FlyBase Allele Report: Dmel\EndoA[EP927]

General Information

Symbol

Dmel\EndoA^EP927

Species

D. melanogaster

Name

FlyBase ID

FBal0219576

Feature type

allele

Associated gene

Dmel\EndoA

Associated Insertion(s)

P{EP}EndoA^EP927

Carried in Construct

Also Known As

endo¹, EP(3)0927

Key Links

Genomic Maps

JBrowse

Allele class

loss of function allele

Mutagen

P-element activity

Nature of the Allele

Allele class

loss of function allele

(Rikhy et al., 2002)

Mutagen

P-element activity

(Bidet et al., 2003, Verstreken et al., 2002, Gene Disruption Project members, 2001-)

Progenitor genotype

Associated Insertion(s)

P{EP}EndoA^EP927

Cytology

Description

P{EP} insertion 8bp upstream of the endoA translation initiation codon. The P{EP} element is oriented such that expression from the element should result in overexpression of endoA.

(Bidet et al., 2003)

The P{EP} insertion is within the 5' UTR and in the correct orientation for endoA expression.

(Verstreken et al., 2002)

Allele components

Component

Use(s)

Inserted element

P{EP}

misexpression element

Regulatory region(s)

UAS

binary expression system - regulatory region

Mutations Mapped to the Genome

Curation Data

Type

Location

Additional Notes

References

transposable_element_insertion_site

3R:18,906,833..18,906,833 [+]

(Dickman, 2006, Pawlu et al., 2004, Bidet et al., 2003, Fabian-Fine et al., 2003, Verstreken et al., 2002, Gene Disruption Project members, 2001-)

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

(Verstreken et al., 2002)

abnormal neuroanatomy, with Scer\GAL4^arm.PS

(Rikhy et al., 2002)

abnormal neuroanatomy, with Scer\GAL4^rn-GAL4-14

(Dickman et al., 2006)

abnormal neuroanatomy (with EndoA^Δ4)

(Dickman et al., 2006)

abnormal neuroanatomy (with EndoA^Δ4), with Scer\GAL4^rn-GAL4-14

(Dickman et al., 2006)

abnormal neuroanatomy | recessive | somatic clone

(Kjaerulff et al., 2001)

abnormal neuroanatomy | somatic clone

(Fabian-Fine et al., 2003)

abnormal neurophysiology

(Pawlu et al., 2004, Verstreken et al., 2003, Verstreken et al., 2002)

abnormal neurophysiology, with Scer\GAL4^arm.PS

(Rikhy et al., 2002)

abnormal neurophysiology | recessive

(Kjaerulff et al., 2001)

abnormal neurophysiology | recessive | somatic clone

(Kjaerulff et al., 2001)

abnormal neurophysiology | somatic clone

(Fabian-Fine et al., 2003, Rikhy et al., 2002)

abnormal phototaxis | somatic clone

(Rikhy et al., 2002)

decreased rate of movement | larval stage | recessive

(Kjaerulff et al., 2001)

lethal | germline clone | larval stage | recessive

(Verstreken et al., 2002)

lethal | larval stage | recessive

(Verstreken et al., 2002)

lethal - all die before end of larval stage | recessive

(Kjaerulff et al., 2001)

lethal - all die before end of pupal stage (with EndoA^EP464)

(Verstreken et al., 2002)

lethal - all die before end of pupal stage (with EndoA^EP593)

(Verstreken et al., 2002)

some die during larval stage | recessive

(Kjaerulff et al., 2001)

some die during pupal stage (with EndoA^EP464)

(Verstreken et al., 2002)

some die during pupal stage (with EndoA^EP593)

(Verstreken et al., 2002)

viable, with Scer\GAL4^elav-C155

(Verstreken et al., 2002)

viable (with EndoA^EP3502)

(Verstreken et al., 2002)

Phenotype Manifest In

bouton

(Verstreken et al., 2002)

bouton | increased number, with Scer\GAL4^elav-C155

(Rikhy et al., 2002)

embryonic/larval neuromuscular junction, with Scer\GAL4^arm.PS

(Rikhy et al., 2002)

eye photoreceptor cell & synaptic vesicle | somatic clone

(Fabian-Fine et al., 2003)

eye photoreceptor cell | somatic clone

(Fabian-Fine et al., 2003)

NMJ bouton | increased number, with Scer\GAL4^rn-GAL4-14

(Dickman et al., 2006)

NMJ bouton | increased number (with EndoA^Δ4)

(Dickman et al., 2006)

