratory to test for the joint effects of temperature and chromosome inversions on size and shape of the wing in D. mediopunctata. Size was measured as the centroid size, and shape was analyzed using the generalized least squares Procrustes superimposition followed by discriminant analysis and canonical variates analysis of partial warps and uniform components scores. Our findings show that wing size and shape are influenced by temperature, sex, and karyotype. We also found evidence suggestive of an interaction between the effects of karyotype and temperature on wing shape, indicating the existence of genotype-environment interaction for this trait in D. mediopunctata. In addition, the association between wing size and chromosome inversions is in agreement with previous results indicating that these inversions might be accumulating alleles adapted to different temperatures. However, no significant interaction between temperature and karyotype for size was found--in spite of the significant presence of temperature-genotype (cross) interaction. We suggest that other ecological factors--such as larval crowding--or seasonal variation of genetic content within inversions may explain the previous results.
• 3.56

  Impact points

  Grafting the molecular phylogenetic tree with morphological branches to reconstruct the evolutionary history of the genus Zaprionus (Diptera: Drosophilidae).

  Amir Yassin, Luciana O Araripe, Pierre Capy, Jean-Luc Da Lage, Louis Bernard Klaczko, Claude Maisonhaute, David Ogereau, Jean R David

  Molecular phylogenetics and evolution. 07/2008; 47(3):903-15.

  A molecular phylogeny for the drosophilid genus Zaprionus was inferred using a mitochondrial (CO-II) and a nuclear (Amyrel) gene using 22 available species. The combined molecular tree does not support the current classification, dubbed phylogenetic, based entirely upon a morphocline of forefemoral ... [more] A molecular phylogeny for the drosophilid genus Zaprionus was inferred using a mitochondrial (CO-II) and a nuclear (Amyrel) gene using 22 available species. The combined molecular tree does not support the current classification, dubbed phylogenetic, based entirely upon a morphocline of forefemoral ornamentation. For species for which DNA was not available, phylogenetic positioning was only assigned using morphological characters. In order to avoid conflict between DNA and morphology in the combined analyses (supermatrix method), we developed a new method in which few morphological characters were sampled according to an a priori homoplasy assessment on the consensus molecular tree. At each internal node of the tree, a number of synapomorphies was determined, and species with no molecular sequences were grafted thereon. Analogously to tree vocabulary, we called our method 'morphological grafting'. New species groups and complexes were then defined in the light of our findings. Further, divergence times were estimated under a relaxed molecular clock, and historical biogeography was reconstructed under a maximum likelihood model. Zaprionus appears to be of recent origin in the Oriental region during the Late Miocene ( approximately 10 MYA), and colonization of Africa started shortly after ( approximately 7 MYA) via the maritime route of the Indian Ocean Islands. Most of the morphological and ecological diversification took place, later, in Western Africa during the Quaternary cyclic climatic changes. Furthermore, some species became recent invaders, with one, Zaprionus indianus, has successfully invaded South and North America during the last decade.
• 2.09

  Impact points

  Inversion polymorphism and a new polytene chromosome map of Zaprionus indianus Gupta (1970) (Diptera: Drosophilidae).

  Galina Ananina, Cláudia Rohde, Jean R David, Vera L S Valente, Louis B Klaczko

  Genetica. 11/2007; 131(2):117-25.

  Zaprionus indianus is a recent invader in Brazil and was probably introduced from the West Afrotropical zone. So far, studies regarding its chromosomal polymorphism were limited to India. We found that Brazilian populations were very different from Indian ones. Five new inversions have been discover... [more] Zaprionus indianus is a recent invader in Brazil and was probably introduced from the West Afrotropical zone. So far, studies regarding its chromosomal polymorphism were limited to India. We found that Brazilian populations were very different from Indian ones. Five new inversions have been discovered. In(II)A, already described in India, where it is quite common, has also been found in Brazil, where it is very rare. The X-chromosome has three inversions; In(X)Na, In(X)Ke and In(X)Eg, which are frequent in all Brazilian populations studied. In every case, we observed strong linkage disequilibrium among these gene arrangements. During the primary collection period (2001-2002), we noticed a significant positive correlation between the frequency of these inversions and latitude, but this was not confirmed in later investigations. Rearrangement In(IV)EF was also common in all populations, while inversion In(V)B was only found in southern populations. Our data suggest that the founders that recently invaded Brazil were polymorphic for the six inversions observed. The place of origin might be identified more precisely by investigating West African populations. In order to facilitate further investigations, we present an updated polytene chromosome photomap, locating the breakpoints of every inversion observed in Brazilian populations.
• 2.09

