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General Information
Symbol
Dmel\slo1
Species
D. melanogaster
Name
FlyBase ID
FBal0015706
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
 
 
Progenitor genotype
Cytology

Polytene chromosomes normal.

Nature of the lesion
Statement
Reference
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

Air puff-triggered flight initiation success is dramatically reduced in slo1 mutants.

Homozygous third instar larvae show a significant increase in bouton size at the neuromuscular junction compared to controls.

The excitatory junctional current amplitude at the neuromuscular junction is reduced in mutants compared to controls. The EJC response of mutant neuromuscular junctions under low conditions (pH 6.1) is not different to wild-type.

slo1 mutants display abundant small boutons, termed 'satellites', budding from the larger primary boutons along the branch axis. Such aberrant outgrowth is found at both type Ib and Is neuromuscular junctions in different muscles, e.g. 6/7 and 4. Upon closer examination, two distinct types of satellites are observed, one without a clear constriction between satellites and primary boutons, resembling yeast budding (type B satellites) and the other with a short but clear constriction or 'neck' (type M satellites). Type B satellites are more abundant than type M satellites in these mutants. There is also an overall increase in synaptic bouton number and terminal branching in these mutants.

Exposure to high temperatures (29[o]C) for 2 hours during development fails to induce significant morphological changes in synaptic growth in slo1 mutants. However, numbers of both B- and M-type satellites are drastically reduced after 5 hours of high temperature. Wild-type synapses do not exhibit this behaviour. 5 hour heat treatment also increases the number of branches seen in slo1 mutants.

Larvae heterozygous for slo1 show increases in the numbers of type-B and -M satellites, mature boutons, and branch segments, comparable to homozygous mutants.

Around one third of slo1 flies are arrhythmic in LD, while over half are rhythmic in DD. This arrhythmicity is more severe in slo1/slo4 transheterozygotes.

The rate of habituation of the giant fiber escape pathway is markedly reduced in slo1 flies compared to wild-type. The refractory period of the long-latency response is shorter than normal. The short-latency response of the tergotrochanteral muscle is delayed.

Homozygous males produce very low amplitude courtship songs with long interpulse intervals, and low interpulse frequency and cycles per pulse values compared to wild-type males. Isolated putative pulses, usually monocyclic signals, often occur. Males show many courtship wing extensions without actually producing audible sound. The interpulse frequency of heterozygous males is significantly lower than in wild-type males at 25oC, although other courtship song parameters of heterozygous males are normal. slo1/Df(3R)slo3 males show an intermediate courtship song phenotype between slo1 and Df(3R)slo3 homozygous males.

Homozygotes show increased sensitivity to halothane, chloroform and trichloroethylene in an inebriometer assay (an assay of geotactic and postural behaviour) compared to wild-type flies.

In combination with DAP or Sh14, electrotonically evoked synaptic currents show delay before transmitter release and decrease in onset slope when assayed in third instar larvae.

The Ca2+-activated fast K+ current (ICF) is eliminated in larval muscle fibres.

External Data
Interactions
Show genetic interaction network for Enhancers & Suppressors
Phenotypic Class
Suppressed by
Statement
Reference
NOT suppressed by
Statement
Reference

