INVITATION PAPER: BEHAVIOR IN DROSOPHILA MELANOGASTER A GENETICIST'S VIEW

1974 ◽  
Vol 16 (4) ◽  
pp. 713-735 ◽  
Author(s):  
David T. Suzuki
Keyword(s):  
Drosophila Melanogaster ◽  
Sodium Channel ◽  
Temperature Sensitivity ◽  
Temperature Sensitive ◽  
Neuronal System ◽  
Neurological Development ◽  
Temperature Changes ◽  
Early Embryos ◽  
Induced Changes

In screening Drosophila melanogaster for mutations which cause paralysis at 29cC and recovery of mobility at 22cC, 11 temperature-sensitive (ts) mutants were detected among 1.35 × 106 flies screened. These mutations fell into 3 loci, paralytic (parats), shibire (shits) and stoned (stnts). All three loci affect neurological development. The best explanation for parats appears to be an effect on the inhibitory neuronal system. The shi alleles affect an array of developmental events from early embryos to adults. The pattern of heat-induced changes in shits1 electroretinograms (ERG) is consistent with a ts membranal defect. This is supported by a ts resistance of shits flies to tetrodotoxin which specifically blocks the sodium channel of nerves.The final locus, stn, causes sensitivity to the trauma of temperature changes. A jump response observed when a light is turned off is related to a large "offtransient" in ERGs which is correlated with a simultaneous muscle spike. The property of temperature-sensitivity allows greater analytic powers in the study of neurological mutants.

Temperature Sensitivity of Intracellular and Extracellular Soil Enzyme Activities

2021 ◽  
Author(s):  
Adetunji Alex Adekanmbi ◽  
Laurence Dale ◽  
Liz Shaw ◽  
Tom Sizmur
Keyword(s):  
Enzyme Activity ◽  
Soil Temperature ◽  
Temperature Sensitivity ◽  
Extracellular Enzymes ◽  
Extracellular Enzyme ◽  
Daily Maximum ◽  
Temperature Sensitive ◽  
Intracellular Enzyme ◽  
Temperature Changes ◽  
Som Decomposition

<p>Predicting the pattern of soil organic matter (SOM) decomposition as a feedback to climate change, via release of CO<sub>2</sub>, is extremely complex and has received much attention. However, investigations often do not differentiate between the extracellular and intracellular processes involved and work is needed to identify their relative temperature sensitivities. Samples were collected from a grassland soil at Sonning, UK with average daily maximum and minimum soil temperature of 15 °C and 5 °C. We measured potential activities of β-glucosidase (BG) and chitinase (NAG) (extracellular enzymes) and glucose-induced CO<sub>2 </sub>respiration (intracellular enzymes) at a range of assay temperatures (5 °C, 15 °C, 26 °C, 37<sup>  </sup>°C, and 45 °C). The temperature coefficient Q<sub>10</sub> (the increase in enzyme activity that occurs after a 10 °C increase in soil temperature) was calculated to assess the temperature sensitivity of intracellular and extracellular enzymes activities. Between 5 °C and 15 °C intracellular and extracellular enzyme activities had equal temperature sensitivity, but between 15 °C and 26°C intracellular enzyme activity was more temperature sensitive than extracellular enzyme activity and between 26 °C and 37 °C extracellular enzyme activity was more temperature sensitive than intracellular enzyme activity. This result implies that extracellular depolymerisation of higher molecular weight organic compounds is more sensitive to temperature changes at higher temperatures (e.g. changes to daily maximum summer temperature) but the intracellular respiration of the generated monomers is more sensitive to temperature changes at moderate temperatures (e.g. changes to daily mean summer temperature). We therefore conclude that the extracellular and intracellular steps of SOM mineralisation are not equally sensitive to changes in soil temperature. The finding is important because we have observed greater increases in average daily minimum temperatures than average daily mean or maximum temperatures due to increased cloud cover and sulphate aerosol emission. Accounting for this asymmetrical global warming may reduce the importance of extracellular depolymerisation and increase the importance of intracellular catalytic activities as the rate limiting step of SOM decomposition.</p>

scholarly journals Cytogenetic and molecular localization of tipE: a gene affecting sodium channels in Drosophila melanogaster.

