scholarly journals Genetic variation for expression of the sex determination pathway genes in Drosophila melanogaster

2005 ◽  
Vol 86 (1) ◽  
pp. 31-40 ◽  
Author(s):  
AARON M. TARONE ◽  
YASEEN M. NASSER ◽  
SERGEY V. NUZHDIN
Keyword(s):  
Drosophila Melanogaster ◽  
Genetic Variation ◽  
Sex Determination ◽  
Transcript Level ◽  
Morphological Characters ◽  
Adult Males ◽  
Transcript Levels ◽  
Downstream Target ◽  
Trade Offs ◽  
Males And Females

Sequence polymorphisms result in phenotypic variation through the pathways of interacting genes and their products. We focused on transcript-level variation in the splicing pathway for sex determination – a model network defining downstream morphological characters that are dimorphic between males and females. Expression of Sex lethal, transformer, transformer2, doublesex, intersex and hermaphrodite was assayed with quantitative RT-PCR in 0- to 1-day-old adult males and females of 36 Drosophila melanogaster inbred lines. Abundant genetic variation in the transcript levels was found for all genes. Sex-specific splices had high concentrations in the appropriate sex. In the other sex, low but detectable concentrations were also observed. Abundances of splices strongly co-varied between sexes among genotypes, with little genetic variation strictly limited to one sex. The level of sexually dimorphic Yolk protein1 expression – an immediate downstream target of the pathway – was modelled as the target phenotype of the upstream sex determination pathway. Substantial genetic variation in this phenotype in males was explained by leaky splicing of female-specific transcripts. If higher transcript levels of the appropriate isoform of sex determination genes are beneficial in a sex, then stronger leakiness of the inappropriate transcript might be deleterious, perhaps contributing to the fitness trade-offs previously observed between the sexes.

scholarly journals Multiple Toll-Spätzle Pathways in Drosophila melanogaster Immunity

2018 ◽  
Author(s):  
Munmun Chowdhury ◽  
Chun-Feng Li ◽  
Zhen He ◽  
Yuzhen Lu ◽  
Xusheng Liu ◽  
...  
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Drosophila Melanogaster ◽  
Candida Albicans ◽  
Systemic Infection ◽  
Defense Responses ◽  
Immune Defense ◽  
Adult Males ◽  
Male And Female ◽  
Vesicular Stomatitis ◽  
Males And Females

AbstractThe Drosophila melanogaster Toll-Spätzle pathway plays an important role in development and immunity. Drosophila genome encodes nine Toll receptors and six Spätzle (Spz) proteins, and only the canonical Toll-Spz (Toll-1-Spz-1) pathway has been well investigated. In this study, we compared the nine Drosophila Tolls and showed that similarly to Toll, Toll-7 also strongly activated drosomycin promoter. Importantly, we showed that both Toll and Toll-7 interacted with Spz, Spz-2 and Spz-5, and co-expression of Toll or Toll-7 with Spz, Spz-2 and Spz-5 activated the drosomycin promoter. Furthermore, Toll and Toll-7 both recognized vesicular stomatitis virus (VSV) by binding to the VSV glycoprotein. Septic infection in Toll and Toll-7 mutant flies suggested that Toll and Toll-7 differentially affected defense responses in adult males and females after systemic infection by Enterococcus faecalis, Pseudomonas aeruginosa, Candida albicans or VSV. Our results suggest multiple Toll family members activate the expression of antimicrobial peptides. Our results also provide evidence that Toll and Toll-7 bind multiple Spätzle proteins and differentially affect immune defense against different pathogens in adult male and female flies.

scholarly journals A non-coding indel polymorphism in the fruitless gene of Drosophila melanogaster exhibits antagonistically pleiotropic fitness effects

2021 ◽  
Vol 288 (1950) ◽  
Author(s):  
Michael D. Jardine ◽  
Filip Ruzicka ◽  
Charlotte Diffley ◽  
Kevin Fowler ◽  
Max Reuter
Keyword(s):  
Drosophila Melanogaster ◽  
Genetic Variation ◽  
Balancing Selection ◽  
Antagonistic Pleiotropy ◽  
Multiple Target ◽  
Indel Polymorphism ◽  
Fitness Components ◽  
Fitness Effects ◽  
Males And Females ◽  
Opposing Effects

