Tob1 (IPR015677)

Short name: Tob1

Overlapping homologous superfamilies


Family relationships

  • Tob1/2 (IPR015676)
    • Tob1 (IPR015677)


Tob1 (transducer of ErbB2) is a member of the BTG/Tob family. Studies in mice carrying a targeted deletion of the Tob1 gene indicate that Tob1 is a negative regulator of osteogenesis and Tob1 has been shown to inhibit bone morphogenetic protein (BMP) signalling by interacting with receptor-regulated Smads in osteoblasts [PMID: 12782279]. In addition, Tob1 null mice are prone to spontaneous tumour formation [PMID: 12756225] and Tob1 expression is decreased in lung cancers [PMID: 14643028]. These findings suggest that Tob1 acts as a tumour suppressor protein, and it has been shown that the Tob protein can inhibit cell cycle progression from the G0/G1 to S phases. This cell cycle regulatory function may occur in part, through their interaction with CAF1 [PMID: 10602502].

The BTG/Tob family members contain an conserved N-terminal domain, known as APRO domain (AntiPROliferative) or BTG domain. In mammals, six family members have been identified: BTG1, BTG2/PC3/Tis21, BTG3/ANA, BTG4/PC3B, Tob1/Tob and Tob2. They interact with CAF1, a subunit of the CCR4-NOT complex. They display antiproliferative properties as their ectopic expression in a variety of cell lines reduced cell proliferation [PMID: 19746446].

GO terms

Biological Process

GO:0008285 negative regulation of cell proliferation

Molecular Function

No terms assigned in this category.

Cellular Component

No terms assigned in this category.

Contributing signatures

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