FlyBase Allele Report: Dmel\Syt4[BA1]

General Information

Symbol

Dmel\Syt4^BA1

Species

D. melanogaster

Name

FlyBase ID

FBal0191284

Feature type

allele

Associated gene

Dmel\Syt4

Associated Insertion(s)

Carried in Construct

Key Links

Allele class

amorphic allele - molecular evidence

Mutagen

P-element activity

Nature of the Allele

Allele class

amorphic allele - molecular evidence

(Saraswati et al., 2007)

Mutagen

P-element activity

(Barber et al., 2009, Adolfsen et al., 2004)

Progenitor genotype

P{EPgy2}EY09259

(Barber et al., 2009, Adolfsen et al., 2004)

Cytology

Description

Imprecise excision of P{EPgy2}EY09259, found 100bp 5' of the Syt4 transcription start site.

(Barber et al., 2009)

SytIV^BA1 is an intragenic deletion that removes SytIV immunoreactivity.

(Adolfsen et al., 2004)

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 neuroanatomy

(Yoshihara et al., 2005)

abnormal neuroanatomy | recessive | third instar larval stage

(Harris et al., 2016)

abnormal neuroanatomy | third instar larval stage (with Df(3R)rn¹⁶)

(Korkut et al., 2013)

abnormal neurophysiology

(Barber et al., 2009)

abnormal neurophysiology | third instar larval stage

(Cho et al., 2015)

abnormal neurophysiology | third instar larval stage (with Df(3R)rn¹⁶)

(Korkut et al., 2013)

Phenotype Manifest In

Detailed Description

Statement

Reference

Syt4^BA1/Syt4^BA1 third instar larvae have significantly fewer synaptic boutons and a significantly reduced ability to grow new "ghost" boutons under high K[+] stimulation at the neuromuscular junction compared to controls. Syt4^BA1/+ heterozygotes have similar numbers of boutons as controls.

(Harris et al., 2016)

Syt4^BA1 mutant third instar larvae do not display any synaptic overgrowth (assessed by the number of boutons) at neuromuscular junctions compared to controls. Syt4^BA1 mutants do not show the activity-dependent enhancement of spontaneous release that is normally observed in wild-type and in contrast to controls their frequency of minis prior and post high-frequency stimulation remains the same.

(Cho et al., 2015)

Syt4^BA1 mutants reduce synaptic growth at the neuromuscular junction with a 24% decrease in varicosity number compared to controls. Active zone number appears to parallel bouton number.

Syt4^BA1/Df(3R)rn¹⁶ mutants reduce synaptic growth at the neuromuscular junction with a 28% decrease in varicosity number compared to controls. Active zone number appears to parallel bouton number.

Homozygous Syt4^BA1 mutants exhibit reduced spontaneous neurotransmitter release in the absence of nerve stimulation (at 0.5mM Ca[2+] concentration). These changes in evoked responses are not observed in 2.0mM extracellular Ca[2+] concentration, suggesting that alterations in release probability or vesicle pool size may compensate for the altered number of release sites. The fast component of synaptic depression release during initial stimulation is unchanged. However, a lower depletion of synaptic vesicles and a higher baseline-evoked response during steady-state stimulation is observed in Syt4^BA1 mutants.

Syt4^BA1 mutants fail to show increased spontaneous release after stimulation.

Althoygh control larvae show a 33% increase in bouton number when reared at 31[o]c compared with 25[o]C, Syt4^BA1 mutants display no statistically significant increase in bouton number at 31[o]C.

(Barber et al., 2009)

There are no statistical differences in evoked excitatory junctional potential amplitudes between Syt4^BA1 animals and controls, even at low 0.1 mM extracellular Ca[2+] concentrations. Also, the amount of facilitation at all interpulse intervals tested was statistically the same as controls, indicating paired-pulse facilitation is unaffected.

(Saraswati et al., 2007)

High-frequency-stimulation-induced miniature release (HFMR) is eliminated in the neuromuscular junctions of SytIV^BA1 animals, in contrast to controls. The presynaptic morphology of motor terminals is abnormal at the mutant neuromuscular junction; the motor terminals fail to constrict into normal synaptic varicosities and maintain a flat, less varicose appearance.

