FlyBase Allele Report: Dmel\trp[2]

General Information

Symbol

Dmel\trp²

Species

D. melanogaster

Name

FlyBase ID

FBal0017156

Feature type

allele

Associated gene

Dmel\trp

Associated Insertion(s)

Carried in Construct

Also Known As

trp^P301, trp³⁰¹

Key Links

Allele class

loss of function allele

Mutagen

ethyl methanesulfonate

Nature of the Allele

Allele class

loss of function allele

(Leung et al., 2000, Reuss et al., 1997, Niemeyer et al., 1996, Pollock et al., 1995)

Mutagen

ethyl methanesulfonate

Progenitor genotype

Cytology

Description

Mutations Mapped to the Genome

Curation Data

Type

Location

Additional Notes

References

Variant Molecular Consequences

Associated Sequence Data

DDBJ / EMBL / GenBank

DNA sequence

Protein sequence

UniProtKB/Swiss-Prot

UniProtKB/TrEMBL

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 )

Disease-implicated variant(s)

Phenotypic Data

Phenotypic Class

abnormal neurophysiology

(Popescu et al., 2006, Reuss et al., 1997)

abnormal neurophysiology, with trp^S982A.hsp70

(Popescu et al., 2006)

abnormal smell perception | dominant

(Stortkuhl et al., 1999)

abnormal visual behavior

(Leung et al., 2000, Li et al., 1999, Reuss et al., 1997)

abnormal visual behavior | recessive

(Shieh and Zhu, 1996)

Phenotype Manifest In

antenna

(Stortkuhl et al., 1999)

photoreceptor

(Reuss et al., 1997)

photoreceptor cell & axon

(Niemeyer et al., 1996)

photoreceptor neuron

(Leung et al., 2000, Li et al., 1999)

retina

(Popescu et al., 2006)

retina, with trp^S982A.hsp70

(Popescu et al., 2006)

Detailed Description

Statement

Reference

In red-eyed trp² homozygous flies flies dark-adapted for 2 minutes, the electro-retinogram (ERG) response to 2 second white-light stimulation displays the initial fast depolarization seen in wild-type, but, unlike wild-type depolarisation is not maintained during stimulation and the membrane potential returns gradually to baseline following depolarisation. This phenotype is only partially rescued by trp^S982A.hsp70 : maintenance of depolarisation during stimulation is completely rescued, but recovery of polarisation following the end of stimulation is slower than in wild-type. However, rescue is complete if only low-light stimulation is used.

(Popescu et al., 2006)

The maximum rate of capa stimulated fluid transport in Malpighian tubules from trp² animals is not significantly different from that of wild-type tubules, and the basal rate of secretion is also unaffected.

(Macpherson et al., 2005)

ERG shows no sustained response during prolonged light stimulation, reduced peak amplitude and longer than normal response latency.

(Leung et al., 2000)

The phenotypes of inaF^P106x, trp⁹ and trp² are similar with respect to rapid time course of decay of potential during stimulus, V-logI curves, latency and recovery of response from a previous stimulation.

(Li et al., 1999)

The olfactory response of naive trp² flies to isoamyl acetate (IAA) and benzaldehyde is normal. However, trp² flies are severely defective in olfactory adaptation, when tested with either odour as the adapting stimulus in a T maze. The effect on adaptation is dominant. The electroantennogram (EAG) of naive trp² flies in response to a 10^-1 dilution of IAA is no different from that of wild-type flies. The recovery of the EAG after exposure to IAA is faster in trp² flies than in wild-type flies. This quicker recovery is dominant. trp² flies also show abnormal cross-adaptation in the antenna; pre-exposure of flies to IAA causes a major decline in the response to benzaldehyde, however at the earliest time point examined, trp² flies show a greater response to benzaldehyde than wild-type, as if adaptation is less complete than wild-type or as if some degree of recovery has occurred. This effect is dominant.

(Stortkuhl et al., 1999)

Except in double mutants with trpl³⁰², trp¹ and trp² are phenotypically indistinguishable with respect to reversal potential and channel noise. E_rev in mutant photoreceptors shows a large negative shift compared to wild type. Light sensitive conductance is more permeable to Cs⁺ than Na⁺ (as opposed to the case for wild type where Na⁺ is more permeable than Cs⁺. Permeability to Li⁺ is roughly the same in wild type, trpl³⁰² and trp² mutants. Measurements of the reversal potential under conditions of low external calcium reveal the high Ca²⁺ selectivity of the trp-dependent channels. In general the permeability of mutant photoreceptors to Ca²⁺, Na⁺, Li⁺, Ba²⁺, Mg²⁺ and Mn²⁺ is lower than that for wild type. Shows no biphasic reversal potential behaviour with lowered external calcium. Estimated single channel conductance is 35pS. Light sensitive conductance is inhibited by Ca²⁺.

(Reuss et al., 1997)

trp² flies have an abnormal electroretinogram (ERG) phenotype.

(Tsunoda et al., 1997)

Ca²⁺ influx in the mutant light-sensitive channels is reduced by a factor of about 2.5.

(Hardie, 1996)

The step response is a transient, biphasic reflectance change, the peak amplitude of the biphasic pigment migration response is severely reduced compared to the amplitude of the monophasic response of wild type. The light sensitivity of the pigment migration is severely reduced compared to wild type. The pulse response is shortened compared to wild type and decay of the response is delayed.

(Hofstee and Stavenga, 1996)

Double mutants of inaD¹ with trp² show the same ERG phenotype as trp² alone.

(Shieh and Zhu, 1996)

Relieves the Mg²⁺ block on the light-sensitive current in photoreceptors.

(Hardie and Mojet, 1995)

The reversal potential (E_rev)of the light-induced current is smaller than wild-type at both 19^oC and 25^oC. The amplitude of the rundown current (RDC) is much smaller than wild-type in heterozygotes, and undetectable in homozygotes.

