Allele Dmel\Syt4^BA1

General Information
Symbol	Dmel\Syt4^BA1	Species	D. melanogaster
Name		FlyBase ID	FBal0191284
Feature type	allele	Associated gene	Dmel\Syt4

Allele class	amorphic allele - molecular evidence
Mutagen	P-element activity
Recent Updates
Description	What does this section display? This section contains items that were added to this record for each release. It currently only tracks new links between this FlyBase report and other FlyBase data classes (e.g. genes, references, stocks) or controlled vocabulary terms (e.g. GO, anatomy terms). What does this section not display? This section does not currently display links that were removed or gene model changes.
Update Feed	Click the icon below to subscribe to this FlyBase record and receive updates automatically through your feed reader.
FB2013_03
FB2013_02
All updates	Click here to see a list of all updates to this record from FB2010_08 and on.
Nature of the Allele
Allele class	amorphic allele - molecular evidence (Saraswati et al., 2007)
Mutagen	P-element activity (Adolfsen et al., 2004, Barber et al., 2009)
Mutations Mapped to the Genome

Type Location Additional Notes References
Associated Sequence Data
DDBJ / EMBL / GenBank	DNA sequence Protein sequence Name

UniProtKB/Swiss-Prot
UniProtKB/TrEMBL

Progenitor genotype	P{EPgy2}EY09259 (Barber et al., 2009, Adolfsen et al., 2004)
Nature of the lesion	Statement Reference 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)
Cytology
Phenotypic Data
Phenotypic Class
	neuroanatomy defective (Yoshihara et al., 2005) neurophysiology defective (Barber et al., 2009)
Phenotype Manifest In
	motor neuron (Yoshihara et al., 2005) neuromuscular junction (Yoshihara et al., 2005, Barber et al., 2009) neuromuscular junction (with Df(3R)rn¹⁶) (Barber et al., 2009) NMJ bouton (Barber et al., 2009) NMJ bouton (with Df(3R)rn¹⁶) (Barber et al., 2009)
Detailed Description
	Statement Reference 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)rn[16] 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 the genetic interaction network for Enhancers & Suppressors
Phenotypic Class
Suppressed by
Statement Reference Syt4^BA1 has neuroanatomy defective phenotype, suppressible by Mmus\Pkaca^mC.Scer\UAS/Scer\GAL4^D42 (Yoshihara et al., 2005)
NOT Enhancer of
Statement Reference Syt4^BA1 is a non-enhancer of neurophysiology defective phenotype of Syt1^AD4/Syt1^N13 (Saraswati et al., 2007)
Suppressor of
Statement Reference Syt4^BA1 is a suppressor of neuroanatomy defective \| temperature conditional phenotype of para^ts1 (Barber et al., 2009) Syt4^BA1 is a suppressor of neuroanatomy defective \| temperature conditional phenotype of sei¹ (Barber et al., 2009)
Phenotype Manifest In
Suppressed by
Statement Reference Syt4^BA1 has motor neuron phenotype, suppressible by Mmus\Pkaca^mC.Scer\UAS/Scer\GAL4^D42 (Yoshihara et al., 2005) 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)
Suppressor of
Statement Reference 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)
Additional Comments
Genetic Interactions
Statement Reference sei[1] ; 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 & Rescue Data
Rescued by	Df(3R)rn¹⁶/Syt4^BA1 is rescued by Scer\GAL4^Mhc.PW/Syt4^wt.Scer\UAS (Barber et al., 2009)
Not rescued by	Df(3R)rn¹⁶/Syt4^BA1 is not rescued by Scer\GAL4^Mhc.PW/Syt4^{C2A.C2B.Scer\UAS} (Yoshihara et al., 2005) Df(3R)rn¹⁶/Syt4^BA1 is not rescued by Syt4^{S284A.Scer\UAS}/Scer\GAL4^Mhc.PW (Barber et al., 2009)
Comments	Expression of Syt4[wt.Scer\UAS] post-synaptically under the control of Scer\GAL4[Mhc.PW] rescues the Syt4[BA1]/Df(3R)rn[16] synaptic growth defect. (Barber et al., 2009)
Stocks ( 0 )

Notes on Origin
Discoverer

External Crossreferences & Linkouts
Other Crossreferences

Linkouts

Synonyms & Secondary IDs ( 3 )
Reported As
Symbol Synonym	syt4^BA1 (Yoshihara et al., 2005, Saraswati et al., 2007) Syt4^BA1 (Barber et al., 2009) SytIV^BA1
Name Synonym
Secondary FlyBase IDs

References ( 4 )
Research paper	Barber et al., 2009, J. Cell Biol. 187(2): 295--310 Postsynaptic regulation of synaptic plasticity by synaptotagmin 4 requires both C2 domains. [FBrf0208997] Saraswati et al., 2007, Proc. Natl. Acad. Sci. U.S.A. 104(35): 14122--14127 Characterization of the role of the Synaptotagmin family as calcium sensors in facilitation and asynchronous neurotransmitter release. [FBrf0201175] Yoshihara et al., 2005, Science 310(5749): 858--863 Retrograde signalling by Syt 4 induces presynaptic release and synapse-specific growth. [FBrf0190621] Adolfsen et al., 2004, J. Cell Biol. 166(2): 249--260 Synaptotagmins are trafficked to distinct subcellular domains including the postsynaptic compartment. [FBrf0179104]

Allele Dmel\Syt4BA1

Allele Dmel\Syt4^BA1