(Yoshihara et al., 2005)

External Data

Linkouts

Interactions

Show genetic interaction network for Enhancers & Suppressors

Phenotypic Class

Enhanced by

Statement

Reference

Syt4^BA1 has abnormal neuroanatomy | third instar larval stage | recessive phenotype, enhanceable by Syx4[+]/Syx4⁷³

(Harris et al., 2016)

Suppressed by

Statement

Reference

Syt4^BA1 has abnormal neuroanatomy phenotype, suppressible by Mmus\Prkaca^mC.UAS/Scer\GAL4^Toll-6-D42

(Yoshihara et al., 2005)

NOT Enhancer of

Statement

Reference

Syt4[+]/Syt4^BA1 is a non-enhancer of abnormal neuroanatomy | third instar larval stage | recessive phenotype of Syx4⁷³

(Harris et al., 2016)

Syt4^BA1 is a non-enhancer of abnormal neurophysiology phenotype of Syt1^AD4/Syt1^N13

(Saraswati et al., 2007)

Suppressor of

Statement

Reference

Syt4^BA1 is a suppressor of abnormal neuroanatomy | temperature conditional phenotype of para^ts1

(Barber et al., 2009)

Syt4^BA1 is a suppressor of abnormal neuroanatomy | temperature conditional phenotype of sei¹

(Barber et al., 2009)

NOT Suppressor of

Statement

Reference

Syt4^BA1/Syt4^BA1 is a non-suppressor of abnormal neurophysiology | third instar larval stage phenotype of cpx^SH1

(Cho et al., 2015)

Syt4^BA1/Syt4^BA1 is a non-suppressor of abnormal neurophysiology | third instar larval stage phenotype of Syx1A^3-69

(Cho et al., 2015)

Other

Statement

Reference

Df(3R)Nlg1^ex3.1/+, Syt4^BA1 has abnormal neuroanatomy | third instar larval stage phenotype

(Harris et al., 2016)

Syt4[+]/Syt4^BA1, Syx4⁷³ has abnormal neuroanatomy phenotype

(Harris et al., 2016)

Syt4^BA1, Syx4⁷³ has lethal - all die during second instar larval stage phenotype

(Harris et al., 2016)

Phenotype Manifest In

Enhanced by

Statement

Reference

Syt4^BA1 has NMJ bouton | third instar larval stage phenotype, enhanceable by Syx4[+]/Syx4⁷³

(Harris et al., 2016)

Suppressed by

Statement

Reference

Syt4^BA1 has neuromuscular junction | temperature conditional phenotype, suppressible by para^ts1

(Barber et al., 2009)

Syt4^BA1 has NMJ bouton | temperature conditional phenotype, suppressible by para^ts1

(Barber et al., 2009)

Syt4^BA1 has motor neuron phenotype, suppressible by Mmus\Prkaca^mC.UAS/Scer\GAL4^Toll-6-D42

(Yoshihara et al., 2005)

NOT Enhancer of

Statement

Reference

Syt4[+]/Syt4^BA1 is a non-enhancer of NMJ bouton | third instar larval stage phenotype of Syx4⁷³

(Harris et al., 2016)

Suppressor of

Statement

Reference

Syt4^BA1/Syt4^BA1 is a suppressor of neuromuscular junction | third instar larval stage phenotype of cpx^SH1

(Cho et al., 2015)

Syt4^BA1/Syt4^BA1 is a suppressor of NMJ bouton | third instar larval stage phenotype of cpx^SH1

(Cho et al., 2015)

Syt4^BA1/Syt4^BA1 is a suppressor of neuromuscular junction | third instar larval stage phenotype of Syx1A^3-69

(Cho et al., 2015)

Syt4^BA1/Syt4^BA1 is a suppressor of NMJ bouton | third instar larval stage phenotype of Syx1A^3-69

(Cho et al., 2015)

Syt4^BA1 is a suppressor of neuromuscular junction | temperature conditional phenotype of para^ts1

(Barber et al., 2009)

Syt4^BA1 is a suppressor of neuromuscular junction | temperature conditional phenotype of sei¹

(Barber et al., 2009)

Syt4^BA1 is a suppressor of NMJ bouton | temperature conditional phenotype of sei¹

(Barber et al., 2009)

Other

Statement

Reference

Df(3R)Nlg1^ex3.1/+, Syt4^BA1 has NMJ bouton | third instar larval stage phenotype

(Harris et al., 2016)

Syt4[+]/Syt4^BA1, Syx4⁷³ has NMJ bouton | third instar larval stage phenotype

(Harris et al., 2016)

Additional Comments

Genetic Interactions

Statement

Reference

Syx4⁷³/+ or Syt4^BA1/+ third instar larvae do not show significant differences in bouton number at the neuromuscular junction compared to controls, but Syx4⁷³/+;Syt4^BA1//+ double heterozygotes have significantly fewer boutons compared to controls or either single heterozygote. Syx4⁷³/Y;Syt4^BA1/Syt4^BA1 mutants die during the second instar larval stage. Syx4⁷³/+ significantly enhances the reduction in bouton number at the NMJ of Syt4^BA1/Syt4^BA1 third instar larvae. Syt4^BA1/+ does not significantly enhance the reduction in bouton number at the NMJ of Syx4⁷³/Y hemizygous third instar larvae.