  Impact points

  Evolutionary genetics of Drosophila mediopunctata.

  Louis Bernard Klaczko

  Genetica. 02/2006; 126(1-2):43-55.

  Drosophila mediopunctata belongs to the tripunctata group, which is the second largest Neotropical group of Drosophila with 64 species described. Here I review the work done with this forest dwelling species, and some applications of the methods developed using it as a model organism, to other speci... [more] Drosophila mediopunctata belongs to the tripunctata group, which is the second largest Neotropical group of Drosophila with 64 species described. Here I review the work done with this forest dwelling species, and some applications of the methods developed using it as a model organism, to other species. Specifically I look at: the phylogenetic status of the tripunctata group and its relation with other groups in the Hirtodrosophila-immigrans radiation; D. mediopunctata's chromosome inversion polymorphism (altitudinal cline of frequencies and evidences of selection); the morphological variation of the wing and the development and applications of the ellipse method to describe the morphology of the wing; the variation on the number of aristal branches; the genetic basis of the polychromatism present in D. mediopunctata and its association with chromosome inversions; the sex-ratio trait and its use in the demonstration of Fisher's principle; and, finally, the finding of the transposable P-element in this species.
• 1.92

  Impact points

  Analysis of mitochondrial DNA variability and genetic structure in populations of New World screwworm flies (Diptera: Calliphoridae) from Uruguay.

  Mariana Lúcio Lyra, Pablo Fresia, Santos Gama, Juan Cristina, Louis Bernard Klaczko, Ana Maria Lima de Azeredo-Espin

  Journal of medical entomology. 08/2005; 42(4):589-95.

  The New Word screwworm, Cochliomyia hominivorax (Coquerel 1858) (Diptera: Calliphoridae), is one of the most important insect pests of livestock in the Neotropical region. In this work, polymerase chain reaction-restriction fragment length polymorphism of mitochondrial DNA (mtDNA) was used to study ... [more] The New Word screwworm, Cochliomyia hominivorax (Coquerel 1858) (Diptera: Calliphoridae), is one of the most important insect pests of livestock in the Neotropical region. In this work, polymerase chain reaction-restriction fragment length polymorphism of mitochondrial DNA (mtDNA) was used to study the diversity and population structure of seven geographically distinct populations of C. hominivorax from most of the important livestock areas in Uruguay. The control region (A+T/12S) and subunits 1 and 2 of cytochrome oxidase (cox1/cox2) were amplified and digested with restriction endonucleases. Nine haplotypes were observed among the populations sampled. The mean nucleotide diversity and the haplotype diversity indicated high mtDNA variability in this species. The similarity index, average nucleotide divergence, and analysis of molecular variance results showed no evidence of subpopulation differentiation, indicating that the C. hominivorax populations of Uruguay form a single panmitic population. The distribution pattern of the genetic variation in natural populations of C. hominivorax and the implications of these results for establishing control program are discussed.

