This entry represents the protein disabled (DAB) and related proteins. It includes DAB from Drosophila melanogaster and its mammlian homologues, DAB1 and DAB2 (also known as DOC1 and DOC2). This group of proteins are adapter proteins that play roles in development. In Drosophila melanogaster, DAB acts as an adapter protein for SH2-domain containing proteins in the sevenless (sev) signalling pathway []. Together with Abl, it is involved in embryonic neural development []. In mammals, DAB1 is implicated in neuronal development []. In humans, DAB2 is an adapter protein that functions as clathrin-associated sorting protein (CLASP) required for clathrin-mediated endocytosis of selected cargo proteins []. It is involved in several signalling pathways and plays an important part in cell growth and development [, , ].
This entry represents the probable inorganic carbon transporter subunit DabA, which is part of an energy-coupled inorganic carbon pump together with DabB subunit in DAB operons (DAB1 and DAB2), found in a wide range of bacteria and archaea. DAB operon is required for CO2 concentrating mechanisms []. The substrate of this subunit may be CO2 rather than carbonate ions based on kinetic calculations and in experimental assays in which E.coli was deleted of its carbonic anhydrase genes and expression of DAB2 operon restores its growth. Structural homology modelling suggests that DabA contains a domain that is distantly homologous to a type II beta-carbonic anhydrase (CA).