NMJ bouton | increased number (with EndoA^Δ4), with Scer\GAL4^rn-GAL4-14

(Dickman et al., 2006)

photoreceptor cell & synaptic vesicle | somatic clone

(Kjaerulff et al., 2001)

presynaptic active zone, with Scer\GAL4^rn-GAL4-14

(Dickman et al., 2006)

presynaptic active zone (with EndoA^Δ4)

(Dickman et al., 2006)

presynaptic active zone (with EndoA^Δ4), with Scer\GAL4^rn-GAL4-14

(Dickman et al., 2006)

retina | somatic clone

(Rikhy et al., 2002)

synapse

(Verstreken et al., 2002)

synapse (with EndoA^Δ4)

(Verstreken et al., 2002)

synaptic vesicle

(Verstreken et al., 2002, Kjaerulff et al., 2001)

Detailed Description

Statement

Reference

Mutant neuromuscular junctions show reliable homeostatic compensation (increase in quantal content) after treatment with philanthotoxin-433 for 10 minutes.

(Dickman and Davis, 2009)

Primary cultured haemocytes from mutant third instar larvae internalise maleylated bovine serum albumin (mBSA) normally.

(Korolchuk et al., 2007)

endoA^EP927 larvae exhibit supernumerary boutons at neuromuscular junctions (a 10-fold increase, 31.1 compared to 2.48 satellite boutons/synapse). The boutons remain confined to the region of the muscle that normally receives the innervation, but this region is now crowded by the overgrowth of small boutons. No abnormalities are apparent at the end of embryogenesis.

endoA^Δ4/endoA^EP927 larvae exhibit supernumerary boutons at neuromuscular junctions (a 10-fold increase, 30.5 compared to 2.48 satellite boutons/synapse). The boutons remain confined to the region of the muscle that normally receives the innervation, but this region is now crowded by the overgrowth of small boutons. No abnormalities are apparent at the end of embryogenesis.

Overexpression of endoA^EP927, under the control of Scer\GAL4^elav-C155 in a endoA^EP927/endoA^Δ4 background restores wild-type structure to the synapse, with the same average number of boutons per synapse as in wild-type.

Overexpression of endoA^EP927, under the control of Scer\GAL4^rn-GAL4-14 in a endoA^EP927/endoA^Δ4 background fails to restore wild-type structure to the synapse.

(Dickman et al., 2006)

endoA^EP927 synaptic vesicles are able to load lipophilic dyes, but at a greatly reduced rate compared to wild-type vesicles, indicative of slowed endocytosis.

(Dickman et al., 2005)

The area ratio h of excitatory postsynaptic currents are reduced in mutants. The decay time is increased.

(Pawlu et al., 2004)

Eyes that have endoA^EP927 homozygous mutant photoreceptor cells, generated by mitotic recombination using the "EGUF/hid method", develop normally. Phototaxis is unaffected in these flies and they also show a normal light-evoked depolarization of the eye photoreceptor cell bodies. However, the on and off transients that occur in wild-type flies in response to a light flash are either severely reduced or absent in the mutants. When expression of endoA^EP927 is driven by Scer\GAL4^ey.PH, the on and off transient phenotype is rescued. The synaptic vesicles of endoA^EP927 photoreceptor terminals show an abnormal distribution and appearance compared to wild type. Although the overall packing density is not different, vesicles form more clusters and are packed more closely within the clusters. Additionally, the vesicles appear more electron dense on their surface than wild type. Counts of capitate projections, active zones and tetrad synapses are not different between endoA^EP927 and wild-type photoreceptor terminals.

(Fabian-Fine et al., 2003)

At Higher-frequency stimulation (10Hz) the amplitude of the excitatory junctional potentials (EJPs) declines rapidly (unlike controls) in mutants to about 20% of the original response and is then maintained for the remainder of the paradigm.

