Open Close
General Information
Symbol
Dmel\Ir76b1
Species
D. melanogaster
Name
FlyBase ID
FBal0285654
Feature type
allele
Associated gene
Associated Insertion(s)
Carried in Construct
Allele class
Nature of the Allele
Allele class
Mutations Mapped to the Genome
 
Type
Location
Additional Notes
References
Associated Sequence Data
DNA sequence
Protein sequence
 
 
Cytology
Nature of the lesion
Statement
Reference

Imprecise excision of the progenitor insertion, resulting in a deletion of Ir76b sequences.

Expression Data
Reporter Expression
Additional Information
Statement
Reference
 
Marker for
Reflects expression of
Reporter construct used in assay
Human Disease Associations
Disease Ontology (DO) Annotations
Models Based on Experimental Evidence ( 0 )
Disease
Evidence
References
Modifiers Based on Experimental Evidence ( 0 )
Disease
Interaction
References
Comments on Models/Modifiers Based on Experimental Evidence ( 0 )
 
Phenotypic Data
Phenotypic Class
Phenotype Manifest In
Detailed Description
Statement
Reference

Ir76b1 mutant flies do not show significant changes in the expected avoidance response to food laced with different acids (5% acetic acid, 5% glycolic acid, 10% citric acid, 20% lactic acid, 5% tartaric acid, 2% propionic acid, 2% butyric acid, or 10mM HCl), as compared to controls. GRNs enervating S6 and S10 sensilla do not show changes in the responses (frequency of spikes) to 1% acetic acid, 1% glycolic acid, 1% tartaric acid, 5% citric acid, 1% propionic acid, 1% butyric acid, 10mM HCl, and 20% lactic acid, as compared to controls.

Ir76b1 hetero- and homozygotes show the expected increased food consumption induced by dietary amino acids, as observed in controls.

Adults with homozygous Ir76b1 have proboscis extension rates that are significantly reduced in response to fatty acids and significantly increased in response to sucrose, compared to controls.

Ir76b1/Ir76b1 and Ir76b1/Ir76b2 adult females have significantly reduced preference for oviposition on acid-containing medium, compared to controls.

Ir76b1/Ir76b1 mutant females exhibit a significant reduction in feeding preference index for yeast extract, but no significant change in feeding preference index for sucrose, as compared to wild type.

Ir76b1 homozygous, but not heterozygous, larvae have significantly reduced attraction to appetitive concentrations of Asp, Glu and Phe, but not Cys, amino acids, compared to controls; food intake in the presence of high alanine concentrations, but not in the presence of caffeine, is significantly increased, compared to controls.

In olfactory preference assays for polyamines, Ir76b1/Ir76b1 (but not Ir76b1/+) flies show a significant decrease in their attraction to putrescine or cadaverine, as compared to wild type. Ir76b1/Ir76b1 mutants also show a significant decrease in neuronal activity of the IR41a-neuron-innervated glomerulus, and regions of the subesophageal zone, in response to putrescine odor, as compared to heterozygous controls. Ir76b1/Ir76b1 females display a loss of aversion to oviposit on polyamine-rich substrate (plain, sugar-free 1% agarose supplemented with either putrescine or cadaverine) versus non-supplemented substrate, in contrast to wild type flies, instead showing no preference for either substrate. Ir76b1/Ir76b1 mutants show a significant decrease in neuronal activity of the subesophageal zone in response to NaCl[[2]] stimulation, as compared to controls.

Ir76b1 mutant adults show normal preference for less solid sucrose-agarose food than a harder one (higher agarose conc., same sucrose content) one in a two-way food choice assay.

L4 sensilla of mutant flies show a normal response to each of 50mM KCl, 50mM sucrose, water and to a number of butter tastants (0.1mM denatonium, 0.1mM berberine, 6mM caffeine, 0.1mM strychnine and 0.1mM quinine).

The firing of L6 sensilla in response to low salt (50mM NaCl) is impaired in mutant flies. The electrophysiological response of high salt gustatory receptor neurons in both the S4 and S8 sensilla in response to 500mM NaCl is normal.

Expression of Ir76bScer\UAS.cZa under the control of Scer\GAL4Gr5a.PUn in a Ir76b1 background results in the Gr5a gustatory receptor neurons in the L2 sensilla showing a robust electrophysiological response to NaCl.

Mutant flies show severe defects in attraction to low salt concentrations, while aversion to high salt concentrations is normal. There is a significant decrease in the frequency of action potentials elicited by 50mM NaCl in the L4 sensilla compared to wild type, while the electrophysiological response of the S6 sensilla to 50mM NaCl is normal. The firing frequency of gustatory receptor neurons in the L4 sensilla is reduced compared to wild type across all salt concentrations from 1 to 1000mM.

Expression of Ir76bScer\UAS.cZa under the control of Scer\GAL4Gr5a.PUn in a Ir76b1 background results in the Gr5a gustatory receptor neurons in the L2 sensilla showing a robust electrophysiological response to NaCl. These sensilla show no response to NMDGCl (indicating that the response to 50Mm NaCl is due to Na[+]). The response of these sensilla to 50mM sucrose is not significantly different from wild type.

External Data
Interactions
Show genetic interaction network for Enhancers & Suppressors
Phenotypic Class
Phenotype Manifest In
Additional Comments
Genetic Interactions
Statement
Reference
Xenogenetic Interactions
Statement
Reference
Complementation and Rescue Data
Comments

Expression of Ir76bScer\UAS.cZa under the control of Scer\GAL4Ir76b.916 or Scer\GAL4Ir41a.2474 restores the olfactory preference for putrescine in Ir76b1/Ir76b1 mutant flies. Expression of Ir76bScer\UAS.cZa under the control of Scer\GAL4Ir76b.916, but not Scer\GAL4Ir41a.2474 or Scer\GAL4Gr66a.PU, restores the oviposition aversion to putrescine-containing substrate shown by female Ir76b1/Ir76b1 mutants.

Expression of Ir76bScer\UAS.cZa under the control of Scer\GAL4Ir76b.1.5 rescues the behavioral and electrophysiological defects seen in Ir76b1 flies in response to low salt concentrations.

Expression of Ir76bScer\UAS.cZa under the control of Scer\GAL4Gr5a.PUn rescues the defect in low-salt preference which is seen in Ir76b1 flies.

Images (0)
Mutant
Wild-type
Stocks (1)
Notes on Origin
Discoverer
External Crossreferences and Linkouts ( 0 )
Synonyms and Secondary IDs (2)
References (13)