• Chromosomal inversion polymorphism in Drosophila mediopunctata: seasonal, altitudinal, and latitudinal variation

  Galina Ananina, Peixoto Alexandre A, Bitner-Mathé Blanche C, Souza Wilma N, Silva Luciano Basso da, Valente Vera L.S, Klaczko Louis B

  Genetics and Molecular Biology. 01/2004;

  The most polymorphic chromosome for inversions in Drosophila mediopunctata is the chromosome II, where 17 inversions have been found, eight of which occurring in the distal region and nine in the proximal region. We present an analysis of the chromosome II inversion polymorphism with respect to seas... [more] The most polymorphic chromosome for inversions in Drosophila mediopunctata is the chromosome II, where 17 inversions have been found, eight of which occurring in the distal region and nine in the proximal region. We present an analysis of the chromosome II inversion polymorphism with respect to seasonal, altitudinal and latitudinal variation. In D. mediopunctata from the Parque Nacional do Itatiaia (southeastern Brazil), the frequencies of three of the distal inversions (namely DA, DS, and DP) vary seasonally. These inversions also show altitudinal clines in their frequencies. This microgeographic pattern was not observed on a macrogeographic scale. D. mediopunctata from Porto Alegre are less polymorphic for inversions than other populations, the most remarkable reduction occurring in the proximal region of chromosome II. There is a considerable difference between D. mediopunctata from Campinas and specimens from Serra do Japi, which are separated by only 50 km. In contrast, D. mediopunctata from Serra do Japi are much more similar to specimens from the Parque Nacional do Itatiaia, which is 200 km far.
• 3.56

  Impact points

  A molecular study of the systematics of the Drosophila tripunctata group and the tripunctata radiation.

  Karla S C Yotoko, Hermes F Medeiros, Vera N Solferini, Louis B Klaczko

  Molecular phylogenetics and evolution. 10/2003; 28(3):614-9.
• 2.10

  Impact points

  Polytene chromosome map and inversion polymorphism in Drosophila mediopunctata.

  Galina Ananina, Alexandre A Peixoto, Wilma N Souza, Louis B Klaczko

  Memórias do Instituto Oswaldo Cruz. 08/2002; 97(5):691-4.

  Drosophila mediopunctata belongs to the tripunctata group, and is one of the commonest Drosophila species collected in some places in Brazil, especially in the winter. A standard map of the polytene chromosomes is presented. The breakpoints of the naturally occurring chromosomal rearrangements are m... [more] Drosophila mediopunctata belongs to the tripunctata group, and is one of the commonest Drosophila species collected in some places in Brazil, especially in the winter. A standard map of the polytene chromosomes is presented. The breakpoints of the naturally occurring chromosomal rearrangements are marked on the map. The distribution of breaking points through the chromosomes of D. mediopunctata is apparently non-random. Chromosomes X, II and IV show inversion polymorphisms. Chromosome II is the most polymorphic, with 17 inversions, 8 inversions in the distal region and 9 in the proximal region. Chromosome X has four different gene arrangements, while chromosome IV has only two.

• Concanavalin A-reactive nuclear matrix glycoprotein

  Vidal Benedicto de Campos, Maria Silvya Stuchi, Klaczko Louis Bernard

  Brazilian Journal of Genetics. 01/1997;

  The binding capacity of concanavalin A (Con A) to condensed euchromatin and heterochromatin was investigated in chicken erythrocyte nuclei (CEN), mouse liver cells, Zea mays mays meristematic cells and Drosophila melanogaster polytene chromosomes after 4 N HCl hydrolysis to determine whether binding... [more] The binding capacity of concanavalin A (Con A) to condensed euchromatin and heterochromatin was investigated in chicken erythrocyte nuclei (CEN), mouse liver cells, Zea mays mays meristematic cells and Drosophila melanogaster polytene chromosomes after 4 N HCl hydrolysis to determine whether binding was preferentially occurring in bands and heterochromatin. Dry mass (DM) variation was investigated in CEN by interference microscopy. Feulgen and Con A reactions were employed for all materials to correlate the loci of the two reactions. Quantifications and topological verifications were carried out by video image analysis (high performance cytometry). It was observed that 4 N HCl hydrolysis caused an important DM loss in CEN leaving a level corresponding to the average DNA DM content. In this material, Con A binding was restricted to the nuclear envelope, which reinforces the idea of the absence of a nuclear matrix in these cells. The other cell types exhibited a correspondence of Feulgen-positive and Con A-reactive areas. The Con A reaction was highly positive in the condensed chromatin areas and heterochromatin. This fact led us to speculate that Con A-positive proteins may play a role in the chromatin condensation mechanism, endowing this structure with physico-chemical stability towards acid hydrolysis and contributing to its rheological properties.
• 3.89

  Impact points

  Genetic Variation for Dispersal by DROSOPHILA PSEUDOOBSCURA and DROSOPHILA PERSIMILIS.