(Verstreken et al., 2003)

Expression of endoA^EP927, under the regulation of Scer\GAL4^ey.PH generates adult flies that are completely viable but that exhibit a sluggish phenotype. Expression of endoA^EP927, under the regulation of the ubiquitously expressed Scer\GAL4^arm.PS results in flies that progress well through development but are unable to eclose from the pupal case. Larval neuromuscular junction synapses of endoA^EP927 Scer\GAL4^arm.PS mutants are larger and exhibit a greater number of boutons (approximately a 75% increase on wild-type). The boutons appear morphologically smaller in size compared to wild-type. The increase in the number of boutons can be rescued through expression of Scer\GAL4^elav-C155;endoA^EP927/endoA^EP927, although some smaller boutons do still remain. The synapse architecture is unchanged when endoA^EP927 expression is driven by Scer\GAL4^Mhc.PW in a muscle-specific manner. Expression of endoA^EP927 under the regulation of Scer\GAL4^arm.PS does not affect third instar locomotion. However, intracellular recordings from the larval neuromuscular junction indicates an increase in the spontaneous miniature evoked junction potential (mEJP) size and frequency. The amplitude of the evoked response is also slightly higher than in wild-type. Despite this increase, the overall quantal content is unchanged in these mutants, along with no signs of synaptic depression consequent to a decrease in endophilin levels at the neuromuscular junction. Although the number of boutons is comparable to wild-type in Scer\GAL4^elav-C155; endoA^EP927/endoA^EP927 mutants, the synaptic physiology is rescued to a level only intermediate between the Scer\GAL4^arm.PS;endoA^EP927/endoA^EP927 mutant and the wild-type. Animals in which the eye is homozygous for endoA^EP927 (generated using the eyFLP method) have eyes which are morphologically indistinguishable to those of control lines. However, these flies show defects in electroretinogram (ERG) recordings; a constitutive loss of on- and off-transients is seen in many of the flies containing homozygous eyes (although on the first day after eclosion, the on-transient is present in all cases and an off-transient is present in some cases). The on-transient is intact in the mutant flies in the first few flashes of light given at 2Hz. However, after heightened photostimulation at 10Hz, the on-transient disappears in an activity-dependent manner in the mutant flies (the on-transient reappears after less than a 15 second rest period in the dark. Flies in which the eye is homozygous for endoA^EP927 are compromised in their ability to photo tax (move towards light).

(Rikhy et al., 2002)

Homozygous mutants are sluggish die during second and third instar larval stages. If the maternal contribution is also removed, the lethal stage remains the same. Neuromuscular junction synapse in homozygous endoA^EP927 and endoA^EP927/endoA^Δ4 animals are enlarged. The surface area of type I boutons are 196um² for homozygotes and 160um² for endoA^EP927/endoA^Δ4 animals, compared to 65um² in controls. endoA^EP927/endoA^EP464 and endoA^EP927/endoA^EP593 transheterozygotes die as pupae. endoA^EP3502/endoA^EP927 transheterozygotes are viable. The addition of Scer\GAL4^elav-C155 rescues endoA^EP927 to viability. The evoked excitatory junctional potentials (EJPs) in neuromuscular junctions (NMJs) of homozygous mutant larvae third instar are similar to controls for nerves stimulated at low frequency. However spontaneous miniature excitatory potentials (mEJPs) are less frequent in mutants than in controls. Large amplitude mEJPs occur more often in mutant animals than in controls; The average 95th (but not 5th or 50th) percentile of individiual mEJP amplitude distributions is increased in mutants. These results suggest exocytosis is not impaired, however tetanic stimulation experiments suggest that exocytosis is impaired in mutants - the EJP amplitude drops quickly to 20% of the pretetanic level after 100s and then maintains this level over the remaining 500s of the tetanus - This is different from controls which declines rapidly to about 60% of pretetanic levels and then slowly declines. The total number of released quanta is 2.5 fold lower in mutant synapses. The size of the functional vesicle pool in mutant boutons is about 13% of the control vesicle pool (when estimated by combining with shi¹ and measuring the total number of released quanta at the restrictive temperature.) Mutant boutons from early third instar larvae are enlarged and more compartmentalized than control boutons and strikingly, synaptic vesicles are severely reduced in number and largely confined to active zones and periphery of boutons, either in close association with the active zone, or in close proximity to the presynaptic membrane. The average vesicle density in endoA^EP927 mutants is reduced almost 8-fold compared to controls. In contrast the number of cisternae is similar to controls. The presynaptic membrane of mutants also have shallow pits more often than seen in controls. Dye uptake experiments demonstrate that Clathrin-mediated endocytosis from the presynaptic membrane is blocked in endoA^EP927 mutants. The smooth synaptic vesicles that associate with the active zone persist even after synaptic activity.

(Verstreken et al., 2002)

Larvae are sluggish. Synaptic vesicle endocytosis is defective. Clones in the eye show normal morphology but postsynaptic (wild type) lamina neurons are not activated. Photoreceptor terminal show reduction in number of synaptic vesicles.

