Allele Dmel\sei¹

General Information
Symbol	Dmel\sei¹	Species	D. melanogaster
Name		FlyBase ID	FBal0015409
Feature type	allele	Associated gene	Dmel\sei
Also Known As	sei^ts1

Map ( GBrowse )
Allele class
Mutagen	ethyl methanesulfonate
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.
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FB2013_03
FB2013_02
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Nature of the Allele
Allele class
Mutagen	ethyl methanesulfonate (Titus et al., 1997, Wang et al., 1997)
Mutations Mapped to the Genome

Type Location Additional Notes References point mutation 2R:19,937,797..19,937,797 na_change=A19937797T pr_change=K282\|sei-PA,K282\|sei-PB reported_pr_change=K282@ (Titus et al., 1997, Wang et al., 1997)
Associated Sequence Data
DDBJ / EMBL / GenBank	DNA sequence Protein sequence Name

UniProtKB/Swiss-Prot
UniProtKB/TrEMBL

Progenitor genotype
Nature of the lesion	Statement Reference Amino acid replacement: K282. K282 lies before the first membrane-spanning segment. (Titus et al., 1997) Amino acid replacement: K282@. Resulting protein completely lacks the hydrophobic core that forms the transmembrane channel. (Wang et al., 1997)
Cytology
Phenotypic Data
Phenotypic Class
	behavior defective \| heat sensitive (Hoeffer et al., 2003) neuroanatomy defective (Lee and Wu, 2010) neuroanatomy defective (with sei²) (Lee and Wu, 2010) neuroanatomy defective \| heat sensitive (Jarecki and Keshishian, 1995, Lee and Wu, 2010) neuroanatomy defective \| temperature conditional (Barber et al., 2009) neurophysiology defective \| heat sensitive (Fergestad et al., 2010) paralytic \| heat sensitive (Jackson et al., 1985, Pavlidis and Tanouye, 1995, Wang et al., 1995, Titus et al., 1997, Fergestad et al., 2006, Wang et al., 1997, Fergestad et al., 2010)
Phenotype Manifest In
	adult central nervous system (Fergestad et al., 2006) dorsal medial muscle (Fergestad et al., 2010) neuromuscular junction (Lee and Wu, 2010) neuromuscular junction (with sei²) (Lee and Wu, 2010) neuromuscular junction & synapse (Jarecki and Keshishian, 1995) neuromuscular junction \| heat sensitive (Lee and Wu, 2010) neuromuscular junction \| temperature conditional (Barber et al., 2009) NMJ bouton \| ectopic (with sei²) (Lee and Wu, 2010) NMJ bouton \| supernumerary (Lee and Wu, 2010) NMJ bouton \| supernumerary (with sei²) (Lee and Wu, 2010) NMJ bouton \| supernumerary \| heat sensitive (Lee and Wu, 2010) NMJ bouton \| temperature conditional (Barber et al., 2009) synapse \| ectopic \| heat sensitive (Jarecki and Keshishian, 1995)
Detailed Description
	Statement Reference Intracellular recordings from mutant dorsal longitudinal muscles show bursts of spontaneous activity at 37[o]C. (Fergestad et al., 2010) sei[1]/sei[2] 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 M satellites are more abundant than type B satellites in these mutants. There is also an overall increase in synaptic bouton number and terminal branching in these mutants. sei[1] mutants display significantly enhanced branching patterns along with a robust increase in mature bouton numbers, indicating that sei mutants do not fully prevent type M satellites from entering the successive growth steps. Exposure to high temperatures (29[o]C) for 2 hours during development fails to induce significant morphological changes in synaptic growth in sei[1] 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. Chronic high temperature treated (>5 hours) sei[1] mutants exhibit an unusual population of terminal branches consisting of thin strings of type M (and occasionally type B) satellites that are absent in controls. These unusual terminal branches contribute to the increased branching complexity in sei[1] mutants. These mutants also exhibit a decrease in primary bouton number. (Lee and Wu, 2010) sei[1] mutants display a 60% increase in bouton number at 31[o]C compared with 25[o]C. (Barber et al., 2009) sei¹ flies do not show a significantly shortened lifespan. At day 37, these flies exhibit sporadic vacuoles throughout the central nervous system. Exposing these mutants to 40^oC for 3 minutes results in seizures that last for up to a minute followed by paralysis. The severity of the phenotype progresses with age and daily exposure to the restrictive temperature. (Fergestad et al., 2006) sei¹ mutants show behavioral convulsions after brief exposure to elevated temperature. (Hoeffer et al., 2003) The courtship song