  Louis Bernard Klaczko, Charles E Taylor, Jeffrey R Powell

  Genetics. 03/1986; 112(2):229-235.

  Release-recapture experiments using Drosophila pseudoobscura and D. persimilis strains of different karyotypes were performed in a heterogeneous environment. The heterogeneity was due to both spatial variation and the species of yeast used to attract the released flies. No karyotypic-specific habita... [more] Release-recapture experiments using Drosophila pseudoobscura and D. persimilis strains of different karyotypes were performed in a heterogeneous environment. The heterogeneity was due to both spatial variation and the species of yeast used to attract the released flies. No karyotypic-specific habitat preferences were detected. However, in all releases, different strains did behave differently with respect to one or both of the heterogeneous factors. These results indicate there is variation for dispersal behavior in these species that is most likely based on genotype-dependent habitat preferences.

• Phenotypic plasticity of the aedeagus of Drosophila mediopunctata: Effect of the temperature

  Carlos A.C. Andrade, Luciane M. Hatadani, Louis B. Klaczko

  Journal of Thermal Biology.

  In this study, we analyzed the phenotypic plasticity of the male intromittent organ (aedeagus) of Drosophila mediopunctata genitalia in response to temperature. Size and shape of the aedeagus were examined with univariate statistics and geometric morphometrics. The following results emerged: firstly... [more] In this study, we analyzed the phenotypic plasticity of the male intromittent organ (aedeagus) of Drosophila mediopunctata genitalia in response to temperature. Size and shape of the aedeagus were examined with univariate statistics and geometric morphometrics. The following results emerged: firstly, flies raised at 16.5 °C had bigger aedeagi than those raised at 20 °C; secondly, significant differences in shape were also found between the two groups of flies, mainly in the apical area, located using the thin-plate spline interpolating function; thirdly, the coefficients of variation for the traits of the aedeagus were comparable to other traits in Drosophila and likewise to genital traits in other organisms. These findings were analyzed in an evolutionary context.

• Autosomal suppressors of sex-ratio in Drosophila mediopunctata

  Antonio Bernardo de Carvalho, Louis Bernard Klaczko

• Grafting the molecular phylogenetic tree with morphological branches to reconstruct the evolutionary history of the genus Zaprionus (Diptera: Drosophilidae)

  Amir Yassin, Luciana O. Araripe, Pierre Capy, Jean-Luc Da Lage, Louis Bernard Klaczko, Claude Maisonhaute, David Ogereau, Jean R. David

  Molecular Phylogenetics and Evolution.

  A molecular phylogeny for the drosophilid genus Zaprionus was inferred using a mitochondrial (CO-II) and a nuclear (Amyrel) gene using 22 available species. The combined molecular tree does not support the current classification, dubbed phylogenetic, based entirely upon a morphocline of forefemoral ... [more] A molecular phylogeny for the drosophilid genus Zaprionus was inferred using a mitochondrial (CO-II) and a nuclear (Amyrel) gene using 22 available species. The combined molecular tree does not support the current classification, dubbed phylogenetic, based entirely upon a morphocline of forefemoral ornamentation. For species for which DNA was not available, phylogenetic positioning was only assigned using morphological characters. In order to avoid conflict between DNA and morphology in the combined analyses (supermatrix method), we developed a new method in which few morphological characters were sampled according to an a priori homoplasy assessment on the consensus molecular tree. At each internal node of the tree, a number of synapomorphies was determined, and species with no molecular sequences were grafted thereon. Analogously to tree vocabulary, we called our method ‘morphological grafting’. New species groups and complexes were then defined in the light of our findings. Further, divergence times were estimated under a relaxed molecular clock, and historical biogeography was reconstructed under a maximum likelihood model. Zaprionus appears to be of recent origin in the Oriental region during the Late Miocene (∼10 MYA), and colonization of Africa started shortly after (∼7 MYA) via the maritime route of the Indian Ocean Islands. Most of the morphological and ecological diversification took place, later, in Western Africa during the Quaternary cyclic climatic changes. Furthermore, some species became recent invaders, with one, Zaprionus indianus, has successfully invaded South and North America during the last decade.