Syt4^BA1/+;Df(3R)Nlg1^ex3.1/+ larvae have a significantly reduced ability to grow new "ghost" boutons under high K[+] stimulation at the neuromuscular junction compared to controls and single heterozygotes (though double heterozygotes do not show significant changes in the number of boutons under normal conditions compared to controls).

(Harris et al., 2016)

The synaptic overgrowth (increased number of boutons) at neuromuscular junctions observed in third instar larvae mutant for either cpx^SH1 or Syx1A^3-69 can be suppressed by homozygosity of Syt4^BA1 (which on its own does not lead to any elevation in synaptic growth) but this fails to suppress the increased frequency of mini excitatory junction potentials.

(Cho et al., 2015)

sei¹ ; Syt4^BA1 double mutants exhibit no significant change in bouton number between 25[o]c and 31[o]C.

Synaptic outgrowth induced by expression of Syt4^wt.Scer\UAS under the control of Scer\GAL4^Mhc.PW is dramatically reduced in a para^ts1 background when animals are reared at 31[o]C compared with 25[o]C.

(Barber et al., 2009)

Like Syt1^AD4/Syt1^N13 mutants alone, Syt1^AD4/Syt1^N13, Syt4^BA1 double mutants display robust asynchronous release. Paired-pulse facilitation remains intact in the double mutants, with enhanced facilitation as observed in Syt1^AD4/Syt1^N13 mutants alone. Also similar to Syt1^AD4/Syt1^N13 mutants alone, the release observed during paired-pulse stimulation in the double mutants remains asynchronous compared to wild type controls.

(Saraswati et al., 2007)

Xenogenetic Interactions

Statement

Reference

Expression of Mmus\Pkaca^mC.Scer\UAS under the control of Scer\GAL4^D42 restores the normal constricted varicosities at the motor terminals of the SytIV^BA1 neuromuscular junction.

(Yoshihara et al., 2005)

Complementation and Rescue Data

Rescued by

Syt4^BA1 is rescued by Syt4^{UAS.pHluorinE}/Scer\GAL4^how-24B

(Harris et al., 2016)

Df(3R)rn¹⁶/Syt4^BA1 is rescued by Scer\GAL4^elav-C155/Syt4^UAS.Tag:MYC

(Korkut et al., 2013)

Df(3R)rn¹⁶/Syt4^BA1 is rescued by Scer\GAL4^elav-C155/Syt4^UAS.cLa

(Korkut et al., 2013)

Df(3R)rn¹⁶/Syt4^BA1 is rescued by Scer\GAL4^Mhc.PW/Syt4^UAS.cLa

(Korkut et al., 2013)

Df(3R)rn¹⁶/Syt4^BA1 is rescued by Scer\GAL4^Mhc.PW/Syt4^wt.UAS

(Barber et al., 2009)

Not rescued by

Df(3R)rn¹⁶/Syt4^BA1 is not rescued by Syt4^S284A.UAS/Scer\GAL4^Mhc.PW

(Barber et al., 2009)

Df(3R)rn¹⁶/Syt4^BA1 is not rescued by Scer\GAL4^Mhc.PW/Syt4^C2A.C2B.UAS

(Yoshihara et al., 2005)

Comments

Expression of Syt4^{UAS.pHluorinE} driven by Scer\GAL4^how-24B rescues bouton number at the neuromuscular junction of Syt4^BA1/Syt4^BA1 third instar larvae; Syt4^{UAS.pHluorinE} driven by Scer\GAL4^how-24B also rescues ability of mutants to grow new "ghost" boutons under high K[+] stimulation.

(Harris et al., 2016)

Expression of Syt4^wt.Scer\UAS post-synaptically under the control of Scer\GAL4^Mhc.PW rescues the Syt4^BA1/Df(3R)rn¹⁶ synaptic growth defect.

(Barber et al., 2009)

Images (0)

Mutant

Wild-type

Stocks (0)

Notes on Origin

Discoverer

External Crossreferences and Linkouts ( 0 )

Synonyms and Secondary IDs (4)

Reported As

Symbol Synonym

Syt4^BA1

(Ho and Treisman, 2020, Harris et al., 2016, Barber et al., 2009)

SytIV^BA1

syt 4^BA1

(Cho et al., 2015)

syt4^BA1

(Huang et al., 2019, Korkut et al., 2013, Saraswati et al., 2007, Yoshihara et al., 2005)

Name Synonyms

Secondary FlyBase IDs

References (9)

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