FlyBase Allele Report: Dmel\comt[4]

General Information

Symbol

Dmel\comt⁴

Species

D. melanogaster

Name

FlyBase ID

FBal0001758

Feature type

allele

Associated gene

Dmel\comt

Associated Insertion(s)

Carried in Construct

Also Known As

comt^ST17

Key Links

Genomic Maps

JBrowse

Allele class

Mutagen

ethyl methanesulfonate

Nature of the Allele

Allele class

Mutagen

ethyl methanesulfonate

(Pallanck et al., 1995)

Progenitor genotype

Cytology

Description

Amino acid replacement: G274E.

(Kawasaki and Ordway, 2000)

Single missense mutation due to at GC to AT transition.

(Pallanck et al., 1995)

Mutations Mapped to the Genome

Curation Data

Type

Location

Additional Notes

References

point_mutation

X:13,260,298..13,260,298 [+]

Nucleotide change:

G13260298A

Amino acid change:

G274E | comt-PA; G274E | comt-PB

Reported amino acid change:

G274E

Comment:

Site of nucleotide substitution in mutant inferred by FlyBase based on reported amino acid change.

(Kawasaki and Ordway, 2000, Pallanck et al., 1995)

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 ( 1 )

Disease

Evidence

References

model of Parkinson's disease

CEA

(Babcock et al., 2015)

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 locomotor behavior | adult stage | heat sensitive

(Babcock et al., 2015)

abnormal neuroanatomy | adult stage | heat sensitive

(Babcock et al., 2015)

abnormal neuroanatomy | heat sensitive

(Littleton et al., 2001)

abnormal neurophysiology | heat sensitive

(Kawasaki and Ordway, 2009, Littleton et al., 2001, Kawasaki et al., 1998, Littleton et al., 1998)

abnormal starvation stress response | adult stage

(Babcock et al., 2015)

abnormal visual behavior | heat sensitive

(Littleton et al., 1998)

lethal - all die before end of P-stage | recessive | heat sensitive

(Golby et al., 2001)

paralytic

(Siddiqi and Benzer, 1976)

paralytic | heat sensitive

(Wang et al., 2004, Golby et al., 2001, Littleton et al., 2001, Littleton et al., 1998, Pallanck et al., 1995)

paralytic | heat sensitive (with comt^clp)

(Sanyal and Krishnan, 2001)

paralytic | recessive | heat sensitive

(Dellinger et al., 2000)

short lived | heat sensitive

(Babcock et al., 2015)

some die during pharate adult stage | recessive | heat sensitive

(Golby et al., 2001)

uncoordinated | larval stage | recessive

(Golby et al., 2001)

Phenotype Manifest In

Golgi stack

(Kondylis et al., 2001)

neuropil | adult stage | heat sensitive

(Babcock et al., 2015)

optic cartridge & synaptic vesicle

(Littleton et al., 1998)

retina | heat sensitive

(Littleton et al., 1998)

synapse

(Littleton et al., 2001)

synaptic vesicle | heat sensitive

(Kawasaki et al., 1998)

Detailed Description

Statement

Reference

comt⁴/comt⁴ mutants exhibit severely reduced lifespans when reared at 29[o]C, and a milder reduced lifespan phenotype when reared at 22[o]C; display neurodegeneration, as assessed by presence of vacuoles in the neuropil after 48-hr exposure to 29[o]C; display normal climbing ability when reared at 22[o]C, but loss of climbing ability after shifting to 29[o]C; and decreased survival during prolonged starvation during adulthood at 22[o]C, as compared with wild type flies.

(Babcock et al., 2015)

At the restrictive temperature of 33[o]C, comt⁴ mutants exhibit a wild-type excitatory postsynaptic current (EPSC) in response to stimulus. However, subsequent stimulation produces a marked activity-dependent reduction in EPSC amplitude relative to wild-type.

At the restrictive temperature of 33[o]C, comt⁴ synapses exhibit a two-component recovery time course indistinguishable from that of wild-type.

After 5Hz stimulation at 33[o]C, Snap25^ts DLM neuromuscular synapses exhibit marked activity-dependent reduction in EPSC amplitude with respect to wild-type. The EPSC amplitude declines progressively over 100 stimuli to 21% of the first amplitude. The initial time course of depression closely resembles that of wild-type over the first five stimuli. Recovery in comt⁴ exhibits a similar time constant to the slow component in PP experiments.

(Kawasaki and Ordway, 2009)

comt⁴ mutants exposured to 38^oC exhibit a delay before paralysis.

(Wang et al., 2004)

Hemizygous male larvae take much longer than wild type to roll from lying on their dorsal surface to their ventral surface.

(Golby et al., 2001)

Wild-type larvae incubated at 37^oC show conversion of larval clusters of vesicles and tubules in the Golgi areas of leg and wing discs into Golgi cisternae. This formation of Golgi cisternae is blocked in homozygous female and hemizygous male comt⁴ larvae incubated at 37^oC (which have been fed ecdysone) and is also blocked in comt⁴ discs incubated in vitro at 37^oC (in the presence of ecdysone).

(Kondylis et al., 2001)

Electroretinograms taken from the retina at 38^oC reveal losses of on/off transients in mutants. Retinal axon terminals are filled with synaptic vesicles that have not fused with the membrane.

(Littleton et al., 2001)

The action potentials of the dorsal longitudinal flight muscle (DLM) are indistinguishable from wild-type at the permissive temperature (20^oC). At the restrictive temperature, the first stimulus produces a wild-type action potential, but subsequent stimuli result in a reduction and then loss of the DLM action potential. A slowing of the synaptic current kinetics is seen. The number of docked vesicles per active zone is higher than wild-type in the neuromuscular synapses of the coxal muscles (at the restrictive temperature).

