TIAM1
Domain
The first PH domain mediates interaction with membranes enriched in phosphoinositides.
Function
Guanyl-nucleotide exchange factor that activates RHO-like proteins and connects extracellular signals to cytoskeletal activities. Activates RAC1, CDC42, and to a lesser extent RHOA and their downstream signaling to regulate processes like cell adhesion and cell migration.
Involvement in disease
Neurodevelopmental disorder with language delay and seizures
NEDLDS
An autosomal recessive disorder characterized by global developmental delay, intellectual disability, speech delay, and seizures. Additional features may include axial hypotonia, peripheral hypertonia, hypothyroidism, and non-specific dysmorphic features or brain imaging abnormalities.
None
The disease may be caused by variants affecting the gene represented in this entry.
Post-translational modifications
Ubiquitinated. Undergoes 'Lys-48' ubiquitination at Lys-1404 and Lys-1420 by a CUL3(KBTBD6/7) E3 ubiquitin ligase complex composed of CUL3, RBX1, KBTBD6 and KBTBD7. 'Lys-48' ubiquitination at Lys-1404 and Lys-1420 triggers proteasomal degradation (PubMed:25684205). Ubiquitination at Lys-1404 and Lys-1420 by CUL3(KBTBD6/7) also requires the membrane-associated protein GABARAP and may therefore be spatially restricted within the cell (PubMed:25684205).
Sequence Similarities
Belongs to the TIAM family.
Tissue Specificity
Found in virtually all analyzed tumor cell lines including B- and T-lymphomas, neuroblastomas, melanomas and carcinomas.
Cellular localization
- Cell junction
- Cell membrane
- Peripheral membrane protein
- Cytoplasmic side
- Detected at the boundary between cells with actin-rich protrusions (By similarity). Presence of KRIT1, CDH5 and RAP1B is required for its localization to the cell junction.
Alternative names
Rho guanine nucleotide exchange factor TIAM1, T-lymphoma invasion and metastasis-inducing protein 1, TIAM-1, TIAM1