Genetics ◽  
1995 ◽  
Vol 139 (4) ◽  
pp. 1679-1688 ◽  
Author(s):  
G Feng ◽  
P Deák ◽  
D P Kasbekar ◽  
D W Gil ◽  
L M Hall
Keyword(s):  
Drosophila Melanogaster ◽  
Sodium Channel ◽  
Sodium Channels ◽  
Positional Cloning ◽  
Chromosome Region ◽  
Translocation Breakpoint ◽  
Temperature Sensitive ◽  
Binding Studies ◽  
Sodium Permeability ◽  
Cloned Gene

Abstract Voltage-sensitive sodium channels play a key role in nerve cells where they are responsible for the increase in sodium permeability during the rising phase of action potentials. In Drosophila melanogaster a subset of temperature-sensitive paralytic mutations affect sodium channel function. One such mutation is temperature-induced paralysis locus E (tipE), which has been shown by electrophysiology and ligand binding studies to reduce sodium channel numbers. Three new gamma-ray-induced tipE alleles associated with either visible deletions in 64AB or a translocation breakpoint within 64B2 provide landmarks for positional cloning of tipE. Beginning with the flanking cloned gene Ras2, a 140-kb walk across the translocation breakpoint was completed. Germline transformation using a 42-kb cosmid clone and successively smaller subclones localized the tipE gene within a 7.4-kb genomic DNA segment. Although this chromosome region is rich in transcripts, only three overlapping mRNAs (5.4, 4.4, and 1.7 kb) lie completely within the smallest rescuing construct. The small sizes of the rescuing construct and transcripts suggest that tipE does not encode a standard sodium channel alpha-subunit with four homologous repeats. Sequencing these transcripts will elucidate the role of the tipE gene product in sodium channel functional regulation.

scholarly journals Decreased Temperature Sensitivity of Vestigial Gene Expression in Temperate Populations of Drosophila melanogaster

Genes ◽  
2019 ◽  
Vol 10 (7) ◽  
pp. 498
Author(s):  
Voigt ◽  
Erpf ◽  
Stephan
Keyword(s):  
Gene Expression ◽  
Drosophila Melanogaster ◽  
Temperature Sensitivity ◽  
Natural Populations ◽  
Limiting Factor ◽  
Temperature Sensitive ◽  
Thermal Environments ◽  
Wide Range ◽  
Key Factor ◽  
Temperate Climates

Drosophila melanogaster recently spread from its tropical origin in Africa and became a cosmopolitan species that has adapted to a wide range of different thermal environments, including temperate climates. An important limiting factor of temperate climates has probably been their low and varying temperatures. The transcriptional output of genes can vary across temperatures, which might have been detrimental while settling in temperate environments. The reduction of temperature-sensitive expression of functionally important genes to ensure consistent levels of gene expression might have been relevant while adapting to such environments. In this study, we focus on the gene vestigial (vg) whose product is a key factor in wing development. We provide evidence that temperature-sensitivity of vg has been buffered in populations from temperate climates. We investigated temperature-sensitivity of vg gene expression in six natural populations, including four temperate populations (three from Europe and one from high-altitude Africa), and two tropical populations from the ancestral species range. All temperate populations exhibited a lower degree of temperature-induced expression plasticity than the tropical populations.

scholarly journals Site of Action of a Temperature-Sensitive Maternal Effect Mutation in Drosophila Melanogaster

1979 ◽  
Vol 32 (6) ◽  
pp. 597
Author(s):  
NG Brink
Keyword(s):  
Drosophila Melanogaster ◽  
Gene Product ◽  
Maternal Effect ◽  
Nuclear Gene ◽  
Temperature Sensitive ◽  
Pupal Development ◽  
Temperature Changes ◽  
Site Of Action

Previous studies have shown that the D. melanogaster mutant 1(1)1074" is sensitive to temperature changes towards the end of oogenesis, during the sixth to twelfth hour of embryogenesis and again during larval and early pupal development. The 1(1) 1074" gene product resulting from activity of the nuclear gene appears to be important for pupation.

scholarly journals A genetic analysis of hermaphrodite, a pleiotropic sex determination gene in Drosophila melanogaster.

Genetics ◽  
1994 ◽  
Vol 136 (1) ◽  
pp. 195-207
Author(s):  
M A Pultz ◽  
G S Carson ◽  
B S Baker
Keyword(s):  
Drosophila Melanogaster ◽  
Genetic Analysis ◽  
Sex Determination ◽  
Temperature Sensitivity ◽  
Sexual Differentiation ◽  
Regulatory Genes ◽  
Temperature Sensitive ◽  
Partial Loss ◽  
Female Progeny ◽  
Regulatory Cascade

