Pleckstrin Homology Domain Containing Family A, Member 3 (PLEKHA3)

By searching EST databases for proteins containing a putative phosphatidylinositol 3,4,5-trisphosphate-binding motif (PPBM), Dowler et al. (2000) identified PLEKHA3, which they designated FAPP1. The deduced 300-amino acid protein contains an N-terminal pleckstrin homology (PH) domain and a C-terminal proline-rich putative SH3-binding motif. Dowler et al. (2000) concluded that FAPP1 is likely to be expressed widely, because they identified 27 FAPP1 ESTs derived from several tissues. Their inability to detect FAPP1 mRNA expression, however, suggested that it is a low-abundance transcript.Dowler et al. (2000) determined that the isolated PH domain of FAPP1 interacted with high affinity with phosphatidylinositol 4-phosphate (PtdIns(4)P), but not with any other phosphoinositides tested.