• Molecular phylogeny of the Drosophila tripunctata and closely related species groups (Diptera: Drosophilidae)

  Luciane Mendes Hatadani, James O. McInerney, Hermes Fonseca de Medeiros, Ana Carolina Martins Junqueira, Ana Maria de Azeredo-Espin, Louis Bernard Klaczko

  Molecular Phylogenetics and Evolution.

  We suggest a new phylogenetic hypothesis for the tripunctata radiation based on sequences of mitochondrial genes. Phylogenetic trees were reconstructed by parsimony, maximum likelihood and Bayesian methods. We performed tests for hypotheses of monophyly for taxonomic groups and other specific hypoth... [more] We suggest a new phylogenetic hypothesis for the tripunctata radiation based on sequences of mitochondrial genes. Phylogenetic trees were reconstructed by parsimony, maximum likelihood and Bayesian methods. We performed tests for hypotheses of monophyly for taxonomic groups and other specific hypotheses. Results reject the monophyly for the tripunctata group whereas monophyly is not rejected for the tripunctata radiation and other specific groups within the radiation. Although most of the basal nodes were unresolved we were able to identify four clusters within the tripunctata radiation. These results suggest the collection of additional data before a proper taxonomic revision could be proposed.
• 2.09

  Impact points

  Sexual dimorphism of body size and sternopleural bristle number: a comparison of geographic populations of an invasive cosmopolitan drosophilid.

  Jean R David, Luciana O Araripe, Blanche C Bitner-Mathé, Pierre Capy, Beatriz Goñi, Louis Bernard Klaczko, Hélène Legout, Marlucia B Martins, Joseph Vouidibio, Amir Yassin, Brigitte Moreteau

  Genetica. 128(1-3):109-22.

  Zaprionus indianus is a cosmopolitan drosophilid, of Afrotropical origin, which has recently colonized South America. The sexual dimorphism (SD) of body size is low, males being almost as big as females. We investigated 10 natural populations, 5 from America and 5 from Africa, using the isofemale li... [more] Zaprionus indianus is a cosmopolitan drosophilid, of Afrotropical origin, which has recently colonized South America. The sexual dimorphism (SD) of body size is low, males being almost as big as females. We investigated 10 natural populations, 5 from America and 5 from Africa, using the isofemale line technique. Three traits were measured on each fly: wing and thorax length and sternopleural bristle number. Two indices of SD were compared, and found to be highly correlated (r > 0.99). For the sake of simplicity, only the female/male (F/M) ratio was further considered. A significant genetic variability of SD was found in all cases, although with a low heritability (intra-class correlation of 0.13), about half the value found for the traits themselves. For size SD, we did not find any variation among continents or any latitudinal trend, and average values were 1.02 for wing length and 1.01 for thorax length. Bristle number SD was much greater (1.07). Among mass laboratory strains, SD was genetically much more variable than in recently collected populations, a likely consequence of laboratory drift. Altogether, SD, although genetically variable and prone to laboratory drift, is independent of size variations and presumably submitted to a stabilizing selection in nature.

• Morphological variation in a natural population of Drosophila mediopunctata: altitudinal cline, temporal changes and influence of chromosome inversions

  Blanche C Bitner-MathÉ, Alexandre A Peixoto, Louis B Klaczko