(Pollock et al., 1995)

External Data

Linkouts

Interactions

Show genetic interaction network for Enhancers & Suppressors

Phenotypic Class

Enhancer of

Statement

Reference

trp² is an enhancer of abnormal visual behavior phenotype of trpl³⁰²

(Li et al., 1999)

Suppressor of

Statement

Reference

trp² is a suppressor | partially of increased cell death phenotype of ninaE^pp100

(Iakhine et al., 2004)

Other

Statement

Reference

trp², trpl³⁰² has abnormal visual behavior phenotype

(Leung et al., 2000, Reuss et al., 1997)

Phenotype Manifest In

Enhancer of

Statement

Reference

trp² is an enhancer of photoreceptor neuron phenotype of trpl³⁰²

(Li et al., 1999)

Suppressor of

Statement

Reference

trp² is a suppressor | partially of retina phenotype of ninaE^pp100

(Iakhine et al., 2004)

trp² is a suppressor of phenotype of rdgA¹

(Raghu et al., 2000)

trp² is a suppressor of ommatidium & microvillus phenotype of rdgA¹

(Raghu et al., 2000)

trp²/trpl³⁰² is a suppressor of ommatidium & microvillus phenotype of rdgA¹

(Raghu et al., 2000)

trp² is a suppressor of ommatidium phenotype of rdgA¹

(Raghu et al., 2000)

trp²/trpl³⁰² is a suppressor of ommatidium phenotype of rdgA¹

(Raghu et al., 2000)

Other

Statement

Reference

trp², trpl³⁰² has photoreceptor neuron phenotype

(Leung et al., 2000)

trp², trpl³⁰² has photoreceptor phenotype

(Reuss et al., 1997)

trp², trpl³⁰² has photoreceptor cell & axon phenotype

(Niemeyer et al., 1996)

Additional Comments

Genetic Interactions

Statement

Reference

In ninaE^pp100, trp² double mutants, retinal degeneration is delayed but not prevented, relative to ninaE^pp100 single mutants.

(Iakhine et al., 2004)

ERG light responses of trpl³⁰²,inaD¹ and trpl³⁰²,trp² are small and transient, but the response amplitude of trpl³⁰²,inaD¹ is significantly smaller than that of trpl³⁰²,trp². Similarly, refractory period and response latency defects are more severe for trpl³⁰²,inaD¹ than for trpl³⁰²,trp².

(Leung et al., 2000)

Ommatidial appearance of rdgA¹ is largely restored to wild type by mutants at the trp locus, though defects detectable at the EM level remain. These residual defects are suppressed in the triple mutant with trpl³⁰². These anatomical rescue effects are paralleled by rescue of electrophysiological defects of rdgA¹ mutants. Double rdgA¹, trp mutants show age dependent retinal degeneration.

(Raghu et al., 2000)

Double mutant analysis comparing the receptor potentials of trpl³⁰² with inaF^P106x; trpl³⁰² or trp²; trpl³⁰² or trp⁹; trpl³⁰² showed that the effects of inaF^P106x are as severe as those of trp² and are specific to the trp channel.

(Li et al., 1999)

trpl³⁰²; trp² double mutants are almost blind, as judged by response to saturating ultraviolet flashes and ERG recordings.

(Reuss et al., 1997)

Whole-cell patch-clamp recordings of photoreceptors display responses with reduced amplitudes and defective kinetics. trpl³⁰²; trp² mutants display a dramatic loss of responsiveness, the residual current is due to a small amount of functional trp channel. trpl³⁰²; trp² mutants exhibit a dramatic bump phenotype. Reintroduction of trpl^hs.PN to trpl³⁰²; trp² mutants rescues the defect and restores visual physiology. Photoreceptor cells produce quantum bumps (the unitary event of a single photon) with a mean amplitude less than 30% of wild type.

(Niemeyer et al., 1996)

Xenogenetic Interactions

Statement

Reference

Complementation and Rescue Data

Rescued by

trp² is rescued by trp^hsp70.PP

(Popescu et al., 2006)

Partially rescued by

trp² is partially rescued by trp^S982A.hsp70

(Popescu et al., 2006)

Comments

trp^hsp70.PP completely rescues the ERG response of red-eyed trp² homozygous flies, dark-adapted for 2 minutes, to a 2 second white-light stimulation.

(Popescu et al., 2006)

Images (0)

Mutant

Wild-type

Stocks (0)

Notes on Origin

Discoverer

Pak.

External Crossreferences and Linkouts ( 0 )

Synonyms and Secondary IDs (4)

Reported As

Symbol Synonym

trp²

trp³⁰¹

(Vasiliauskas et al., 2011, Sanxaridis and Tsunoda, 2010, Satoh et al., 2010, Popescu et al., 2006, Macpherson et al., 2005, Iakhine et al., 2004, MacPherson et al., 2000, Raghu et al., 2000, Chyb et al., 1999, Hardie et al., 1997, Klemens and John, 1997, Reuss et al., 1997, Tsunoda et al., 1997, Hardie, 1996, Niemeyer et al., 1996)

trp^P301

(Mecklenburg et al., 2010, Leung et al., 2000, Liu et al., 2000, Yoon et al., 2000, Li et al., 1999, Stortkuhl et al., 1999, Chevesich et al., 1997, Reuss et al., 1997, Hofstee and Stavenga, 1996, Shieh and Zhu, 1996, Hardie and Mojet, 1995, Pollock et al., 1995)

trp^p301

(Cheng and Nash, 2007, Stortkuhl et al., 1999, Shieh et al., 1997, Störtkuhl et al., 1997)

Name Synonyms

Secondary FlyBase IDs

References (30)

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