This entry represents the C-lobe of FERM domain found in protein-tyrosine phosphatases non-receptor type-14 (PTPN14, also known as Pez) and type-21 (PTPN21). A number of mutations in Pez/PTPN14 have been shown to be associated with breast and colorectal cancer []. PTPN14 and PTPN21 contain an N-terminal FERM domain and a C-terminal PTP catalytic domain. The FERM domain has a cloverleaf tripart structure composed of: (1) FERM_N (A-lobe or F1); (2) FERM_M (B-lobe, or F2); and (3) FERM_C (C-lobe or F3). The C-lobe/F3 within the FERM domain is part of the PH domain family. Like most other ERM members they have a phosphoinositide-binding site in their FERM domain. The FERM C domain is the third structural domain within the FERM domain. The FERM domain is found in the cytoskeletal-associated proteins such as ezrin, moesin, radixin, 4.1R, and merlin. These proteins provide a link between the membrane and cytoskeleton and are involved in signal transduction pathways. The FERM domain is also found in protein tyrosine phosphatases (PTPs) , the tyrosine kinases FAK and JAK, in addition to other proteins involved in signaling. This domain is structurally similar to the PH and PTB domains and consequently is capable of binding to both peptides and phospholipids at different sites [, ].