(Kjaerulff et al., 2001)

External Data

Linkouts

Interactions

Show genetic interaction network for Enhancers & Suppressors

Phenotypic Class

Other

Statement

Reference

EndoA^EP927, Manf^35E has lethal | larval stage phenotype

(Magdalena, 2009)

EndoA^EP927, Synj¹ has abnormal neuroanatomy phenotype

(Verstreken et al., 2003)

EndoA^EP927, Synj¹ has abnormal neurophysiology phenotype

(Verstreken et al., 2003)

Phenotype Manifest In

Suppressor of

Statement

Reference

EndoA^EP927 is a suppressor of eye photoreceptor cell & synaptic vesicle phenotype of shi¹

(Fabian-Fine et al., 2003)

Other

Statement

Reference

EndoA^EP927, shi¹ has eye photoreceptor cell & clathrin-coated vesicle phenotype

(Fabian-Fine et al., 2003)

EndoA^EP927, shi¹ has eye photoreceptor cell & epithelial glial cell phenotype

(Fabian-Fine et al., 2003)

EndoA^EP927, shi¹ has eye photoreceptor cell & t-bar phenotype

(Fabian-Fine et al., 2003)

Additional Comments

Genetic Interactions

Statement

Reference

Flies with endoA^EP927;shi¹ eyes suffer a depletion of functional synaptic vesicles when raised to 29^oC for 15 minutes to the same extent as flies with single shi¹ mutant eyes. After 30 minutes of recovery time at 18^oC following the 15 minutes at 29^oC, endoA^EP927;shi¹ photoreceptor terminals show an increased number of capitate projections, which are invaginations of epithelial glia, compared to shi¹ single mutants. Additionally, membrane sheets emerging from near the pedestal of the T-bar ribbon of photoreceptor terminals persist for longer during the recovery time in endoA^EP927;shi¹ double mutants than shi¹ single mutants. There is less synaptic vesicle depletion in endoA^EP927;shi¹ mutant terminals following exposure to 29^oC than in shi¹ terminals. These vesicles appear clustered and electron dense in the double mutants, similar to their appearance in endoA^EP927 single mutants. In endoA^EP927;shi¹ mutants, free vesicles persist during exposure to 29^oC, while in shi¹ mutants, vesicles do not remain coated at this temperature.

(Fabian-Fine et al., 2003)

endoA¹, synj¹ transheterozygotes develop normally. However the on/off transients in electroretinogram (ERG) recordings are absent in these mutants. Mutants also phototaxis normally. Photoreceptors form normal cartridges in the lamina; however rows of densely coated vesicles accumulate in mutant photoreceptor terminals. At Higher-frequency stimulation (10Hz) the amplitude of the excitatory junctional potentials (EJPs) declines rapidly (unlike controls) in mutants to about 20% of the original response and is then maintained for the remainder of the paradigm.

(Verstreken et al., 2003)

Xenogenetic Interactions

Statement

Reference

Complementation and Rescue Data

Rescued by

EndoA^EP927 is rescued by EndoA^Tag:CALI(4C)

(Kasprowicz et al., 2014)

EndoA^EP927 is rescued by EndoA^{+tCH322-19L12}

(Venken et al., 2009)

Comments

EndoA^T:Zzzz\4C rescues the lethality of EndoA^EP927.

(Kasprowicz et al., 2014)

Images (0)

Mutant

Wild-type

Stocks (1)

Bloomington

24881

w^*; P{neoFRT}82B P{EP}EndoA^EP927/TM6B, Tb¹

Notes on Origin

Discoverer

Comments

Excision of the P{EP} element reverts the mutant phenotype. Phenotypic analysis provides an allelic series: endoA^Δ4 = endoA^EP927 > endoA^EP927 >= endoA^EP593 > endoA^Δ4.

(Verstreken et al., 2002)

P{EP}endoA^EP927 contains a UAS sequence in the correct orientation to allow control of endoA expression by Scer\GAL4.

(Dickman, 2006)

External Crossreferences and Linkouts ( 0 )

Synonyms and Secondary IDs (4)

Reported As

Symbol Synonym

EndoA^EP927

endo¹

(Kasprowicz et al., 2014, Venken et al., 2009, Dickman, 2006, Dickman et al., 2006, Dickman et al., 2005, Pawlu et al., 2004, Fabian-Fine et al., 2003, Verstreken et al., 2002)

endoA¹

(Korolchuk et al., 2007)

endoA^EP927

(Chance and Bashaw, 2015, Magdalena, 2009)

Name Synonyms

Secondary FlyBase IDs

FBal0130375
FBal0130379

References (18)

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