| Description | 982 amino acids; 120 kDa; the overall structure of CBLb is very close to the sructure of CBL: the evolutionarily conserved aminoterminal region of CBL is composed of three interacting domains: a four-helix bundle (4H), an EF-hand calcium binding domain, and a divergent SH2 domain; the three domains together form an integrated phosphoprotein -recognition module; this aminoterminal region is followed by a central Ring finger with a Cys3HisCys4 motif and an aminoterminal region with multiple proline-rich sequences, a putative leucine zipper and several potential tyrosine phosphorylation sites; two alternatively spliced mRNA code form CBLb proteins lacking the leucine zipper |
| Expression | expression of CBLb was seen in several human adult tissues including lung, spleen and testis but not in human brain, liver, pancreas, salivary gland or skeletal muscle; expression was also detected in fetal brain and liver, in hematopoietic cell lines and in normal and malignant mammary epithelial cell lines |
| Localisation | cytoplasmic |
| Function | regulation of signal transduction; CBLb has been shown to inhibit c-Jun terminal kinase (JNK) activation mediated by the (VAV oncoprotein and EGF receptor (EGFR) signaling; in contrast, a direct interaction between CBLb and the kinase ZAP-70 induces a positive signal in T cells |
| Cbl-b, a member of the Sli-1/c-Cbl protein family, inhibits Vav-mediated c-Jun N-terminal kinase activation. |
| Bustelo XR, Crespo P, López-Barahona M, Gutkind JS, Barbacid M |
| Oncogene. 1997 ; 15 (21) : 2511-2520. |
| PMID 9399639 |
| |
| cbl-b inhibits epidermal growth factor receptor signaling. |
| Ettenberg SA, Keane MM, Nau MM, Frankel M, Wang LM, Pierce JH, Lipkowitz S |
| Oncogene. 1999 ; 18 (10) : 1855-1866. |
| PMID 10086340 |
| |
| Cloning and characterization of cbl-b: a SH3 binding protein with homology to the c-cbl proto-oncogene. |
| Keane MM, Rivero-Lezcano OM, Mitchell JA, Robbins KC, Lipkowitz S |
| Oncogene. 1995 ; 10 (12) : 2367-2377. |
| PMID 7784085 |
| |
| The CBL-related protein CBLB participates in FLT3 and interleukin-7 receptor signal transduction in pro-B cells. |
| Lavagna-Sé C, Marchetto S, Birnbaum D, Rosnet O |
| The Journal of biological chemistry. 1998 ; 273 (24) : 14962-14967. |
| PMID 9614102 |
| |
| A direct interaction between the adaptor protein Cbl-b and the kinase zap-70 induces a positive signal in T cells. |
| Zhang Z, Elly C, Qiu L, Altman A, Liu YC |
| Current biology : CB. 1999 ; 9 (4) : 203-206. |
| PMID 10074432 |
| |
