FB2026_01 , released March 12, 2026
FB2026_01 , released March 12, 2026
Allele: Dmel\ToporsZ4522
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General Information
Symbol
Dmel\ToporsZ4522
Species
D. melanogaster
Name
FlyBase ID
FBal0154837
Feature type
allele
Associated gene
Associated Insertion(s)
Carried in Construct
Key Links
Genomic Maps

Nature of the Allele
Progenitor genotype
Cytology
Description

Amino acid replacement: E345K.

Nucleotide substitution: G1160A.

Mutations Mapped to the Genome
Curation Data
Type
Location
Additional Notes
References
Nucleotide change:

G18974486A

Reported nucleotide change:

G1160A

Amino acid change:

E345K | Topors-PA; E345K | Topors-PB

Reported amino acid change:

E345K

Variant Molecular Consequences
Associated Sequence Data
DNA sequence
Protein sequence
 
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
Phenotype Manifest In
Detailed Description
Statement
Reference

Homozygous and transheterozygous males, but not females, show near random segregation of all chromosomes at meiosis I, but not meiosis II, as a result of non-disjunction. Male fecundity is also greatly reduced.

Nuclear blebbing is observed in late-stage ToporsZ4522 spermatocytes, though it is variable. Blebbing is not observed in testis sheath cells, larval neuroblasts or the giant nuclei of the larval salivary gland cells.

Homozygous males are fertile, but their progeny show paternal chromosome loss (loss rate of paternal chromosome 4 is 30%). The chromosome loss occurs during spermatogenesis and is premeiotic.

External Data
Interactions
Show genetic interaction network for Enhancers & Suppressors
Phenotypic Class
Phenotype Manifest In
Suppressor of
Statement
Reference

ToporsZ4522/nbl[+] is a suppressor of wing margin phenotype of ct6

ToporsZ4522/nbl[+] is a suppressor of wing margin phenotype of ctK

NOT Suppressor of
Statement
Reference

ToporsZ4522/nbl[+] is a non-suppressor of wing margin phenotype of ctn

ToporsZ4522/ToporsZ4522 is a non-suppressor of wing margin phenotype of ct6

Additional Comments
Genetic Interactions
Statement
Reference

Heterozygosity, but not homozygosity, for ToporsZ4522 restores the wing margin of ct6 flies.

Heterozygosity for ToporsZ4522 only slightly suppresses the wing margin phenotype of ctK flies.

Xenogenetic Interactions
Statement
Reference
Complementation and Rescue Data
Comments
Images (0)
Mutant
Wild-type
Stocks (1)
Notes on Origin
Discoverer
External Crossreferences and Linkouts ( 0 )
Synonyms and Secondary IDs (3)
Reported As
Symbol Synonym
ToporsZ4522
dtoporsZ4522
Name Synonyms
Secondary FlyBase IDs
    References (2)