Domain

Adaptor protein Cbl, PTB domain (IPR024159)

Short name: Cbl_PTB

Domain relationships

None.

Description

Cbl (Casitas B-lineage lymphoma) is an adaptor protein that functions as a negative regulator of many signalling pathways that start from receptors at the cell surface.

The N-terminal region of Cbl contains a Cbl-type phosphotyrosine-binding (Cbl-PTB) domain, which is composed of three evolutionarily conserved domains: an N-terminal four-helix bundle (4H) domain, an EF hand-like calcium-binding domain, and a divergent SH2-like domain. The calcium-bound EF-hand wedges between the 4H and SH2 domains, and roughly determines their relative orientation. The Cbl-PTB domain has also been named Cbl N-terminal (Cbl-N) or tyrosine kinase binding (TKB) domain [PMID: 10078535, PMID: 18840649].

The N-terminal 4H domain contains four long alpha-helices. The C and D helices in this domain pack against the adjacent EF-hand-like domain, and a highly conserved loop connecting the A and B helices contacts the SH2-like domain. The EF-hand motif is similar to classical EF-hand proteins. The SH2-like domain retains the general helix-sheet-helix architecture of the SH2 fold, but lacks the secondary beta-sheet, comprising beta-strands D', E and F, and also a prominent BG loop [PMID: 10078535].

This entry represents the Cbl-PTB domain.

GO terms

Biological Process

No terms assigned in this category.

Molecular Function

GO:0001784 phosphotyrosine binding

Cellular Component

No terms assigned in this category.

Contributing signatures

Signatures from InterPro member databases are used to construct an entry.
PROSITE profiles