(Kawasaki et al., 1998)

In ERG assay, mutants lose the on/off transients at 38^oC, though over a slower time course than for Syx1A^3-69. Recovery of transients at 20^oC is slower than for Syx1A^3-69. ERG phenotypes correlate with paralytic phenotypes: time course of paralysis and recovery for Syx1A mutants is more rapid than for comt mutants. Ultrastructural studies reveal that the number of synaptic vesicles in photoreceptor terminals in the optic cartridge is increased. Clear inreases occur in the number of vesicles clustered round T-bars. Number of docked vesicles is increased compared to wild type.

(Littleton et al., 1998)

Paralysis normally occurs within 1-2 minutes of exposure to 38^oC. comt⁴ flies bearing P{hsp70-NSF} exposed to heat shock, followed by one day recovery, are highly resistant to exposure to 38^oC.

(Pallanck et al., 1995)

Reversible heat induced paralysis.

(Siddiqi and Benzer, 1976)

External Data

Linkouts

Interactions

Show genetic interaction network for Enhancers & Suppressors

Phenotypic Class

Enhanced by

Statement

Reference

comt⁴ has paralytic | recessive | heat sensitive phenotype, enhanceable by ovr¹

(Dellinger et al., 2000)

comt⁴ has paralytic | heat sensitive phenotype, enhanceable by cac^S

(Dellinger et al., 2000)

Suppressed by

Statement

Reference

comt⁴ has paralytic | heat sensitive phenotype, suppressible by Scer\GAL4^elav-C155/Nsf2^UAS.cGa

(Golby et al., 2001)

comt⁴ has abnormal neuroanatomy | heat sensitive phenotype, suppressible by shi¹

(Littleton et al., 2001)

NOT suppressed by

Statement

Reference

comt⁴ has short lived | heat sensitive phenotype, non-suppressible by sei²/sei²

(Babcock et al., 2015)

Other

Statement

Reference

comt⁴, para^ts1 has paralytic phenotype

(Littleton et al., 2001)

comt⁴, para^ts1 has paralytic | heat sensitive phenotype

(Littleton et al., 2001)

Phenotype Manifest In

Suppressed by

Statement

Reference

comt⁴ has synapse | heat sensitive phenotype, suppressible by shi¹

(Littleton et al., 2001)

Additional Comments

Genetic Interactions

Statement

Reference

sei²/sei² does not significantly change the severity of the shortened lifespan phenotype of comt⁴/comt⁴ mutants at 29[o]C.

(Babcock et al., 2015)

cac^TS2 comt⁴ double mutant males generate song pulses whose intrapulse cycle (CPP) values are within the normal range.

(Chan et al., 2002)

comt⁴, para^ts1 double mutant animals exposed to 38^oC for 5 minutes show a rapid recovery from the paralysis phenotype when returned to the permissive temperature. After rapid recovery and normal behaviour, these flies suddenly re-paralyse several minutes later at the permissive temperature. Retinal axon terminals in comt⁴ shi¹ are devoid with synaptic vesicles and show an increase in larger vacuolar-type structures.

(Littleton et al., 2001)

ovr¹ accelerates the paralysis observed in comt⁴ animals at 36^oC (the time for 50% paralysis is reduced). cac^S comt⁴ double mutants show faster paralysis than comt⁴ single mutants at both 36^o and 38^oC.

(Dellinger et al., 2000)

Xenogenetic Interactions

Statement

Reference

Complementation and Rescue Data

Rescued by

comt⁴ is rescued by Scer\GAL4^Appl.G1a/comt^UAS.Tag:FLAG

(Kawasaki and Ordway, 2009)

comt⁴ is rescued by comt^hs.PP

(Kondylis et al., 2001)

comt⁴ is rescued by comt^hs.PP

(Kawasaki et al., 1998)

Partially rescued by

comt⁴ is partially rescued by Scer\GAL4^elav-C155/comt^UAS.cGa

(Golby et al., 2001)

Comments

Images (0)

Mutant

Wild-type

Stocks (1)

Bloomington

92840

comt⁴

Notes on Origin

Discoverer

Siddiqi and Benzer.

Comments

The G274E mutation alone is responsible for the temperature sensitive paralytic phenotype of comt⁴.

(Kawasaki and Ordway, 2000)

Results from response to cervical stimulation, intracellular recordings of flight muscles and direct excitability of muscle cannot distinguish if the mutant phenotype is due to a slowing of nerve induction, delayed transmitter release at the nerve terminal or a defect in muscle response to chemical excitation.

(Siddiqi and Benzer, 1976)

External Crossreferences and Linkouts ( 0 )

Synonyms and Secondary IDs (6)

Reported As

Symbol Synonym

ST17

(Tolar and Pallanck, 1998)

comt 17

(Kondylis et al., 2001)

comt⁴

comt^ST17

(Bademosi et al., 2017, Babcock et al., 2015, Yu et al., 2011, Kawasaki and Ordway, 2009, Wang et al., 2004, Chan et al., 2002, Littleton et al., 2001, Dellinger et al., 2000, Kawasaki and Ordway, 2000, Kawasaki et al., 1998, Littleton et al., 1998, Siddiqi and Benzer, 1976)

comt^st17

(Sanyal and Krishnan, 2001, Pallanck et al., 1995)

dNSF1^comt-st17

(Golby et al., 2001)

Name Synonyms

Secondary FlyBase IDs

References (17)

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