The amount of genetic variation for fitness within populations tends to exceed that expected under mutation–selection–drift balance. Several mechanisms have been proposed to actively maintain polymorphism and account for this discrepancy, including antagonistic pleiotropy (AP), where allelic variants have opposing effects on different components of fitness. Here, we identify a non-coding indel polymorphism in the fruitless gene of Drosophila melanogaster and measure survival and reproductive components of fitness in males and females of replicate lines carrying each respective allele. Expressing the fruitless region in a hemizygous state reveals a pattern of AP, with one allele generating greater reproductive fitness and the other conferring greater survival to adulthood. Different fitness effects were observed in an alternative genetic background, which may reflect dominance reversal and/or epistasis. Our findings link sequence-level variation at a single locus with complex effects on a range of fitness components, thus helping to explain the maintenance of genetic variation for fitness. Transcription factors, such as fruitless , may be prime candidates for targets of balancing selection since they interact with multiple target loci and their associated phenotypic effects.

scholarly journals Genetic variation in male-induced harm in Drosophila melanogaster

2016 ◽  
Vol 12 (4) ◽  
pp. 20160105 ◽  
Author(s):  
David C. S. Filice ◽  
Tristan A. F. Long
Keyword(s):  
Drosophila Melanogaster ◽  
Genetic Variation ◽  
Prolonged Exposure ◽  
Harmful Effect ◽  
Accessory Gland ◽  
Evolutionary Significance ◽  
Male Body ◽  
Accessory Gland Proteins ◽  
Trade Offs ◽  
Fitness Index

In Drosophila melanogaster , prolonged exposure to males reduces the longevity and fecundity of females. This harm arises from the effects of male courtship behaviours and the toxic side effects of the accessory gland proteins (Acps) in their seminal fluids. Here, we examine the relationship between male exposure and its harmful effect on the lifetime fitness of his mates, and quantify the genetic basis for this variation. We found significant additive genetic variation in the magnitude of harm that males impose on females by exposing females to males from a variety of hemiclonal backgrounds for either a brief or prolonged period of time and measuring their fecundity, a meaningful fitness index. Furthermore, we discovered a strong negative correlation between the magnitude of harm and the short-term effects of male exposure on female fitness. We discuss the evolutionary significance of these results with regards to potential life-history trade-offs in females, and its relationship to male body size.

scholarly journals A non-coding indel polymorphism in the fruitless gene of Drosophila melanogaster exhibits antagonistically pleiotropic fitness effects

2020 ◽  
Author(s):  
Michael D. Jardine ◽  
Filip Ruzicka ◽  
Charlotte Diffley ◽  
Kevin Fowler ◽  
Max Reuter
Keyword(s):  
Drosophila Melanogaster ◽  
Genetic Variation ◽  
Balancing Selection ◽  
The Other ◽  
Antagonistic Pleiotropy ◽  
Indel Polymorphism ◽  
Fitness Components ◽  
Fitness Effects ◽  
Males And Females ◽  
Opposing Effects

AbstractThe amount of genetic variation for fitness within populations tends to exceed that expected under mutation-selection-drift balance. Several mechanisms have been proposed to actively maintain polymorphism and account for this discrepancy, including antagonistic pleiotropy (AP), where allelic variants have opposing effects on different components of fitness. Here we identify a non-coding indel polymorphism in the fruitless gene of Drosophila melanogaster and measure survival and reproductive components of fitness in males and females of replicate lines carrying one or the other allele. Expressing the fruitless region in a hemizygous state we observe a pattern of AP, with one allele resulting in greater reproductive fitness while the other confers greater survival to adulthood. Different fitness effects were observed in an alternative genetic background, suggesting widespread epistatic effects. Our findings link sequence-level variation at a single locus with complex effects on a range of fitness components, thus helping to explain the maintenance of genetic variation for fitness. Transcription factors, such as fruitless, may be prime candidates for targets of balancing selection since they interact with multiple target loci and their associated phenotypic effects.

GENETIC VARIABILITY FOR DENSITY SENSITIVITY OF THREE COMPONENTS OF FITNESS IN DROSOPHILA MELANOGASTER

Genetics ◽  
1982 ◽  
Vol 101 (2) ◽  
pp. 301-316
Author(s):  
R William Marks
Keyword(s):  
Drosophila Melanogaster ◽  
Genetic Variation ◽  
Life Cycle ◽  
Density Dependence ◽  
Exact Nature ◽  
Mathematical Form ◽  
Fitness Components ◽  
Natural Genetic Variation ◽  
Trade Offs ◽  
Three Components

ABSTRACT This study examines natural genetic variation in density sensitivity of three components of fitness in Drosophila melanogaster using the method of chromosome extraction. Different lines are differentially sensitive to density. The distribution of measures of density sensitivity of chromosomal homozygotes is different from that of random chromosomal heterozygotes for both location and dispersion. Density sensitivity of the components is about as variable as any of the fitness components themselves at fixed densities. The consequences of the exact nature of this density dependence are discussed with respect to the stage of the life cycle at which density dependence occurs, and the mathematical form that it takes. There is no evidence of trade-offs among the components or their density sensitivity.

