The DBB domain is named from the Drosophila (Downstream of FGFR - Dof, also known as Heartbroken or Stumps) protein, the BANKS and BCAP, both signalling in B-cell pathway, proteins. This domain defines a minimal region required for mediating Dof dimerisation. Since this domain can interact both with itself and with a region in the C-terminal part of the molecule, it may mediate either intermolecular or intramolecular interactions PMID:12767830. Mutants lacking this domain disrupt FGFR signal transduction and fibroblast growth-factor signalling PMID:14993266.
The following proteins share a number of distinct parts, namely with ankyrin repeats a coiled coil, and a stretch of approximately 140 amino acid residues the development of the immune system in higher upstream of the ankyrin repeats, which has been called the Dof/BCAP/BANK (DBB) domain [ (PUBMED:12767830) (PUBMED:14993266) ]:
Drosophila Downstream-of-EGF receptor (Dof), a protein essential for the morphogenesis of both the mesoderm and the tracheae. It has been proposed to mediate the transmission of a signal from an activated receptor to other components of the cell, including the MAP kinase cascade.
Vertebrate BANK and BCAP proteins that function in B-cell signalling.
These proteins are involved in signalling; however, unlike Dof, BANK and BCAP are not implicated in FGF signalling but appear to have undergone rapid change during the course of evolution to acquire a novel function with vertebrates.
The DBB domain in both Dof and BCAP is required to mediate self-association in yeast cells, indicating that this domain may have a more general role in mediating protein-protein interactions [ (PUBMED:12767830) ].
Family alignment:
There are 773 DBB domains in 773 proteins in SMART's nrdb database.
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Evolution (species in which this domain is found)
Taxonomic distribution of proteins containing DBB domain.
This tree includes only several representative species. The complete taxonomic breakdown of all proteins with DBB domain is also avaliable.
Click on the protein counts, or double click on taxonomic names to display all proteins containing DBB domain in the selected taxonomic class.
A functional domain of Dof that is required for fibroblast growth factorsignaling.
Mol Cell Biol. 2004; 24: 2263-76
Display abstract
Signal transduction by fibroblast growth factor (FGF) receptors in Drosophiladepends upon the intracellular protein Dof, which has been proposed to actdownstream of the receptors and upstream of Ras. Dof is the product of afast-evolving gene whose vertebrate homologs, BCAP and BANK, are involved insignaling downstream of the B-cell receptor. Mapping functional domains withinDof revealed that neither of its potential interaction motifs, the ankyrinrepeats and the coiled coil, is essential for the function of Dof. However, wehave identified a region within the N terminus of the protein with similarity to BCAP and BANK, which we refer to as the Dof, BCAP, and BANK (DBB) motif, that it is required for FGF-dependent signal transduction and is necessary for efficient interaction of Dof with the FGF receptor Heartless. In addition, we demonstratethat Dof is phosphorylated in the presence of an activated FGF receptor and that tyrosine residues could contribute to the function of the molecule.
Isolation of proteins that interact with the signal transduction molecule Dof andidentification of a functional domain conserved between Dof and vertebrate BCAP.
J Mol Biol. 2003; 329: 479-93
Display abstract
Dof is a large molecule essential for signal transduction by the two FGFreceptors in Drosophila. It contains two ankyrin repeats and a coiled-coilregion, but has no other recognisable structural motif. Dof shares these featureswith its closest vertebrate relatives, the B-cell signalling molecules BCAP andBANK. In addition, this family of proteins shares a region of homology upstreamof the ankyrin repeats, which we call the Dof/BCAP/BANK (DBB) motif. We haveidentified 44 proteins that interact with Dof in a yeast two-hybrid screen. Theseinclude the Drosophila FGF-receptor Heartless and Dof itself. We show that theintegrity of the DBB motif is required both for Dof and for BCAP to form dimers. Analysis of the interactions between a set of deletion constructs of Dof and the panel of interactors suggests that Dof may adopt different conformations, with a folded conformation stabilized by interactions between the DBB motif and theC-terminal part of the protein.
Links (links to other resources describing this domain)