parameters interpulse interval, cycles per pulse, interpulse frequency and amplitude of sound are normal in homozygous males at 25^oC. (Peixoto and Hall, 1998) Substantial enhancement of spontaneous neural activity. (Titus et al., 1997) Heat induced expression of sei^hs.PW in adults is sufficient to restore normal locomotor function. (Wang et al., 1997) Homozygous larvae raised at the restrictive temperature (37^oC for 6 hours/day from late embryogenesis through to third larval instar) show an increased frequency of ectopic neuromuscular synapses. Embryos raised at 18^oC or 34^oC show an increased frequency of immature filopodial contacts on muscle fibres 6 and 7 ("collateral sprouts") compared to wild-type embryos raised at the same temperature. (Jarecki and Keshishian, 1995) The delivery of an electrical buzz (50-400 msec) to the brain has no significant effect on sei¹ mutant flies. (Pavlidis and Tanouye, 1995) Spontaneous dorsal longitudinal muscle responses increase in frequency as the temperature is increased. (Elkins and Ganetzky, 1990) At temperatures >40^oC, sei² causes spontaneous activity in recordings from dorsal longitudinal flight muscles, to appear coincidentally with the heat-induced paralysis. (Kasbekar et al., 1987) sei² is semidominant in this respect and behavior of hyperploid adults exhibits dose dependence: sei²/sei²/+ flies become paralyzed, at 40^oC, slightly less rapidly than homozygous mutants; sei²/+/+ paralyzed more slowly than sei²/+ but faster than wild-type. (Jackson et al., 1985) Recordings of action potentials in the adult giant-fiber pathway reveal no decrement in sei² at 40^oC. (Nelson and Baird, 1985) temperature-sensitive
External Data
Linkouts
Interactions
	Show the genetic interaction network for Enhancers & Suppressors
Phenotypic Class
Enhanced by
Statement Reference sei¹ has neuroanatomy defective phenotype, enhanceable by sei¹ (Lee and Wu, 2010, Lee and Wu, 2010)
Suppressed by
Statement Reference sei¹ has neuroanatomy defective \| temperature conditional phenotype, suppressible by Syt4^BA1 (Barber et al., 2009)
Enhancer of
Statement Reference sei¹ is an enhancer of neuroanatomy defective phenotype of sei¹ (Lee and Wu, 2010, Lee and Wu, 2010)
NOT Enhancer of
Statement Reference sei¹/sei[+] is a non-enhancer of short lived \| dominant phenotype of Atpα^DTS1 (Fergestad et al., 2006)
Suppressor of
Statement Reference sei¹ is a suppressor of neuroanatomy defective phenotype of slo¹ (Lee and Wu, 2010)
Phenotype Manifest In
Enhanced by
Statement Reference sei¹ has neuromuscular junction phenotype, enhanceable by sei¹ (Lee and Wu, 2010, Lee and Wu, 2010) sei¹ has NMJ bouton \| supernumerary phenotype, enhanceable by sei¹ (Lee and Wu, 2010, Lee and Wu, 2010) sei¹ has phenotype, enhanceable by e(sei)¹
Suppressed by
Statement Reference sei¹ has neuromuscular junction \| temperature conditional phenotype, suppressible by Syt4^BA1 (Barber et al., 2009) sei¹ has NMJ bouton \| temperature conditional phenotype, suppressible by Syt4^BA1 (Barber et al., 2009)
Enhancer of
Statement Reference sei¹ is an enhancer of neuromuscular junction phenotype of sei¹ (Lee and Wu, 2010, Lee and Wu, 2010) sei¹ is an enhancer of NMJ bouton \| supernumerary phenotype of sei¹ (Lee and Wu, 2010, Lee and Wu, 2010)
Suppressor of
Statement Reference sei¹ is a suppressor of neuromuscular junction phenotype of slo¹ (Lee and Wu, 2010) sei¹ is a suppressor of NMJ bouton \| supernumerary phenotype of slo¹ (Lee and Wu, 2010)
Additional Comments
Genetic Interactions
Statement Reference dao[b4] sei[1]/dao[g1] sei[1] double mutants show the same time to paralysis on shifting to the restrictive temperature as either single mutant. (Fergestad et al., 2010) When compared with single mutants, the combined mutational effects of sei[1]/slo[1] are not simply additive, with a further enhancement of some slo, but not sei phenotypes. Satellite abundance is less extreme in sei[1]/slo[1] double mutants compared to sei[1] 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. (Lee and Wu, 2010) sei[1] ; Syt4[BA1] double mutants exhibit no significant change in bouton number between 25[o]c and 31[o]C. (Barber et al., 2009) sei¹/+; Atpα^DTS1/+ double mutants have a similar lifespan to Atpα^DTS1/+ single mutants. (Fergestad et al., 2006)
Xenogenetic Interactions
Statement Reference
Complementation & Rescue Data
Rescued by	sei¹ is rescued by sei^hs.PW (Wang et al., 1997)
Comments
Stocks ( 0 )

