FB2026_03 , released September 17, 2026
Physical Interaction report
Open Close
General Information
Interaction Type
physical association
Interacting Genes
IKKε, spn-F
FlyBase ID
FBig0000101614
Interaction Network
Interactions Browser links
IKKε network
spn-F network
Reported Interactions
FBrf0205990-1.coIP.WB
Reference
Dubin-Bar et al., 2008
Description
physical association
Assay
Collection
Source/Stage
Cell line used
S2-DGRC
Participants
Corresponds to
Reported as
Role
Note
IKKε 

Ik2

bait

GFP tag

spn-F 

Spn-F

prey

HA tag

spn-F 
Experimental entities
Corresponds to
Identifier
Reported
Role
Note
Subregions with role in interaction
Corresponds to
Description
Role
Coordinates
Note
spn-F 
C-terminal region
sufficient binding region
aa 187-364

\'C-Spn-F\'

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

Source was cell extract of S2 cell line; bait produced from transfected construct; prey produced from transfected construct.

(Dubin-Bar et al., 2008)
FBrf0205990-2.coIP.WB
Reference
Dubin-Bar et al., 2008
Description
physical association
Assay
Collection
Source/Stage
ovary / adult stagefemale
Cell line used
Participants
Corresponds to
Reported as
Role
Note
IKKε 

Ik2

bait

GFP tag

spn-F 

Spn-F

prey

HA 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

Source was adult female ovary of transgenic fly line; bait produced from tagged transgenic construct; prey produced from tagged transgenic construct.

(Dubin-Bar et al., 2008)
FBrf0205990-3.SPR
Reference
Dubin-Bar et al., 2008
Description
physical association
Assay
Collection
Source/Stage
Cell line used
Participants
Corresponds to
Reported as
Role
Note
IKKε 

Ik2

bait

MBP tag, His tag

spn-F 

Spn-F

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

spn-F binds ik2 with submicromolar affinity, Kd = 407.2 nM.

(Dubin-Bar et al., 2008)

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

(Dubin-Bar et al., 2008)
FBrf0205990-4.ENZ.A
Reference
Description
Assay
Collection
Source/Stage
Cell line used
Participants
Corresponds to
Reported as
Role
Note
IKKε 

Ik2

enzyme

GFP tag

IKKε 

Ik2

enzyme

GFP tag

IKKε 
spn-F 

Spn-F

enzyme target

His tag, [32]P label

spn-F 

Spn-F

enzyme target

His tag, [32]P label

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
FBrf0205990-5.coIP.WB
Reference
Dubin-Bar et al., 2008
Description
physical association
Assay
Collection
Source/Stage
Cell line used
S2-DGRC
Participants
Corresponds to
Reported as
Role
Note
IKKε 

Ik2

bait

Myc tag

spn-F 

Spn-F

prey

HA 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

Source was cell extract of S2 cell line; bait produced from transfected construct; prey produced from transfected construct.

(Dubin-Bar et al., 2008)

A kinase-dead version of ik2 (K41A) still coimmunoprecipitates spn-F; ik2 phosphorylation of spn-F is not essential for their physical interaction.

(Dubin-Bar et al., 2008)
FBrf0223108-1.coIP.WB
Reference
Amsalem et al., 2013
Description
physical association
Assay
Collection
Source/Stage
Cell line used
S2-DGRC
Participants
Corresponds to
Reported as
Role
Note
spn-F 

Spn-F

bait

GFP tag

spn-F 
spn-F 
IKKε 

Ik2

prey
Experimental entities
Corresponds to
Identifier
Reported
Role
Note
Subregions with role in interaction
Corresponds to
Description
Role
Coordinates
Note
spn-F 
N-terminal and central region
sufficient binding region
aa 1-280

\'Spn-FΔC\'

spn-F 
second coiled-coil domain
sufficient binding region
aa 210-243

\'Spn-FΔC\'

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

Source was cell extract of S2 cell line; bait produced from transfected construct; prey produced from transfected construct.

(Amsalem et al., 2013)
FBrf0228877-1.coIP.WB
Reference
Otani et al., 2015
Description
physical association
Assay
Collection
Source/Stage
ovary / femaleadult stage
Cell line used
Participants
Corresponds to
Reported as
Role
Note
spn-F 

Spn-F

bait
IKKε 

IKKε

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 female ovaries of wild-type fly line; bait produced from endogenous gene; prey produced from endogenous gene.

(Otani et al., 2015)
FBrf0228877-2.coIP.WB
Reference
Otani et al., 2015
Description
physical association
Assay
Collection
Source/Stage
Cell line used
S2-unspecified
Participants
Corresponds to
Reported as
Role
Note
spn-F 

Spn-F

bait

GFP tag

spn-F 
spn-F 
IKKε 

IKKε

prey

HA tag

Experimental entities
Corresponds to
Identifier
Reported
Role
Note
Subregions with role in interaction
Corresponds to
Description
Role
Coordinates
Note
spn-F 
coiled-coil region 2
sufficient binding region
aa 191-273

"C1" construct, coordinates relative to spn-F-PA

spn-F 
IKKε-interacting region
necessary binding region
aa 211-253

"Δ212" and "Δ231" constructs, coordinates relative to spn-F-PA

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

Source was cell extract of S2 cell line; bait produced from transfected construct; prey produced from transfected construct.

(Otani et al., 2015)
FBrf0230080-4.coIP.WB
Reference
Lin et al., 2015
Description
physical association
Assay
Collection
Source/Stage
Cell line used
S2-DGRC
Participants
Corresponds to
Reported as
Role
Note
IKKε 

Ik2

bait

FLAG

spn-F 

SpnF

prey

myc

spn-F 
Experimental entities
Corresponds to
Identifier
Reported
Role
Note
Subregions with role in interaction
Corresponds to
Description
Role
Coordinates
Note
spn-F 
CC3 domain
mutation disrupting interaction
aa 210-241
Isoform-specific participants
Corresponds to
Description
Role
Note
Comments concerning this interaction

Source was cell extract of S2 cell line; bait produced from transfected construct; prey produced from transfected construct.

(Lin et al., 2015)

Removal of the CC3 domain from spn-F disrupts the interaction.

(Lin et al., 2015)
FBrf0246588-1.coIP.MS
Reference
Lu et al., 2020
Description
physical association
Assay
Collection
Source/Stage
organism / adult stage
Cell line used
Participants
Corresponds to
Reported as
Role
Note
spn-F 

Spn-F

bait

GFP tag

IKKε 

IKKε

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 adults of transgenic fly line; bait produced from tagged transgenic construct; prey produced from endogenous gene.

(Lu et al., 2020)
External Crossreferences and Linkouts ( 1 )
Linkouts
MIST - An integrated Molecular Interaction Database
References (5)