Abstract Sex determination in Drosophila is controlled by a cascade of regulatory genes. Here we describe hermaphrodite (her), a new component of this regulatory cascade with pleiotropic zygotic and maternal functions. Zygotically, her+ function is required for female sexual differentiation: when zygotic her+ function is lacking, females are transformed to intersexes. Zygotic her+ function may also play a role in male sexual differentiation. Maternally, her+ function is needed to ensure the viability of female progeny: a partial loss of her+ function preferentially kills daughters. In addition, her has both zygotic and maternal functions required for viability in both sexes. Temperature sensitivity prevails for all known her alleles and for all of the her phenotypes described above, suggesting that her may participate in an intrinsically temperature-sensitive process. This analysis of four her alleles also indicates that the zygotic and maternal components of of her function are differentially mutable. We have localized her cytologically to 36A3-36A11.

scholarly journals A GENETIC AND BIOCHEMICAL ANALYSIS OF THE TEMPERATURE SENSITIVE, NORMAL-WINGED ALLELES OF THE RUDIMENTARY LOCUS OF DROSOPHILA MELANOGASTER

Genetics ◽  
1977 ◽  
Vol 86 (4) ◽  
pp. 765-777
Author(s):  
Darrel R Falk ◽  
Gary McCaughin ◽  
Thomas Cogley
Keyword(s):  
Drosophila Melanogaster ◽  
High Temperatures ◽  
Temperature Sensitivity ◽  
Biochemical Analysis ◽  
Temperature Sensitive ◽  
Aspartate Transcarbamylase ◽  
Biochemical Characteristics ◽  
Pyrimidine Synthesis ◽  
Leaky Mutants

ABSTRACT The genetic and biochemical characteristics of a particular class of mutants at the rudimentary locus are described. The mutants are pyrimidine auxotrophs, like classical rudimentary alleles, but they are unique in that they do not alter the size or shape of the wing (Falk and Nash 1974b). Aspartate transcarbamylase and dihydroorotase activities have been measured in seven different normal-winged mutants, and the results indicate that these strains are enzymologically "leaky" mutants. Previous studies have shown that three genetic functions (corresponding to the first three enzymes of pyrimidine synthesis) are associated with the rudimentary locus. Four of the seven mutants appear to affect all three of these functions. Each of the four is temperature sensitive, and a biochemical analysis of the temperature sensitivity of one of these mutants, (r)pyr1-3, suggests that a process affecting the synthesis or assembly of these enzymes is altered at high temperatures.

TEMPERATURE-SENSITIVE MUTATIONS IN DROSOPHILA MELANOGASTER.: II. FREQUENCY AMONG SECOND CHROMOSOME RECESSIVE LETHALS INDUCED BY ETHYL METHANESULFONATE

1968 ◽  
Vol 10 (2) ◽  
pp. 412-420 ◽  
Author(s):  
David Baillie ◽  
David T. Suzuki ◽  
Mary Tarasoff
Keyword(s):  
Drosophila Melanogaster ◽  
Temperature Sensitivity ◽  
Ethyl Methanesulfonate ◽  
Temperature Sensitive ◽  
Chromosome 2 ◽  
Genetic Studies ◽  
Recessive Lethal

Recessive lethal and semilethal mutations induced in chromosome 2 by ethyl methanesulfonate were screened for temperature-sensitivity. Mutants which survive at 17 °C but die at 29° were recovered. At 0.005M EMS, 37.5% of the treated chromosomes were found to be lethal or semilethal from which it is estimated that 10.9% of all EMS-induced lethals are ts. This class of conditional lethals promises to be a useful tool in genetic studies.

TEMPERATURE-SENSITIVE MUTATIONS IN DROSOPHILA MELANOGASTER: XX. LETHALITY DUE TO TRANSLOCATIONS

1974 ◽  
Vol 16 (3) ◽  
pp. 579-592 ◽  
Author(s):  
Thomas C. Kaufman ◽  
David T. Suzuki
Keyword(s):  
Drosophila Melanogaster ◽  
Temperature Sensitivity ◽  
Position Effect ◽  
Temperature Sensitive ◽  
Crossing Over ◽  
Lethal Mutations ◽  
New Type ◽  
Γ Ray ◽  
Developmental Analysis ◽  
Ts Mutations

In a group of 10 γ-ray-induced temperature-sensitive (ts) lethal mutations on the X chromosome of Drosophila melanogaster, three were found to inhibit crossing over on this element. Subsequent studies showed that these three ts lethal mutations are associated with X [Formula: see text] autosome translocations. Developmental analysis has revealed that the patterns of temperature-sensitivity and lethality are similar to those found in other ts mutations. One of the mutations (T(X;2)X9ts) is unique, however, in that only males exhibit temperature-sensitive lethality while homozygous females are unaffected by a change in temperature. It is proposed that these three mutations may be exhibiting some new type of "position effect".

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