slo1 has neuroanatomy defective phenotype, non-suppressible by mlenap-ts1

slo1 has neuroanatomy defective phenotype, non-suppressible by dlg17

Phenotype Manifest In
Suppressed by
Statement
Reference

slo1 has NMJ bouton | supernumerary phenotype, suppressible by sei1

slo1 has NMJ bouton | supernumerary phenotype, suppressible by rut1

slo1 has neuromuscular junction phenotype, suppressible by rut1

slo1 has NMJ bouton | supernumerary phenotype, suppressible by dncM14

slo1 has neuromuscular junction phenotype, suppressible by sei1

slo1 has neuromuscular junction phenotype, suppressible by dncM14

slo1 has NMJ bouton | supernumerary phenotype, suppressible by Fas2e76

slo1 has NMJ bouton | supernumerary phenotype, suppressible by dlg17

slo1 has neuromuscular junction phenotype, suppressible by dlg17

slo1 has NMJ bouton | supernumerary phenotype, suppressible by Ca-α1DAR66

NOT suppressed by
Statement
Reference

slo1 has NMJ bouton | supernumerary phenotype, non-suppressible by mlenap-ts1

slo1 has neuromuscular junction phenotype, non-suppressible by mlenap-ts1

slo1 has neuromuscular junction phenotype, non-suppressible by Fas2e76

Additional Comments
Genetic Interactions
Statement
Reference

When compared with single mutants, the combined mutational effects of sei1/slo1 are not simply additive, with a further enhancement of some slo, but not sei phenotypes. Satellite abundance is less extreme in sei1/slo1 double mutants compared to sei1 mutants. There is a slight, but not significant, reduction in the numbers of both types B and M satellites. In contrast, the numbers of type M (but not type B) satellites and mature boutons are significantly greater in double mutants compared to slo single mutants.

The frequency of satellite formation in Fas2e76; slo1 double mutants is comparable to slo1 single mutants. Overall bouton number is slightly reduced in these double mutants. However, a similar reduction is seen in Fas2e76 mutants.

dlg17/slo1 mutants exhibit reduced levels of type B and type M satellites, close to wild-type levels, compared to slo1 single mutants. This reduction correlates with reduced levels of mature boutons and with simpler branching patterns.

A Ca-α1DAR66 mutant background suppresses both type B and type M satellites in Ca-α1DAR66; slo1 double mutants nearly to wild-type levels. Such suppression in satellite formation leads to the morphology of these double mutants to resemble Ca-α1DAR66 single mutants.

Overexpression of dlg1WT.Scer\UAS.T:Avic\GFP-EGFP in the developing muscle under the control of Scer\GAL4Mef2.247 induces a more pronounced reduction in type B satellites (small boutons) in slo1 mutants. As a result, the numbers of remaining type B and type M satellites becomes similar, and there are fewer satellites in total. The number of mature boutons is significantly enhanced in slo1 larvae expressing post-synaptic dlg1WT.Scer\UAS.T:Avic\GFP-EGFP.

Despite their abundance in slo1 single mutants, levels of both type B and type M satellites are suppressed in rut1; slo1 double mutants to wild-type levels, along with a slight reduction in mature bouton number.

A mlenap-ts1 mutant background does not affect synaptic satellite growth in slo1 mutants.

A dncM14 mutant background severely suppresses the frequency of type B and type M satellites (small boutons) in dncM14; slo1 double mutants.

Pre-synaptic expression of dncScer\UAS.cCa (under the control of Scer\GAL4elav-C155 in a slo1 background does not influence satellite bouton number.

Post-synaptic expression of dncScer\UAS.cCa (under the control of Scer\GAL4C164 in a slo1 background suppresses the number of both type M and type B satellites. However, the number of mature boutons remains higher in these mutants.

Xenogenetic Interactions
Statement
Reference
Complementation and Rescue Data
Comments

The flight behaviour defective phenotype of slo1 is complemented by slo18.

Images (0)
Mutant
Wild-type
Stocks (2)
Notes on Origin
Discoverer
Comments
Comments

The physiological properties and role in membrane excitability of ICF, the voltage-activated fast K+ current (IA) and the voltage-activated delayed K+ current (IK) have been investigated using Sh14 and slo1 mutant larval muscle fibres and quinidine (which blocks IK). Current-clamp recordings from wild-type, Sh14, slo1 and Sh14 slo1 double mutant larval muscle fibres suggest that ICF plays a stronger role than IA in repolarisation of the larval muscle membrane.

Eliminate the ICF, fast Ca2+ activated K+ current.

External Crossreferences and Linkouts ( 0 )
Synonyms and Secondary IDs (4)
References (22)