Pianissimo (PIA)

RICTOR and MTOR (FRAP1) are components of a protein complex that integrates nutrient- and growth factor-derived signals to regulate cell growth. The deduced 1,708-amino acid protein has a calculated molecular mass of 192 kD. RICTOR contains evolutionarily conserved sequences, notably an N-terminal region of about 200 amino acids and several smaller regions, including a repeated block of 20 amino acids.Rapamycin treatment of human embryonic kidney cells eliminated the binding of MTOR to RAPTOR, but did not affect the interaction of MTOR with RICTOR. Knockdown of RICTOR caused accumulation of thick actin fibers throughout much of the cytoplasm in HeLa cells, loss of actin at the cell cortex, altered distribution of cytoskeletal proteins, and reduced protein kinase C (PKC)-alpha activity.