FB2026_03 , released September 17, 2026
Physical Interaction report
Open Close
General Information
Interaction Type
Interacting Genes
FlyBase ID
FBig0000100004
Interaction Network
Interactions Browser links
cup network
bru1 network
Reported Interactions
FBrf0167488-17.Y2H
Description
physical association
Assay
Collection
Source/Stage
Cell line used
Participants
Corresponds to
Reported as
Role
Note
cup 

Cup

bait

fused to LexA DNA-binding domain

bru1 

Bru

prey

fused to the B42 activation domain

Experimental entities
Corresponds to
Identifier
Reported
Role
Note
Subregions with role in interaction
Corresponds to
Description
Role
Coordinates
Note
Isoform-specific participants
Corresponds to
Description
Role
Note
Comments concerning this interaction

Source was yeast cell line; bait produced as transgenic fusion protein; prey produced as transgenic fusion protein (prey from ovary cDNA expression library).

Two-hybrid system: yeast LexA-BD/B42-AD.

FBrf0167488-18.Y2H
Description
physical association
Assay
Collection
Source/Stage
Cell line used
Participants
Corresponds to
Reported as
Role
Note
cup 

Cup

bait

fused to LexA DNA-binding domain

cup 
bru1 

Bru

prey

fused to the B42 activation domain

bru1 
Experimental entities
Corresponds to
Identifier
Reported
Role
Note
Subregions with role in interaction
Corresponds to
Description
Role
Coordinates
Note
cup 
region
sufficient binding region
aa 821-920aa 921-1132
bru1 
region
sufficient binding region
aa 320-520
Isoform-specific participants
Corresponds to
Description
Role
Note
Comments concerning this interaction

Source was yeast cell line; bait produced as transgenic fusion protein; prey produced as transgenic fusion protein (prey was previously cloned reagent).

Two-hybrid system: yeast LexA-BD/B42-AD.

FBrf0167488-21.coIP.WB
Description
physical association
Collection
Source/Stage
Cell line used
Participants
Corresponds to
Reported as
Role
Note
cup 

Cup

bait
bru1 

Bru

prey
Experimental entities
Corresponds to
Identifier
Reported
Role
Note
Subregions with role in interaction
Corresponds to
Description
Role
Coordinates
Note
Isoform-specific participants
Corresponds to
Description
Role
Note
Comments concerning this interaction

Source was adult ovary of wild-type fly line; bait produced from endogenous gene; prey produced from endogenous gene.

In the presence of RNase during immunoprecipitation this interaction was still observed, indicating that it is not mediated through RNA in the RNP complex; may be direct.

FBrf0227674-2.PD.WB
Reference
Description
physical association
Collection
Source/Stage
Cell line used
Participants
Corresponds to
Reported as
Role
Note
cup 

Cup

bait

GST tag

bru1 

Bru

prey

His6 tag

bru1 
bru1 
Experimental entities
Corresponds to
Identifier
Reported
Role
Note
Subregions with role in interaction
Corresponds to
Description
Role
Coordinates
Note
bru1 
interaction domain 1
mutation disrupting interaction
aa 1-146

Disrupts interaction only if aa 334-416 is also deleted.

bru1 
interaction domain 2
mutation disrupting interaction
aa 334-416

Disrupts interaction only if aa 1-146 is also deleted.

Isoform-specific participants
Corresponds to
Description
Role
Note
Comments concerning this interaction

Interaction in vitro; bait produced as a recombinant fusion protein in bacterial system; prey produced as a recombinant fusion protein in bacterial system.

Removal of both domains of aret (aa 1-146 and aa 334-416) is necessary to disrupt the interaction with cup.

FBrf0227674-4.PD.WB
Reference
Description
physical association
Collection
Source/Stage
Cell line used
Participants
Corresponds to
Reported as
Role
Note
cup 

Cup

bait

GST tag

bru1 

Bru

prey

His6 tag

bru1 
bru1 
bru1 
Experimental entities
Corresponds to
Identifier
Reported
Role
Note
Subregions with role in interaction
Corresponds to
Description
Role
Coordinates
Note
bru1 
interacting amino acid 7
mutation decreasing interaction
aa 7

S7E requires the mutation T135E to decrease the interaction.

bru1 
interacting amino acid 135
mutation decreasing interaction
aa 135

T135E requires the mutation S7E to decrease the interaction.

bru1 
interacting amino acid 4
mutation decreasing interaction
aa 4

S4E requires the mutation S7E to decrease the interaction.

Isoform-specific participants
Corresponds to
Description
Role
Note
Comments concerning this interaction

Interaction in vitro; bait produced as a recombinant fusion protein in bacterial system; prey produced as a recombinant fusion protein in bacterial system.

aret S7E requires the mutation aret T135E to decrease the interaction while aret T135E also requires the mutation aret S7E to decrease the interaction. Additionally, aret S4E requires the mutation aret S7E to decrease the interaction. Together, aret S7E, T135E, and S4E greatly reduce the interaction.

FBrf0262483-31.CL.FM
Description
physical association
Collection
Source/Stage
Cell line used
Participants
Corresponds to
Reported as
Role
Note
cup 

cup

bait

mCherry tag, fused to the plasma membrane

bru1 

Bruno

prey

EGFP tag

Experimental entities
Corresponds to
Identifier
Reported
Role
Note
Subregions with role in interaction
Corresponds to
Description
Role
Coordinates
Note
Isoform-specific participants
Corresponds to
Description
Role
Note
Comments concerning this interaction

cup was fused to a plasma membrane anchor. The ability of this chimera to recruit prey protein to the plasma membrane was taken as evidence of direct physical interaction.

Source was live S2R+ cells; bait and prey produced from endogenous genes.

External Crossreferences and Linkouts ( 1 )
Linkouts
MIST - An integrated Molecular Interaction Database
References (3)