Ecdysteroids in adult males and females of Drosophila melanogaster

1984 ◽  
Vol 30 (10) ◽  
pp. 823-830 ◽  
Author(s):  
Mary Bownes ◽  
Andreas Dübendorfer ◽  
Trevor Smith
Keyword(s):  
Drosophila Melanogaster ◽  
Adult Males ◽  
Males And Females

scholarly journals BumbleKey: an interactive key for the identification of bumblebees of Italy and Corsica (Hymenoptera, Apidae)

ZooKeys ◽  
2018 ◽  
Vol 784 ◽  
pp. 127-138
Author(s):  
Andree Cappellari ◽  
Maurizio Mei ◽  
Massimo Lopresti ◽  
Pierfilippo Cerretti
Keyword(s):  
Open Access ◽  
Morphological Characters ◽  
Adult Males ◽  
Males And Females

BumbleKey is a matrix-based, interactive key to all 45 species of bumblebees of Italy and Corsica. The key allows to identify adult males and females (queens and workers) using morphological characters. The key is published online, open-access, at http://www.interactive-keys.eu/bumblekey/default.aspx.

The taxonomic status of the Japanese citrus flower-bud midge, Contarinia okadai (Miyoshi) comb. n., and of the citrus blossom midge, C. citri Barnes (Diptera: Cecidomyiidae)

1980 ◽  
Vol 70 (2) ◽  
pp. 277-285 ◽  
Author(s):  
K. M. Harris ◽  
J. Yukawa
Keyword(s):  
Host Plants ◽  
Gall Midge ◽  
Taxonomic Status ◽  
Morphological Characters ◽  
Adult Males ◽  
Flower Bud ◽  
The Status ◽  
Taxonomic Research ◽  
Western Japan ◽  
Males And Females

AbstractA gall midge that attacks citrus flower buds in south-western Japan is redescribed under the name Contarinia okadai (Miyoshi) comb. n. and is compared with C. citri Barnes, which was originally described from cultivated citrus in Mauritius. C. okadai, for which a neotype is designated, is distinguished from C. citri by morphological characters of the adult males and females and of the larvae. The known host-plants, biology and distribution of C. okadai are recorded, and new Japanese and English names for the species are proposed. The status of records of C. citri from Sicily, Cyprus, Israel, India, China and Hong Kong is discussed, and the need for further taxonomic research is stressed.

Systematic revision of the Andean butterfly genus Orophila Staudinger, 1886 (Lepidoptera: Nymphalidae: Biblidinae)

Zootaxa ◽  
2017 ◽  
Vol 4258 (5) ◽  
pp. 443
Author(s):  
ANNA ZUBEK ◽  
TOMASZ PYRCZ ◽  
JADWIGA LORENC-BRUDECKA ◽  
PIERRE BOYER ◽  
JOSE CERDEÑA ◽  
...  
Keyword(s):  
Systematic Review ◽  
Geographical Distribution ◽  
Male Genitalia ◽  
Morphological Characters ◽  
Adult Males ◽  
Systematic Revision ◽  
Males And Females ◽  
First Time

A systematic review of the Neotropical butterfly genus Orophila Staudinger, 1886 based on morphological characters and geographical distribution is presented. Four species are recognized: O. campaspe (Hewitson, 1869) stat. rest., O. cardases (Hewitson, 1869), O. cecidas (Hewitson, 1869) stat. rest. and O. diotima (Hewitson, 1852). Other changes proposed include treating Orophila diotima footei (Lamas, 2003) syn. n. and O. cardases zurita (Fruhstorfer, 1916) syn. n. as synonyms of other taxa. Illustrations of adult males and male genitalia of all taxa are presented and the importance of morphological characters in both males and females is evaluated. Female specimens and genitalia are illustrated for the first time for O. c. cardases, O. cecidas and O. diotima. Lectotypes are designated for two nominal taxa.

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