Notes on Origin
Discoverer

Comments
	Reduced level of saxitoxin binding in head membrane extracts and a decreased sodium current density in cultured embryonic neurons. (Wang et al., 1995)
External Crossreferences & Linkouts
Other Crossreferences

Linkouts

Synonyms & Secondary IDs ( 4 )
Reported As
Symbol Synonym	sei¹ sei^ts1 (Fergestad et al., 2006, Ghezzi et al., 2004, Peixoto and Hall, 1998, Wang et al., 1997, Titus et al., 1997, Pavlidis and Tanouye, 1995, Wang et al., 1995, Elkins and Ganetzky, 1990, Guan et al., 2011, Barber et al., 2009, Fergestad et al., 2010, Lee and Wu, 2010) sei^TS1 (Guan et al., 2011) sei^ts (Hoeffer et al., 2003)
Name Synonym
Secondary FlyBase IDs

References ( 19 )
Research paper	Guan et al., 2011, Learn. Mem. 18(4): 191--206 Altered gene regulation and synaptic morphology in Drosophila learning and memory mutants. [FBrf0213277] Fergestad et al., 2010, Proc. Natl. Acad. Sci. U.S.A. 107(12): 5617--5621 A Drosophila behavioral mutant, down and out (dao), is defective in an essential regulator of Erg potassium channels. [FBrf0210402] Lee and Wu, 2010, J. Neurosci. 30(47): 15821--15833 Orchestration of stepwise synaptic growth by k+ and Ca2+ channels in Drosophila. [FBrf0212405] Barber et al., 2009, J. Cell Biol. 187(2): 295--310 Postsynaptic regulation of synaptic plasticity by synaptotagmin 4 requires both C2 domains. [FBrf0208997] Fergestad et al., 2006, Genetics 172(2): 1031--1042 Neuropathology in Drosophila membrane excitability mutants. [FBrf0190718] Ghezzi et al., 2004, Proc. Natl. Acad. Sci. U.S.A. 101(49): 17276--17281 slo K+ channel gene regulation mediates rapid drug tolerance. [FBrf0180655] Hoeffer et al., 2003, J. Neurosci. 23(15): 6362--6372 Acute induction of conserved synaptic signaling pathways in Drosophila melanogaster. [FBrf0160607] Peixoto and Hall, 1998, Genetics 148(2): 827--838 Analysis of temperature-sensitive mutants reveals new genes involved in the courtship song of Drosophila. [FBrf0101981] Titus et al., 1997, J. Neurosci. 17(3): 875--881 The Drosophila erg K⁺ channel polypeptide is encoded by the seizure locus. [FBrf0092706] Wang et al., 1997, J. Neurosci. 17(3): 882--890 The seizure locus encodes the Drosophila homolog of the HERG potassium channel. [FBrf0092719] Jarecki and Keshishian, 1995, J. Neurosci. 15(12): 8177--8190 Role of neural activity during synaptogenesis in Drosophila. [FBrf0085285] Pavlidis and Tanouye, 1995, J. Neurosci. 15(8): 5810--5819 Seizures and failures in the giant fiber pathway of Drosophila bang-sensitive paralytic mutants. [FBrf0083354] Amichot et al., 1993, Insect Biochem. Mol. Biol. 23(3): 381--390 Transcription analysis of the para gene by in situ hybridisation and immunological characterization of ite expression product in wild-type and mutant strains of Drosophila. [FBrf0058672] Elkins and Ganetzky, 1990, J. Neurogenet. 6: 207--219 Conduction in the giant nerve fiber pathway in temperature-sensitive paralytic mutants of Drosophila. [FBrf0052392] O'Dowd and Aldrich, 1988, J. Neurosci. 8: 3633--3643 Voltage-clamp analysis of sodium channels in wild-type and mutant Drosophila neurons. [FBrf0048530] Kasbekar et al., 1987, Genetics 116: 423--431 Enhancer of seizure: a new genetic locus in Drosophila melanogaster defined by interactions with temperature-sensitive paralytic mutations. [FBrf0046376] Jackson et al., 1985, J. Neurosci. 5: 1144--1151 Genetic modifications of voltage-sensitive sodium channels in Drosophila: gene dosage studies of the seizure locus. [FBrf0043052]
Abstract	Wang et al., 1995, A. Dros. Res. Conf. 36: 108A Genetic analysis and molecular cloning of the seizure gene. [FBrf0079594] Nelson and Baird, 1985, Abstr. Soc. Neurosci. 11(1): 313 Action potentials persist at restrictive temperatures in temperature sensitive paralytic mutants of adult Drosophila. [FBrf0043557]

Allele Dmel\sei1

Allele Dmel\sei¹