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General Information
D. melanogaster
Saccharomyces cerevisiae UAS construct a of Pennetta
FlyBase ID
Feature type
Associated gene
Associated Insertion(s)
Carried in Construct
Also Known As
Allele class
Nature of the Allele
Allele class
Mutations Mapped to the Genome
Additional Notes
Associated Sequence Data
DNA sequence
Protein sequence
Progenitor genotype
Carried in construct
Nature of the lesion
UAS regulatory sequences drive expression of Vap33.
Allele components
Product class / Tool use(s)
Encoded product / tool
Expression Data
Reporter Expression
Additional Information
Marker for
Reflects expression of
Reporter construct used in assay
Human Disease Associations
Disease Ontology (DO) Annotations
Models Based on Experimental Evidence ( 1 )
Modifiers Based on Experimental Evidence ( 0 )
Comments on Models/Modifiers Based on Experimental Evidence ( 0 )
Phenotypic Data
Phenotypic Class
Phenotype Manifest In
Detailed Description
Presynaptic overexpression of Vap-33A, through expression of Vap-33AScer\UAS.cPa under the control of Scer\GAL4elav-C155 results in an increase in the number of synaptic boutons, with a concomitant decrease in their size. This phenotype is highly dependent on the level of Vap-33AScer\UAS.cPa expression. Many small boutons appear to bud off from a central bouton or from neuronal processes connecting two boutons. Indeed, presynaptic expression of Vap-33AV260I.Scer\UAS induces a 1-7-2.2-fold increase in the percentage of 'satellite' boutons compared to controls. Neuronal expression of Vap-33AScer\UAS.cPa under the control of Scer\GAL4elav-C155 affects the organization of microtubule architecture, with consequences on synaptic bouton formation and division. Post-synaptic expression of Vap-33AScer\UAS.cPa under the control of Scer\GAL4C57 induces aggregate formation and changes in nuclear shape, size and positioning. Muscle fiber nuclei are more closely associated in these mutants and exhibit a tendency to cluster. The nuclei are also deformed into an elongated structure and display a marked enlarged nuclear volume compared to controls. Large, malformed nuclei are observed in larval brains expressing Vap-33AScer\UAS.cPa under the control of Scer\GAL4elav-C155. These neurons exhibit prominent inclusions that appear to be very large and intensely immunoreactive to Vap-33A. Flies expressing Vap-33AScer\UAS.cPa under the control of Scer\GAL4elav-C155 are able to pupate. However, there is a strong reduction in the number of flies eclosed as viable adults in these mutants, with only 75% of pupae eclosing to viable adults. These flies display distinctive postural and locomotion defects as viable adults, such as droopy and held-up wings. These flies are severely uncoordinated and within a few days of eclosion find themselves stuck to their food and die. Targeted expression of Vap-33AScer\UAS.cPa in the adult eye, under the control of Scer\GAL4ey.PU, results in a range of structural abnormalities. Compared to controls, these eyes are reduced in size and show a marked roughness over the entire surface. There is a high degree of heterogeneity in the severity of the phenotype within the same line and indeed in the same fly. Overall, the eye size of Vap-33AScer\UAS.cPa-expressing mutants is 20-30% of the control size. Photoreceptor morphology is disrupted in these flies, with several vacuoles found.
In synaptic terminals overexpressing Vap-33-1Scer\UAS.cPa through the pan-neural driver Scer\GAL4elav-C155, the EJP amplitude is not significantly changed compared to controls. Conversely, there is a significant decrease in quantal size in these mutants. A significant increase in quantal content accompanies the increase in bouton number as the quantal content in Vap-33-1Scer\UAS.cPa overexpressing larvae is 54.13 compared with 36.66. Overexpression of Vap-33-1Scer\UAS.cPa in synaptic terminals under the control of Scer\GAL4elav-C155 does not affect the number of active zones per surface area. However, there are substantially more boutons which are significantly smaller in size when compared to wild-type boutons. In addition, these boutons appear to contain fewer vesicles. In every small bouton resulting from Vap-33-1Scer\UAS.cPa overexpression, more than 80% of the bouton cross-sectional area is devoid of synaptic vesicles, whereas in controls, numerous vesicles ae packed in each bouton, leaving only 40-50% of the bouton area devoid of synaptic vesicles.
Pre-synaptic expression of Vap-33-1Scer\UAS.cPa under the control of Scer\GAL4elav-C155 causes a significant increase in bouton number and reduced flight ability. 7% of the indirect flight muscles show severe defects and the myofibrils are more heterogeneous in size than in controls. Subtle but non-significant reductions in the excitatory junctional amplitude (EJP) and (miniEJP) are also seen.
Expression driven by Scer\GAL4elav-C155 or Scer\GAL4C164 in an otherwise wild type background causes a clear increase in bouton number and decrease in bouton size. Many synapses show extra branches, though axonal pathfinding and initial target recognition appear normal. In an otherwise null background the effect is intermediate, indicating a dose-dependence of effect on boutons of Vap-33-1 levels. Expression driven by Scer\GAL4C164 causes bouton microtubules to appear more dense and sturdy, with more evident loops, than in wild type. When expression is driven by Scer\GAL4elav-C155, localization of syt, Csp, Fas2 and dlg1 proteins is normal, indicating normal axonal transport.
External Data
Show genetic interaction network for Enhancers & Suppressors
Phenotypic Class
Phenotype Manifest In
Suppressed by
Suppressor of
Additional Comments
Genetic Interactions
lacek05305/lace2 transheterozygous and lace2 heterozygous adults that also express Vap33UAS.cPa under the control of Scer\GAL4Tab2-201Y do not show a mushroom body "lost lobe" phenotype.
Expression of Vap-33-1Scer\UAS.cPa in flies expressing OsbpScer\UAS.cMa under the control of Scer\GAL4Ccap.PP suppresses the unexpanded wing phenotype.
Ephunspecified suppresses the myofibrillar degeneration and variability in myofibril size seen in the indirect flight muscles when Vap-33-1Scer\UAS.cPa is expressed under the control of Scer\GAL4elav-C155.
Xenogenetic Interactions
Complementation and Rescue Data
Expression of Vap-33AScer\UAS.cPa under the control of Scer\GAL4C164 rescues nearly 100% of the indirect flight muscle mitochondrial defects seen in Vap-33Aunspecified adults.
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Stocks (1)
Notes on Origin
External Crossreferences and Linkouts ( 0 )
Synonyms and Secondary IDs (5)
Reported As
Symbol Synonym
Name Synonyms
Saccharomyces cerevisiae UAS construct a of Pennetta
Secondary FlyBase IDs
    References (8)