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General Information
Symbol
Dmel\sqd1
Species
D. melanogaster
Name
FlyBase ID
FBal0035696
Feature type
allele
Associated gene
Associated Insertion(s)
Carried in Construct
Key Links
Nature of the Allele
Mutations Mapped to the Genome
 
Type
Location
Additional Notes
References
Associated Sequence Data
DNA sequence
Protein sequence
 
 
Progenitor genotype
Cytology
Nature of the lesion
Statement
Reference

Mutation affecting a germ-line promoter.

Insertion components
P{ry11}sqd1
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

Eggs laid by females homozygous for sqd1 display severe dorsal-ventral patterning defects, they are strongly dorsalised and are not fertilised. Embryos from sqd1 females expressing the sqdS transgene, show distinct anterior-posterior patterning defects characterised by head defects and deletion of anterior structures. Cuticle preparations from sqdS ; sqd1/Df(3R)urd females exhibit a range of anterior defects. These embryos do not have posterior patterning defects, as they all have the correct number of abdominal segments. Embryos from sqd1 females expressing the sqdA isoform do not show these anterior patterning defects, nor do they have posterior group phenotypes, indicating that the sqdA can at least partially rescue the dorsal-ventral patterning defects of sqd1 embryos.

sqd1 escaper females produce oocytes with an AP polarity defect at a 43% penetrance; sqdj4B4/sqd1 clones show the same phenotype at a 65% penetrance.

Of the eggs laid by sqd1/sqdK12 transheterozygotes, around 50 % exhibit some degree of dorsalisation: the least affected have widely spaced dorsal appendage and an enlarged operculum; intermediately affected have a single broad appendage that spans at least the width of the normal appendages; severely affected (<5%) have a crown of appendage material that surrounds the anterior circumference of the egg. In sqd1/sqd1 females, nurse cell chromosomes fail to disperse after stage 6, but instead arrest in the blob like conformation typical at stage 6 of oogenesis.

Homozygous females produce dorsalised eggs which have dorsal appendage material expanding to the ventral side of the eggshell and which lack the dorsal midline cells (which are normally found between the dorsal appendages).

Embryos are strongly dorsalised. Hemizygotes are female sterile.

External Data
Interactions
Show genetic interaction network for Enhancers & Suppressors
Phenotypic Class
Phenotype Manifest In
Enhanced by
Suppressed by
Statement
Reference

sqd1 has nurse cell & nuclear chromosome phenotype, suppressible | partially by otu104

Other
Statement
Reference

Hrb27C10280/Hrb27Ck16203, sqd1/sqdK12 has nurse cell & nuclear chromosome phenotype

Hrb27C10280/Hrb27Ck10413, sqd1/sqdK12 has nurse cell & nuclear chromosome phenotype

Additional Comments
Genetic Interactions
Statement
Reference

Dorsalisation of the eggs laid by sqd1/sqdK12 transheterozygotes is enhanced by Hrb27C10280/Hrb27Ck16203, so that >98% show some degree of dorsalisation, and by Hrb27C10280/Hrb27Ck10413 or Hrb27C02647/Hrb27C377, so that 100% show some degree of dorsalisation. In sqd1/sqdK12; Hrb27C10280/Hrb27Ck10413 and sqd1/sqdK12; Hrb27C10280/Hrb27Ck16203 females, nurse cell chromosomes fail to disperse after stage 6, but instead arrest in the blob like conformation typical at stage 6 of oogenesis. otu104 suppresses the penetrance of the chromosome morphology phenotype of sqd1 homozygous nurse cells from 98% to 17% (1 copy) or 8% (2 copies) of egg chambers.

Xenogenetic Interactions
Statement
Reference
Complementation and Rescue Data
Partially rescued by

sqd1 is partially rescued by sqdA

sqd1 is partially rescued by sqdA

sqd1 is partially rescued by sqdB

sqd1 is partially rescued by sqdS

sqd1 is partially rescued by sqdA

sqd1 is partially rescued by sqdS

Not rescued by

sqd1 is not rescued by sqdB

sqd1 is not rescued by sqdS

sqd1 is not rescued by sqdB

Comments

Expression of the sqdB isoform is not sufficient to rescue the sqd1 dorsal-ventral patterning defects, such that the eggs remain unfertilised.

The failure of chromosome dispersal after stage 6 in the nurse cells of sqd1 homozygous females is reduced from 97% penetrance to 86% by 2XsqdA, 46% by 2XsqdB and 39% by 2XsqdS. Rescue is more effective when 2 isoforms are combined: sqdA + sqdB reduces penetrance to 4%, as does sqdB + sqdS; sqdA + sqdS reduces penetrance to 8%.

Images (0)
Mutant
Wild-type
Stocks (0)
Notes on Origin
Discoverer
Comments
Comments

Full fertility and normal polarity was restored by P-element excision by Jumpstart.

External Crossreferences and Linkouts ( 0 )
Synonyms and Secondary IDs (3)
Reported As
Name Synonyms
Secondary FlyBase IDs
    References (12)